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Sample records for homozygous inactivating mutations

  1. Homozygous Inactivating Mutation in NANOS3 in Two Sisters with Primary Ovarian Insufficiency

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    Mariza G. Santos

    2014-01-01

    Full Text Available Despite the increasing understanding of female reproduction, the molecular diagnosis of primary ovarian insufficiency (POI is seldom obtained. The RNA-binding protein NANOS3 poses as an interesting candidate gene for POI since members of the Nanos family have an evolutionarily conserved function in germ cell development and maintenance by repressing apoptosis. We performed mutational analysis of NANOS3 in a cohort of 85 Brazilian women with familial or isolated POI, presenting with primary or secondary amenorrhea, and in ethnically-matched control women. A homozygous p.Glu120Lys mutation in NANOS3 was identified in two sisters with primary amenorrhea. The substituted amino acid is located within the second C2HC motif in the conserved zinc finger domain of NANOS3 and in silico molecular modelling suggests destabilization of protein-RNA interaction. In vitro analyses of apoptosis through flow cytometry and confocal microscopy show that NANOS3 capacity to prevent apoptosis was impaired by this mutation. The identification of an inactivating missense mutation in NANOS3 suggests a mechanism for POI involving increased primordial germ cells (PGCs apoptosis during embryonic cell migration and highlights the importance of NANOS proteins in human ovarian biology.

  2. A homozygous inactivating calcium-sensing receptor mutation, Pro339Thr, is associated with isolated primary hyperparathyroidism: correlation between location of mutations and severity of hypercalcaemia

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    Hannan, Fadil Mohammed; Nesbit, M. Andrew; Christie, Paul; Lissens, Willy; Vanderschueren, Bart; Bex, Marie; Bouillon, Roger; Thakker, Rajesh V.

    2010-01-01

    Abstract Background: Inactivating mutations of the calcium-sensing receptor (CaSR), a G-protein coupled receptor with extracellular (ECD), transmembrane (TMD) and intracellular (ICD) domains, cause familial hypocalciuric hypercalcaemia, neonatal severe primary hyperparathyroidism, and occasionally primary hyperparathyroidism in adults. Objective: To investigate a patient with typical symptomatic primary hyperparathyroidism for CaSR abnormalities. Patient and Design: A 51-year...

  3. Homozygous Desmocollin-2 Mutations and Arrhythmogenic Cardiomyopathy.

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    Lorenzon, Alessandra; Pilichou, Kalliopi; Rigato, Ilaria; Vazza, Giovanni; De Bortoli, Marzia; Calore, Martina; Occhi, Gianluca; Carturan, Elisa; Lazzarini, Elisabetta; Cason, Marco; Mazzotti, Elisa; Poloni, Giulia; Mostacciuolo, Maria Luisa; Daliento, Luciano; Thiene, Gaetano; Corrado, Domenico; Basso, Cristina; Bauce, Barbara; Rampazzo, Alessandra

    2015-10-15

    Dominant mutations in desmocollin-2 (DSC2) gene cause arrhythmogenic cardiomyopathy (ACM), a progressive heart muscle disease characterized by ventricular tachyarrhythmias, heart failure, and risk of juvenile sudden death. Recessive mutations are rare and are associated with a cardiac or cardiocutaneous phenotype. Here, we evaluated the impact of a homozygous founder DSC2 mutation on clinical expression of ACM. An exon-by-exon analysis of the DSC2 coding region was performed in 94 ACM index patients. The c.536A>G (p.D179G) mutation was identified in 5 patients (5.3%), 4 of which resulted to be homozygous carriers. The 5 subjects shared a conserved haplotype, strongly indicating a common founder. Genetic and clinical investigation of probands' families revealed that p.D179G homozygous carriers displayed severe forms of biventricular cardiomyopathy without hair or skin abnormalities. The only heterozygous proband, who carried an additional variant of unknown significance in αT-catenin gene, showed a mild form of ACM without left ventricular involvement. All heterozygous family members were clinically asymptomatic. In conclusion, this is the first homozygous founder mutation in DSC2 gene identified among Italian ACM probands. Our findings provide further evidence of the occurrence of recessive DSC2 mutations in patients with ACM predominantly presenting with biventricular forms of the disease. Copyright © 2015 Elsevier Inc. All rights reserved.

  4. Homozygous mutation in the NPHP3 gene causing foetal nephronophthisis

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    Abdullah, Uzma; Farooq, Muhammad; Fatima, Ambrin

    2017-01-01

    We present a case of a foetal sonographic finding of hyper-echogenic kidneys, which led to a strategic series of genetic tests and identified a homozygous mutation (c.424C > T, p. R142*) in the NPHP3 gene. Our study provides a rare presentation of NPHP3-related ciliopathy and adds to the mutation...

  5. Homozygous STIL mutation causes holoprosencephaly and microcephaly in two siblings.

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    Charlotte Mouden

    Full Text Available Holoprosencephaly (HPE is a frequent congenital malformation of the brain characterized by impaired forebrain cleavage and midline facial anomalies. Heterozygous mutations in 14 genes have been identified in HPE patients that account for only 30% of HPE cases, suggesting the existence of other HPE genes. Data from homozygosity mapping and whole-exome sequencing in a consanguineous Turkish family were combined to identify a homozygous missense mutation (c.2150G>A; p.Gly717Glu in STIL, common to the two affected children. STIL has a role in centriole formation and has previously been described in rare cases of microcephaly. Rescue experiments in U2OS cells showed that the STIL p.Gly717Glu mutation was not able to fully restore the centriole duplication failure following depletion of endogenous STIL protein indicating the deleterious role of the mutation. In situ hybridization experiments using chick embryos demonstrated that expression of Stil was in accordance with a function during early patterning of the forebrain. It is only the second time that a STIL homozygous mutation causing a recessive form of HPE was reported. This result also supports the genetic heterogeneity of HPE and increases the panel of genes to be tested for HPE diagnosis.

  6. Clinical evaluation of two consanguineous families with homozygous mutations in BEST1

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    Piñeiro-Gallego, Teresa; Álvarez, María; Pereiro, Inés

    2011-01-01

    To describe the clinical and genetic findings in two consanguineous families with Best vitelliform macular dystrophy (BVMD) and homozygous mutations in the bestrophin-1 (BEST1) gene.......To describe the clinical and genetic findings in two consanguineous families with Best vitelliform macular dystrophy (BVMD) and homozygous mutations in the bestrophin-1 (BEST1) gene....

  7. Progressive hereditary spastic paraplegia caused by a homozygous KY mutation.

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    Yogev, Yuval; Perez, Yonatan; Noyman, Iris; Madegem, Anwar Abu; Flusser, Hagit; Shorer, Zamir; Cohen, Eugene; Kachko, Leonid; Michaelovsky, Analia; Birk, Ruth; Koifman, Arie; Drabkin, Max; Wormser, Ohad; Halperin, Daniel; Kadir, Rotem; Birk, Ohad S

    2017-08-01

    Twelve individuals of consanguineous Bedouin kindred presented with autosomal recessive progressive spastic paraplegia evident as of age 0-24 months, with spasticity of lower limbs, hyperreflexia, toe walking and equinus deformity. Kyphoscolisois was evident in older patients. Most had atrophy of the lateral aspects of the tongue and few had intellectual disability. Nerve conduction velocity, electromyography and head and spinal cord magnetic resonance imaging were normal in tested subjects. Muscle biopsy showed occasional central nuclei and fiber size variability with small angular fibers. Genome-wide linkage analysis identified a 6.7Mbp disease-associated locus on chromosome 3q21.3-3q22.2 (LOD score 9.02; D3S1290). Whole-exome sequencing identified a single homozygous variant within this locus, c.51_52ins(28); p.(V18fs56*) in KY, segregating in the family as expected and not found in 190 Bedouin controls. High KY transcript levels were demonstrated in muscular organs with lower expression in the CNS. The phenotype is reminiscent of kyphoscoliosis seen in Ky null mice. Two recent studies done independently and parallel to ours describe somewhat similar phenotypes in one and two patients with KY mutations. KY encodes a tranglutaminase-like peptidase, which interacts with muscle cytoskeletal proteins and is part of a Z-band protein complex, suggesting the disease mechanism may resemble myofibrillar myopathy. However, the mixed myopathic-neurologic features caused by human and mouse Ky mutations are difficult to explain by loss of KY sarcomere stabilizing function alone. KY transcription in CNS tissues may imply that it also has a role in neuromotor function, in line with the irregularity of neuromuscular junction in Ky null mutant mice.

  8. Novel homozygous nonsense mutations in the luteinizing hormone receptor (LHCGR) gene associated with 46,XY primary amenorrhea.

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    Ben Hadj Hmida, Imen; Mougou-Zerelli, Soumaya; Hadded, Anis; Dimassi, Sarra; Kammoun, Molka; Bignon-Topalovic, Joelle; Bibi, Mohamed; Saad, Ali; Bashamboo, Anu; McElreavey, Ken

    2016-07-01

    To determine the genetic cause of 46,XY primary amenorrhea in three 46,XY girls. Whole exome sequencing. University cytogenetics center. Three patients with unexplained 46,XY primary amenorrhea were included in the study. Potentially pathogenic variants were confirmed by Sanger sequencing, and familial segregation was determined where parents' DNA was available. Exome sequencing was performed in the three patients, and the data were analyzed for potentially pathogenic mutations. The functional consequences of mutations were predicted. Three novel homozygous nonsense mutations in the luteinizing hormone receptor (LHCGR) gene were identified:c.1573 C→T, p.Gln525Ter, c.1435 C→T p.Arg479Ter, and c.508 C→T, p.Gln170Ter. Inactivating mutations of the LHCGR gene may be a more common cause of 46,XY primary amenorrhea than previously considered. Copyright © 2016 American Society for Reproductive Medicine. Published by Elsevier Inc. All rights reserved.

  9. Early onset obesity and adrenal insufficiency associated with a homozygous POMC mutation

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    Eng Christine M

    2011-07-01

    Full Text Available Abstract Isolated hypocortisolism due to ACTH deficiency is a rare condition that can be caused by homozygous or compound heterozygous mutations in the gene encoding proopiomelanocortin (POMC. Loss of function mutations of POMC gene typically results in adrenal insufficiency, obesity and red hair. We describe an 18 month old Hispanic female with congenital adrenal insufficiency, a novel POMC mutation and atypical clinical features. The patient presented at the age of 9 months with hypoglycemia and the endocrine evaluation resulted in a diagnosis of ACTH deficiency. She developed extreme weight gain prompting sequence analysis of POMC, which revealed a homozygous c.231C > A change which is predicted to result in a premature termination codon. The case we report had obesity, hypocortisolism but lacked red hair which is typical for subjects with POMC mutations. Mutations of POMC should be considered in individuals with severe early onset obesity and adrenal insufficiency even when they lack the typical pigmentary phenotype.

  10. Homozygous inactivation of CHEK2 is linked to a familial case of multiple primary lung cancer with accompanying cancers in other organs.

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    Kukita, Yoji; Okami, Jiro; Yoneda-Kato, Noriko; Nakamae, Ikuko; Kawabata, Takeshi; Higashiyama, Masahiko; Kato, Junya; Kodama, Ken; Kato, Kikuya

    2016-11-01

    In clinical practice, there are a number of cancer patients with clear family histories, but the patients lack mutations in known familial cancer syndrome genes. Recent advances in genomic technologies have enhanced the possibility of identifying causative genes in such cases. Two siblings, an elder sister and a younger brother, were found to have multiple primary lung cancers at the age of 60. The former subsequently developed breast cancer and had a history of uterine myoma. The latter had initially developed prostate cancer at the age of 59 and had a history of colon cancer. Single-nucleotide polymorphism (SNP) genotyping revealed that ∼10% of the genomes were homozygous in both patients. Exome sequencing revealed nonsynonymous mutations in five genes in the runs of homozygosity: CHEK2, FCGRT, INPP5J, MYO18B, and SFI1. Evolutionary conservation of primary protein structures suggested the functional importance of the CHEK2 mutation, p.R474C. This mutation altered the tertiary structure of CHK2 by disrupting the salt bridge between p.R474 and p.E394. No such structural changes were observed with the other mutated genes. Subsequent cell-based transfection analysis revealed that CHK2 p.R474C was unstable and scarcely activated. We concluded that the homozygous CHEK2 variant was contributory in this case of familial cancer. Although homozygous inactivation of CHEK2 in mice led to cancers in multiple organs, accumulation of additional human cases is needed to establish its pathogenic role in humans.

  11. Homozygous mutation of the PHOX2B gene in congenital central hypoventilation syndrome (Ondine's Curse).

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    Trochet, Delphine; de Pontual, Loïc; Estêvao, Maria Helena; Mathieu, Yves; Munnich, Arnold; Feingold, J; Goridis, Christo; Lyonnet, Stanislas; Amiel, Jeanne

    2008-05-01

    Homozygosity for a dominant allele is relatively rare and preferentially observed in communities with high inbreeding. According to the definition of true dominance, similar phenotypes should be observed in patients heterozygous and homozygous for a dominant mutation. However, the homozygous phenotype usually tends to be more severe than the heterozygous one. In these cases, the wild-type and mutant alleles are semi-dominant. Here we report a patient with a Congenital Central Hypoventilation Syndrome (CCHS) phenotype and homozygosity for a PHOX2B gene mutation leading to an alanine expansion shorter than the threshold hitherto observed in CCHS patients with a heterozygous mutation. This observation adds the concept of mutational threshold per se to the discussion about dominant and recessive alleles.

  12. Novel homozygous missense mutation in NT5C2 underlying hereditary spastic paraplegia SPG45.

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    Straussberg, Rachel; Onoufriadis, Alexandros; Konen, Osnat; Zouabi, Yasmin; Cohen, Lior; Lee, John Y W; Hsu, Chao-Kai; Simpson, Michael A; McGrath, John A

    2017-11-01

    SPG45 is a rare form of autosomal recessive spastic paraplegia associated with mental retardation. Detailed phenotyping and mutation analysis was undertaken in three individuals with SPG45 from a consanguineous family of Arab Muslim origin. Using whole-exome sequencing, we identified a novel homozygous missense mutation in NT5C2 (c.1379T>C; p.Leu460Pro). Our data expand the molecular basis of SPG45, adding the first missense mutation to the current database of nonsense, frameshift, and splice site mutations. NT5C2 mutations seem to have a broad clinical spectrum and should be sought in patients manifesting either as uncomplicated or complicated HSP. © 2017 Wiley Periodicals, Inc.

  13. Mutational Profile of Homozygous β-Thalassemia in Rio de Janeiro, Brazil.

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    Carrocini, Gisele C S; Venancio, Larissa P R; Pessoa, Viviani L R; Lobo, Clarisse L C; Bonini-Domingos, Claudia R

    2017-01-01

    β-Thalassemia (β-thal) is a hemolytic anemia that is caused by point mutations in most cases. The Brazilian population is highly heterogeneous and knowledge of the mutations that make up the genotypic profile of individuals can contribute information about the formation of the population and clinical condition of patients. In this study, we evaluated the mutations present in homozygous β-thal patients from Rio de Janeiro, Brazil. We analyzed 24 samples of peripheral blood of patients with homozygous β-thal. To identify the mutations, we carried out allele-specific-polymerase chain reaction (AS-PCR) and DNA sequencing. We found 11 different mutations on the β-globin gene. Among the most frequent mutations observed were HBB: c.92 + 6T>C, followed by HBB: c.93-21G>A, HBB: c.118C>T and HBB: c.92 + 1G>A. We also identified the rare mutation HBB: c.75T>A that was reported in an individual carrying Hb S (HBB: c.20A>T)/β-thal (HBB: c.75T>A) but not in Brazilian thalassemic patients, thus, this is the first report of this mutation in Brazilian β-thal patients. For its multiethnic character, Brazil has different mutations that cause β-thal and that are distributed with different frequencies according to the regions of the country. Our findings contribute to the description of the mutational profile of Brazilian thalassemic patients, showing wide heterogeneity and genetic variability.

  14. Autoimmune lymphoproliferative syndrome caused by a homozygous null FAS ligand (FASLG) mutation

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    Magerus-Chatinet, Aude; Stolzenberg, Marie-Claude; Lanzarotti, Nina; Neven, Bénédicte; Daussy, Cécile; Picard, Capucine; Neveux, Nathalie; Desai, Mukesh; Rao, Meghana; Ghosh, Kanjaksha; Madkaikar, Manisha; Fischer, Alain; Rieux-Laucat, Frédéric

    2013-01-01

    Background Autoimmune lymphoproliferative syndrome (ALPS) is characterized by chronic nonmalignant lymphoproliferation, accumulation of double-negative T cells, hypergammaglobulinemia G and A, and autoimmune cytopenia. Objectives Although mostly associated with FAS mutations, different genetic defects leading to impaired apoptosis have been described in patients with ALPS, including the FAS ligand gene (FASLG) in rare cases. Here we report on the first case of complete FAS ligand deficiency caused by a homozygous null mutant. Methods Double-negative T-cell counts and plasma IL-10 and FAS ligand concentrations were determined as ALPS markers. The FASLG gene was sequenced, and its expression was analyzed by means of Western blotting. FAS ligand function was assessed based on reactivation-induced cell death. Results We describe a patient born to consanguineous parents who presented with a severe form of ALPS caused by FASLG deficiency. Although the clinical presentation was compatible with a homozygous FAS mutation, FAS-induced apoptosis was normal, and plasma FAS ligand levels were not detectable. This patient carries a homozygous, germline, single-base-pair deletion in FASLG exon 1, leading to a premature stop codon (F87fs x95) and a complete defect in FASLG expression. The healthy parents were each heterozygous for the mutation, confirming its recessive trait. Conclusion FAS ligand deficiency should be screened in patients presenting with ALPS features but lacking the usual markers, including plasma soluble FAS ligand and an in vitro apoptotic defect. An activation-induced cell death test could help in discrimination. PMID:22857792

  15. The construction and application of diploid sake yeast with a homozygous mutation in the FAS2 gene.

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    Kotaka, Atsushi; Sahara, Hiroshi; Hata, Yoji

    2010-12-01

    In Japanese sake brewing, cerulenin-resistant sake yeasts produce elevated levels of ethyl caproate, an important flavor component. The FAS2 mutation FAS2-1250S of Saccharomyces cerevisiae generates a cerulenin-resistant phenotype. This mutation is dominant, and, in general, cerulenin-resistant diploid sake yeast strains carry this mutation heterozygously. Here we constructed diploid sake yeast with a homozygous mutation of FAS2 using the high-efficiency loss of heterozygosity method. The homozygous mutants grew more slowly in YPD medium than did the wild-type and heterozygous mutants, and they produced more ethyl caproate during sake brewing. In addition, although both the wild-type and heterozygous mutant were sensitive to 4 mg/l cerulenin, the homozygous mutant was resistant to more than 4 mg/l cerulenin. Next, we obtained a homozygous mutant of FAS2 without inducing genetic modification. After cultivating the heterozygous FAS2 mutant K-1801 in YPD, homozygous mutants were selected on medium containing high concentrations of cerulenin. Non-genetically modified yeast with a homozygous mutation of FAS2 produced 2.2-fold more ethyl caproate than did heterozygous yeast. Moreover, high-quality Japanese sake with a very rich flavor could be brewed using yeast containing a homozygous mutation in the FAS2 gene. Copyright © 2010. Published by Elsevier B.V.

  16. Homozygous Carrier of Prothrombin G20210A Mutation with Massive Pulmonary Embolism and His Family: Gender Differences of Susceptibility to Mutation

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    Stoeva Natalia Y.

    2016-03-01

    Full Text Available Prothrombin 20210 G>A mutation is the second most frequent inherited factor increasing the risk for developing venous thromboembolism (VTE. The risk for VTE in homozygous carriers of this mutation is not well studied because of their rarity are rare. We report a case of a homozygous carrier of prothrombin mutation: a young man with massive pulmonary embolism, and his family - an asymptomatic homozygous sister, heterozygous parents with asymptomatic mother, and father with history of deep venous thrombosis (DVT. To our knowledge, this is the first reported case of homozygous prothrombin mutation carriers in Bulgaria and the other Balkan countries. We conclude that the homozygous prothrombin mutation creates predisposition for VTE that can manifest or not depending on additional factors, one of which could be male gender.

  17. A homozygous mutation in keratin 5 is a fully dominant allele responsible for epidermolysis bullosa simplex

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    Stephens, K.; Smith, L.; Ehrlich, P. [Univ. of Washington, Seattle, WI (United States)] [and others

    1994-09-01

    Molecular, ultrastructural, and clinical analysis of a large family with epidermolysis bullosa simplex (EBS) and multiple consanguineous marriages has identified one affected individual who inherited defective keratin 5 genes from both of her affected parents. EBS are skin blistering disorders caused by abnormal keratin filament assembly or function due to a mutation in either of the two structural proteins keratin 5 or keratin 14. Linkage analysis with DNA markers near each keratin gene demonstrated that the defect in this family mapped near keratin 5 (K5) with a LOD score of 7.60, {theta}=0.0 for the proximal marker D12S14. Sequencing of the K5 gene identified an Asn substitution of a highly conserved Lys at codon 173 in the 5{prime} end of the central rod domain. The mutation was found in 33 affected family members but not in 5 unaffected members or 25 unrelated, unaffected individuals. Both linkage and sequence analysis verified that one affected individual was homozygous for the K5 mutation. In this family, clinical examination and analysis of epidermal ultrastructure by electron microscopy were consistent with the Koebner subtype of EBS. Despite the absence of any normal K5 protein in the skin, the clinical and ultrastructural phenotypes of the homozygous individual did not differ significantly from those of affected heteozygous relatives. This K5 mutation is a fully dominant allele.

  18. A homozygous nonsense mutation (c.214C->A) in the biliverdin reductase alpha gene (BLVRA) results in accumulation of biliverdin during episodes of cholestasis.

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    Nytofte, Nikolaj S; Serrano, Maria A; Monte, Maria J; Gonzalez-Sanchez, Ester; Tumer, Zeynep; Ladefoged, Karin; Briz, Oscar; Marin, Jose J G

    2011-04-01

    Green jaundice is a rare finding usually associated with end-stage liver disease. OBJECTIVE The authors investigated two unrelated Inuit women from different geographical areas in Greenland who had episodes of green jaundice associated with biliary obstruction. The crises were accompanied by increased biochemical markers of cholestasis, together with absent or moderate hyperbilirubinaemia. In contrast, high-performance liquid chromatography tandem mass spectrometry showed hypercholanaemia and high concentrations of biliverdin IXα in serum, urine, bile and milk. Hyperbiliverdinaemia disappeared after surgical correction of the cholestasis. Analysis of the coding sequence of the biliverdin reductase alpha (BVRα) gene (BLVRA) detected three single-nucleotide polymorphisms: c.90G→A, c.214C→A and c.743A→C, which result in p.Ala3Thr, p.Ser44X and p.Gly220Gly, respectively. With the use of TaqMan probes, homozygosity for c.214C→A was found in both patients. Both parents of one of these patients were heterozygous for the inactivating mutation. Her brother was homozygous for normal alleles. Although her sister was also homozygous for the c.214C→A mutation, she had never had hyperbiliverdinaemia or cholestasis. With the use of human liver RNA, the BVRα coding sequence was cloned, and the variant containing c.214C→A was generated by site-directed mutagenesis. Both proteins were expressed in human hepatoma liver cells and Xenopus laevis oocytes. Immunoblotting, immunofluorescence and functional assays of BVRα activity revealed that the mutated sequence generates a truncated protein with no catalytic activity. This is the first report of a homozygous BLVRA inactivating mutation indicating that the complete absence of BVRα activity is a non-lethal condition, the most evident phenotypic characteristic of which is the appearance of green jaundice accompanying cholestasis episodes.

  19. Epidermolysis Bullosa with Pyloric Atresia and Aplasia Cutis in a Newborn Due to Homozygous Mutation in ITGB4.

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    Kayki, Gozdem; Bozkaya, Davut; Ozaltin, Fatih; Orhan, Diclehan; Kaymaz, Figen; Korkmaz, Emine; Yigit, Sule

    2017-08-01

    Epidermolysis bullosa with pyloric atresia (EB-PA) is an autosomal recessive disorder due to mutations in ITGA6 and/or ITGB4, resulting in altered expression of α6β4 integrin. EB-PA can also occur with aplasia cutis. We present a newborn with EB-PA and aplasia cutis, born of consanguineous parents, with a homozygous c.3793+1G>A mutation affecting ITGB4, previously described only in the heterozygous state with other mutations. The previously unreported homozygous c.3793+1G>A mutation affecting ITGB4 causes a severe form of junctional epidermolysis bullosa with pyloric atresia and aplasia cutis.

  20. Homozygous LIPE mutation in siblings with multiple symmetric lipomatosis, partial lipodystrophy, and myopathy.

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    Zolotov, Sagit; Xing, Chao; Mahamid, Riad; Shalata, Adel; Sheikh-Ahmad, Mohammed; Garg, Abhimanyu

    2017-01-01

    Despite considerable progress in identifying causal genes for lipodystrophy syndromes, the molecular basis of some peculiar adipose tissue disorders remains obscure. In an Israeli-Arab pedigree with a novel autosomal recessive, multiple symmetric lipomatosis (MSL), partial lipodystrophy and myopathy, we conducted exome sequencing of two affected siblings to identify the disease-causing mutation. The 41-year-old female proband and her 36-year-old brother reported marked accumulation of subcutaneous fat in the face, neck, axillae, and trunk but loss of subcutaneous fat from the lower extremities and progressive distal symmetric myopathy during adulthood. They had increased serum creatine kinase levels, hypertriglyceridemia and low levels of high-density lipoprotein cholesterol. Exome sequencing identified a novel homozygous NC_000019.9:g.42906092C>A variant on chromosome 19, leading to a NM_005357.3:c.3103G>T nucleotide change in coding DNA and corresponding p.(Glu1035*) protein change in hormone sensitive lipase (LIPE) gene as the disease-causing variant. Sanger sequencing further confirmed the segregation of the mutation in the family. Hormone sensitive lipase is the predominant regulator of lipolysis from adipocytes, releasing free fatty acids from stored triglycerides. The homozygous null LIPE mutation could result in marked inhibition of lipolysis from some adipose tissue depots and thus may induce an extremely rare phenotype of MSL and partial lipodystrophy in adulthood associated with complications of insulin resistance, such as diabetes, hypertriglyceridemia and hepatic steatosis. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

  1. Pure Cerebellar Ataxia with Homozygous Mutations in the PNPLA6 Gene.

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    Wiethoff, Sarah; Bettencourt, Conceição; Paudel, Reema; Madon, Prochi; Liu, Yo-Tsen; Hersheson, Joshua; Wadia, Noshir; Desai, Joy; Houlden, Henry

    2017-02-01

    Autosomal-recessive cerebellar ataxias (ARCA) are clinically and genetically heterogeneous conditions primarily affecting the cerebellum. Mutations in the PNPLA6 gene have been identified as the cause of hereditary spastic paraplegia and complex forms of ataxia associated with retinal and endocrine manifestations in a field where the genotype-phenotype correlations are rapidly expanding. We identified two cousins from a consanguineous family belonging to a large Zoroastrian (Parsi) family residing in Mumbai, India, who presented with pure cerebellar ataxia without chorioretinal dystrophy or hypogonadotropic hypogonadism. We used a combined approach of clinical characterisation, homozygosity mapping, whole-exome and Sanger sequencing to identify the genetic defect in this family. The phenotype in the family was pure cerebellar ataxia. Homozygosity mapping revealed one large region of shared homozygosity at chromosome 19p13 between affected individuals. Within this region, whole-exome sequencing of the index case identified two novel homozygous missense variants in the PNPLA6 gene at c.3847G>A (p.V1283M) and c.3929A>T (p.D1310V) in exon 32. Both segregated perfectly with the disease in this large family, with only the two affected cousins being homozygous. We identified for the first time PNPLA6 mutations associated with pure cerebellar ataxia in a large autosomal-recessive Parsi kindred. Previous mutations in this gene have been associated with a more complex phenotype but the results here suggest an extension of the associated disease spectrum.

  2. Autoimmune lymphoproliferative syndrome caused by a homozygous null FAS ligand (FASLG) mutation.

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    Magerus-Chatinet, Aude; Stolzenberg, Marie-Claude; Lanzarotti, Nina; Neven, Bénédicte; Daussy, Cécile; Picard, Capucine; Neveux, Nathalie; Desai, Mukesh; Rao, Meghana; Ghosh, Kanjaksha; Madkaikar, Manisha; Fischer, Alain; Rieux-Laucat, Frédéric

    2013-02-01

    Autoimmune lymphoproliferative syndrome (ALPS) is characterized by chronic nonmalignant lymphoproliferation, accumulation of double-negative T cells, hypergammaglobulinemia G and A, and autoimmune cytopenia. Although mostly associated with FAS mutations, different genetic defects leading to impaired apoptosis have been described in patients with ALPS, including the FAS ligand gene (FASLG) in rare cases. Here we report on the first case of complete FAS ligand deficiency caused by a homozygous null mutant. Double-negative T-cell counts and plasma IL-10 and FAS ligand concentrations were determined as ALPS markers. The FASLG gene was sequenced, and its expression was analyzed by means of Western blotting. FAS ligand function was assessed based on reactivation-induced cell death. We describe a patient born to consanguineous parents who presented with a severe form of ALPS caused by FASLG deficiency. Although the clinical presentation was compatible with a homozygous FAS mutation, FAS-induced apoptosis was normal, and plasma FAS ligand levels were not detectable. This patient carries a homozygous, germline, single-base-pair deletion in FASLG exon 1, leading to a premature stop codon (F87fs x95) and a complete defect in FASLG expression. The healthy parents were each heterozygous for the mutation, confirming its recessive trait. FAS ligand deficiency should be screened in patients presenting with ALPS features but lacking the usual markers, including plasma soluble FAS ligand and an in vitro apoptotic defect. An activation-induced cell death test could help in discrimination. Copyright © 2012 American Academy of Allergy, Asthma & Immunology. Published by Mosby, Inc. All rights reserved.

  3. A novel null homozygous mutation confirms CACNA2D2 as a gene mutated in epileptic encephalopathy.

    Directory of Open Access Journals (Sweden)

    Tommaso Pippucci

    Full Text Available Contribution to epileptic encephalopathy (EE of mutations in CACNA2D2, encoding α2δ-2 subunit of Voltage Dependent Calcium Channels, is unclear. To date only one CACNA2D2 mutation altering channel functionality has been identified in a single family. In the same family, a rare CELSR3 polymorphism also segregated with disease. Involvement of CACNA2D2 in EE is therefore not confirmed, while that of CELSR3 is questionable. In a patient with epilepsy, dyskinesia, cerebellar atrophy, psychomotor delay and dysmorphic features, offspring to consanguineous parents, we performed whole exome sequencing (WES for homozygosity mapping and mutation detection. WES identified extended autozygosity on chromosome 3, containing two novel homozygous candidate mutations: c.1295delA (p.Asn432fs in CACNA2D2 and c.G6407A (p.Gly2136Asp in CELSR3. Gene prioritization pointed to CACNA2D2 as the most prominent candidate gene. The WES finding in CACNA2D2 resulted to be statistically significant (p = 0.032, unlike that in CELSR3. CACNA2D2 homozygous c.1295delA essentially abolished α2δ-2 expression. In summary, we identified a novel null CACNA2D2 mutation associated to a clinical phenotype strikingly similar to the Cacna2d2 null mouse model. Molecular and statistical analyses together argued in favor of a causal contribution of CACNA2D2 mutations to EE, while suggested that finding in CELSR3, although potentially damaging, is likely incidental.

  4. Jervell and Lange-Nielsen syndrome with homozygous missense mutation of the KCNQ1 gene.

    Science.gov (United States)

    Kılıç, Esra; Ertuğrul, İlker; Özer, Sema; Alikaşifoğlu, Mehmet; Aktaş, Dilek; Boduroğlu, Koray; Ütine, Gülen Eda

    2014-01-01

    Jervell and Lange-Nielsen syndrome (JLNS) is an autosomal recessive cardioauditory ion channel disorder characterized by congenital bilateral sensorineural deafness and long QT interval. JLNS is a ventricular repolarization abnormality and is caused by mutations in the KCNQ1 or KCNE1 gene. It has a high mortality rate in childhood due to ventricular tachyarrhythmias, episodes of torsade de pointes which may cause syncope or sudden cardiac death. Here, we present a 4.5-year-old female patient who had a history of syncope and congenital sensorineural deafness. She had a cochlear implant operation at 15 months of age and received an implantable cardioverter defibrillator (ICD) at 3 years of age because of recurrent syncope attacks. Five months after cochlear implant placement, she could say her first words and is now able to speak. With β-blocker therapy and ICD, she has remained syncope-free for a year. On the current admission, the family visited the genetics department to learn about the possibility of prenatal diagnosis of sensorineural deafness, as the mother was 9 weeks pregnant. A diagnosis of JLNS was established for the first time, and a homozygous missense mutation in the KCNQ1 gene (c.128 G>A, p.R243H) was detected. Heterozygous mutations of KCNQ1 were identified in both parents, thereby allowing future prenatal diagnoses. The family obtained prenatal diagnosis for the current pregnancy, and fetal KCNQ1 analysis revealed the same homozygous mutation. The pregnancy was terminated at the 12th week of gestation. The case presented here is the third molecularly confirmed Turkish JLNS case; it emphasizes the importance of timely genetic diagnosis, which allows appropriate genetic counseling and prenatal diagnosis, as well as proper management of the condition.

  5. Novel homozygous VHL mutation in exon 2 is associated with congenital polycythemia but not with cancer.

    Science.gov (United States)

    Lanikova, Lucie; Lorenzo, Felipe; Yang, Chunzhang; Vankayalapati, Hari; Drachtman, Richard; Divoky, Vladimir; Prchal, Josef T

    2013-05-09

    Germline von Hippel-Lindau (VHL) gene mutations underlie dominantly inherited familial VHL tumor syndrome comprising a predisposition for renal cell carcinoma, pheochromocytoma/paraganglioma, cerebral hemangioblastoma, and endolymphatic sac tumors. However, recessively inherited congenital polycythemia, exemplified by Chuvash polycythemia, has been associated with 2 separate 3' VHL gene mutations in exon 3. It was proposed that different positions of loss-of-function VHL mutations are associated with VHL syndrome cancer predisposition and only C-terminal domain-encoding VHL mutations would cause polycythemia. However, now we describe a new homozygous VHL exon 2 mutation of the VHL gene:(c.413C>T):P138L, which is associated in the affected homozygote with congenital polycythemia but not in her, or her-heterozygous relatives, with cancer or other VHL syndrome tumors. We show that VHL(P138L) has perturbed interaction with hypoxia-inducible transcription factor (HIF)1α. Further, VHL(P138L) protein has decreased stability in vitro. Similarly to what was reported in Chuvash polycythemia and some other instances of HIFs upregulation, VHL(P138L) erythroid progenitors are hypersensitive to erythropoietin. Interestingly, the level of RUNX1/AML1 and NF-E2 transcripts that are specifically upregulated in acquired polycythemia vera were also upregulated in VHL(P138L) granulocytes.

  6. A homozygous mutation of VWA3B causes cerebellar ataxia with intellectual disability.

    Science.gov (United States)

    Kawarai, Toshitaka; Tajima, Atsushi; Kuroda, Yukiko; Saji, Naoki; Orlacchio, Antonio; Terasawa, Hideo; Shimizu, Hirotaka; Kita, Yasushi; Izumi, Yuishin; Mitsui, Takao; Imoto, Issei; Kaji, Ryuji

    2016-06-01

    Hereditary cerebellar ataxia constitutes a heterogeneous group of neurodegenerative disorders, occasionally accompanied by other neurological features. Genetic defects remain to be elucidated in approximately 40% of hereditary cerebellar ataxia cases in Japan. We attempted to identify the gene responsible for autosomal recessive cerebellar ataxia with intellectual disability. The present study involved three patients in a consanguineous Japanese family. Neurological examination and gene analyses were performed in all family members. We performed genome-wide linkage analysis including single nucleotide polymorphism arrays, copy-number variation analysis and whole exome sequencing. To clarify the functional alteration resulting from the identified mutation, we performed cell viability assay of cultured cells expressing mutant protein. One homozygous region shared among the three patients on chromosomes 2p16.1-2q12.3 was identified. Using whole exome sequencing, six homozygous variants in genes in the region were detected. Only one variant, VWA3B c.A1865C, results in a change of a highly conserved amino acid (p.K622T) and was not present in control samples. VWA3B encodes a von Willebrand Factor A Domain-Containing Protein 3B with ubiquitous expression, including the cerebellum. The viability of cultured cells expressing the specific K622T mutation was proved to decrease through the activation of apoptotic pathway. Mutated VWA3B was found to be likely associated with cerebellar degeneration with intellectual disability. Although a rare cause of cerebellar degeneration, these findings indicate a critical role for VWA3B in the apoptosis pathway in neuronal tissues. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/

  7. Novel Homozygous LRP5 Mutations in Mexican Patients with Osteoporosis-Pseudoglioma Syndrome.

    Science.gov (United States)

    Astiazarán, Mirena C; Cervantes-Sodi, María; Rebolledo-Enríquez, Erick; Chacón-Camacho, Oscar; Villegas, Vanessa; Zenteno, Juan Carlos

    2017-12-01

    Osteoporosis-pseudoglioma syndrome (OPPG) is an uncommon autosomal recessive disorder characterized by the rare association of early-onset osteoporosis and severe ocular abnormalities such as persistent fetal vasculature and microphthalmia. Biallelic mutations in the low-density lipoprotein receptor-related protein-5 gene (LRP5) have been associated with OPPG. We present clinical and genetic data from three Mexican OPPG patients, a pair of sibs, and a sporadic case. Three patients underwent clinical examination, including a complete ophthalmic evaluation. Based on the clinical diagnosis of OPPG, the entire coding sequence of LRP5 was polymerase chain reaction-amplified and directly Sanger-sequenced. Genetic testing was extended to the parents of the affected patients. Phenotypic variability was observed in the familial case and molecular analysis identified a novel homozygous c.1145C>T, p.(Pro382Leu) variant in both sibs. As expected, their parents were heterozygous carriers. The sporadic patient exhibited a severe osseous phenotype, microphthalmia, and neurological symptoms. In this patient, homozygosity for the c.442C>T, p.(Gln148*) variant was demonstrated, whereas her parents were heterozygous carriers. The p.(Pro382Leu) pathogenic mutation has been previously reported only in a compound heterozygous state in OPPG patients. Two novel homozygous missense and nonsense variants were demonstrated in three OPPG cases from Mexico. Our results expand the spectrum of disease-causing LRP5 mutations. This is the first report of OPPG in our population and our findings may potentially add to a genotype-phenotype correlation.

  8. A novel homozygous YARS2 mutation causes severe myopathy, lactic acidosis, and sideroblastic anemia 2.

    Science.gov (United States)

    Nakajima, Junya; Eminoglu, Tuba F; Vatansever, Goksel; Nakashima, Mitsuko; Tsurusaki, Yoshinori; Saitsu, Hirotomo; Kawashima, Hisashi; Matsumoto, Naomichi; Miyake, Noriko

    2014-04-01

    Mitochondrial diseases are associated with defects of adenosine triphosphate production and energy supply to organs as a result of dysfunctions of the mitochondrial respiratory chain. Biallelic mutations in the YARS2 gene encoding mitochondrial tyrosyl-tRNA synthetase cause myopathy, lactic acidosis, and sideroblastic anemia 2 (MLASA2), a type of mitochondrial disease. Here, we report a consanguineous Turkish family with two siblings showing severe metabolic decompensation including recurrent hypoglycemia, lactic acidosis, and transfusion-dependent anemia. Using whole-exome sequencing of the proband and his parents, we identified a novel YARS2 mutation (c.1303A>G, p.Ser435Gly) that was homozygous in the patient and heterozygous in his parents. This mutation is located at the ribosomal protein S4-like domain of the gene, while other reported YARS2 mutations are all within the catalytic domain. Interestingly, the proband showed more severe symptoms and an earlier onset than previously reported patients, suggesting the functional importance of the S4-like domain in tyrosyl-tRNA synthetase.

  9. A novel homozygous mutation at the GAA gene in Mexicans with early-onset Pompe disease.

    Science.gov (United States)

    Esmer, Carmen; Becerra-Becerra, Rosario; Peña-Zepeda, Claudia; Bravo-Oro, Antonio

    2013-10-01

    Glycogen-storage disease type II, also named Pompe disease, is caused by the deficiency of the enzyme acid alpha-glucosidase, which originates lysosomal glycogen accumulation leading to progressive neuromuscular damage. Early-onset Pompe disease shows a debilitating and frequently fulminating course. To date, more than 300 mutations have been described; the majority of them are unique to each affected individual. Most early-onset phenotypes are associated with frameshift mutations leading to a truncated alpha-glucosidase protein with loss of function. Founder effects are responsible from many cases from few highprevalence world regions. Herein we described two apparently unrelated cases affected with classical early-onset Pompe disease, both pertaining to a small region from Central Mexico (the State of San Luis Potosí), the same novel homozygous frameshift mutation at gene GAA (c.1987delC) was demonstrated in both cases. This GAA gene deletion implies a change of glutamine to serine at codon 663, and a new reading frame that ends after 33 base pairs, which leads to the translation of a truncated protein. This report contributes to widen the knowledge on the effect of pathogenic mutations in Pompe disease. Here we postulate the existence of a founder effect.

  10. A syndrome of microcephaly, short stature, polysyndactyly, and dental anomalies caused by a homozygous KATNB1 mutation.

    Science.gov (United States)

    Yigit, Gökhan; Wieczorek, Dagmar; Bögershausen, Nina; Beleggia, Filippo; Möller-Hartmann, Claudia; Altmüller, Janine; Thiele, Holger; Nürnberg, Peter; Wollnik, Bernd

    2016-03-01

    Using whole-exome sequencing, we identified a homozygous acceptor splice-site mutation in intron 6 of the KATNB1 gene in a patient from a consanguineous Turkish family who presented with congenital microcephaly, lissencephaly, short stature, polysyndactyly, and dental abnormalities. cDNA analysis revealed complete loss of the natural acceptor splice-site resulting either in the usage of an alternative, exonic acceptor splice-site inducing a frame-shift and premature protein truncation or, to a minor extent, in complete skipping of exon 7. Both effects most likely lead to complete loss of KATNB1 function. Homozygous and compound heterozygous mutations in KATNB1 have very recently been described as a cause of microcephaly with brain malformations and seizures. We extend the KATNB1 associated phenotype by describing a syndrome characterized by primordial dwarfism, lissencephaly, polysyndactyly, and dental anomalies, which is caused by a homozygous truncating KATNB1 mutation. © 2015 Wiley Periodicals, Inc.

  11. Type B mandibuloacral dysplasia with congenital myopathy due to homozygous ZMPSTE24 missense mutation.

    Science.gov (United States)

    Ben Yaou, Rabah; Navarro, Claire; Quijano-Roy, Susana; Bertrand, Anne T; Massart, Catherine; De Sandre-Giovannoli, Annachiara; Cadiñanos, Juan; Mamchaoui, Kamel; Butler-Browne, Gillian; Estournet, Brigitte; Richard, Pascale; Barois, Annie; Lévy, Nicolas; Bonne, Gisèle

    2011-06-01

    Mutation in ZMPSTE24 gene, encoding a major metalloprotease, leads to defective prelamin A processing and causes type B mandibuloacral dysplasia, as well as the lethal neonatal restrictive dermopathy syndrome. Phenotype severity is correlated with the residual enzyme activity of ZMPSTE24 and accumulation of prelamin A. We had previously demonstrated that a complete loss of function in ZMPSTE24 was lethal in the neonatal period, whereas compound heterozygous mutations including one PTC and one missense mutation were associated with type B mandibuloacral dysplasia. In this study, we report a 30-year longitudinal clinical survey of a patient harboring a novel severe and complex phenotype, combining an early-onset progeroid syndrome and a congenital myopathy with fiber-type disproportion. A unique homozygous missense ZMPSTE24 mutation (c.281T>C, p.Leu94Pro) was identified and predicted to produce two possible ZMPSTE24 conformations, leading to a partial loss of function. Western blot analysis revealed a major reduction of ZMPSTE24, together with the presence of unprocessed prelamin A and decreased levels of lamin A, in the patient's primary skin fibroblasts. These cells exhibited significant reductions in lifespan associated with major abnormalities of the nuclear shape and structure. This is the first report of MAD presenting with confirmed myopathic abnormalities associated with ZMPSTE24 defects, extending the clinical spectrum of ZMPSTE24 gene mutations. Moreover, our results suggest that defective prelamin A processing affects muscle regeneration and development, thus providing new insights into the disease mechanism of prelamin A-defective associated syndromes in general.

  12. A Novel Homozygous Mutation in FOXC1 Causes Axenfeld Rieger Syndrome with Congenital Glaucoma.

    Directory of Open Access Journals (Sweden)

    Shazia Micheal

    Full Text Available Anterior segment dysgenesis (ASD disorders are a group of clinically and genetically heterogeneous phenotypes in which frequently cornea, iris, and lens are affected. This study aimed to identify novel mutations in PAX6, PITX2 and FOXC1 in families with anterior segment dysgenesis disorders.We studied 14 Pakistani and one Mexican family with Axenfeld Rieger syndrome (ARS; n = 10 or aniridia (n = 5. All affected and unaffected family members underwent full ophthalmologic and general examinations. Total genomic DNA was isolated from peripheral blood. PCR and Sanger sequencing were performed for the exons and intron-exon boundaries of the FOXC1, PAX6, and PITX2 genes.Mutations were identified in five of the 15 probands; four variants were novel and one variant was described previously. A novel de novo variant (c.225C>A; p.Tyr75* was identified in the PAX6 gene in two unrelated probands with aniridia. In addition, a known variant (c.649C>T; p.Arg217* in PAX6 segregated in a family with aniridia. In the FOXC1 gene, a novel heterozygous variant (c.454T>C; p.Trp152Arg segregated with the disease in a Mexican family with ARS. A novel homozygous variant (c.92_100del; p.Ala31_Ala33del in the FOXC1 gene segregated in a Pakistani family with ARS and congenital glaucoma.Our study expands the mutation spectrum of the PAX6 and FOXC1 genes in individuals with anterior segment dysgenesis disorders. In addition, our study suggests that FOXC1 mutations, besides typical autosomal dominant ARS, can also cause ARS with congenital glaucoma through an autosomal recessive inheritance pattern. Our results thus expand the disease spectrum of FOXC1, and may lead to a better understanding of the role of FOXC1 in development.

  13. Compound heterozygous or homozygous truncating MYBPC3 mutations cause lethal cardiomyopathy with features of noncompaction and septal defects

    Science.gov (United States)

    Wessels, Marja W; Herkert, Johanna C; Frohn-Mulder, Ingrid M; Dalinghaus, Michiel; van den Wijngaard, Arthur; de Krijger, Ronald R; Michels, Michelle; de Coo, Irenaeus FM; Hoedemaekers, Yvonne M; Dooijes, Dennis

    2015-01-01

    Familial hypertrophic cardiomyopathy (HCM) is usually caused by autosomal dominant pathogenic mutations in genes encoding sarcomeric or sarcomere-associated cardiac muscle proteins. The disease mainly affects adults, although young children with severe HCM have also been reported. We describe four unrelated neonates with lethal cardiomyopathy, and performed molecular studies to identify the genetic defect. We also present a literature overview of reported patients with compound heterozygous or homozygous pathogenic MYBPC3 mutations and describe their clinical characteristics. All four children presented with feeding difficulties, failure to thrive, and dyspnea. They died from cardiac failure before age 13 weeks. Features of left ventricular noncompaction were diagnosed in three patients. In the fourth, hypertrabeculation was not a clear feature, but could not be excluded. All of them had septal defects. Two patients were compound heterozygotes for the pathogenic c.2373dup p.(Trp792fs) and c.2827C>T p.(Arg943*) mutations, and two were homozygous for the c.2373dup and c.2827C>T mutations. All patients with biallelic truncating pathogenic mutations in MYBPC3 reported so far (n=21) were diagnosed with severe cardiomyopathy and/or died within the first few months of life. In 62% (13/21), septal defects or a patent ductus arteriosus accompanied cardiomyopathy. In contrast to heterozygous pathogenic mutations, homozygous or compound heterozygous truncating pathogenic MYBPC3 mutations cause severe neonatal cardiomyopathy with features of left ventricular noncompaction and septal defects in approximately 60% of patients. PMID:25335496

  14. Inactivation and inducible oncogenic mutation of p53 in gene targeted pigs.

    Directory of Open Access Journals (Sweden)

    Simon Leuchs

    Full Text Available Mutation of the tumor suppressor p53 plays a major role in human carcinogenesis. Here we describe gene-targeted porcine mesenchymal stem cells (MSCs and live pigs carrying a latent TP53(R167H mutant allele, orthologous to oncogenic human mutant TP53(R175H and mouse Trp53(R172H, that can be activated by Cre recombination. MSCs carrying the latent TP53(R167H mutant allele were analyzed in vitro. Homozygous cells were p53 deficient, and on continued culture exhibited more rapid proliferation, anchorage independent growth, and resistance to the apoptosis-inducing chemotherapeutic drug doxorubicin, all characteristic of cellular transformation. Cre mediated recombination activated the latent TP53(R167H allele as predicted, and in homozygous cells expressed mutant p53-R167H protein at a level ten-fold greater than wild-type MSCs, consistent with the elevated levels found in human cancer cells. Gene targeted MSCs were used for nuclear transfer and fifteen viable piglets were produced carrying the latent TP53(R167H mutant allele in heterozygous form. These animals will allow study of p53 deficiency and expression of mutant p53-R167H to model human germline, or spontaneous somatic p53 mutation. This work represents the first inactivation and mutation of the gatekeeper tumor suppressor gene TP53 in a non-rodent mammal.

  15. Lethal/severe osteogenesis imperfecta in a large family: a novel homozygous LEPRE1 mutation and bone histological findings

    NARCIS (Netherlands)

    van Dijk, Fleur S.; Nikkels, Peter G. J.; den Hollander, Nicolette S.; Nesbitt, Isabel M.; van Rijn, Rick R.; Cobben, Jan M.; Pals, Gerard

    2011-01-01

    We report a large consanguineous Turkish family in which multiple individuals are affected with autosomal recessive lethal or severe osteogenesis imperfecta (OI) due to a novel homozygous LEPRE1 mutation. In one affected individual histological studies of bone tissue were performed, which may

  16. A homozygous mutation in a consanguineous family consolidates the role of ALDH1A3 in autosomal recessive microphthalmia

    DEFF Research Database (Denmark)

    Roos, L; Fang, M; Dali, C

    2013-01-01

    to the identification of new genes. Very recently, homozygous variations within ALDH1A3 have been associated with autosomal recessive microphthalmia with or without cysts or coloboma, and with variable subphenotypes of developmental delay/autism spectrum disorder in eight families. In a consanguineous family where...... three of the five siblings were affected with microphthalmia/coloboma, we identified a novel homozygous missense mutation in ALDH1A3 using exome sequencing. Of the three affected siblings, one had intellectual disability and one had intellectual disability and autism, while the last one presented...

  17. Neonatal respiratory insufficiency caused by an (homozygous) ABCA3-stop mutation: a systematic evaluation of therapeutic options.

    Science.gov (United States)

    Winter, J; Essmann, S; Kidszun, A; Aslanidis, C; Griese, M; Poplawska, K; Bartsch, M; Schmitz, G; Mildenberger, E

    2014-04-01

    Autosomal recessive ABCA3 (ATP-binding cassette protein A3) gene mutations have been associated with neonatal respiratory distress and pediatric interstitial lung disease. The clinical course of the disease depends on the underlying mutations. Therefore, knowledge of course, symptoms and treatment of the disease is important. A term newborn suffered from progressive respiratory insufficiency, which led to death at the age of 4.8 months. The girl developed interstitial lung disease. Infections as well as structural and functional disorders of the lung were systematically excluded. A homozygous c.4681C > T (Arg 1561 Stop) mutation of the ABCA3 gene was identified. A literature review of the pathophysiology and treatment options of the disease was done. Therapeutic approaches with corticosteroids, macrolide, and hydroxychloroquine did not improve the clinical course. Therapeutic strategies for chronic interstitial lung disease have been used successfully in cases of a mild clinical course in juvenile patients with ABCA3 gene mutation. In our patient with homozygous ABCA3 gene mutation,they were not effective. Lung transplantation remains as a therapeutic option, but because of donor organ shortage and associated morbidity and mortality it is rarely feasible. More experience in the treatment of newborns with ABCA3 gene mutations is needed. Randomized, prospective evaluation of the different therapeutic approaches in a specific registry may improve prognosis and treatment of affected individuals. © Georg Thieme Verlag KG Stuttgart · New York.

  18. Identification of 2 novel homozygous mutations in the methylmalonyl-CoA mutase gene in Saudi patients

    Directory of Open Access Journals (Sweden)

    Sarar Mohamed

    2015-09-01

    Full Text Available The aim of this report is to analyze the clinical features, and mutations of the methylmalonyl CoA mutase (MUT gene in 2 patients with methylmalonic aciduria (MMA attending King Saud University Medical City, Riyadh, Saudi Arabia in January 2014. The infants aged 6 days (patient 1 and 3 months (patient 2 with sepsis-like picture, metabolic acidosis, and hyperammonemia were presented. Investigations revealed high propionylcarnitine (C3, elevated urinary methylmalonic acids, 3-hydroxypropionic acids and methylcitrate, consistent with MMA. Sanger-sequencing detected a homozygous novel mutation (c.329A>G; p.Y110C in the MUT gene in patient 1 and a heterozygous in parents. This mutation is predicted to have a damaging effect on the protein structure and function. In patient 2, we detected a novel homozygous nonsense mutation (c.2200C>T; p.Q734X and a heterozygous in parents. This mutation leads to a premature stop-codon at codon 734 of the MUT gene. We identified 2 novel mutations in the MUT gene causing isolated MMA.

  19. Several homozygous mutations in the gene for 11{beta}-hydroxysteroid dehydrogenase type 2 in patients with apparent mineralocorticoid excess

    Energy Technology Data Exchange (ETDEWEB)

    Wilson, R.C.; Harbison, M.D.; Hanauske-Abel, H.M.; Licholai, T. [New York Hospital-Cornell Medical Center, New York, NY (United States)] [and others

    1995-10-01

    Four deleterious mutations are described in the gene for HSD11B2, which encodes the type 2 isoenzyme of 11{beta}-hydroxysteroid dehydrogenase (11{beta}HSD2). In seven families with one or more members affected by apparent mineralocortiocoid excess, this disorder is shown to be the result of a deficiency in 11{beta}HSD2. Surprisingly, the patients are all homozygous for their mutation. This results from consanguinity in two families and possibly from endogamy or a founder effect in four of the other five families. The absence of compound heterozygotes remains to be investigated. 25 refs., 3 figs., 2 tabs.

  20. Mechanism for Mutational Inactivation of the Tumor Suppressor Smad2

    OpenAIRE

    Prunier, Celine; Ferrand, Nathalie; Frottier, Bertrand; Pessah, Marcia; Atfi, Azeddine

    2001-01-01

    Transforming growth factor β (TGF-β) is a potent natural antiproliferative agent that plays an important role in suppressing tumorigenicity. In numerous tumors, loss of TGF-β responsiveness is associated with inactivating mutations that can occur in components of this signaling pathway, such as the tumor suppressor Smad2. Although a general framework for how Smads transduce TGF-β signals has been proposed, the physiological relevance of alterations of Smad2 functions in promoting tumorigenesi...

  1. Elevated heart rate triggers action potential alternans and sudden death. translational study of a homozygous KCNH2 mutation.

    Directory of Open Access Journals (Sweden)

    Ulrich Schweigmann

    Full Text Available Long QT syndrome (LQTS leads to arrhythmic events and increased risk for sudden cardiac death (SCD. Homozygous KCNH2 mutations underlying LQTS-2 have previously been termed "human HERG knockout" and typically express severe phenotypes. We studied genotype-phenotype correlations of an LQTS type 2 mutation identified in the homozygous index patient from a consanguineous Turkish family after his brother died suddenly during febrile illness.Clinical work-up, DNA sequencing, mutagenesis, cell culture, patch-clamp, in silico mathematical modelling, protein biochemistry, confocal microscopy were performed. Genetic analysis revealed a homozygous C-terminal KCNH2 mutation (p.R835Q in the index patient (QTc ∼506 ms with notched T waves. Parents were I° cousins - both heterozygous for the mutation and clinically unremarkable (QTc ∼447 ms, father and ∼396 ms, mother. Heterologous expression of KCNH2-R835Q showed mildly reduced current amplitudes. Biophysical properties of ionic currents were also only nominally changed with slight acceleration of deactivation and more negative V50 in R835Q-currents. Protein biochemistry and confocal microscopy revealed similar expression patterns and trafficking of WT and R835Q, even at elevated temperature. In silico analysis demonstrated mildly prolonged ventricular action potential duration (APD compared to WT at a cycle length of 1000 ms. At a cycle length of 350 ms M-cell APD remained stable in WT, but displayed APD alternans in R835Q.Kv11.1 channels affected by the C-terminal R835Q mutation display mildly modified biophysical properties, but leads to M-cell APD alternans with elevated heart rate and could precipitate SCD under specific clinical circumstances associated with high heart rates.

  2. Costs of insensitive acetylcholinesterase insecticide resistance for the malaria vector Anopheles gambiae homozygous for the G119S mutation

    Directory of Open Access Journals (Sweden)

    Noel Valérie

    2010-01-01

    Full Text Available Abstract Background The G119S mutation responsible for insensitive acetylcholinesterase resistance to organophosphate and carbamate insecticides has recently been reported from natural populations of Anopheles gambiae in West Africa. These reports suggest there are costs of resistance associated with this mutation for An. gambiae, especially for homozygous individuals, and these costs could be influential in determining the frequency of carbamate resistance in these populations. Methods Life-history traits of the AcerKis and Kisumu strains of An. gambiae were compared following the manipulation of larval food availability in three separate experiments conducted in an insecticide-free laboratory environment. These two strains share the same genetic background, but differ in being homozygous for the presence or absence of the G119S mutation at the ace-1 locus, respectively. Results Pupae of the resistant strain were significantly more likely to die during pupation than those of the susceptible strain. Ages at pupation were significantly earlier for the resistant strain and their dry starved weights were significantly lighter; this difference in weight remained when the two strains were matched for ages at pupation. Conclusions The main cost of resistance found for An. gambiae mosquitoes homozygous for the G119S mutation was that they were significantly more likely to die during pupation than their susceptible counterparts, and they did so across a range of larval food conditions. Comparing the frequency of G119S in fourth instar larvae and adults emerging from the same populations would provide a way to test whether this cost of resistance is being expressed in natural populations of An. gambiae and influencing the dynamics of this resistance mutation.

  3. Homozygous MYH7 R1820W mutation results in recessive myosin storage myopathy: scapuloperoneal and respiratory weakness with dilated cardiomyopathy.

    Science.gov (United States)

    Yüceyar, Nur; Ayhan, Özgecan; Karasoy, Hatice; Tolun, Aslıhan

    2015-04-01

    Myosin storage myopathy (MSM) is a protein aggregate myopathy caused by the accumulation of myosin in muscle fibres and results from MYH7 mutation. Although MYH7 mutation is also an established cause of variable cardiomyopathy with or without skeletal myopathy, cardiomyopathy with MSM is a rare combination. Here, we update the clinical findings in the two brothers that we previously reported as having recessively inherited MSM characterized by scapuloperoneal distribution of weakness and typical hyaline-like bodies in type 1 muscle fibres. One of the patients, weak from childhood but not severely symptomatic until 28 years of age, had an unusual combination of MSM, severe dilated cardiomyopathy, and respiratory impairment at the age of 44 years. We identified homozygous missense mutation c.5458C>T (p.R1820W) in exon 37 in these patients as the second recessive MYH7 mutation reported to date. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. A homozygous nonsense mutation in the {beta}3 chain gene of laminin 5 (LAMB3) in herlitz junctional epidermolysis bullosa

    Energy Technology Data Exchange (ETDEWEB)

    Pulkkinen, L.; Christiano, A.M.; Uitto, J. [Thomas Jefferson Univ., Phildelphia, PA (United States)] [and others

    1994-11-15

    Herlitz junctional epidermolysis bullosa (H-JEB) is a severe autosomal recessive disorder characterized by blister formation within the dermal-epidermal basement membrane. Based on immunofluorescence analysis recognizing laminin 5 epitopes (previously known as nicein/kalinin), the genes for this lamina lucida protein have been proposed as candidate genes in H-JEB. Amplification of mRNA by RT-PCR, followed by direct nucleotide sequencing, revealed a homozygous C-to T transition resulting in a premature termination codon (CGA{r_arrow}TGA) on both alleles. This mutation was verified at the genomic DNA level, and both parents were shown to be heterozygous carriers of the same mutation. This is the first description of a mutation in the laminin {beta}3 chain gene (LAMB3) of laminin 5 in an H-JEB patient. 15 refs., 2 figs.

  5. Identification of a novel homozygous mutation (S144I) in a Malay patient with maple syrup urine disease.

    Science.gov (United States)

    Ali, Ernie Zuraida; Yunus, Zabedah Md; Desa, Norsiah Md; Hock, Ngu Lock

    2013-01-01

    Maple syrup urine disease (MSUD) is a rare autosomal recessive metabolic disorder of branched-chain amino acid metabolism caused by the defective function of branched-chain α-ketoacid dehydrogenase complex (BCKDH). It is characterised by increased plasma leucine, isoleucine, and valine levels, and mutations can be detected in any one of the BCKDHA, BCKDHB, and DBT genes. In this study, we describe the molecular basis of a novel mutation found in one MSUD Malay patient from consanguineous parents. A homozygous mutation has been detected in this patient whose both parents carried a heterozygous mutation at DNA coding region c.431G>T in exon 4, which resulted in a substitution of serine to isoleucine at codon 144 (p.S144I). In silico analysis predicted S144I to be potentially damaging. The mutation was located on the alpha helical region of the BCKDHA protein, and it is predicted to affect the stability of protein due to the loss of various polar interactions between local secondary structures. Homology analysis revealed that this mutation occurred in a highly conserved region (100%). This result indicates that S144I mutation is likely pathogenic and may contribute to the classic form of MSUD in this patient.

  6. Diffuse multicystic encephalomalacia in a preterm baby due to homozygous methylenetetrahydrofolate reductase 677 C-->T mutation.

    Science.gov (United States)

    Aygun, Canan; Tanyeri, Bilge; Ceyhan, Meltem; Bagci, Hasan; Kucukoduk, Sukru

    2008-06-01

    Methylenetetrahydrofolate reductase catalyzes the formation of 5-methyltetrahydrofolate from 5,10-methylentetrahydrofolate and produces folate for the methylation of homocysteine to methionine. Due to insufficient conversion of homocysteine to methionine, plasma homocysteine levels increase in methylenetetrahydrofolate reductase deficiency. Homocysteine is an amino acid that contains a neurotoxic sulfur molecule and can induce neuronal apoptosis. Methylenetetrahydrofolate reductase deficiency is 1 of the etiological factors that causes neurological symptoms and signs in the newborn and childhood period. Here, we report a premature baby with prenatal onset diffuse multicystic encephalomalacia and cerebellar atrophy due to homozygous methylenetetrahydrofolate reductase mutation.

  7. Phenotypes of Recessive Pediatric Cataract in a Cohort of Children with Identified Homozygous Gene Mutations (An American Ophthalmological Society Thesis)

    Science.gov (United States)

    Khan, Arif O.; Aldahmesh, Mohammed A.; Alkuraya, Fowzan S.

    2015-01-01

    Purpose: To assess for phenotype-genotype correlations in families with recessive pediatric cataract and identified gene mutations. Methods: Retrospective review (2004 through 2013) of 26 Saudi Arabian apparently nonsyndromic pediatric cataract families referred to one of the authors (A.O.K.) and for which recessive gene mutations were identified. Results: Fifteen different homozygous recessive gene mutations were identified in the 26 consanguineous families; two genes and five families are novel to this study. Ten families had a founder CRYBB1 deletion (all with bilateral central pulverulent cataract), two had the same missense mutation in CRYAB (both with bilateral juvenile cataract with marked variable expressivity), and two had different mutations in FYCO1 (both with bilateral posterior capsular abnormality). The remaining 12 families each had mutations in 12 different genes (CRYAA, CRYBA1, AKR1E2, AGK, BFSP2, CYP27A1, CYP51A1, EPHA2, GCNT2, LONP1, RNLS, WDR87) with unique phenotypes noted for CYP27A1 (bilateral juvenile fleck with anterior and/or posterior capsular cataract and later cerebrotendinous xanthomatosis), EPHA2 (bilateral anterior persistent fetal vasculature), and BFSP2 (bilateral flecklike with cloudy cortex). Potential carrier signs were documented for several families. Conclusions: In this recessive pediatric cataract case series most identified genes are noncrystallin. Recessive pediatric cataract phenotypes are generally nonspecific, but some notable phenotypes are distinct and associated with specific gene mutations. Marked variable expressivity can occur from a recessive missense CRYAB mutation. Genetic analysis of apparently isolated pediatric cataract can sometimes uncover mutations in a syndromic gene. Some gene mutations seem to be associated with apparent heterozygous carrier signs. PMID:26622071

  8. Phenotypes of Recessive Pediatric Cataract in a Cohort of Children with Identified Homozygous Gene Mutations (An American Ophthalmological Society Thesis).

    Science.gov (United States)

    Khan, Arif O; Aldahmesh, Mohammed A; Alkuraya, Fowzan S

    2015-01-01

    To assess for phenotype-genotype correlations in families with recessive pediatric cataract and identified gene mutations. Retrospective review (2004 through 2013) of 26 Saudi Arabian apparently nonsyndromic pediatric cataract families referred to one of the authors (A.O.K.) and for which recessive gene mutations were identified. Fifteen different homozygous recessive gene mutations were identified in the 26 consanguineous families; two genes and five families are novel to this study. Ten families had a founder CRYBB1 deletion (all with bilateral central pulverulent cataract), two had the same missense mutation in CRYAB (both with bilateral juvenile cataract with marked variable expressivity), and two had different mutations in FYCO1 (both with bilateral posterior capsular abnormality). The remaining 12 families each had mutations in 12 different genes (CRYAA, CRYBA1, AKR1E2, AGK, BFSP2, CYP27A1, CYP51A1, EPHA2, GCNT2, LONP1, RNLS, WDR87) with unique phenotypes noted for CYP27A1 (bilateral juvenile fleck with anterior and/or posterior capsular cataract and later cerebrotendinous xanthomatosis), EPHA2 (bilateral anterior persistent fetal vasculature), and BFSP2 (bilateral flecklike with cloudy cortex). Potential carrier signs were documented for several families. In this recessive pediatric cataract case series most identified genes are noncrystallin. Recessive pediatric cataract phenotypes are generally nonspecific, but some notable phenotypes are distinct and associated with specific gene mutations. Marked variable expressivity can occur from a recessive missense CRYAB mutation. Genetic analysis of apparently isolated pediatric cataract can sometimes uncover mutations in a syndromic gene. Some gene mutations seem to be associated with apparent heterozygous carrier signs.

  9. Homozygosity mapping and whole exome sequencing reveal a novel homozygous COL18A1 mutation causing Knobloch syndrome.

    Directory of Open Access Journals (Sweden)

    Alireza Haghighi

    Full Text Available The aim of this study was to identify the genetic basis of a chorioretinal dystrophy with high myopia of unknown origin in a child of a consanguineous marriage. The proband and ten family members of Iranian ancestry participated in this study. Linkage analysis was carried out with DNA samples of the proband and her parents by using the Human SNP Array 6.0. Whole exome sequencing (WES was performed with the patients' DNA. Specific sequence alterations within the homozygous regions identified by whole exome sequencing were verified by Sanger sequencing. Upon genetic analysis, a novel homozygous frameshift mutation was found in exon 42 of the COL18A1 gene in the patient. Both parents were heterozygous for this sequence variation. Mutations in COL18A1 are known to cause Knobloch syndrome (KS. Retrospective analysis of clinical records of the patient revealed surgical removal of a meningocele present at birth. The clinical features shown by our patient were typical of KS with the exception of chorioretinal degeneration which is a rare manifestation. This is the first case of KS reported in a family of Iranian ancestry. We identified a novel disease-causing (deletion mutation in the COL18A1 gene leading to a frameshift and premature stop codon in the last exon. The mutation was not present in SNP databases and was also not found in 192 control individuals. Its localization within the endostatin domain implicates a functional relevance of endostatin in KS. A combined approach of linkage analysis and WES led to a rapid identification of the disease-causing mutation even though the clinical description was not completely clear at the beginning.

  10. Krüppel-like factor 1 mutations and expression of hemoglobins F and A2 in homozygous hemoglobin E syndrome.

    Science.gov (United States)

    Tepakhan, Wanicha; Yamsri, Supawadee; Fucharoen, Goonnapa; Sanchaisuriya, Kanokwan; Fucharoen, Supan

    2015-07-01

    The basis for variability of hemoglobin (Hb) F in homozygous Hb E disease is not well understood. We have examined multiple mutations of the Krüppel-like factor 1 (KLF1) gene; an erythroid specific transcription factor and determined their associations with Hbs F and A2 expression in homozygous Hb E. Four KLF1 mutations including G176AfsX179, T334R, R238H, and -154 (C-T) were screened using specific PCR assays on 461 subjects with homozygous Hb E and 100 normal controls. None of these four mutations were observed in 100 normal controls. Among 461 subjects with homozygous Hb E, 306 had high (≥5 %) and 155 had low (<5 %) Hb F. DNA analysis identified the KLF1 mutations in 35 cases of the former group with high Hb F, including the G176AfsX179 mutation (17/306 = 5.6 %), T334R mutation (9/306 = 2.9 %), -154 (C-T) mutation (7/306 = 2.3 %), and R328H mutation (2/306 = 0.7 %). Only two subjects in the latter group with low Hb F carried the G176AfsX179 and -154 (C-T) mutations. Significant higher Hb A2 level was observed in those of homozygous Hb E with the G176AfsX179 mutation as compared to those without KLF1 mutations. These results indicate that KLF1 is among the genetic factors associated with increased Hbs F and A2, and in combination with other factors could explain the variabilities of these Hb expression in Hb E syndrome.

  11. A homozygous nonsense CEP250 mutation combined with a heterozygous nonsense C2orf71 mutation is associated with atypical Usher syndrome.

    Science.gov (United States)

    Khateb, Samer; Zelinger, Lina; Mizrahi-Meissonnier, Liliana; Ayuso, Carmen; Koenekoop, Robert K; Laxer, Uri; Gross, Menachem; Banin, Eyal; Sharon, Dror

    2014-07-01

    Usher syndrome (USH) is a heterogeneous group of inherited retinitis pigmentosa (RP) and sensorineural hearing loss (SNHL) caused by mutations in at least 12 genes. Our aim is to identify additional USH-related genes. Clinical examination included visual acuity test, funduscopy and electroretinography. Genetic analysis included homozygosity mapping and whole exome sequencing (WES). A combination of homozygosity mapping and WES in a large consanguineous family of Iranian Jewish origin revealed nonsense mutations in two ciliary genes: c.3289C>T (p.Q1097*) in C2orf71 and c.3463C>T (p.R1155*) in centrosome-associated protein CEP250 (C-Nap1). The latter has not been associated with any inherited disease and the c.3463C>T mutation was absent in control chromosomes. Patients who were double homozygotes had SNHL accompanied by early-onset and severe RP, while patients who were homozygous for the CEP250 mutation and carried a single mutant C2orf71 allele had SNHL with mild retinal degeneration. No ciliary structural abnormalities in the respiratory system were evident by electron microscopy analysis. CEP250 expression analysis of the mutant allele revealed the generation of a truncated protein lacking the NEK2-phosphorylation region. A homozygous nonsense CEP250 mutation, in combination with a heterozygous C2orf71 nonsense mutation, causes an atypical form of USH, characterised by early-onset SNHL and a relatively mild RP. The severe retinal involvement in the double homozygotes indicates an additive effect caused by nonsense mutations in genes encoding ciliary proteins. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

  12. Homozygous mutation in Atlastin GTPase 1 causes recessive hereditary spastic paraplegia.

    Science.gov (United States)

    Willkomm, Lena; Heredia, Raul; Hoffmann, Katrin; Wang, Haicui; Voit, Thomas; Hoffman, Eric P; Cirak, Sebahattin

    2016-06-01

    Hereditary spastic paraplegia (HSP) is an extremely heterogeneous disease caused by mutations of numerous genes leading to lower limb spasticity (pure forms) that can be accompanied by neurological symptoms (complex forms). Despite recent advances, many causal mutations in patients remain unknown. We identified a consanguineous family with the early-onset HSP. Whole-exome sequencing revealed homozygosity for a novel Atlastin GTPase 1 gene stop mutation in three affected siblings. Heterozygous parents and siblings were unaffected. This was unexpected as mutations in the Atlastin 1 gene are known to cause autosomal dominant HSP. But our study showed that Atlastin 1 mutations may cause autosomal recessively inherited paraplegia with an underlying loss-of-function mechanism. Hence, patients with recessive forms of HSP should also be tested for the Atlastin 1 gene.

  13. A homozygous MSH6 mutation in a child with café-au-lait spots, oligodendroglioma and rectal cancer.

    Science.gov (United States)

    Menko, Fred H; Kaspers, Gertjan L; Meijer, Gerrit A; Claes, Kathleen; van Hagen, Johanna M; Gille, Johan J P

    2004-01-01

    Hereditary nonpolyposis colorectal cancer (HNPCC) is an autosomal dominant condition due to heterozygous germline mutations in DNA mismatch repair genes, in particular MLH1, MSH2 and MSH6. Recently, a syndrome was recognized in which children develop haematological malignancies, solid tumours and signs of neurofibromatosis type 1 due to bi-allelic MMR gene mutations in MLH1, MSH2 and PMS2. Here we describe the child of healthy consanguineous parents who had café-au-lait spots, oligodendroglioma, and rectal cancer. The patient was homozygous for the MSH6 mutation c.3386_3388delGTG in exon 5 which has a predicted pathogenic effect. Germline NF1 gene mutation testing was negative. The rectal tumour showed microsatellite instability and absence of MSH6 staining, whereas the brain tumour was MSI stable and showed normal immunohistochemical expression of MSH6. Apparently, not only MLH1, MSH2 and PMS2, but also MSH6 is involved in the syndrome of childhood cancer and signs of neurofibromatosis type 1.

  14. A Homozygous Mutation in GPT2 Associated with Nonsyndromic Intellectual Disability in a Consanguineous Family from Costa Rica.

    Science.gov (United States)

    Lobo-Prada, Tanya; Sticht, Heinrich; Bogantes-Ledezma, Sixto; Ekici, Arif; Uebe, Steffen; Reis, André; Leal, Alejandro

    2017-01-28

    Intellectual disability is a highly heterogeneous disease that affects the central nervous system and impairs patients' ability to function independently. Despite multiples genes involved in the etiology of disease, most of the genetic background is yet to be discovered. We used runs of homozygosity and exome sequencing to study a large Costa Rican family with four individuals affected with severe intellectual disability and found a novel homozygous missense mutation, p. 96G>R, c. 286G>A, in all affected individuals. This gene encodes for a pyridoxal enzyme involved in the production of the neurotransmitter glutamate and is highly expressed in the white matter of brain and cerebellum. Protein modeling of GPT2 predicted that the mutation is located in a loop where the substrate binds to the active site of the enzyme, therefore, suggesting that the catalytic activity is impaired. With our report of a second mutation we fortify the importance of GPT2 as a novel cause of autosomal recessive nonsyndromic intellectual disability and support the premise that GPT2 is highly important for the neurodevelopment of the central nervous system. The mutation p. 96G>R c. 286G>A in GPT2, located in a loop where the substrate binds to the active site of the enzyme, fortifies the importance of GPT2 in the pathogenesis of nonsyndromic intellectual disability.

  15. Homozygous FOXE3 mutations cause non-syndromic, bilateral, total sclerocornea, aphakia, microphthalmia and optic disc coloboma.

    Science.gov (United States)

    Ali, Manir; Buentello-Volante, Beatriz; McKibbin, Martin; Rocha-Medina, J Alberto; Fernandez-Fuentes, Narcis; Koga-Nakamura, Wilson; Ashiq, Aruna; Khan, Kamron; Booth, Adam P; Williams, Grange; Raashid, Yasmin; Jafri, Hussain; Rice, Aine; Inglehearn, Chris F; Zenteno, Juan Carlos

    2010-06-23

    To investigate the genetic basis of recessively-inherited congenital, non syndromic, bilateral, total sclerocornea in two consanguineous pedigrees, one from the Punjab province of Pakistan and the other from the Tlaxcala province of Mexico. Ophthalmic examinations were conducted on each family member to confirm their diagnosis and magnetic resonance imaging (MRI) or ultrasonography of the eyes was performed on some family members. Genomic DNA was analyzed by homozygosity mapping using the Affymetrix 6.0 SNP array and linkage was confirmed with polymorphic microsatellite markers. Candidate genes were sequenced. A diagnosis of autosomal recessive sclerocornea was established for 7 members of the Pakistani and 8 members of the Mexican pedigrees. In the Pakistani family we established linkage to a region on chromosome 1p that contained Forkhead Box E3 (FOXE3), a strong candidate gene since FOXE3 mutations had previously been associated with various anterior segment abnormalities. Sequencing FOXE3 identified the previously reported nonsense mutation, c.720C>A, p.C240X, in the Pakistani pedigree and a novel missense mutation which disrupts an evolutionarily conserved residue in the forkhead domain, c.292T>C, p.Y98H, in the Mexican pedigree. Individuals with heterozygous mutations had no ocular abnormalities. MRI or ultrasonography confirmed that the patients with sclerocornea were also aphakic, had microphthalmia and some had optic disc coloboma. This is the fourth report detailing homozygous FOXE3 mutations causing anterior segment abnormalities in human patients. Previous papers have emphasized aphakia and microphthalmia as the primary phenotype, but we find that the initial diagnosis - and perhaps the only one possible in a rural setting - is one of non-syndromic, bilateral, total sclerocornea. Dominantly inherited anterior segment defects have also been noted in association with heterozygous FOXE3 mutations. However the absence of any abnormalities in the FOXE3

  16. Homozygous mutation of focal adhesion kinase in embryonic stem cell derived neurons: normal electrophysiological and morphological properties in vitro

    Directory of Open Access Journals (Sweden)

    Komiyama NH

    2006-06-01

    Full Text Available Abstract Background Genetically manipulated embryonic stem (ES cell derived neurons (ESNs provide a powerful system with which to study the consequences of gene manipulation in mature, synaptically connected neurons in vitro. Here we report a study of focal adhesion kinase (FAK, which has been implicated in synapse formation and regulation of ion channels, using the ESN system to circumvent the embryonic lethality of homozygous FAK mutant mice. Results Mouse ES cells carrying homozygous null mutations (FAK-/- were generated and differentiated in vitro into neurons. FAK-/- ESNs extended axons and dendrites and formed morphologically and electrophysiologically intact synapses. A detailed study of NMDA receptor gated currents and voltage sensitive calcium currents revealed no difference in their magnitude, or modulation by tyrosine kinases. Conclusion FAK does not have an obligatory role in neuronal differentiation, synapse formation or the expression of NMDA receptor or voltage-gated calcium currents under the conditions used in this study. The use of genetically modified ESNs has great potential for rapidly and effectively examining the consequences of neuronal gene manipulation and is complementary to mouse studies.

  17. Exclusion of homozygous PLCE1 (NPHS3) mutations in 69 families with idiopathic and hereditary FSGS.

    LENUS (Irish Health Repository)

    Gbadegesin, Rasheed

    2009-02-01

    Focal and segmental glomerulosclerosis (FSGS) is the most common glomerular cause of end-stage kidney disease (ESKD). Although the etiology of FSGS has not been fully elucidated, recent results from the positional cloning of genes mutated in nephrotic syndromes are now beginning to provide insight into the pathogenesis of these diseases. Mutations in PLCE1\\/NPHS3 have recently been reported as a cause of nephrotic syndrome characterized by diffuse mesangial sclerosis (DMS) histology. One single family with a missense mutation had late onset of the disease that was characterized by FSGS. To further define the role of PLCE1 mutations in the etiology of FSGS, we performed mutational analysis in 69 families with FSGS. A total of 69 families with 231 affected individuals were examined. The median age of disease onset was 26 years (range 1-66 years). Onset of ESKD was at a median age of 35.5 years. Seven variants leading to non-synonymous changes were found, of which only two are new variants (exon 4 c.1682 G>A R561Q, exon 31 c.6518A>G K2173R). No known disease-causing mutations were identified in the families screened. PLCE1\\/NPHS3 mutations are not a cause of FSGS in this cohort. The absence of mutations in PLCE1\\/NPHS3 in this study indicates that there are additional genetic causes of FSGS and that hereditary FSGS is a heterogeneous disease. Kindreds appropriate for genome-wide screening are currently being subjected to analysis with the aim of identifying other genetic causes of FSGS.

  18. A novel ZRS mutation leads to preaxial polydactyly type 2 in a heterozygous form and Werner mesomelic syndrome in a homozygous form.

    Science.gov (United States)

    VanderMeer, Julia E; Lozano, Reymundo; Sun, Miao; Xue, Yuan; Daentl, Donna; Jabs, Ethylin Wang; Wilcox, William R; Ahituv, Nadav

    2014-08-01

    Point mutations in the zone of polarizing activity regulatory sequence (ZRS) are known to cause human limb malformations. Although most mutations cause preaxial polydactyly (PPD), triphalangeal thumb (TPT) or both, a mutation in position 404 of the ZRS causes more severe Werner mesomelic syndrome (WMS) for which malformations include the distal arm or leg bones in addition to the hands and/or feet. Of more than 15 reported families with ZRS mutations, only one homozygous individual has been reported, with no change in phenotype compared with heterozygotes. Here, we describe a novel point mutation in the ZRS, 402C>T (AC007097.4:g.105548C>T), that is transmitted through two Mexican families with one homozygous individual. The homozygous phenotype for this mutation, WMS, is more severe than the numerous heterozygous individuals genotyped from both families who have TPT and PPD. A mouse transgenic enhancer assay shows that this mutation causes an expansion of the enhancer's expression domain in the developing mouse limb, confirming its pathogenicity. Combined, our results identify a novel ZRS mutation in the Mexican population, 402C>T, and suggest that a dosage effect exists for this ZRS mutation. © 2014 WILEY PERIODICALS, INC.

  19. Generalized pustular psoriasis in a 92-year-old man with a homozygous nonsense mutation in IL36RN.

    Science.gov (United States)

    Ueda, Yoshitaka; Komine, Mayumi; Kamiya, Koji; Tsuda, Hidetoshi; Maekawa, Takeo; Murata, Satoru; Ohtsuki, Mamitaro

    2017-12-07

    A 92-year-old man developed an erythematous eruption on the trunk and extremities with numerous pustules accompanied by fever. He had never experienced pustular eruption or been diagnosed with psoriasis previously. Skin biopsy revealed Kogoj's spongiform pustule, and he was diagnosed with generalized pustular psoriasis (GPP). Genomic DNA was extracted from his peripheral blood and the sequence of IL36RN gene was analyzed, which revealed a p.Arg10X homozygous mutation. Several cases of elderly-onset GPP have been reported, however, this is the oldest case of GPP. The existence of splice variants of IL36RN was suspected, but we could not detect any splice variants of IL36RN in this case or in a healthy control from peripheral blood samples. © 2017 Japanese Dermatological Association.

  20. Generation of an Abcc8 homozygous mutation human embryonic stem cell line using CRISPR/Cas9.

    Science.gov (United States)

    Guo, Dongsheng; Liu, Haikun; Gao, Ge; Ruzi, Aynisahan; Wang, Kepin; Wu, Han; Lai, Keyu; Liu, Yanli; Yang, Fan; Lai, Liangxue; Li, Yin-Xiong

    2016-11-01

    The gene of ATP-binding cassette subfamily C member 8 (Abcc8) is cytogenetically located at 11p15.1 and encodes the sulfonylurea receptor (SUR1). SUR1 is a subunit of ATP-sensitive potassium channel (KAPT) in the β-cell regulating insulin secretion. Mutations of ABCC8 are responsible for congenital hyperinsulinism (CHI). Here we generated an Abcc8 homozygous mutant cell line by CRISPR/Cas9 technique with 22bp deletion resulting in abnormal splicing on human embryonic stem cell line H1. The phenotypic characteristics of this cell line reveal defective KATP channel and diazoxide-unresponsive that provides an ideal model for molecular pathology research and drug screening for CHI. Copyright © 2016 Michael Boutros, German Cancer Research Center, Heidelberg, Germany. Published by Elsevier B.V. All rights reserved.

  1. Homozygous Nonsense Mutations in KIAA1279 Are Associated with Malformations of the Central and Enteric Nervous Systems

    Science.gov (United States)

    Brooks, Alice S. ; Bertoli-Avella, Aida M. ; Burzynski, Grzegorz M. ; Breedveld, Guido J. ; Osinga, Jan ; Boven, Ludolf G. ; Hurst, Jane A. ; Mancini, Grazia M. S. ; Lequin, Maarten H. ; de Coo, Rene F. ; Matera, Ivana ; de Graaff, Esther ; Meijers, Carel ; Willems, Patrick J. ; Tibboel, Dick ; Oostra, Ben A. ; Hofstra, Robert M. W. 

    2005-01-01

    We identified, by homozygosity mapping, a novel locus on 10q21.3-q22.1 for Goldberg-Shprintzen syndrome (GOSHS) in a consanguineous Moroccan family. Phenotypic features of GOSHS in this inbred family included microcephaly and mental retardation, which are both central nervous system defects, as well as Hirschsprung disease, an enteric nervous system defect. Furthermore, since bilateral generalized polymicogyria was diagnosed in all patients in this family, this feature might also be considered a key feature of the syndrome. We demonstrate that homozygous nonsense mutations in KIAA1279 at 10q22.1, encoding a protein with two tetratrico peptide repeats, underlie this syndromic form of Hirschsprung disease and generalized polymicrogyria, establishing the importance of KIAA1279 in both enteric and central nervous system development. PMID:15883926

  2. A Novel Homozygous Frameshift Mutation in Exon 2 of Gene Associated with Severe Obesity: A Case Report

    Directory of Open Access Journals (Sweden)

    Ashwaq Shukri Altawil

    2016-01-01

    Full Text Available Background Monogenic obesity is a rare type of obesity caused by a mutation in a single gene. Patients with monogenic obesity may develop early onset of obesity and severe metabolic abnormalities. Case Presentation A two-and-half-year-old girl was presented to our clinic because of excessive weight gain and hyperphagia. She was born at full term, by normal vaginal delivery with birth weight of 2.82 kg and no complications during pregnancy. The patient was the second child of two healthy, non-obese Saudis with known consanguinity. She gained weight rapidly leading to obesity at the age of three months. Methods The demographic data and clinical features were recorded. Blood samples were collected and tested for endocrine and metabolic characteristics and genetic studies. Mutations of the LEP gene were screened. The coding exons 2 and 3 and the corresponding exon–intron boundaries were amplified by polymerase chain reaction using specific primers, analyzed by direct sequencing using an ABI sequencer 3500 xL GA (Applied Biosystems, and evaluated using the JSI SeqPilot software. The resulting sequence data were compared with the reference MM_0002302. Conclusion We report a novel homozygous frameshift mutation c.144delin TAC (G1n49Thrfs * 23 in exon 2 of the LEP gene associated with extreme obesity.

  3. Charcot-Marie-Tooth disease type 2 caused by homozygous MME gene mutation superimposed by chronic inflammatory demyelinating polyneuropathy.

    Science.gov (United States)

    Fujisawa, Miwako; Sano, Yasuteru; Omoto, Masatoshi; Ogasawara, Jyun-Ichi; Koga, Michiaki; Takashima, Hiroshi; Kanda, Takashi

    2017-09-30

    We report a 59-year-old Japanese male who developed gradually worsening weakness and numbness of distal four extremities since age 50. His parents were first cousins, and blood and cerebral spinal examinations were unremarkable. Homozygous mutation of MME gene was detected and thus he was diagnosed as autosomal-recessive Charcot-Marie-Tooth disease 2T (AR-CMT2T); however, electrophysiological examinations revealed scattered demyelinative changes including elongated terminal latency in several peripheral nerve trunks. Sural nerve biopsy showed endoneurial edema and a lot of thinly myelinated nerve fibers with uneven distribution of remnant myelinated fibers within and between fascicles. Immunoglobulin treatment was initiated considering the possibility of superimposed inflammation and demyelination, and immediate clinical as well as electrophysiological improvements were noted. Our findings indicate that AR-CMT2T caused by MME mutation predisposes to a superimposed inflammatory demyelinating neuropathy. This is the first report which documented the co-existence of CMT2 and chronic inflammatory demyelinating polyneuropathy (CIDP); however, in the peripheral nervous system, neprilysin, a product of MME gene, is more abundant in myelin sheath than in axonal component. The fragility of myelin sheath due to mutated neprilysin may trigger the detrimental immune response against peripheral myelin in this patient.

  4. A Novel Homozygous Frameshift Mutation in Exon 2 of LEP Gene Associated with Severe Obesity: A Case Report.

    Science.gov (United States)

    Altawil, Ashwaq Shukri; Mawlawi, Horia Ahmad; Alghamdi, Khalid Ateeq; Almijmaj, Faten Fohaid

    2016-01-01

    Monogenic obesity is a rare type of obesity caused by a mutation in a single gene. Patients with monogenic obesity may develop early onset of obesity and severe metabolic abnormalities. A two-and-half-year-old girl was presented to our clinic because of excessive weight gain and hyperphagia. She was born at full term, by normal vaginal delivery with birth weight of 2.82 kg and no complications during pregnancy. The patient was the second child of two healthy, non-obese Saudis with known consanguinity. She gained weight rapidly leading to obesity at the age of three months. The demographic data and clinical features were recorded. Blood samples were collected and tested for endocrine and metabolic characteristics and genetic studies. Mutations of the LEP gene were screened. The coding exons 2 and 3 and the corresponding exon-intron boundaries were amplified by polymerase chain reaction using specific primers, analyzed by direct sequencing using an ABI sequencer 3500 xL GA (Applied Biosystems), and evaluated using the JSI SeqPilot software. The resulting sequence data were compared with the reference MM_0002302. We report a novel homozygous frameshift mutation c.144delin TAC (G1n49Thrfs*23) in exon 2 of the LEP gene associated with extreme obesity.

  5. Novel homozygous RARS2 mutation in two siblings without pontocerebellar hypoplasia – further expansion of the phenotypic spectrum

    Directory of Open Access Journals (Sweden)

    S. Lühl

    2016-10-01

    Full Text Available Abstract Background Pontocerebellar hypoplasia type 6 (PCH6 is a mitochondrial disease caused by mutations in the RARS2 gene. RARS2 encodes mitochondrial arginyl transfer RNA synthetase, an enzyme involved in mitochondrial protein translation. A total of 27 patients from 14 families have been reported so far. Characteristic clinical features comprise neonatal lactic acidosis, severe encephalopathy, intractable seizures, feeding problems and profound developmental delay. Most patients show typical neuroradiologic abnormalities including cerebellar hypoplasia and progressive pontocerebellar atrophy. Methods We describe the clinical, biochemical and molecular features of 2 siblings with a novel homozygous mutation in RARS2. Both patients presented neonatally with lactic acidosis. While the older sibling had severe neurological symptoms with microcephaly, seizures and developmental delay, the younger patient was still neurologically asymptomatic at the age of 2 months. Results MRI studies in both children lacked pontocerebellar involvement. The expression of the OXPHOS complex proteins was decreased in both patients, whereas oxygen consumption was increased. Conclusions Characteristic neuroradiological abnormalities of PCH6 such as vermis and cerebellar hypoplasia and progressive pontocerebellar atrophy may be missing in patients with RARS2 mutations. RARS2 testing should therefore also be performed in patients without pontocerebellar hypoplasia but otherwise typical clinical symptoms.

  6. The Phenotype and Outcome of Infantile Cardiomyopathy Caused by a Homozygous ELAC2 Mutation.

    Science.gov (United States)

    Shinwari, Zarghuna M A; Almesned, Abdulrahman; Alakhfash, Ali; Al-Rashdan, Ahmad M; Faqeih, Eissa; Al-Humaidi, Zainab; Alomrani, Ahmed; Alghamdi, Malak; Colak, Dilek; Alwadai, Abdullah; Rababh, Monther; Al-Fayyadh, Majid; Al-Hassnan, Zuhair N

    2017-01-01

    Cardiomyopathy (CMP) in children is a clinically and genetically heterogeneous group of disorders. Disease-associated mutations have been identified in more than 50 genes. Recently, mutations in the mitochondrial tRNA processing gene, ELAC2, were reported to be associated with the recessively inherited form of hypertrophic CMP (HCM). This study is aimed at describing the cardiac phenotype and outcome of ELAC2 mutation. We performed whole exome sequencing followed by targeted mutation screening to identify the genetic etiology of severe infantile-onset CMP in 64 consanguineous Saudi families. A previously reported mutation (p.Phe154Leu) in ELAC2 gene was detected in 16 families. The index cases presented between 2 and 7 months of age with HCM in 13 infants and dilated CMP (DCM) in 3. Pericardial effusion was observed in 7 infants (44%). All infants died with a median age of death of 4 months. Almost 1/3 of them died during the initial presentation. Our study suggests screening the ELAC2 gene in severe infantile-onset HCM or DCM of unknown etiology, especially in the presence of pericardial effusion. Our work demonstrates a universally poor outcome of the (p.Phe154Leu) variant in ELAC2 gene; a correlation that helps in counseling parents and in planning appropriate medical intervention. © 2017 S. Karger AG, Basel.

  7. Mechanism for Mutational Inactivation of the Tumor Suppressor Smad2

    Science.gov (United States)

    Prunier, Celine; Ferrand, Nathalie; Frottier, Bertrand; Pessah, Marcia; Atfi, Azeddine

    2001-01-01

    Transforming growth factor β (TGF-β) is a potent natural antiproliferative agent that plays an important role in suppressing tumorigenicity. In numerous tumors, loss of TGF-β responsiveness is associated with inactivating mutations that can occur in components of this signaling pathway, such as the tumor suppressor Smad2. Although a general framework for how Smads transduce TGF-β signals has been proposed, the physiological relevance of alterations of Smad2 functions in promoting tumorigenesis is still unknown. Here, we show that expression of Smad2.P445H, a tumor-derived mutation of Smad2 found in human cancer, suppresses the ability of the Smads to mediate TGF-β-induced growth arrest and transcriptional responses. Smad2.P445H is phosphorylated by the activated TGF-β receptor at the carboxy-terminal serine residues and associates with Smad3 and Smad4 but is unable to dissociate from the receptor. Upon ligand-induced phosphorylation, Smad2.P445H interacts stably with wild-type Smad2, thereby blocking TGF-β-induced nuclear accumulation of wild-type Smad2 and Smad2-dependent transcription. The ability of the Smad2.P445H to block the nuclear accumulation of wild-type Smad2 protein reveals a new mechanism for loss of sensitivity to the growth-inhibitory functions of TGF-β in tumor development. PMID:11313456

  8. Elevated homocysteine, glutathione and cysteinylglycine concentrations in patients homozygous for the Chuvash polycythemia VHL mutation

    Science.gov (United States)

    Sergueeva, Adelina I.; Miasnikova, Galina Y.; Okhotin, Daniel J.; Levina, Alla A.; Debebe, Zufan; Ammosova, Tatiana; Niu, Xiaomei; Romanova, Elena A.; Nekhai, Sergei; DiBello, Patricia M.; Jacobsen, Donald W.; Prchal, Josef T.; Gordeuk, Victor R.

    2010-01-01

    In Chuvash polycythemia, homozygous von Hippel-Lindau (VHL) 598C>T leads to increased hypoxia inducible factor-1α and 2α, thromboses and lower systemic blood pressures. Circulating homocysteine, glutathione, γ-glutamyltransferase and cysteinylglycine concentrations were higher in 34 VHL598C>T homozygotes than in 37 normal controls and cysteine was lower. Multivariate analysis showed elevated homocysteine independently associated with higher mean systemic blood pressures and elevated glutathione was associated with lower pressures to a similar degree. Among VHL598C>T homozygotes, homocysteine was elevated with low and normal folate concentrations, consistent with a possible defect in the remethylation pathway. The elevated glutathione and γ-glutamyltranserase levels correlated positively with cysteinylglycine, consistent with possible upregulation of a glutathione synthetic enzyme and γ-glutamyltransferase. Cysteinylglycine correlated inversely with cysteine, consistent with possible reduced cysteinyldipeptidase activity. We conclude that up-regulated hypoxia-sensing may influence multiple steps in thiol metabolism. The effects of the resultant elevated levels of homocysteine and glutathione on systemic blood pressure may largely balance each other out. PMID:18223282

  9. A Novel Homozygous Mutation in FOXC1 Causes Axenfeld Rieger Syndrome with Congenital Glaucoma

    NARCIS (Netherlands)

    Micheal, S.; Siddiqui, S.N.; Zafar, S.N.; Villanueva-Mendoza, C.; Cortes-Gonzalez, V.; Khan, M.I.; Hollander, A.I. den

    2016-01-01

    BACKGROUND: Anterior segment dysgenesis (ASD) disorders are a group of clinically and genetically heterogeneous phenotypes in which frequently cornea, iris, and lens are affected. This study aimed to identify novel mutations in PAX6, PITX2 and FOXC1 in families with anterior segment dysgenesis

  10. A homozygous missense mutation in the IRBP gene (RBP3) associated with autosomal recessive retinitis pigmentosa.

    NARCIS (Netherlands)

    Hollander, A.I. den; McGee, T.L.; Ziviello, C.; Banfi, S.; Dryja, T.P.; Gonzalez-Fernandez, F.; Ghosh, D.; Berson, E.L.

    2009-01-01

    PURPOSE: Interphotoreceptor retinoid-binding protein (IRBP) has been considered essential for normal rod and cone function, as it mediates the transport of retinoids between the photoreceptors and the retinal pigment epithelium. This study was performed to determine whether mutations in the IRBP

  11. 46,XY Gonadal Dysgenesis due to a Homozygous Mutation in Desert Hedgehog (DHH) Identified by Exome Sequencing.

    Science.gov (United States)

    Werner, Ralf; Merz, Hartmut; Birnbaum, Wiebke; Marshall, Louise; Schröder, Tatjana; Reiz, Benedikt; Kavran, Jennifer M; Bäumer, Tobias; Capetian, Philipp; Hiort, Olaf

    2015-07-01

    46,XY disorders of sex development (DSD) comprise a heterogeneous group of congenital conditions. Mutations in a variety of genes can affect gonadal development or androgen biosynthesis/action and thereby influence the development of the internal and external genital organs. The objective of the study was to identify the genetic cause in two 46,XY sisters of a consanguineous family with DSD and gonadal tumor formation. We used a next-generation sequencing approach by exome sequencing. Electrophysiological and high-resolution ultrasound examination of peripheral nerves as well as histopathological examination of the gonads were performed. We identified a novel homozygous R124Q mutation in the desert hedgehog gene (DHH), which alters a conserved residue among the three mammalian Hedgehog ligands sonic hedgehog, Indian hedgehog, and desert hedgehog. No other relevant mutations in DSD-related genes were encountered. The gonads of one patient showed partial gonadal dysgenesis with loss of Leydig cells in tubular areas with seminoma in situ and a hyperplasia of Leydig cell-like cells expressing CYP17A1 in more dysgenetic parts of the gonad. In addition, both patients suffer from a polyneuropathy. High-resolution ultrasound revealed a structural change of peripheral nerve structure that fits well to a minifascicle formation of peripheral nerves. Mutations in DHH play a role in 46,XY gonadal dysgenesis and are associated with seminoma formation and a neuropathy with minifascicle formation. Gonadal dysgenesis in these cases may be due to impairment of Sertoli cell-Leydig cell interaction during gonadal development.

  12. High proportion of genetic cases in patients with advanced cardiomyopathy including a novel homozygous Plakophilin 2-gene mutation.

    Directory of Open Access Journals (Sweden)

    Baerbel Klauke

    Full Text Available Cardiomyopathies might lead to end-stage heart disease with the requirement of drastic treatments like bridging up to transplant or heart transplantation. A not precisely known proportion of these diseases are genetically determined. We genotyped 43 index-patients (30 DCM, 10 ARVC, 3 RCM with advanced or end stage cardiomyopathy using a gene panel which covered 46 known cardiomyopathy disease genes. Fifty-three variants with possible impact on disease in 33 patients were identified. Of these 27 (51% were classified as likely pathogenic or pathogenic in the MYH7, MYL2, MYL3, NEXN, TNNC1, TNNI3, DES, LMNA, PKP2, PLN, RBM20, TTN, and CRYAB genes. Fifty-six percent (n = 24 of index-patients carried a likely pathogenic or pathogenic mutation. Of these 75% (n = 18 were familial and 25% (n = 6 sporadic cases. However, severe cardiomyopathy seemed to be not characterized by a specific mutation profile. Remarkably, we identified a novel homozygous PKP2-missense variant in a large consanguineous family with sudden death in early childhood and several members with heart transplantation in adolescent age.

  13. A homozygous frameshift mutation in the HOXC13 gene underlies pure hair and nail ectodermal dysplasia in a Syrian family.

    Science.gov (United States)

    Farooq, Muhammad; Kurban, Mazen; Fujimoto, Atsushi; Fujikawa, Hiroki; Abbas, Ossama; Nemer, Georges; Saliba, Jessica; Sleiman, Rima; Tofaili, Mona; Kibbi, Abdul-Ghani; Ito, Masaaki; Shimomura, Yutaka

    2013-04-01

    Pure hair and nail ectodermal dysplasia (PHNED) is a rare genetic disorder characterized by hypotrichosis or complete alopecia, as well as nail dystrophy. Mutations in the type II hair keratin gene KRT85 and the HOXC13 gene on chromosome 12q have recently been identified in families with autosomal-recessive PHNED. In the present study, we have analyzed a consanguineous Syrian family with an affected girl having complete alopecia and nail dystrophy since birth. The family clearly showed linkage to chromosome 12q13.13-12q14.3, which excluded the KRT85 gene. Sequencing of another candidate gene HOXC13 within the linkage interval identified a homozygous frameshift mutation (c.355delC; p.Leu119Trpfs*20). Expression studies in cultured cells revealed that the mutant HOXC13 protein mislocalized within the cytoplasm, and failed to upregulate the promoter activities of its target genes. Our results strongly suggest crucial roles of the HOXC13 gene in the development of hair and nails in humans. © 2013 Wiley Periodicals, Inc.

  14. Identification of a homozygous PSTPIP1 mutation in a patient with a PAPA-like syndrome responding to canakinumab treatment.

    Science.gov (United States)

    Geusau, Alexandra; Mothes-Luksch, Nadine; Nahavandi, Hesam; Pickl, Winfried F; Wise, Carol A; Pourpak, Zahra; Ponweiser, Elisabeth; Eckhart, Leopold; Sunder-Plassmann, Raute

    2013-02-01

    Pyogenic sterile arthritis, pyoderma gangrenosum, and acne (PAPA) syndrome (OMIM 604416) is a rare autosomal dominant inherited autoinflammatory syndrome characterized by pyogenic sterile arthritis and less frequently accompanied by pyoderma gangrenosum and acne. It is associated with dominant missense mutations in the proline-serine-threonine phosphatase-interacting protein 1 gene (PSTPIP1) located on chromosome 15. The patient was diagnosed as having features of a PAPA-like syndrome in which cutaneous manifestations, such as pyoderma gangrenosum and acne fulminans, predominated. Sequencing of the PSTPIP1 gene was performed in the patient and his extended family. The patient's DNA analysis revealed a homozygous nucleotide exchange c.773G>C in the PSTPIP1 gene, leading to the substitution of glycine 258 by alanine (p.Gly258Ala), a previously reported heterozygous polymorphism. Heterozygous changes were identified in both of the patient's parents and in 7 other family members, all of whom were asymptomatic. The patient was treated with canakinumab, a human anti-interleukin 1β monoclonal antibody, which led to rapid remission of the symptoms. To our knowledge, this is the first reported case of the resolution of dermatological symptoms associated with a PAPA-like syndrome using canakinumab treatment. Further study of the p.Gly258Ala variant is warranted to determine whether this mutation has a role in causing an apparently recessive cutaneous syndrome resembling PAPA syndrome.

  15. Liver transplantation in a subject with familial hypercholesterolemia carrying the homozygous p.W577R LDL-receptor gene mutation

    NARCIS (Netherlands)

    Schmidt, Hartmut H-J.; Tietge, Uwe J. F.; Buettner, Janine; Barg-Hock, Hannelore; Offner, Gisela; Schweitzer, Susanne; Dedoussis, Giorgos V.; Rodeck, Burkhard; Kallfelz, Hans C.; Schlitt, Hans-Juergen; Oldhafer, Karl; Klempnauer, Juergen

    2008-01-01

    Mutations within the low density lipoprotein (LDL)-receptor gene result in familial hypercholesterolemia, an autosomal dominant inherited disease. Clinical homozygous affected subjects die of premature coronary artery disease as early as in early childhood. We identified a girl at the age of five yr

  16. Sensory ataxic neuropathy dysarthria and ophthalmoparesis (SANDO) in a sibling pair with a homozygous p.A467T POLG mutation.

    LENUS (Irish Health Repository)

    McHugh, John C

    2012-02-01

    Two siblings who developed fifth-decade-onset, concurrent progressive sensory ataxia, dysarthria, and ophthalmoparesis were found to be homozygous for the p.A467T mutation of the polymerase gamma (POLG) gene. The clinical course in both subjects was progression to severe disability. The enlarging spectrum of sensory ataxic neuropathies associated with mitochondrial DNA (mtDNA) instability and POLG mutations should be recognized and considered in the differential diagnosis of this unusual presentation.

  17. Mutations in HAMP and HJV genes and their impact on expression of clinical hemochromatosis in a cohort of 100 Spanish patients homozygous for the C282Y mutation of HFE gene.

    Science.gov (United States)

    Altès, Albert; Bach, Vanessa; Ruiz, Angels; Esteve, Anna; Felez, Jordi; Remacha, Angel F; Sardà, M Pilar; Baiget, Montserrat

    2009-10-01

    Most hereditary hemochromatosis (HH) patients are homozygous for the C282Y mutation of the HFE gene. Nevertheless, penetrance of the disease is very variable. In some patients, penetrance can be mediated by concomitant mutations in other iron master genes. We evaluated the clinical impact of hepcidin (HAMP) and hemojuvelin mutations in a cohort of 100 Spanish patients homozygous for the C282Y mutation of the HFE gene. HAMP and hemojuvelin mutations were evaluated in all patients by bidirectional direct cycle sequencing. Phenotype-genotype interactions were evaluated. A heterozygous mutation of the HAMP gene (G71D) was found in only one out of 100 cases. Following, we performed a study of several members of that family, and we observed several members had a digenic inheritance of the C282Y mutation of the HFE gene and the G71D mutation of the HAMP gene. This mutation in the HAMP gene did not modify the phenotype of the individuals who were homozygous for the C282Y mutation. One other patient presented a new polymorphism in the hemojuvelin gene, without consequences in iron load or clinical course of the disease. In conclusion, HAMP and hemojuvelin mutations are rare among Spanish HH patients, and their impact in this population is not significant.

  18. Odonto-onycho-dermal dysplasia in a patient homozygous for a WNT10A nonsens mutation and mild manifestations of ectodermal dysplasia in carriers of the mutation

    DEFF Research Database (Denmark)

    Bruun Krøigård, Anne; Clemmensen, Ole; Gjørup, Hans

    2016-01-01

    history of tooth anomalies, this lead to the clinical suspicion of a hereditary ectodermal dysplasia. CONCLUSION: This case illustrates the challenges of diagnosing ectodermal dysplasia like OODD and highlights the relevance of interdisciplinary cooperation in the diagnosis of rare conditions....... in the WNT10A gene result in highly variable phenotypes, ranging from isolated tooth agenesis to OODD and Schöpf-Schulz-Passarge syndrome (SSPS). CASE PRESENTATION: We identified a female patient, with consanguineous parents, who was clinically diagnosed with OODD. Genetic testing showed that she...... was homozygous for a previously reported pathogenic mutation in the WNT10A gene, c.321C > A, p.Cys107*. The skin and nail abnormalities were for many years interpreted as psoriasis and treated accordingly. A thorough clinical examination revealed hypotrichosis and hyperhidrosis of the soles and dental...

  19. Expanding the clinical spectrum of B4GALT7 deficiency: homozygous p.R270C mutation with founder effect causes Larsen of Reunion Island syndrome

    Science.gov (United States)

    Cartault, François; Munier, Patrick; Jacquemont, Marie-Line; Vellayoudom, Jeannine; Doray, Bérénice; Payet, Christine; Randrianaivo, Hanitra; Laville, Jean-Marc; Munnich, Arnold; Cormier-Daire, Valérie

    2015-01-01

    First described as a variant of Larsen syndrome in Reunion Island (LRS) in the southern Indian Ocean, ‘Larsen of Reunion Island syndrome' is characterized by dwarfism, hyperlaxity, multiple dislocations and distinctive facial features. It overlaps with Desbuquois dysplasia, Larsen syndrome and spondyloepiphyseal dysplasia with dislocations ascribed to CANT1, FLNB and CHST3 mutations, respectively. We collected the samples of 22 LRS cases. After exclusion of CANT1, FLNB and CHST3 genes, an exome sequencing was performed in two affected second cousins and one unaffected sister. We identified a homozygous missense mutation in B4GALT7, NM_007255.2: c.808C>T p.(Arg270Cys) named p.R270C, in the two affected cases, not present in the unaffected sister. The same homozygous mutation was subsequently identified in the remaining 20 LRS cases. Our findings demonstrate that B4GALT7 is the causative gene for LRS. The identification of a unique homozygous mutation argues in favor of a founder effect. B4GALT7 encodes a galactosyltransferase, required for the initiation of glycoaminoglycan side chain synthesis of proteoglycans. This study expands the phenotypic spectrum of B4GALT7 mutations, initially described as responsible for the progeroid variant of Ehlers–Danlos syndrome. It further supports a common physiopathological basis involving proteoglycan synthesis in skeletal disorders with dislocations. PMID:24755949

  20. Homozygous c.649dupC mutation in PRRT2 worsens the BFIS/PKD phenotype with mental retardation, episodic ataxia, and absences.

    Science.gov (United States)

    Labate, Angelo; Tarantino, Patrizia; Viri, Maurizio; Mumoli, Laura; Gagliardi, Monica; Romeo, Antonino; Zara, Federico; Annesi, Grazia; Gambardella, Antonio

    2012-12-01

    Heterozygous mutations of PRRT2, which encodes proline-rich transmembrane protein 2, are associated with heterogeneous phenotypes including benign familial infantile seizures (BFIS), or familial paroxysmal kinesigenic dystonia (PKD). We report a consanguineous Italian family with BFIS/PKD phenotype that contained 14 living members with 6 affected individuals (four men, ranging in age from 6-44 years). We identified the reported c.649dupC (p.Arg217ProfsX8) mutation of PRRT2 gene that cosegregated with the disease and was not observed in 100 controls of matched ancestry. Four patients with BFIS phenotype were heterozygous for this mutation, including the consanguineous parents of the two affected brothers with more severe phenotypes of BFIS/PKD--mental retardation, episodic ataxia, and absences--who were the only individuals to carry a homozygous c.649dupC mutation. This family provides strong evidence that homozygous PRRT2 mutations give rise to more severe clinical disease of mental retardation, episodic ataxia, and absences, and, thus, enlarges the clinical spectrum related to PRRT2 mutations. Moreover, it suggests an additive effect of double dose of the genetic mutation and underscores the complexity of the phenotypic consequences of mutations in this gene. Wiley Periodicals, Inc. © 2012 International League Against Epilepsy.

  1. Novel Homozygous Missense Mutation in SPG20 Gene Results in Troyer Syndrome Associated with Mitochondrial Cytochrome c Oxidase Deficiency.

    Science.gov (United States)

    Spiegel, Ronen; Soiferman, Devorah; Shaag, Avraham; Shalev, Stavit; Elpeleg, Orly; Saada, Ann

    2017-01-01

    Troyer syndrome is an autosomal recessive form of hereditary spastic paraplegia (HSP) caused by deleterious mutations in the SPG20 gene. Although the disease is associated with a loss of function mechanism of spartin, the protein encoded by SPG20, the precise pathogenesis is yet to be elucidated. Recent data indicated an important role for spartin in both mitochondrial maintenance and function. Here we report a child presenting with progressive spastic paraparesis, generalized muscle weakness, dysarthria, impaired growth, and severe isolated decrease in muscle cytochrome c oxidase (COX) activity. Whole exome sequencing identified the homozygous c.988A>G variant in SPG20 gene (p.Met330Val) resulting in almost complete loss of spartin in skeletal muscle. Further analyses demonstrated significant tissue specific reduction of COX 4, a nuclear encoded subunit of COX, in muscle suggesting a role for spartin in proper mitochondrial respiratory chain function mediated by COX activity. Our findings need to be verified in other Troyer syndrome patients in order to classify it as a form of HSP caused by mitochondrial dysfunction.

  2. Activation-resistant homozygous protein C R229W mutation causing familial perinatal intracranial hemorrhage and delayed onset of thrombosis.

    Science.gov (United States)

    Alsultan, Abdulrahman; Gale, Andrew J; Kurban, Kadijah; Khalifah, Mohammed; Albadr, Fahad B; Griffin, John H

    2016-07-01

    We describe a family with two first-degree cousins who presented with similar phenotypes characterized by neonatal intracranial hemorrhage and subsequent onset of thrombosis. We enrolled the two affected patients, five unaffected family members and fifty-five normal controls. Clinical, laboratory, and radiological characteristics of patients were obtained. Exome sequencing was performed for the older affected child. PROC c.811 C>T was genotyped by PCR in patients, family members, and controls. Protein C amidolytic activity and antigen were measured using the STACHROM® protein C kit and ELISAs. To define functional abnormalities caused by the patients' mutation, recombinant wildtype protein C and its mutants R229W, R229Q and R229A were studied. For the two cousins, protein C amidolytic activity was 61% and 59% and antigen was 57% and 73% (nl 70-140%), respectively. Exome sequencing revealed a homozygous variant in exon 9 of the protein C (PROC) gene c.811 C>T (R229W). The R229W mutation is located in the calcium binding loop of protein C's protease domain that mediates thrombomodulin interactions. Recombinant R229W-protein C mutant was strikingly defective in rate of activation by thrombin: thrombomodulin, suggesting an in vivo deficit in these children for generation of activated protein C. These cases emphasize that protein C and activated protein C are important in maintaining the integrity of the brain vascular endothelium in humans. Moreover, routine protein C assays utilizing snake venom protease fail to detect protein C mutants that are resistant to thrombin:thrombomodulin activation. Copyright © 2016 Elsevier Ltd. All rights reserved.

  3. An RNA Aptamer Inhibits a Mutation-Induced Inactivating Misfolding of a Serpin

    DEFF Research Database (Denmark)

    Madsen, Jeppe B; Andersen, Lisbeth M; Dupont, Daniel M

    2016-01-01

    ) or extracellularly (type-II serpinopathies). We have isolated a 2'-fluoropyrimidine-modified RNA aptamer, which inhibits a mutation-induced inactivating misfolding of the serpin α1-antichymotrypsin. It is the first agent able to stabilize a type-II mutation of a serpin without interfering with the inhibitory...

  4. Molecular analyses of novel ASAH1 mutations causing Farber lipogranulomatosis: analyses of exonic splicing enhancer inactivating mutation.

    Science.gov (United States)

    Bashyam, M D; Chaudhary, A K; Kiran, M; Reddy, V; Nagarajaram, H A; Dalal, A; Bashyam, L; Suri, D; Gupta, A; Gupta, N; Kabra, M; Puri, R D; RamaDevi, R; Kapoor, S; Danda, S

    2014-12-01

    Farber lipogranulomatosis is a rare autosomal recessive lysosomal storage disorder caused by mutations in the ASAH1 gene. In the largest ever study, we identified and characterized ASAH1 mutations from 11 independent Farber disease (FD) families. A total of 13 different mutations were identified including 1 splice, 1 polypyrimidine tract (PPT) deletion and 11 missense mutations. Eleven mutations were exclusive to the Indian population. The IVS6+4A>G splice and IVS5-16delTTTTC PPT deletion mutations resulted in skipping of exon 6 precluding thereby the region responsible for cleavage of enzyme precursor. A missense mutation (p.V198A) resulted in skipping of exon 8 due to inactivation of an exonic splicing enhancer (ESE) element. This is the first report of mutations affecting PPT and ESE in the ASAH1 gene resulting in FD. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. A case report of pedigree of a homozygous mutation of the steroidogenic acute regulatory protein causing lipoid congenital adrenal hyperplasia

    Science.gov (United States)

    Fu, Rong; Lu, Lin; Jiang, Jun; Nie, Min; Wang, Xiaojing; Lu, Zhaolin

    2017-01-01

    Abstract Rationale: Lipoid congenital adrenal hyperplasia (LCAH) is extremely rare, but is the most fatal form of congenital adrenal hyperplasia resulting from mutations in the steroidogenic acute regulatory protein (STAR) gene. LCAH arises from severe defects in the conversion of cholesterol to pregnenolone, the precursor of all steroids. Patient concerns: A case was reported that an 11-month-old Chinese girl who presented with a sex development disorder and hyponatremia. The clinical and genetic tests were carried out to confirm the diagnosis. The genogram of this case was also explored and analyzed. The girl presented with hyponatremia, decreased cortisol level, elevated adrenocorticotropic hormone level and female vulva despite a 46, XY karyotype. Enlarged adrenal glands and testicular-like tissue in the bilateral inguinal regions were detected with abdominal ultrasound. She was suspected of having LCAH, and definitive diagnosis was made after Sanger sequencing detected a homozygous frameshift variant c.707_708delins CTT (p.Lys236Thrfs∗47) on exon 6 of the STAR gene. Diagnoses: LCAH. Interventions: She was prescribed hydrocortisone 10 to 12 mg/m2 and 9a- fludrocortisone 100 mg/d. Outcomes: Her skin hyperpigmentation and vomiting disappeared, and she had normal growth and development without adrenal crisis attacks. Her hormone and electrolyte levels remained normal, except for a persistently elevated ACTH level throughout 2 years of follow-up. At follow-up for 2 years, the patient is now 104.5 cm tall and weighs 23.3 kg at the age of 4 years old. Her plasma sodium and potassium concentration were normal. Her ACTH level is still elevated (1176 pg/mL). Her baseline sex hormone levels are testosterone adrenal insufficiency and female phenotype initially. The diagnosis was complicated depending on the clinical hormone workup. LCAH was confirmed by genetic tests and genogram of the family. PMID:28538409

  6. A New Mouse Model of Limb-Girdle Muscular Dystrophy Type 2I Homozygous for the Common L276I Mutation Mimicking the Mild Phenotype in Humans

    DEFF Research Database (Denmark)

    Krag, Thomas O; Vissing, John

    2015-01-01

    Limb-girdle muscular dystrophy type 2I (LGMD2I) is caused by mutations in the Fukutin-related protein (FKRP) gene, leading to inadequate glycosylation of α-dystroglycan, an important protein linking the extracellular matrix to the cytoskeleton. We created a mouse model of the common FKRP L276I...... mutation and a hemizygous FKRP L276I knockout model. We studied histopathology and protein expression in the models at different ages and found that homozygous FKRP L276I mice developed a mild progressive myopathy with increased muscle regeneration and fibrosis starting from 1 year of age. This was likely...

  7. A novel homozygous mutation causing lecithin-cholesterol acyltransferase deficiency in a proband of Romanian origin with a record of extreme gestational hyperlipidemia.

    Science.gov (United States)

    Rial-Crestelo, David; Santos-Recuero, Ildefonso; Julve, Josep; Blanco-Vaca, Francisco; Torralba, Miguel

    A patient from Romania with extraordinarily high total cholesterol levels and clinical and biochemical features consistent with familial lecithin-cholesterol acyltransferase deficiency is reported. The genetic analysis performed on our proband showed a novel homozygous mutation on codon 119 of lecithin-cholesterol acyltransferase gene that causes the substitution of glycine by aspartate. The same mutation, also in homozygosis, was observed in her older sister, whereas his brother presented it in heterozygosis. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  8. A mutation in segment I-S6 alters slow inactivation of sodium channels.

    Science.gov (United States)

    Wang, S Y; Wang, G K

    1997-01-01

    Slow inactivation occurs in voltage-gated Na+ channels when the membrane is depolarized for several seconds, whereas fast inactivation takes place rapidly within a few milliseconds. Unlike fast inactivation, the molecular entity that governs the slow inactivation of Na+ channels has not been as well defined. Some regions of Na+ channels, such as mu1-W402C and mu1-T698M, have been reported to affect slow inactivation. A mutation in segment I-S6 of mu1 Na+ channels, N434A, shifts the voltage dependence of activation and fast inactivation toward the depolarizing direction. The mutant Na+ current at +50 mV is diminished by 60-80% during repetitive stimulation at 5 Hz, resulting in a profound use-dependent phenomenon. This mutant phenotype is due to the enhancement of slow inactivation, which develops faster than that of wild-type channels (tau = 0.46 +/- 0.01 s versus 2.11 +/- 0.10 s at +30 mV, n = 9). An oxidant, chloramine-T, abolishes fast inactivation and yet greatly accelerates slow inactivation in both mutant and wild-type channels (tau = 0.21 +/- 0.02 s and 0.67 +/- 0.05 s, respectively, n = 6). These findings together demonstrate that N434 of mu1 Na+ channels is also critical for slow inactivation. We propose that this slow form of Na+ channel inactivation is analogous to the "C-type" inactivation in Shaker K+ channels. PMID:9083667

  9. Neuroendocrine phenotype analysis in five patients with isolated hypogonadotropic hypogonadism due to a L102P inactivating mutation of GPR54.

    Science.gov (United States)

    Tenenbaum-Rakover, Yardena; Commenges-Ducos, Monique; Iovane, André; Aumas, Chantal; Admoni, Osnat; de Roux, Nicolas

    2007-03-01

    Loss of function of the G protein-coupled receptor of kisspeptins (GPR54) was recently described as a new cause of isolated hypogonadotropic hypogonadism. In vivo studies performed in several species have confirmed the major role of kisspeptins in neuroendocrine regulation of the gonadotropic axis and therefore sexual maturation. The objective of this study was to specify the exact contribution of kisspeptins and GPR54 to the initiation of puberty in humans. Detailed neuroendocrine descriptions were performed in five patients with isolated hypogonadotropic hypogonadism bearing a new GPR54-inactivating mutation. A homozygous mutation (T305C) leading to a leucine substitution with proline (L102P) was found in the five affected patients. This substitution completely inhibited GPR54 signaling. Phenotypic analysis revealed variable expressivity in the same family, either partial or complete gonadotropic deficiency. LH pulsatility analysis showed peaks with normal frequency but low amplitude. Repeated GnRH tests performed between 12 and 21 yr of age in one affected male revealed progressive changes in pituitary response from an early pubertal to an almost full pubertal pattern. Double GnRH test stimulations performed at a 120-min interval showed reduced dynamic pituitary response in GPR54-mutated patients. GPR54 inactivation does not impede neuroendocrine onset of puberty; rather, it delays and slows down pubertal maturation of the gonadotropic axis. The L102P loss of function mutation in GPR54 results in a more quantitative than qualitative defect of gonadotropic axis activation.

  10. A systematic study of gene mutations in urothelial carcinoma; inactivating mutations in TSC2 and PIK3R1.

    Directory of Open Access Journals (Sweden)

    Gottfrid Sjödahl

    Full Text Available BACKGROUND: Urothelial carcinoma (UC is characterized by frequent gene mutations of which activating mutations in FGFR3 are the most frequent. Several downstream targets of FGFR3 are also mutated in UC, e.g., PIK3CA, AKT1, and RAS. Most mutation studies of UCs have been focused on single or a few genes at the time or been performed on small sample series. This has limited the possibility to investigate co-occurrence of mutations. METHODOLOGY/PRINCIPAL FINDINGS: We performed mutation analyses of 16 genes, FGFR3, PIK3CA, PIK3R1 PTEN, AKT1, KRAS, HRAS, NRAS, BRAF, ARAF, RAF1, TSC1, TSC2, APC, CTNNB1, and TP53, in 145 cases of UC. We show that FGFR3 and PIK3CA mutations are positively associated. In addition, we identified PIK3R1 as a target for mutations. We demonstrate a negative association at borderline significance between FGFR3 and RAS mutations, and show that these mutations are not strictly mutually exclusive. We show that mutations in BRAF, ARAF, RAF1 rarely occurs in UC. Our data emphasize the possible importance of APC signaling as 6% of the investigated tumors either showed inactivating APC or activating CTNNB1 mutations. TSC1, as well as TSC2, that constitute the mTOR regulatory tuberous sclerosis complex were found to be mutated at a combined frequency of 15%. CONCLUSIONS/SIGNIFICANCE: Our data demonstrate a significant association between FGFR3 and PIK3CA mutations in UC. Moreover, the identification of mutations in PIK3R1 further emphasizes the importance of the PI3-kinase pathway in UC. The presence of TSC2 mutations, in addition to TSC1 mutations, underlines the involvement of mTOR signaling in UC.

  11. Hypophosphatemic osteomalacia and bone sclerosis caused by a novel homozygous mutation of the FAM20C gene in an elderly man with a mild variant of Raine syndrome.

    Science.gov (United States)

    Takeyari, Shinji; Yamamoto, Takehisa; Kinoshita, Yuka; Fukumoto, Seiji; Glorieux, Francis H; Michigami, Toshimi; Hasegawa, Kosei; Kitaoka, Taichi; Kubota, Takuo; Imanishi, Yasuo; Shimotsuji, Tsunesuke; Ozono, Keiichi

    2014-10-01

    Hypophosphatemia and increased serum fibroblast growth factor 23 (FGF23) levels have been reported in young brothers with compound heterozygous mutations for the FAM20C gene; however, rickets was not observed in these cases. We report an adult case of Raine syndrome accompanying hypophosphatemic osteomalacia with a homozygous FAM20C mutation (R408W) associated with increased periosteal bone formation in the long bones and an increase in bone mineral density in the femoral neck. The patient, a 61-year-old man, was born from a cousin-to-cousin marriage. A short stature and severe dental demineralization were reported at an elementary school age. Hypophosphatemia was noted inadvertently at 27years old, at which time he started to take an active vitamin D metabolite (alphacalcidol) and phosphate. He also manifested ossification of the posterior longitudinal ligament. On bone biopsy performed at the age of 41years, we found severe osteomalacia surrounding osteocytes, which appeared to be an advanced form of periosteocytic hypomineralized lesions compared to those reported in patients with X-linked hypophosphatemic rickets. Laboratory data at 61years of age revealed markedly increased serum intact-FGF23 levels, which were likely to be the cause of hypophosphatemia and the decreased level of 1,25(OH)2D. We recently identified a homozygous FAM20C mutation, which was R408W, in this patient. When expressed in HEK293 cells, the R408W mutant protein exhibited impaired kinase activity and secretion. Our findings suggest that certain homozygous FAM20C mutations can cause FGF23-related hypophosphatemic osteomalacia and indicate the multiple roles of FAM20C in bone. Copyright © 2014 Elsevier Inc. All rights reserved.

  12. Effects of track structure and cell inactivation on the calculation of heavy ion mutation rates in mammalian cells

    Science.gov (United States)

    Cucinotta, F. A.; Wilson, J. W.; Shavers, M. R.; Katz, R.

    1996-01-01

    It has long been suggested that inactivation severely effects the probability of mutation by heavy ions in mammalian cells. Heavy ions have observed cross sections of inactivation that approach and sometimes exceed the geometric size of the cell nucleus in mammalian cells. In the track structure model of Katz the inactivation cross section is found by summing an inactivation probability over all impact parameters from the ion to the sensitive sites within the cell nucleus. The inactivation probability is evaluated using the dose-response of the system to gamma-rays and the radial dose of the ions and may be equal to unity at small impact parameters for some ions. We show how the effects of inactivation may be taken into account in the evaluation of the mutation cross sections from heavy ions in the track structure model through correlation of sites for gene mutation and cell inactivation. The model is fit to available data for HPRT mutations in Chinese hamster cells and good agreement is found. The resulting calculations qualitatively show that mutation cross sections for heavy ions display minima at velocities where inactivation cross sections display maxima. Also, calculations show the high probability of mutation by relativistic heavy ions due to the radial extension of ions track from delta-rays in agreement with the microlesion concept. The effects of inactivation on mutations rates make it very unlikely that a single parameter such as LET or Z*2/beta(2) can be used to specify radiation quality for heavy ion bombardment.

  13. The homozygous VHL(D126N) missense mutation is associated with dramatically elevated erythropoietin levels, consequent polycythemia, and early onset severe pulmonary hypertension.

    Science.gov (United States)

    Sarangi, Susmita; Lanikova, Lucie; Kapralova, Katarina; Acharya, Suchitra; Swierczek, Sabina; Lipton, Jeffrey M; Wolfe, Lawrence; Prchal, Josef T

    2014-11-01

    von Hippel-Lindau (VHL) protein is the principal negative regulator of hypoxia sensing mediated by transcription factors. Mutations in exon 3 of the VHL gene lead to Chuvash (VHL(R200W)) and Croatian (VHL(H191D)) polycythemias. Here, we describe an infant of Bangladesh ethnicity with a novel homozygous VHL(D126N) mutation with congenital polycythemia and dramatically elevated erythropoietin (EPO) levels, who developed severe fatal pulmonary hypertension. In contrast to Chuvash polycythemia, erythroid progenitors (BFU-Es) did not reveal a marked EPO hypersensitivity. Further, NF-E2 and RUNX1 transcripts that correlate with BFU-Es EPO hypersensitivity in polycythemic mutations were not elevated. © 2014 Wiley Periodicals, Inc.

  14. Adult siblings with homozygous G6PC3 mutations expand our understanding of the severe congenital neutropenia type 4 (SCN4 phenotype

    Directory of Open Access Journals (Sweden)

    Fernandez Bridget A

    2012-11-01

    Full Text Available Abstract Background Severe congenital neutropenia type 4 (SCN4 is an autosomal recessive disorder caused by mutations in the third subunit of the enzyme glucose-6-phosphatase (G6PC3. Its core features are congenital neutropenia and a prominent venous skin pattern, and affected individuals have variable birth defects. Oculocutaneous albinism type 4 (OCA4 is caused by autosomal recessive mutations in SLC45A2. Methods We report a sister and brother from Newfoundland, Canada with complex phenotypes. The sister was previously reported by Cullinane et al., 2011. We performed homozygosity mapping, next generation sequencing and conventional Sanger sequencing to identify mutations that cause the phenotype in this family. We have also summarized clinical data from 49 previously reported SCN4 cases with overlapping phenotypes and interpret the medical histories of these siblings in the context of the literature. Results The siblings’ phenotype is due in part to a homozygous mutation in G6PC3, [c.829C > T, p.Gln277X]. Their ages are 38 and 37 years respectively and they are the oldest SCN4 patients published to date. Both presented with congenital neutropenia and later developed Crohn disease. We suggest that the latter is a previously unrecognized SCN4 manifestation and that not all affected individuals have an intellectual disability. The sister also has a homozygous mutation in SLC45A2, which explains her severe oculocutaneous hypopigmentation. Her brother carried one SLC45A2 mutation and was diagnosed with “partial OCA” in childhood. Conclusions This family highlights that apparently novel syndromes can in fact be caused by two known autosomal recessive disorders.

  15. Hypogonadotropic hypogonadism in a homozygous MC4R mutation carrier and the effect of sibutramine treatment on body weight and obesity-related health risks.

    Science.gov (United States)

    Hainerová, Irena Aldhoon; Zamrazilová, Hana; Sedláčková, Dana; Hainer, Vojtěch

    2011-01-01

    The first aim of our study was to define the hypogonadism manifested by low testosterone levels and incomplete male secondary sex characteristics in a 20-year-old male homozygous MC4R mutation carrier (G181D). The second aim of our study was to evaluate the effect of the anti-obesity drug sibutramine in this patient who failed to respond to an intensive lifestyle intervention and exhibited continuous weight gain. Anthropometric, biochemical, hormonal and psycho-behavioural parameters were investigated both at baseline and after a 1-year sibutramine treatment. To characterise the hypogonadism, sex steroid profile, concentrations of luteinizing hormone and follicle-stimulating hormone were determined. Standard tests with gonadotropin-releasing hormone, thyrotropin-releasing hormone and human chorionic gonadotropin were conducted. Brain magnetic resonance imaging was performed to exclude organic hypothalamic-pituitary lesions. Clinical examination and endocrine investigations revealed hypogonadotropic hypogonadism. Sibutramine induced body weight maintenance as well as improvement in body composition and obesity-related metabolic abnormalities. We described the first case of hypogonadotropic hypogonadism in a MC4R homozygous mutation carrier. The potential association between the hormonal disturbance and the hypothalamic derangement caused by the MC4R mutation should be considered. In addition, we demonstrated that sibutramine treatment had a favourable effect on body weight maintenance and obesity-related health risks. Copyright © 2011 S. Karger AG, Basel.

  16. Inactivating mutations in NPC1L1 and protection from coronary heart disease

    NARCIS (Netherlands)

    Stitziel, Nathan O.; Won, Hong-Hee; Morrison, Alanna C.; Peloso, Gina M.; Do, Ron; Lange, Leslie A.; Fontanillas, Pierre; Gupta, Namrata; Duga, Stefano; Goel, Anuj; Farrall, Martin; Saleheen, Danish; Ferrario, Paola; König, Inke; Asselta, Rosanna; Merlini, Piera A.; Marziliano, Nicola; Notarangelo, Maria Francesca; Schick, Ursula; Auer, Paul; Assimes, Themistocles L.; Reilly, Muredach; Wilensky, Robert; Rader, Daniel J.; Hovingh, G. Kees; Meitinger, Thomas; Kessler, Thorsten; Kastrati, Adnan; Laugwitz, Karl-Ludwig; Siscovick, David; Rotter, Jerome I.; Hazen, Stanley L.; Tracy, Russell; Cresci, Sharon; Spertus, John; Jackson, Rebecca; Schwartz, Stephen M.; Natarajan, Pradeep; Crosby, Jacy; Muzny, Donna; Ballantyne, Christie; Rich, Stephen S.; O'Donnell, Christopher J.; Abecasis, Goncalo; Sunyaev, Shamil; Nickerson, Deborah A.; Buring, Julie E.; Ridker, Paul M.; Chasman, Daniel I.; Austin, Erin; Ye, Zi; Kullo, Iftikhar J.; Weeke, Peter E.; Shaffer, Christian M.; Bastarache, Lisa A.; Denny, Joshua C.; Roden, Dan M.; Palmer, Colin; Deloukas, Panos; Lin, Dan-Yu; Tang, Zheng-zheng; Erdmann, Jeanette; Schunkert, Heribert; Danesh, John; Marrugat, Jaume; Elosua, Roberto; Ardissino, Diego; McPherson, Ruth; Watkins, Hugh; Reiner, Alex P.; Wilson, James G.; Altshuler, David; Gibbs, Richard A.; Lander, Eric S.; Boerwinkle, Eric; Gabriel, Stacey; Kathiresan, Sekar

    2014-01-01

    Ezetimibe lowers plasma levels of low-density lipoprotein (LDL) cholesterol by inhibiting the activity of the Niemann-Pick C1-like 1 (NPC1L1) protein. However, whether such inhibition reduces the risk of coronary heart disease is not known. Human mutations that inactivate a gene encoding a drug

  17. A homozygous nonsense mutation in the {alpha}3 chain gene of laminin 5 (LAMA3) in Herlitz junctional epidermolysis bullosa: Prenatal exclusion in a fetus at risk

    Energy Technology Data Exchange (ETDEWEB)

    McGrath, J.A. [Jefferson Medical College, Philadelphia, PA (United States)]|[St. Thomas Hospital, London (United Kingdom); Ciatti, S.; Christiano, A.M. [Jefferson Medical College, Philadelphia, PA (United States)] [and others

    1995-09-01

    Mutations in the three genes (LAMA3, LAMB3, and LAMC2) that encode the three chains ({alpha}3, {Beta}3, and {gamma}2, respectively) of laminin 5, a protein involved in epidermal-dermal adhesion, have been established as the genetic basis for the inherited blistering skin disorder, Herlitz junctional epidermolysis bullosa (H-JEB). In this study, we performed mutational analysis on genomic DNA from a child with H-JEB and identified a nonsense mutation in the {alpha}3 chain gene (LAMA3) consisting of a homozygous C-to-T transition resulting in a premature termination codon (CGA {r_arrow} TGA) on both alleles. The parents were shown to be heterozygous carriers of the same mutation. Direct mutation analysis was used to perform DNA-based prenatal diagnosis from a chorionic villus biopsy at 10 weeks` gestation in a subsequent pregnancy. The fetus was predicted to be genotypically normal with respect to the LAMA3 mutation. 15 refs., 1 fig.

  18. Seemingly neutral polymorphic variants may confer immunity to splicing-inactivating mutations

    DEFF Research Database (Denmark)

    Nielsen, Karsten Bork; Sørensen, Suzette; Cartegni, Luca

    2007-01-01

    The idea that point mutations in exons may affect splicing is intriguing and adds an additional layer of complexity when evaluating their possible effects. Even in the best-studied examples, the molecular mechanisms are not fully understood. Here, we use patient cells, model minigenes, and in vitro...... assays to show that a missense mutation in exon 5 of the medium-chain acyl-CoA dehydrogenase (MCAD) gene primarily causes exon skipping by inactivating a crucial exonic splicing enhancer (ESE), thus leading to loss of a functional protein and to MCAD deficiency. This ESE functions by antagonizing...... a juxtaposed exonic splicing silencer (ESS) and is necessary to define a suboptimal 3' splice site. Remarkably, a synonymous polymorphic variation in MCAD exon 5 inactivates the ESS, and, although this has no effect on splicing by itself, it makes splicing immune to deleterious mutations in the ESE...

  19. Severe early onset retinitis pigmentosa in a Moroccan patient with Heimler syndrome due to novel homozygous mutation of PEX1 gene.

    Science.gov (United States)

    Ratbi, Ilham; Jaouad, Imane Cherkaoui; Elorch, Hamza; Al-Sheqaih, Nada; Elalloussi, Mustapha; Lyahyai, Jaber; Berraho, Amina; Newman, William G; Sefiani, Abdelaziz

    2016-10-01

    Heimler syndrome (HS) is a rare recessive disorder characterized by sensorineural hearing loss (SNHL), amelogenesis imperfecta, nail abnormalities, and occasional or late-onset retinal pigmentation. It is the mildest form known to date of peroxisome biogenesis disorder caused by hypomorphic mutations of PEX1 and PEX6 genes. We report on a second Moroccan family with Heimler syndrome with early onset, severe visual impairment and important phenotypic overlap with Usher syndrome. The patient carried a novel homozygous missense variant c.3140T > C (p.Leu1047Pro) of PEX1 gene. As standard biochemical screening of blood for evidence of a peroxisomal disorder did not provide a diagnosis in the individuals with HS, patients with SNHL and retinal pigmentation should have mutation analysis of PEX1 and PEX6 genes. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  20. A case of early-onset obesity, hypocortisolism, and skin pigmentation problem due to a novel homozygous mutation in the proopiomelanocortin (POMC) gene in an Indian boy.

    Science.gov (United States)

    Hung, Ching-Ngar; Poon, Wing-Tat; Lee, Ching-Yin; Law, Chun-Yiu; Chan, Albert Yan-Wo

    2012-01-01

    Proopiomelanocortin (POMC) is the polypeptide precursor of several biologically active melanocortin peptides that have important roles in the regulation of food intake and energy homeostasis, adrenal steroidogenesis, melanocyte stimulation, and immune modulation. Mutation of the POMC gene has been associated with adrenal insufficiency, early-onset obesity, and red hair pigmentation. We describe an Indian boy with secondary hypocortisolism, hyperphagia, early-onset obesity, and skin pigmentation problem. Genetics analysis revealed a novel homozygous mutation in the POMC gene (p.Arg86Term). The boy also had central hypothyroidism in addition to the secondary hypocortisolism. Genetics analysis for the POMC gene should be considered in patients with secondary hypocortisolism, early-onset obesity, and pigmentary problems.

  1. Lumacaftor/ivacaftor, a novel agent for the treatment of cystic fibrosis patients who are homozygous for the F580del CFTR mutation.

    Science.gov (United States)

    Bulloch, Marilyn N; Hanna, Cameron; Giovane, Richard

    2017-10-01

    Cystic Fibrosis (CF) is an autosomal recessive disease affecting up to 90,000 people worldwide. Approximately 73% of patients are homozygous for the F508del cystic fibrosis transmembrane conductance regulator [CFTR] mutation. Traditionally treatment has only included supportive care. Therefore, there is a need for safe and effective novel therapies targeting the underlying molecular defects seen with CF. Areas covered: In 2016, the Food and Drug Administration and the European Commission approved LUM/IVA (Orkambi), a CFTR modulator that includes both a CFTR corrector and potentiator, for CF patients homozygous for the F508del CFTR mutation. This article reviews the pharmacologic features, clinical efficacy, and safety of LUM/IVA and summarize the available pre-clinical and clinical data of LUM/IVA use. Expert commentary: LUM/IVA showed modest, but significant improvements from baseline in percent predicted FEV1 (ppFEV1) as well as a reduction in pulmonary exacerbations by 35% It was shown to be safe for short- and long-term use. Currently, LUM/IVA is the only oral agent in its class available and represents a milestone the development of therapies for the management of CF. Nonetheless, pharmacoeconomic data are necessary to justify its high cost before is use becomes standard of care.

  2. CO-OCCURRENCE OF PRIMARY MICROCEPHALY CAUSED BY A NOVEL HOMOZYGOUS ASPM MUTATION ALONG WITH X-LINKED ICHTHYOSIS IN THE SAME PATIENT.

    Science.gov (United States)

    Abdel-Hamid, M S; Ismail, M F; Darwish, H A; Effat, L K; Zaki, M S; Abdel-Salam, G M H

    2016-01-01

    Autosomal recessive primary microcephaly is a heterogeneous genetic disorder caused by genes that affect neurogenesis. This form of microcephaly has not been associated with other congenital anomalies. ASPM mutations have been identified as the major cause implicated in autosomal recessive primary microcephaly. X-linked recessive ichthyosis, is an inborn error of steroid sulfatase metabolism characterized by dark and adhesive scaly skin. Here, we examined an Egyptian boy presenting with microcephaly and simplified gyral pattern. Additionally, he had ichthyosis that goes with the X-linked type. Mutation analyses of the ASPM gene for autosomal recessive primary microcephaly and STS gene of X-linked recessive ichthyosis were conducted revealing a co-occurrence of a novel homozygous splice site mutation of ASPM gene (c.2936+1G>A) and a partial deletion of STS spanning from exon 7-10. We propose that the phenotype of our patient results from the combined effects of mutations in both ASPM and STS that account for the neurological signs and skin manifestations, respectively. The association of isolated X-linked recessive ichthyosis and autosomal recessive primary microcephaly has never been reported in the literature. Careful clinical and genetic assessment of patients with atypical clinical phenotypes is crucial for detecting such rare double mutations and thus proper genetic counseling.

  3. Congenital IL-12R1β receptor deficiency and thrombophilia in a girl homozygous for an IL12RB1 mutation and compound heterozygous for MTFHR mutations: A case report and literature review

    OpenAIRE

    Akar, H. H.; Kose, M.; Ceylan, O.; Patiroglu, T.; Bustamante, J.; Casanova, J. L.; Akyildiz, B. N.; Doganay, S

    2014-01-01

    Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12Rβ1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She ...

  4. What is influencing the phenotype of the common homozygous polymerase-gamma mutation p.Ala467Thr?

    NARCIS (Netherlands)

    Neeve, V.C.; Samuels, D.C.; Bindoff, L.A.; Bosch, B. van den; Goethem, G. van; Smeets, H.; Lombes, A.; Jardel, C.; Hirano, M.; DiMauro, S.; Vries, M. de; Smeitink, J.; Smits, B.W.; Coo, I.F. de; Saft, C.; Klopstock, T.; Keiling, B.C.; Czermin, B.; Abicht, A.; Lochmuller, H.; Hudson, G.; Gorman, G.G.; Turnbull, D.M.; Taylor, R.W.; Holinski-Feder, E.; Chinnery, P.F.; Horvath, R.

    2012-01-01

    Polymerase-gamma (POLG) is a major human disease gene and may account for up to 25% of all mitochondrial diseases in the UK and in Italy. To date, >150 different pathogenic mutations have been described in POLG. Some mutations behave as both dominant and recessive alleles, but an autosomal

  5. PATIENTS WITH AUTOSOMAL NEPHROGENIC DIABETES-INSIPIDUS HOMOZYGOUS FOR MUTATIONS IN THE AQUAPORIN-2 WATER-CHANNEL GENE

    NARCIS (Netherlands)

    VANLIEBURG, AF; VERDIJK, MAJ; KNOERS, VVAM; VANESSEN, AJ; PROESMANS, W; MALLMANN, R; MONNENS, LAH; VANOOST, BA; VANOS, CH; DEEN, PMT

    1994-01-01

    Mutations in the X-chromosomal V2 receptor gene are known to cause nephrogenic diabetes insipidus (NDI). Besides the X-linked form, an autosomal mode of inheritance has been described. Recently, mutations in the autosomal gene coding for water-channel aquaporin 2 (AQP2) of the renal collecting duct

  6. Targeted next-generation sequencing identifies a homozygous nonsense mutation in ABHD12, the gene underlying PHARC, in a family clinically diagnosed with Usher syndrome type 3

    Directory of Open Access Journals (Sweden)

    Eisenberger Tobias

    2012-09-01

    Full Text Available Abstract Background Usher syndrome (USH is an autosomal recessive genetically heterogeneous disorder with congenital sensorineural hearing impairment and retinitis pigmentosa (RP. We have identified a consanguineous Lebanese family with two affected members displaying progressive hearing loss, RP and cataracts, therefore clinically diagnosed as USH type 3 (USH3. Our study was aimed at the identification of the causative mutation in this USH3-like family. Methods Candidate loci were identified using genomewide SNP-array-based homozygosity mapping followed by targeted enrichment and next-generation sequencing. Results Using a capture array targeting the three identified homozygosity-by-descent regions on chromosomes 1q43-q44, 20p13-p12.2 and 20p11.23-q12, we identified a homozygous nonsense mutation, p.Arg65X, in ABHD12 segregating with the phenotype. Conclusion Mutations of ABHD12, an enzyme hydrolyzing an endocannabinoid lipid transmitter, cause PHARC (polyneuropathy, hearing loss, ataxia, retinitis pigmentosa, and early-onset cataract. After the identification of the ABHD12 mutation in this family, one patient underwent neurological examination which revealed ataxia, but no polyneuropathy. ABHD12 is not known to be related to the USH protein interactome. The phenotype of our patient represents a variant of PHARC, an entity that should be taken into account as differential diagnosis for USH3. Our study demonstrates the potential of comprehensive genetic analysis for improving the clinical diagnosis.

  7. Posterior column ataxia with retinitis pigmentosa coexisting with sensory-autonomic neuropathy and leukemia due to the homozygous p.Pro221Ser FLVCR1 mutation.

    Science.gov (United States)

    Castori, Marco; Morlino, Silvia; Ungelenk, Martin; Pareyson, Davide; Salsano, Ettore; Grammatico, Paola; Tolosano, Emanuela; Kurth, Ingo; Chiabrando, Deborah

    2017-10-01

    FLVCR1 encodes for a ubiquitous heme exporter, whose recessive mutations cause posterior column ataxia with retinitis pigmentosa (PCARP). Recently, FLVCR1 recessive mutations were also found in two sporadic children with hereditary sensory-autonomic neuropathy (HSAN). We report the unique case of a 33-year-old Italian woman with a combination of typical PCARP, sensory-autonomic neuropathy with sensory loss to all modalities and multiple autonomic dysfuctions, and acute lymphocytic leukemia. Molecular analysis demonstrated homozygosity for the previously identified FLVCR1 p.Pro221Ser variation. The same variation, in combination with a frameshift mutation, was previously identified in an Italian child with HSAN. Functional studies carried out on patient-derived lymphoblastoid cell lines showed decreased FLVCR1a transcript, increased reactive oxygen species, excessive intracellular heme accumulation, and increased number of Annexin V positive cells. This indicates that the homozygous p.Pro221Ser FLVCR1 variation compromises the ability of FLVCR1a to export heme leading to enhanced susceptibility to programmed cell death. Our study demonstrates the existence of a phenotypic continuum among the discrete disorders previously linked to FLVCR1 mutations, and suggests that the related alteration of heme metabolism may lead to the degeneration of specific neuronal cell populations. © 2017 Wiley Periodicals, Inc.

  8. Distinct mutations led to inactivation of type 1 fimbriae expression in Shigella spp.

    Directory of Open Access Journals (Sweden)

    Verónica Bravo

    Full Text Available Shigella spp. are responsible for bacillary dysentery in humans. The acquisition or the modification of the virulence plasmid encoding factors promoting entry of bacteria into and dissemination within epithelial cells was a critical step in the evolution of these bacteria from their Escherichia coli ancestor(s. Incorporation of genomic islands (GI and gene inactivation also shaped interactions between these pathogens and their human host. Sequence analysis of the GI inserted next to the leuX tRNA gene in S. boydii, S. dysenteriae, S. flexneri, S. sonnei and enteroinvasive E. coli (EIEC suggests that this region initially carried the fec, yjhATS and fim gene clusters. The fim cluster encoding type I fimbriae is systematically inactivated in both reference strains and clinical isolates and distinct mutations are responsible for this inactivation in at least three phylogenetic groups. To investigate consequences of the presence of fimbriae on the outcome of the interaction of Shigella with host cells, we used a S. flexneri strain harboring a plasmid encoding the E. coli fim operon. Production of fimbriae by this recombinant strain increased the ability of bacteria to adhere to and enter into epithelial cells and had no effect on their ability to disseminate from cell to cell. The observations that production of type I fimbriae increases invasion of epithelial cells and that independent mutations abolish fimbriae production in Shigella suggest that these mutations correspond to pathoadaptive events.

  9. Distinct Mutations Led to Inactivation of Type 1 Fimbriae Expression in Shigella spp.

    Science.gov (United States)

    Bravo, Verónica; Puhar, Andrea; Sansonetti, Philippe; Parsot, Claude; Toro, Cecilia S.

    2015-01-01

    Shigella spp. are responsible for bacillary dysentery in humans. The acquisition or the modification of the virulence plasmid encoding factors promoting entry of bacteria into and dissemination within epithelial cells was a critical step in the evolution of these bacteria from their Escherichia coli ancestor(s). Incorporation of genomic islands (GI) and gene inactivation also shaped interactions between these pathogens and their human host. Sequence analysis of the GI inserted next to the leuX tRNA gene in S. boydii, S. dysenteriae, S. flexneri, S. sonnei and enteroinvasive E. coli (EIEC) suggests that this region initially carried the fec, yjhATS and fim gene clusters. The fim cluster encoding type I fimbriae is systematically inactivated in both reference strains and clinical isolates and distinct mutations are responsible for this inactivation in at least three phylogenetic groups. To investigate consequences of the presence of fimbriae on the outcome of the interaction of Shigella with host cells, we used a S. flexneri strain harboring a plasmid encoding the E. coli fim operon. Production of fimbriae by this recombinant strain increased the ability of bacteria to adhere to and enter into epithelial cells and had no effect on their ability to disseminate from cell to cell. The observations that production of type I fimbriae increases invasion of epithelial cells and that independent mutations abolish fimbriae production in Shigella suggest that these mutations correspond to pathoadaptive events. PMID:25811616

  10. Normal human adipose tissue functions and differentiation in patients with biallelic LPIN1 inactivating mutations.

    Science.gov (United States)

    Pelosi, Michele; Testet, Eric; Le Lay, Soazig; Dugail, Isabelle; Tang, Xiaoyun; Mabilleau, Guillaume; Hamel, Yamina; Madrange, Marine; Blanc, Thomas; Odent, Thierry; McMullen, Todd P W; Alfò, Marco; Brindley, David N; de Lonlay, Pascale

    2017-12-01

    Lipin-1 is a Mg2+-dependent phosphatidic acid phosphatase (PAP) that in mice is necessary for normal glycerolipid biosynthesis, controlling adipocyte metabolism, and adipogenic differentiation. Mice carrying inactivating mutations in the Lpin1 gene display the characteristic features of human familial lipodystrophy. Very little is known about the roles of lipin-1 in human adipocyte physiology. Apparently, fat distribution and weight is normal in humans carrying LPIN1 inactivating mutations, but a detailed analysis of adipose tissue appearance and functions in these patients has not been available so far. In this study, we performed a systematic histopathological, biochemical, and gene expression analysis of adipose tissue biopsies from human patients harboring LPIN1 biallelic inactivating mutations and affected by recurrent episodes of severe rhabdomyolysis. We also explored the adipogenic differentiation potential of human mesenchymal cell populations derived from lipin-1 defective patients. White adipose tissue from human LPIN1 mutant patients displayed a dramatic decrease in lipin-1 protein levels and PAP activity, with a concomitant moderate reduction of adipocyte size. Nevertheless, the adipose tissue develops without obvious histological signs of lipodystrophy and with normal qualitative composition of storage lipids. The increased expression of key adipogenic determinants such as SREBP1, PPARG, and PGC1A shows that specific compensatory phenomena can be activated in vivo in human adipocytes with deficiency of functional lipin-1. Copyright © 2017 by the American Society for Biochemistry and Molecular Biology, Inc.

  11. Patients with autosomal nephrogenic diabetes insipidus homozygous for mutations in the aquaporin 2 water-channel gene

    Energy Technology Data Exchange (ETDEWEB)

    Lieburg, A.F. van; Verdijk, M.A.J.; Knoers, V.V.A.M.; Monnens, L.A.H.; Oost, B.A. van; Os, C.H. van; Deen, P.M.T. [Univ. of Nijmegen (Netherlands); Essen, A.J. van [Univ. of Groningen (Netherlands); Proesmans, W. [Univ. of Leuven (Belgium); Mallmann, R. [Univ. of Bonn (Germany)

    1994-10-01

    Mutations in the X-chromosomal V2 receptor gene are known to cause nephrogenic diabetes insipidus (NDI). Besides the X-linked form, an autosomal mode of inheritance has been described. Recently, mutations in the autosomal gene coding for water-channel aquaporin 2 (AQP2) of the renal collecting duct were reported in an NDI patient. In the present study, missense mutations and a single nucleotide deletion in the aquaporin 2 gene of three NDI patients from consanquineous matings are described. Expression studies in Xenopus oocytes showed that the missense AQP2 proteins are nonfunctional. These results prove that mutations in the AQP2 gene cause autosomal recessive NDI. 32 refs., 4 figs.

  12. A homozygous mutation in the SCO2 gene causes a spinal muscular atrophy like presentation with stridor and respiratory insufficiency.

    Science.gov (United States)

    Pronicki, Maciej; Kowalski, Paweł; Piekutowska-Abramczuk, Dorota; Taybert, Joanna; Karkucinska-Wieckowska, Agnieszka; Szymanska-Debinska, Tamara; Karczmarewicz, Elzbieta; Pajdowska, Magdalena; Migdal, Marek; Milewska-Bobula, Bogumila; Sykut-Cegielska, Jolanta; Popowska, Ewa

    2010-05-01

    Infants with deficiency of cytochrome c oxidase (COX) due to SCO2 mutations observed so far usually demonstrated early cardiomyopathy, encephalopathy and lactic acidosis. Milder spinal muscular atrophy-like (SMA-like) phenotype was also rarely reported. The aim is to present 18 Polish patients with SCO2 mutations. Molecular study revealed p.E140K mutation in all cases (on 32 alleles); p.Q53X mutation and novel p.M177T change were identified in single patients. In three families no second mutation was found. Thirteen p.E140K homozygotes presented in infancy with floppiness and remarkable stridor. Survival motor neuron (SMN) gene deletion was excluded. Mild to moderate lactic academia was found. Neurological involvement manifested as spasticity and psychomotor retardation. In some patients strabismus, ptosis and episodes of seizures were seen. During second half of the year chronic respiratory failure with artificial respiration dependency appeared in all homozygotes. Heart involvement was never present at the beginning. Rapidly progressive hypertrophic cardiomyopathy developed in several patients at the terminal stage. The stridor was constant and striking feature. Skeletal muscle biopsy was performed in 16 patients including 11 homozygotes. Four pathological patterns were discerned - from neurogenic muscle changes, including spinal muscular atrophy (SMA) to unspecific findings. Histochemical cytochrome c oxidase (COX) deficit was not a constant feature. Significant decrease in respiratory chain complex IV activity was detected in muscle homogenate by spectrophotometric method only in 7 out of 12 examined cases. 1/Mutations of SCO2 gene should be considered as a possible cause of neurogenic skeletal muscle features (including SMA-like) in infants with encephalomyopathy even in the absence of heart involvement and COX deficit; 2/Inspiratory stridor may be symptomatic of SCO2 gene mutation(s). Copyright 2009 European Paediatric Neurology Society. Published by Elsevier

  13. Identification of a novel homozygous SPG7 mutation by whole exome sequencing in a Greek family with a complicated form of hereditary spastic paraplegia.

    Science.gov (United States)

    Daoud, Hussein; Papadima, Eleni Merkouri; Ouled Amar Bencheikh, Bouchra; Katsila, Theodora; Dionne-Laporte, Alexandre; Spiegelman, Dan; Dion, Patrick A; Patrinos, George P; Orrù, Sandro; Rouleau, Guy A

    2015-11-01

    We report the clinical description and genetic analyses of a Greek family with four individuals affected with a complicated form of hereditary spastic paraplegia (HSP) and a recessive pattern of inheritance. Exome sequencing of all affected individuals led to the identification of a homozygous 25 bp deletion predicted to lead to a frameshift and premature stop codon in the SPG7 gene, encoding paraplegin. This deletion, which is located in the first exon of the SPG7 gene, has not been previously reported and likely lead to the complete absence of the SPG7 protein. Interestingly, this family shows significant phenotypic heterogeneity further highlighting the clinical variability associated with SPG7 mutations. Our findings emphasize the clinical utility of whole exome sequencing for the molecular diagnosis of HSPs. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  14. A homozygous FITM2 mutation causes a deafness-dystonia syndrome with motor regression and signs of ichthyosis and sensory neuropathy

    Directory of Open Access Journals (Sweden)

    Celia Zazo Seco

    2017-02-01

    Full Text Available A consanguineous family from Pakistan was ascertained to have a novel deafness-dystonia syndrome with motor regression, ichthyosis-like features and signs of sensory neuropathy. By applying a combined strategy of linkage analysis and whole-exome sequencing in the presented family, a homozygous nonsense mutation, c.4G>T (p.Glu2*, in FITM2 was identified. FITM2 and its paralog FITM1 constitute an evolutionary conserved protein family involved in partitioning of triglycerides into cellular lipid droplets. Despite the role of FITM2 in neutral lipid storage and metabolism, no indications for lipodystrophy were observed in the affected individuals. In order to obtain independent evidence for the involvement of FITM2 in the human pathology, downregulation of the single Fitm ortholog, CG10671, in Drosophila melanogaster was pursued using RNA interference. Characteristics of the syndrome, including progressive locomotor impairment, hearing loss and disturbed sensory functions, were recapitulated in Drosophila, which supports the causative nature of the FITM2 mutation. Mutation-based genetic counseling can now be provided to the family and insight is obtained into the potential impact of genetic variation in FITM2.

  15. Forecasting the Long-Term Clinical and Economic Outcomes of Lumacaftor/Ivacaftor in Cystic Fibrosis Patients with Homozygous phe508del Mutation.

    Science.gov (United States)

    Dilokthornsakul, Piyameth; Patidar, Mausam; Campbell, Jonathan D

    2017-12-01

    To forecast lifetime outcomes and cost of lumacaftor/ivacaftor combination therapy in patients with cystic fibrosis (CF) with homozygous phe508del mutation from the US payer perspective. A lifetime Markov model was developed from a US payer perspective. The model included five health states: 1) mild lung disease (percent predicted forced expiratory volume in 1 second [FEV1] >70%), 2) moderate lung disease (40% ≤ FEV1 ≤ 70%), 3) severe lung disease (FEV1 < 40%), 4) lung transplantation, and 5) death. All inputs were derived from published literature. We estimated lumacaftor/ivacaftor's improvement in outcomes compared with a non-CF referent population as well as CF-specific mortality estimates. Lumacaftor/ivacaftor was associated with additional 2.91 life-years (95% credible interval 2.55-3.56) and additional 2.42 quality-adjusted life-years (QALYs) (95% credible interval 2.10-2.98). Lumacaftor/ivacaftor was associated with improvements in survival and QALYs equivalent to 27.6% and 20.7%, respectively, for the survival and QALY gaps between CF usual care and their non-CF peers. The incremental lifetime cost was $2,632,249. Lumacaftor/ivacaftor increased life-years and QALYs in CF patients with the homozygous phe508del mutation and moved morbidity and mortality closer to that of their non-CF peers but it came with higher cost. Copyright © 2017 International Society for Pharmacoeconomics and Outcomes Research (ISPOR). Published by Elsevier Inc. All rights reserved.

  16. An atypical case of familial glucocorticoid deficiency without pigmentation caused by coexistent homozygous mutations in MC2R (T152K) and MC1R (R160W).

    Science.gov (United States)

    Turan, Serap; Hughes, Claire; Atay, Zeynep; Guran, Tulay; Haliloglu, Belma; Clark, Adrian J L; Bereket, Abdullah; Metherell, Louise A

    2012-05-01

    Familial glucocorticoid deficiency (FGD) is a rare autosomal recessive disorder characterized by isolated cortisol deficiency. Mutations in the gene encoding the ACTH receptor (MC2R) account for 25% of cases. One significant feature is generalized skin hyperpigmentation, which is thought to be due to elevated ACTH acting on the melanocortin 1 receptor (MC1R). The aim of the study was to determine the cause of a nonhyperpigmented case of FGD. The patient presented at 4 yr of age with hypoglycemia after prolonged fasting during a respiratory tract infection. She had further hypoglycemic attacks and was diagnosed with isolated glucocorticoid deficiency at 6 yr of age. Her parents were consanguineous, and she had two unaffected sisters. Her physical examination was normal, except that her height and weight were greater than the 97th centile for a sex- and age-matched reference population. Interestingly, she had no hyperpigmentation despite very high ACTH levels. Nucleotide sequence analysis revealed homozygous mutations c.478C>T in MC1R and c.455C>A in MC2R leading to R160W and T152K changes in the amino acid sequences, respectively. The R160W MC1R change has previously been implicated in a red hair/pale skin phenotype, and MC2R -T152K is trafficking defective. Both parents and two unaffected sisters were heterozygous for the MC1R mutation; additionally, one unaffected sister was heterozygous for the MC2R mutation, and the other was wild-type. We report an unusual case of FGD without hyperpigmentation due to coexistent MC1R/MC2R mutations. This case is important because it demonstrates for the first time that the assumption that the action of ACTH on MC1R causes skin hyperpigmentation is correct.

  17. Cross-resistance patterns to ACCase-inhibitors in American sloughgrass (Beckmannia syzigachne Steud.) homozygous for specific ACCase mutations.

    Science.gov (United States)

    Du, Long; Liu, Weitang; Yuan, Guohui; Guo, Wenlei; Li, Qi; Wang, Jinxin

    2016-01-01

    American sloughgrass is a troublesome annual grass weed in winter wheat field rotated with rice in China. The overreliance on acetyl-coenzyme A carboxylase (ACCase) inhibiting herbicides has resulted in resistance evolution in this weed. In this study, the cross-resistance patterns to fenoxaprop-p-ethyl, clodinafop-propargyl, fluazifop-p-butyl, haloxyfop-p-methyl, sethoxydim, clethodim and pinoxaden were established using purified plants individually homozygous for specific mutant ACCase alleles. Results indicated that 1781Leu allele endows high-level resistance to APPs, CHDs and pinoxaden while confers moderate resistance to haloxyfop-p-methyl. The 2027Cys and 2041Asn alleles endow high-level resistance to APPs and pinoxaden and lower level resistance to CHDs. The 2078Gly allele confers high-level resistance to all herbicides tested in this study, however, moderate resistance to sethoxydim. The 2096Ala very likely endows high-level resistance to fluazifop-p-butyl, haloxyfop-p-methyl and moderate resistance to sethoxydim. In addition, one undefined resistance mechanism was involved in population SD-04. Copyright © 2015 Elsevier B.V. All rights reserved.

  18. Pregnancy-associated osteoporosis with a heterozygous deactivating LDL receptor-related protein 5 (LRP5) mutation and a homozygous methylenetetrahydrofolate reductase (MTHFR) polymorphism.

    Science.gov (United States)

    Cook, Fiona J; Mumm, Steven; Whyte, Michael P; Wenkert, Deborah

    2014-04-01

    Pregnancy-associated osteoporosis (PAO) is a rare, idiopathic disorder that usually presents with vertebral compression fractures (VCFs) within 6 months of a first pregnancy and delivery. Spontaneous improvement is typical. There is no known genetic basis for PAO. A 26-year-old primagravida with a neonatal history of unilateral blindness attributable to hyperplastic primary vitreous sustained postpartum VCFs consistent with PAO. Her low bone mineral density (BMD) seemed to respond to vitamin D and calcium therapy, with no fractures after her next successful pregnancy. Investigation of subsequent fetal losses revealed homozygosity for the methylenetetrahydrofolate reductase (MTHFR) C677T polymorphism associated both with fetal loss and with osteoporosis (OP). Because her neonatal unilateral blindness and OP were suggestive of loss-of-function mutation(s) in the gene that encodes LDL receptor-related protein 5 (LRP5), LRP5 exon and splice site sequencing was also performed. This revealed a unique heterozygous 12-bp deletion in exon 21 (c.4454_4465del, p.1485_1488del SSSS) in the patient, her mother and sons, but not her father or brother. Her mother had a normal BMD, no history of fractures, PAO, ophthalmopathy, or fetal loss. Her two sons had no ophthalmopathy and no skeletal issues. Her osteoporotic father (with a family history of blindness) and brother had low BMDs first documented at ages ∼40 and 32 years, respectively. Serum biochemical and bone turnover studies were unremarkable in all subjects. We postulate that our patient's heterozygous LRP5 mutation together with her homozygous MTHFR polymorphism likely predisposed her to low peak BMD. However, OP did not cosegregate in her family with the LRP5 mutation, the homozygous MTHFR polymorphism, or even the combination of the two, implicating additional genetic or nongenetic factors in her PAO. Nevertheless, exploration for potential genetic contributions to PAO may explain part of the pathogenesis of this

  19. Compound heterozygous or homozygous truncating MYBPC3 mutations cause lethal cardiomyopathy with features of noncompaction and septal defects

    NARCIS (Netherlands)

    Wessels, Marja W.; Herkert, Johanna C.; Frohn-Mulder, Ingrid M.; Dalinghaus, Michiel; van den Wijngaard, Arthur; de Krijger, Ronald R.; Michels, Michelle; de Coo, Irenaeus F. M.; Hoedemaekers, Yvonne M.; Dooijes, Dennis

    Familial hypertrophic cardiomyopathy (HCM) is usually caused by autosomal dominant pathogenic mutations in genes encoding sarcomeric or sarcomere-associated cardiac muscle proteins. The disease mainly affects adults, although young children with severe HCM have also been reported. We describe four

  20. Compound heterozygous or homozygous truncating MYBPC3 mutations cause lethal cardiomyopathy with features of noncompaction and septal defects

    NARCIS (Netherlands)

    Wessels, Marja W.; Herkert, Johanna C.; Frohn-Mulder, Ingrid M.; Dalinghaus, Michiel; Van Den Wijngaard, Arthur; De Krijger, Ronald R.; Michels, Michelle; De Coo, Irenaeus Fm; Hoedemaekers, Yvonne M.; Dooijes, Dennis

    2015-01-01

    Familial hypertrophic cardiomyopathy (HCM) is usually caused by autosomal dominant pathogenic mutations in genes encoding sarcomeric or sarcomere-associated cardiac muscle proteins. The disease mainly affects adults, although young children with severe HCM have also been reported. We describe four

  1. Whole-exome sequencing identifies homozygous AFG3L2 mutations in a spastic ataxia-neuropathy syndrome linked to mitochondrial m-AAA proteases.

    Directory of Open Access Journals (Sweden)

    Tyler Mark Pierson

    2011-10-01

    Full Text Available We report an early onset spastic ataxia-neuropathy syndrome in two brothers of a consanguineous family characterized clinically by lower extremity spasticity, peripheral neuropathy, ptosis, oculomotor apraxia, dystonia, cerebellar atrophy, and progressive myoclonic epilepsy. Whole-exome sequencing identified a homozygous missense mutation (c.1847G>A; p.Y616C in AFG3L2, encoding a subunit of an m-AAA protease. m-AAA proteases reside in the mitochondrial inner membrane and are responsible for removal of damaged or misfolded proteins and proteolytic activation of essential mitochondrial proteins. AFG3L2 forms either a homo-oligomeric isoenzyme or a hetero-oligomeric complex with paraplegin, a homologous protein mutated in hereditary spastic paraplegia type 7 (SPG7. Heterozygous loss-of-function mutations in AFG3L2 cause autosomal-dominant spinocerebellar ataxia type 28 (SCA28, a disorder whose phenotype is strikingly different from that of our patients. As defined in yeast complementation assays, the AFG3L2(Y616C gene product is a hypomorphic variant that exhibited oligomerization defects in yeast as well as in patient fibroblasts. Specifically, the formation of AFG3L2(Y616C complexes was impaired, both with itself and to a greater extent with paraplegin. This produced an early-onset clinical syndrome that combines the severe phenotypes of SPG7 and SCA28, in additional to other "mitochondrial" features such as oculomotor apraxia, extrapyramidal dysfunction, and myoclonic epilepsy. These findings expand the phenotype associated with AFG3L2 mutations and suggest that AFG3L2-related disease should be considered in the differential diagnosis of spastic ataxias.

  2. Neonatal severe hyperparathyroidism caused by homozygous mutation in CASR: A rare cause of life-threatening hypercalcemia.

    Science.gov (United States)

    Murphy, Heidi; Patrick, Jessica; Báez-Irizarry, Eileen; Lacassie, Yves; Gómez, Ricardo; Vargas, Alfonso; Barkemeyer, Brian; Kanotra, Sohit; Zambrano, Regina M

    2016-04-01

    Neonatal severe hyperparathyroidism (NSHPT) is a rare, life-threatening condition that presents with severe hypercalcemia, hyperparathyroidism, and osteopenia in the newborn period. Treatment of NSHPT traditionally includes hydration and bisphosphonates; however newer calcimimetic agents, such as cinacalcet, are now being utilized to prevent or delay parathyroidectomy which is technically difficult in the newborn. Medical treatment success is related to calcium sensing receptor (CaSR) genotype. We report a 4-day-old infant who presented with hyperbilirubinemia, poor feeding, weight loss, severe hypotonia and was ultimately diagnosed with NSHPT. The patient's total serum calcium level of 36.8 mg/dL (reference range: 8.5-10.4 mg/dL) is, to our knowledge, the highest ever documented in this setting. Exome data previously obtained on the infant's parents was re-analyzed demonstrating bi-parental heterozygosity for a mutation of the CASR gene: c.206G > A, and Sanger sequencing data confirmed the patient was a homozygote for the same mutation. Though a patient with the same CaSR gene mutation described here has responded to cinacalcet, our patient did not respond and required parathyroidectomy. Though this case has previously been published as a surgical case report, a full report of the medical management and underlying genetic etiology is warranted; this case underscores the importance of disclosing bi-parental heterozygosity for a gene causing severe neonatal disease particularly when treatment is available and illustrates the need for further in vitro studies of this CaSR mutation. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  3. A novel homozygous p.R1105X mutation of the AP4E1 gene in twins with hereditary spastic paraplegia and mycobacterial disease.

    Directory of Open Access Journals (Sweden)

    Xiao-Fei Kong

    Full Text Available We report identical twins with intellectual disability, progressive spastic paraplegia and short stature, born to a consanguineous family. Intriguingly, both children presented with lymphadenitis caused by the live Bacillus Calmette-Guérin (BCG vaccine. Two syndromes - hereditary spastic paraplegia (HSP and mycobacterial disease - thus occurred simultaneously. Whole-exome sequencing (WES revealed a homozygous nonsense mutation (p.R1105X of the AP4E1 gene, which was confirmed by Sanger sequencing. The p.R1105X mutation has no effect on AP4E1 mRNA levels, but results in lower levels of AP-4ε protein and of the other components of the AP-4 complex, as shown by western blotting, immunoprecipitation and immunofluorescence. Thus, the C-terminal part of the AP-4ε subunit plays an important role in maintaining the integrity of the AP-4 complex. No abnormalities of the IL-12/IFN-γ axis or oxidative burst pathways were identified. In conclusion, we identified twins with autosomal recessive AP-4 deficiency associated with HSP and mycobacterial disease, suggesting that AP-4 may play important role in the neurological and immunological systems.

  4. Donnai-Barrow syndrome (DBS/FOAR) in a child with a homozygous LRP2 mutation due to complete chromosome 2 paternal isodisomy.

    Science.gov (United States)

    Kantarci, Sibel; Ragge, Nicola K; Thomas, N Simon; Robinson, David O; Noonan, Kristin M; Russell, Meaghan K; Donnai, Dian; Raymond, F Lucy; Walsh, Christopher A; Donahoe, Patricia K; Pober, Barbara R

    2008-07-15

    Donnai-Barrow syndrome [Faciooculoacousticorenal (FOAR) syndrome; DBS/FOAR] is a rare autosomal recessive disorder resulting from mutations in the LRP2 gene located on chromosome 2q31.1. We report a unique DBS/FOAR patient homozygous for a 4-bp LRP2 deletion secondary to paternal uniparental isodisomy for chromosome 2. The propositus inherited the mutation from his heterozygous carrier father, whereas the mother carried only wild-type LRP2 alleles. This is the first case of DBS/FOAR resulting from uniparental disomy (UPD) and the fourth published case of any paternal UPD 2 ascertained through unmasking of an autosomal recessive disorder. The absence of clinical symptoms above and beyond the classical phenotype in this and the other disorders suggests that paternal chromosome 2 is unlikely to contain imprinted genes notably affecting either growth or development. This report highlights the importance of parental genotyping in order to give accurate genetic counseling for autosomal recessive disorders. 2008 Wiley-Liss, Inc.

  5. Donnai–Barrow Syndrome (DBS/FOAR) in a Child With a Homozygous LRP2 Mutation Due to Complete Chromosome 2 Paternal Isodisomy

    Science.gov (United States)

    Kantarci, Sibel; Ragge, Nicola K.; Thomas, N. Simon; Robinson, David O.; Noonan, Kristin M.; Russell, Meaghan K.; Donnai, Dian; Raymond, F. Lucy; Walsh, Christopher A.; Donahoe, Patricia K.; Pober, Barbara R.

    2010-01-01

    Donnai–Barrow syndrome [Faciooculoacousticorenal (FOAR) syndrome; DBS/FOAR] is a rare autosomal recessive disorder resulting from mutations in the LRP2 gene located on chromosome 2q31.1. We report a unique DBS/FOAR patient homozygous for a 4-bp LRP2 deletion secondary to paternal uniparental isodisomy for chromosome 2. The propositus inherited the mutation from his heterozygous carrier father, whereas the mother carried only wild-type LRP2 alleles. This is the first case of DBS/FOAR resulting from uniparental disomy (UPD) and the fourth published case of any paternal UPD 2 ascertained through unmasking of an autosomal recessive disorder. The absence of clinical symptoms above and beyond the classical phenotype in this and the other disorders suggests that paternal chromosome 2 is unlikely to contain imprinted genes notably affecting either growth or development. This report highlights the importance of parental genotyping in order to give accurate genetic counseling for autosomal recessive disorders. PMID:18553518

  6. Genetics of suspected thrombophilia in Serbian females with infertility, including three cases, homozygous for FII 20210A or FV 1691A mutations.

    Science.gov (United States)

    Djurovic, Jelena; Stojkovic, Oliver; Todorovic, Jelena; Brajic, Aleksandra; Stankovic, Sanja; Obradovic, Svetlana; Stamenkovic, Gorana

    2017-06-01

    Reproductive failure (recurrent foetal loss, unexplained infertility and IVF implantation failure) may be, in a number of cases, explained by thrombophilia, either acquired or inherited. Several genes contribute to thrombophilia, some with major effect (Factor V, Factor II), and some with minor effect (MTHFR, PAI-1, ATIII, etc.). The aim of this study was to estimate frequency of thrombophilia-associated genotypes (FII20210G > A, FV1691G > A, MTHFR677C > T and PAI-1 -675 4G/5G) in a group of 1631 Serbian women experiencing reproductive failure, and compare it with a healthy, female control group. Our results showed marginally significant (p = 0.050) differences in allele frequencies between patients and controls for the FV1691 mutations. For the FII20210G > A, although the statistical significance was not achieved (p = 0.076), we found higher frequency of variant allele in patients compared to controls (1.87% vs. 0.38%, respectively) which may point to a possible role of this polymorphism in thrombotic events. For the MTHFR677C > T and PAI-1 -675 4G/5G, we found no difference in distributions of genotype or allele frequencies between these two groups (p > 0.05). For three subjects with very rare genotypes (two patients homozygous for FV1691G > A and one patient homozygous for FII20210G > A) we performed additional biochemical analyses for haemostasis, as well as genotyping of two polymorphisms (MTHFR1298A > C and ATIII786G > A).

  7. Congenital IL-12R1β receptor deficiency and thrombophilia in a girl homozygous for an IL12RB1 mutation and compound heterozygous for MTFHR mutations: A case report and literature review.

    Science.gov (United States)

    Akar, H H; Kose, M; Ceylan, O; Patiroglu, T; Bustamante, J; Casanova, J L; Akyildiz, B N; Doganay, S

    2014-03-01

    Interleukin-12 (IL-12) plays an important role in the production of interferon gamma from T cells and natural killer cells and is essential for protection against intra-macrophagic pathogens such as Mycobacterium and Salmonella. Here, we describe a 16-year-old girl with homozygous mutation in exon 12 of the IL12RB1 gene, which causes complete IL-12Rβ1 deficiency in association with heterozygous mutation (C677T and A1298C) in the methylenetetrahydrofolate reductase gene. She presented with disseminated Mycobacterium tuberculosis complex infection, retroperitoneal fungal abscess and also thrombosis in the superior mesenteric-portal vein junction. This is the first case report of a primary immunodeficiency associated with a genetically determined venous thrombosis.

  8. A homozygous ZMPSTE24 null mutation in combination with a heterozygous mutation in the LMNA gene causes Hutchinson-Gilford progeria syndrome (HGPS): insights into the pathophysiology of HGPS.

    Science.gov (United States)

    Denecke, Jonas; Brune, Thomas; Feldhaus, Tobias; Robenek, Horst; Kranz, Christian; Auchus, Richard J; Agarwal, Anil K; Marquardt, Thorsten

    2006-06-01

    Hutchinson-Gilford progeria syndrome (HGPS) is a rare premature aging disorder normally caused by a spontaneous heterozygous mutation in the LMNA gene that codes for the nuclear lamina protein lamin A. Several enzymes are involved in the processing of its precursor, prelamin A, to the mature lamin A. A functional knockout of one of the enzymes involved in prelamin A processing, the zinc metalloprotease ZMPSTE24, causes an even more severe disorder with early neonatal death described as restrictive dermatopathy (RD). This work describes a HGPS patient with a combined defect of a homozygous loss-of-function mutation in the ZMPSTE24 gene and a heterozygous mutation in the LMNA gene that results in a C-terminal elongation of the final lamin A. Whereas the loss of function mutation of ZMPSTE24 normally results in lethal RD, the truncation of LMNA seems to be a salvage alteration alleviating the clinical picture to the HGPS phenotype. The mutations of our patient indicate that farnesylated prelamin A is the deleterious agent leading to the HGPS phenotype, which gives further insights into the pathophysiology of the disorder. Copyright 2006 Wiley-Liss, Inc.

  9. Homozygous inactivation of CHEK2 is linked to a familial case of multiple primary lung cancer with accompanying cancers in other organs

    OpenAIRE

    Kukita, Yoji; OKAMI, JIRO; Yoneda-Kato, Noriko; Nakamae, Ikuko; Kawabata, Takeshi; Higashiyama, Masahiko; Kato, Junya; Kodama, Ken; Kato, Kikuya

    2016-01-01

    In clinical practice, there are a number of cancer patients with clear family histories, but the patients lack mutations in known familial cancer syndrome genes. Recent advances in genomic technologies have enhanced the possibility of identifying causative genes in such cases. Two siblings, an elder sister and a younger brother, were found to have multiple primary lung cancers at the age of 60. The former subsequently developed breast cancer and had a history of uterine myoma. The latter had ...

  10. Furosemide loading test in a case of homozygous solute carrier family 12, member 1 (SLC12A1) mutation (g.62382825G>A, p.Pro372Leu) in Japanese Black cattle.

    Science.gov (United States)

    Hasegawa, Kiyotoshi; Sasaki, Shinji; Sakamoto, Yoichi; Takano, Akifumi; Takayama, Megumi; Higashi, Tomoko; Sugimoto, Yoshikazu; Yasuda, Yasuaki

    2017-10-01

    Hydrallantois is the excessive accumulation of fluid in the allantoic cavity in a pregnant animal and is associated with fetal death. We recently identified a recessive missense mutation in the solute carrier family 12, member 1 (SLC12A1) gene (g.62382825G>A, p.Pro372Leu) that is associated with hydrallantois in Japanese Black cattle. Unexpectedly, we found a case of the homozygous risk-allele for SLC12A1 in a calf, using a PCR-based direct DNA sequencing test. The homozygote was outwardly healthy up to 3 months of age and the mother did not exhibit any clinical symptoms of hydrallantois. In order to validate these observations, we performed confirmation tests for the genotype and a diuretic loading test using furosemide, which inhibits the transporter activity of the SLC12A1 protein. The results showed that the calf was really homozygous for the risk-allele. In the homozygous calf, administration of furosemide did not alter urinary Na + or Cl - levels, in contrast to the heterozygote and wild-type calves in which these were significantly increased. These results demonstrate that the SLC12A1 (g.62382825G>A, p.Pro372Leu) is a hypomorphic or loss-of-function mutation and the hydrallantois with this mutation shows incomplete penetrance in Japanese Black cattle. © 2017 Japanese Society of Animal Science.

  11. The phenotype of polycythemia due to Croatian homozygous VHL (571C>G:H191D) mutation is different from that of Chuvash polycythemia (VHL 598C>T:R200W).

    Science.gov (United States)

    Tomasic, Nikica Ljubas; Piterkova, Lucie; Huff, Chad; Bilic, Ernest; Yoon, Donghoon; Miasnikova, Galina Y; Sergueeva, Adelina I; Niu, Xiaomei; Nekhai, Sergei; Gordeuk, Victor; Prchal, Josef T

    2013-04-01

    Mutations of VHL (a negative regulator of hypoxia-inducible factors) have position-dependent distinct cancer phenotypes. Only two known inherited homozygous VHL mutations exist and they cause polycythemia: Chuvash R200W and Croatian H191D. We report a second polycythemic Croatian H191D homozygote distantly related to the first propositus. Three generations of both families were genotyped for analysis of shared ancestry. Biochemical and molecular tests were performed to better define their phenotypes, with an emphasis on a comparison with Chuvash polycythemia. The VHL H191D mutation did not segregate in the family defined by the known common ancestors of the two subjects, suggesting a high prevalence in Croatians, but haplotype analysis indicated an undocumented common ancestor ∼six generations ago as the founder of this mutation. We show that erythropoietin levels in homozygous VHL H191D individuals are higher than in VHL R200W patients of similar ages, and their native erythroid progenitors, unlike Chuvash R200W, are not hypersensitive to erythropoietin. This observation contrasts with a report suggesting that polycythemia in VHL R200W and H191D homozygotes is due to the loss of JAK2 regulation from VHL R200W and H191D binding to SOCS1. In conclusion, our studies further define the hematologic phenotype of VHL H191D and provide additional evidence for phenotypic heterogeneity associated with the positional effects of VHL mutations.

  12. X-linked sideroblastic anemia associated with a novel ALAS2 mutation and unfortunate skewed X-chromosome inactivation patterns.

    Science.gov (United States)

    Aivado, Manuel; Gattermann, Norbert; Rong, Astrid; Giagounidis, Aristoteles A N; Prall, Wolf C; Czibere, Akos; Hildebrandt, Barbara; Haas, Rainer; Bottomley, Sylvia S

    2006-01-01

    Historically X-linked sideroblastic anemia, with rare exceptions, was thought to be manifested only in males. Since the discovery of the erythroid-specific isoform of 5-aminolevulinate synthase (ALAS2) and the cloning of its gene (ALAS2) 15 years ago, mutation analysis has revealed that clinical expression of this X-linked disorder is prevalent in females as well. However, presence of the disease in both genders within affected kindreds appears to be very uncommon. We report a unique family with the disorder in three women who have had widely disparate clinical courses. The anemia is associated with a previously unrecognized ALAS2 mutation (Arg436Trp) and is unresponsive to pyridoxine. To clarify the varied clinical courses of the patients, X-chromosome inactivation patterns were examined in hematopoietic and non-hematopoietic cells. We observed inactivation patterns supporting the conclusions that one daughter has a mild phenotype at age 31 because of moderate constitutive skewed X-chromosome inactivation, another daughter with clinical onset at age 16 is severely affected due to extreme constitutive X-skewing, whereas the mother developed progressive anemia in the fifth decade as she acquired an age-related non-random X-inactivation in hematopoietic cells. In addition, we observed random X-inactivation in reticulocytes of all three women that contrasted with a markedly skewed inactivation pattern in bone marrow erythroid cells. This discordance is attributable to apoptosis of erythroid precursors derived from progenitor cells with an active X-chromosome bearing the ALAS2 mutation. The features of the disorder in this family are also instructive in regard to the differential diagnosis of sideroblastic anemias in women.

  13. Accelerated inactivation of the L-type calcium current due to a mutation in CACNB2b underlies Brugada syndrome

    DEFF Research Database (Denmark)

    Cordeiro, Jonathan M; Marieb, Mark; Pfeiffer, Ryan

    2009-01-01

    S in which loss of function is caused by accelerated inactivation of I(Ca). The proband, a 32 year old male, displayed a Type I ST segment elevation in two right precordial ECG leads following a procainamide challenge. EP study was positive with induction of polymorphic VT/VF. Interrogation of implanted ICD...... significantly faster in mutant channels between 0 and + 20 mV. Action potential voltage clamp experiments showed that total charge was reduced by almost half compared to WT. We report the first BrS mutation in CaCNB2b resulting in accelerated inactivation of L-type calcium channel current. Our results suggest...

  14. Ocular findings in adult subjects with an inactivating mutation in GH releasing hormone receptor gene.

    Science.gov (United States)

    Faro, Augusto C N; Pereira-Gurgel, Virginia M; Salvatori, Roberto; Campos, Viviane C; Melo, Gustavo B; Oliveira, Francielle T; Oliveira-Santos, Alecia A; Oliveira, Carla R P; Pereira, Francisco A; Hellström, Ann; Oliveira-Neto, Luís A; Valença, Eugenia H O; Aguiar-Oliveira, Manuel H

    2017-06-01

    Ocular function is fundamental for environmental adaptation and survival capacity. Growth factors are necessary for a mature eyeball, needed for adequate vision. However, the consequences of the deficiency of circulating growth hormone (GH) and its effector insulin-like growth factor I (IGF-I) on the physical aspects of the human eye are still debated. A model of untreated isolated GH deficiency (IGHD), with low but measurable serum GH, may clarify this issue. The aim of this study was to assess the ocular aspects of adult IGHD individuals who have never received GH therapy. Cross sectional study. Setting: University Hospital, Federal University of Sergipe, Brazil. Twenty-five adult (13 males, mean age 50.1years, range 26 to 70years old) IGHD subjects homozygous for a null mutation (c.57+1G>A) in the GHRH receptor gene, and 28 (15 males, mean age 51.1years, range 26 to 67years old) controls were submitted to an endocrine and ophthalmological assessment. Forty-six IGHD and 50 control eyes were studied. Visual acuity, intraocular pressure, refraction (spherical equivalent), ocular axial length (AL), anterior chamber depth (ACD), lens thickness (LT), vitreous depth (VD), mean corneal curvature (CC) and central corneal thickness (CCT). IGHD subjects exhibited unmeasurable serum IGF-I levels, similar visual acuity, intraocular pressure and LT, higher values of spherical equivalent and CC, and lower measures of AL, ACD, VD and CCT in comparison to controls, but within their respective normal ranges. While mean stature in IGHD group was 78% of the control group, mean head circumference was 92% and axial AL was 96%. These observations suggest mild ocular effects in adult subjects with severe IGF-I deficiency due to non-treated IGHD. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. A homozygous FITM2 mutation causes a deafness-dystonia syndrome with motor regression and signs of ichthyosis and sensory neuropathy

    DEFF Research Database (Denmark)

    Zazo Seco, Celia; Castells-Nobau, Anna; Joo, Seol-Hee

    2017-01-01

    A consanguineous family from Pakistan was ascertained to have a novel deafness-dystonia syndrome with motor regression, ichthyosis-like features and signs of sensory neuropathy. By applying a combined strategy of linkage analysis and whole-exome sequencing in the presented family, a homozygous no...

  16. Setleis syndrome in Mexican-Nahua sibs due to a homozygous TWIST2 frameshift mutation and partial expression in heterozygotes: review of the focal facial dermal dysplasias and subtype reclassification.

    Science.gov (United States)

    Cervantes-Barragán, David E; Villarroel, Camilo E; Medrano-Hernández, Alma; Durán-McKinster, Carola; Bosch-Canto, Vanessa; Del-Castillo, Victoria; Nazarenko, Irina; Yang, Amy; Desnick, Robert J

    2011-10-01

    The focal facial dermal dysplasias (FFDDs) are a group of inherited disorders of facial development, characterised by bitemporal or preauricular scar-like defects, the former resembling 'forceps marks'. Recently, different homozygous TWIST2 nonsense mutations were reported in unrelated Setleis syndrome (FFDD Type III) patients from consanguineous families, consistent with autosomal recessive inheritance. Mexican-Nahua sibs with facial and ophthalmologic features of FFDD type III were evaluated. Genomic DNAs were isolated for sequencing of the TWIST2 gene. The clinical features and inheritance of all previously reported FFDD patients were reviewed. The affected sibs were homozygous for a novel TWIST2 frameshift mutation, c.168delC (p.S57AfsX45). Notably, both parents and two heterozygous sibs had distichiasis and partial absence of lower eyelashes. The FFDD subtypes were reclassified: the 'Brauer-Setleis' phenotype (autosomal dominant with variable expressivity) as FFDD type II; and patients with preauricular lesions as a new subtype, FFDD type IV. FFDD type III heterozygotes with TWIST2 mutations may have syndromic manifestations. Review of previous FFDD patients resulted in reclassification of the subtypes.

  17. Individuals who are homozygous for the 2282del4 and R501X filaggrin null mutations do not always develop dermatitis and complete long-term remission is possible

    DEFF Research Database (Denmark)

    Thyssen, Jp; Carlsen, Bc; Bisgaard, H

    2012-01-01

    Background About 8-10% of the general population in Europe carry a null mutation in the filaggrin gene which is associated with early onset of atopic dermatitis as well as persistence into adulthood. No studies have investigated whether individuals with the homozygous filaggrin null genotype always...... health examination; (ii) a total of 499 patients seen in our dermatitis clinic since 2009 and who were filaggrin genotyped as a part of the routine diagnostic work up; and (iii) a prospective, longitudinal, birth cohort study of 411 children born to mothers with a history of asthma. Filaggrin genotyping...

  18. Oculocutaneous albinism type 2 (OCA2) with homozygous 2.7-kb deletion of the P gene and sickle cell disease in a Cameroonian family. Identification of a common TAG haplotype in the mutated P gene.

    Science.gov (United States)

    Aquaron, Robert; Soufir, Nadem; Bergé-Lefranc, Jean-Louis; Badens, Catherine; Austerlitz, Frederic; Grandchamp, Bernard

    2007-01-01

    In this study, we report on a Cameroonian family from the Ewondo ethnic group, presenting with three oculocutaneous albinism type 2 (OCA2) patients homozygous for the 2.7-kb deletion of the P gene. In one of these patients OCA2 was associated with sickle cell anaemia and in two with the sickle cell trait. We took this opportunity to determine single nucleotide polymorphism (SNP) haplotypes within the P gene in this family in comparison with a group of 53 OCA2 patients homozygous for the same mutation and with a matched unrelated full-coloured control group of 49 subjects, originating from seven different ethnic groups of Southern Cameroon including Ewondo. A combination of five exonic and intronic SNPs in the OCA2 gene was genotyped by sequencing PCR products. We found 3 different haplotypes (TAGCT, TAGTT and TAGCC with frequencies of 0.66, 0.28 and 0.06, respectively) associated with the mutation in the 53 OCA2 patients, while 11 different haplotypes were observed in the control group. These observations suggest that the mutation appeared on the relatively frequent haplotype TAGCT, and that the two other haplotypes are derived from two independent recombination events. These haplotypic data, associated with a value of 1/15,000 for the prevalence of the 2.7-kb mutation, a present effective population size of 10,000,000 for Cameroon and a recombination rate of 0.0031, allowed us to estimate that this mutation originated 4,100-5,645 years ago.

  19. Generation of induced pluripotent stem cells (iPSCs from a hereditary spastic paraplegia patient carrying a homozygous R486C mutation in CYP7B1 (SPG5

    Directory of Open Access Journals (Sweden)

    Philip Höflinger

    2016-09-01

    Full Text Available Skin fibroblasts were obtained from a 47-year-old hereditary spastic paraplegia patient carrying a homozygous mutation R486C in CYP7B1 (Cytochrome P450, Family 7, Subfamily B, Polypeptide 1, responsible for causing hereditary spastic paraplegia type 5 (SPG5. Induced pluripotent stem cells (iPSCs were generated by transfection with episomal plasmids carrying hOCT4, hSOX2, hKLF4, hL-MYC and hLIN28. The generated line iPS-SPG5-R486C was transgene-free, retained the specific mutation with no additional genomic aberrations, expressed pluripotency markers and was able to differentiate into cells of all germ layers in vitro. The generated iPS-SPG5-R486C line may be a useful resource for disease modelling of SPG5.

  20. Generation of induced pluripotent stem cells (iPSCs from a hereditary spastic paraplegia patient carrying a homozygous Y275X mutation in CYP7B1 (SPG5

    Directory of Open Access Journals (Sweden)

    Stefan Hauser

    2016-09-01

    Full Text Available Skin fibroblasts were obtained from a 47-year-old hereditary spastic paraplegia patient carrying a homozygous mutation Y275X in CYP7B1 (Cytochrome P450, Family 7, Subfamily B, Polypeptide 1, responsible for causing hereditary spastic paraplegia type 5 (SPG5. Induced pluripotent stem cells (iPSCs were generated by transfection with episomal plasmids carrying hOCT4, hSOX2, hKLF4, hL-MYC and hLIN28. The generated line iPS-SPG5-Y275X was transgene-free, retained the specific mutation with no additional genomic aberrations, expressed pluripotency markers and was able to differentiate into cells of all germ layers in vitro. The generated iPS-SPG5-Y275X line may be a useful resource for disease modelling of SPG5.

  1. A Kir6.2 pore mutation causes inactivation of ATP-sensitive potassium channels by disrupting PIP2-dependent gating.

    Directory of Open Access Journals (Sweden)

    Jeremy D Bushman

    Full Text Available In the absence of intracellular nucleotides, ATP-sensitive potassium (KATP channels exhibit spontaneous activity via a phosphatidylinositol-4,5-bisphosphate (PIP2-dependent gating process. Previous studies show that stability of this activity requires subunit-subunit interactions in the cytoplasmic domain of Kir6.2; selective mutagenesis and disease mutations at the subunit interface result in time-dependent channel inactivation. Here, we report that mutation of the central glycine in the pore-lining second transmembrane segment (TM2 to proline in Kir6.2 causes KATP channel inactivation. Unlike C-type inactivation, a consequence of selectivity filter closure, in many K(+ channels, the rate of inactivation in G156P channels was insensitive to changes in extracellular ion concentrations or ion species fluxing through the pore. Instead, the rate of G156P inactivation decreased with exogenous application of PIP2 and increased when PIP2-channel interaction was inhibited with neomycin or poly-L-lysine. These findings indicate the G156P mutation reduces the ability of PIP2 to stabilize the open state of KATP channels, similar to mutations in the cytoplasmic domain that produce inactivation. Consistent with this notion, when PIP2-dependent open state stability was substantially increased by addition of a second gain-of-function mutation, G156P inactivation was abolished. Importantly, bath application and removal of Mg(2+-free ATP or a nonhydrolyzable analog of ATP, which binds to the cytoplasmic domain of Kir6.2 and causes channel closure, recover G156P channel from inactivation, indicating crosstalk between cytoplasmic and transmembrane domains. The G156P mutation provides mechanistic insight into the structural and functional interactions between the pore and cytoplasmic domains of Kir6.2 during gating.

  2. Life-long course and molecular characterization of the original Dutch family with epidermolysis bullosa simplex with muscular dystrophy due to a homozygous novel plectin point mutation

    NARCIS (Netherlands)

    Koss-Harnes, D; Hoyheim, B; Jonkman, MF; De Groot, WP; De Weerdt, CJ; Nikolic, B; Wiche, G; Gedde-Dahl, T

    Plectin is one of the largest and most versatile cytolinker proteins known. Cloned and sequenced in 1991, it was later shown to have nonsense mutations in recessive epidermolysis bullosa with muscular dystrophy. A dominant mutation in the gene was found to cause epidermolysis bullosa simplex Ogna

  3. Crohn's disease patients homozygous for the 3020insC NOD2 mutation have a defective NOD2/TLR4 cross-tolerance to intestinal stimuli.

    NARCIS (Netherlands)

    Kullberg, B.J.; Ferwerda, G.; Jong, D.J. de; Drenth, J.P.H.; Joosten, L.A.B.; Meer, J.W.M. van der; Netea, M.G.

    2008-01-01

    Mutations in nucleotide-binding oligomerization domain-2 (NOD2), leading to defective recognition of bacterial peptidoglycans, are associated with Crohn's disease. The underlying mechanism that results in increased inflammation in the guts of the patients bearing NOD2 mutations is still unclear. We

  4. Identification of a novel homozygous mutation in transmembrane channel like 1 (TMC1 gene, one of the second-tier hearing loss genes after GJB2 in India

    Directory of Open Access Journals (Sweden)

    Pawan Kumar Singh

    2017-01-01

    Interpretation & conclusions: While mutations in TMC1 are not as common a cause of NSHL as those in GJB2, TMC1 should be considered for diagnostic investigations in cases of NSHL in GJB2-negative families.

  5. Structural studies of p53 inactivation by DNA-contact mutations and its rescue by suppressor mutations via alternative protein–DNA interactions

    Science.gov (United States)

    Eldar, Amir; Rozenberg, Haim; Diskin-Posner, Yael; Rohs, Remo; Shakked, Zippora

    2013-01-01

    A p53 hot-spot mutation found frequently in human cancer is the replacement of R273 by histidine or cysteine residues resulting in p53 loss of function as a tumor suppressor. These mutants can be reactivated by the incorporation of second-site suppressor mutations. Here, we present high-resolution crystal structures of the p53 core domains of the cancer-related proteins, the rescued proteins and their complexes with DNA. The structures show that inactivation of p53 results from the incapacity of the mutated residues to form stabilizing interactions with the DNA backbone, and that reactivation is achieved through alternative interactions formed by the suppressor mutations. Detailed structural and computational analysis demonstrates that the rescued p53 complexes are not fully restored in terms of DNA structure and its interface with p53. Contrary to our previously studied wild-type (wt) p53-DNA complexes showing non-canonical Hoogsteen A/T base pairs of the DNA helix that lead to local minor-groove narrowing and enhanced electrostatic interactions with p53, the current structures display Watson–Crick base pairs associated with direct or water-mediated hydrogen bonds with p53 at the minor groove. These findings highlight the pivotal role played by R273 residues in supporting the unique geometry of the DNA target and its sequence-specific complex with p53. PMID:23863845

  6. Individuals who are homozygous for the 2282del4 and R501X filaggrin null mutations do not always develop dermatitis and complete long-term remission is possible.

    Science.gov (United States)

    Thyssen, J P; Carlsen, B C; Bisgaard, H; Giwercman, C; Johansen, J D; Linneberg, A; Meldgaard, M; Szecsi, P B; Stender, S; Menné, T

    2012-03-01

    About 8-10% of the general population in Europe carry a null mutation in the filaggrin gene which is associated with early onset of atopic dermatitis as well as persistence into adulthood. No studies have investigated whether individuals with the homozygous filaggrin null genotype always develop dermatitis. The aim of this study was to describe the natural history of individuals with no filaggrin expression. Three study populations were included: (i) a random sample of 3335 subjects aged 18-69 years from the general population in Copenhagen who underwent general health examination; (ii) a total of 499 patients seen in our dermatitis clinic since 2009 and who were filaggrin genotyped as a part of the routine diagnostic work up; and (iii) a prospective, longitudinal, birth cohort study of 411 children born to mothers with a history of asthma. Filaggrin genotyping was performed for the 2282del4 and R501X mutations. Filaggrin homozygous/compound heterozygous individuals accounted for 0.3% of adults, 3% of dermatitis patients and 0.7% of children. Respectively, one of nine adults and one of three children never experienced dermatitis until now. All hospital patients had atopic dermatitis with onset during (early) childhood. Year-long complete remission was observed in half of patients. The natural history of individuals with the filaggrin null genotype is fairly good in the sense that they may not develop dermatitis at all, and if they do, they may experience complete remission. © 2011 The Authors. Journal of the European Academy of Dermatology and Venereology © 2011 European Academy of Dermatology and Venereology.

  7. Novel homozygous mutations in the EVC and EVC2 genes in two consanguineous families segregating autosomal recessive Ellis-van Creveld syndrome.

    Science.gov (United States)

    Aziz, Abdul; Raza, Syed I; Ali, Salman; Ahmad, Wasim

    2016-01-01

    Ellis-van Creveld syndrome (EVC) is a rare developmental disorder characterized by short limbs, short ribs, postaxial polydactyly, dysplastic nails, teeth, oral and cardiac abnormalities. It is caused by biallelic mutations in the EVC or EVC2 gene, separated by 2.6 kb of genomic sequence on chromosome 4p16. In the present study, we have investigated two consanguineous families of Pakistani origin, segregating EVC in autosomal recessive manner. Linkage in the families was established to chromosome 4p16. Subsequently, sequence analysis identified a novel nonsense mutation (p.Trp234*) in exon 8 of the EVC2 gene and 15 bp duplication in exon 14 of the EVC gene in the two families. This further expands the mutations in the EVC or EVC2 genes resulting in the EVC syndrome.

  8. Generation of a human induced pluripotent stem cell line via CRISPR-Cas9 mediated integration of a site-specific homozygous mutation in CHMP2B

    DEFF Research Database (Denmark)

    Zhang, Yu; Schmid, Benjamin; Nielsen, Troels T

    2016-01-01

    Frontotemporal dementia (FTD) is an early onset neurodegenerative disease. Mutations in several genes cause familial FTD and one of them is charged multivesicular body protein 2B (CHMP2B) on chromosome 3 (FTD3), a component of the endosomal sorting complex required for transport III (ESCRT-III). We...... have generated an induced pluripotent stem cell (iPSC) line of a healthy individual and inserted the CHMP2B IVS5AS G-C gene mutation into both alleles, resulting in aberrant splicing. This human iPSC line provides an ideal model to study CHMP2B-dependent phenotypes of FTD3....

  9. Generation of a human induced pluripotent stem cell line via CRISPR-Cas9 mediated integration of a site-specific homozygous mutation in CHMP2B

    Directory of Open Access Journals (Sweden)

    Yu Zhang

    2016-07-01

    Full Text Available Frontotemporal dementia (FTD is an early onset neurodegenerative disease. Mutations in several genes cause familial FTD and one of them is charged multivesicular body protein 2B (CHMP2B on chromosome 3 (FTD3, a component of the endosomal sorting complex required for transport III (ESCRT-III. We have generated an induced pluripotent stem cell (iPSC line of a healthy individual and inserted the CHMP2B IVS5AS G-C gene mutation into both alleles, resulting in aberrant splicing. This human iPSC line provides an ideal model to study CHMP2B-dependent phenotypes of FTD3.

  10. Homozygous p.M172K mutation of the TFR2 gene in an Italian family with type 3 hereditary hemochromatosis and early onset iron overload.

    Science.gov (United States)

    Majore, S; Milano, F; Binni, F; Stuppia, L; Cerrone, A; Tafuri, A; De Bernardo, C; Palka, G; Grammatico, P

    2006-08-01

    The p.M172K TFR2 mutation was identified in two Italian siblings aged 32 and 40 years old with primary iron overload. The two patients showed a severe increase in serum iron indices. From the age of 25, the male sib also revealed abnormal levels of hepatic enzymes, presumably in relation to iron induced liver damage. Clinical findings seem to evidence that type 3 hemochromatosis can be more serious than classic hemochromatosis. This report adds two more type 3 hereditary hemochromatosis cases which suggest that TFR2 mutations could be more frequently involved in non-HFE hemochromatosis than has been actually thought.

  11. Impact of a novel homozygous mutation in nicotinamide nucleotide transhydrogenase on mitochondrial DNA integrity in a case of familial glucocorticoid deficiency

    Directory of Open Access Journals (Sweden)

    Yasuko Fujisawa

    2015-06-01

    General significance: By studying a family affected with a novel point mutation in the NNT gene, a gene–dose response was found for various mitochondrial outcomes providing for novel insights into the role of NNT in the maintenance of mtDNA integrity beyond that described for preventing oxidative stress.

  12. Generation of a human induced pluripotent stem cell line via CRISPR-Cas9 mediated integration of a site-specific homozygous mutation in CHMP2B

    DEFF Research Database (Denmark)

    Zhang, Yu; Schmid, Benjamin; Nielsen, Troels T.

    2016-01-01

    Frontotemporal dementia (FTD) is an early onset neurodegenerative disease. Mutations in several genes cause familial FTD and one of them is charged multivesicular body protein 2B (CHMP2B) on chromosome 3 (FTD3), a component of the endosomal sorting complex required for transport III (ESCRT-III). ...

  13. A New Mouse Model of Limb-Girdle Muscular Dystrophy Type 2I Homozygous for the Common L276I Mutation Mimicking the Mild Phenotype in Humans

    DEFF Research Database (Denmark)

    Krag, Thomas O; Vissing, John

    2015-01-01

    Limb-girdle muscular dystrophy type 2I (LGMD2I) is caused by mutations in the Fukutin-related protein (FKRP) gene, leading to inadequate glycosylation of α-dystroglycan, an important protein linking the extracellular matrix to the cytoskeleton. We created a mouse model of the common FKRP L276I...

  14. Coat's like vasculopathy in leber congenital amaurosis secondary to homozygous mutations in CRB1: a case report and discussion of the management options.

    Science.gov (United States)

    Hasan, Somar M; Azmeh, Arwa; Mostafa, Osama; Megarbane, Andre

    2016-02-13

    Mutations in the CRB1 gene are associated with variable phenotypes of severe retinal dystrophies, and retinal dystrophies resulting from CRB1 mutations may be accompanied by specific fundus features such as coat's like vasculopathy in retinitis pigmentosa patients. This is the first report of the occurrence of coat's like vasculopathy in a patient diagnosed with Leber congenital amaurosis caused by a CRB1 mutation. An 18-year old Syrian female patient presented with bilateral gradual loss of vision since early childhood, with recent deterioration in her left eye. She appeared to have an asymmetric bilateral coat's like vasculopathy which was more severe in the left eye. The diagnosis of Leber congenital amaurosis was suggested, and a genetic CRB1 sequencing for the patient and her two younger siblings, who also had severe vision loss, was done, upon which the diagnosis of Leber congenital amaurosis associated with exudative retinal detachment due to coat's like vasculopathy was made. Treatment with panretinal photocoagulation was attempted in the worse left eye, but with no improvement. As the disease suddenly progressed in both eyes, pars plana vitrectomy with endolaser and silicone oil tamponade was performed in the better right eye which led to anatomical stabilization of the case without improvement in the visual acuity. Leber congenital amaurosis is reported to be associated with multiple systemic and ocular findings, none of which is coat's like vasculopathy. CRB1 gene mutations are associated with remarkable retinal findings in patients with retinitis pigmentosa and other fundus dystrophies. In this unique case we are reporting the incidence of coat's like vasculopathy in a patient diagnosed with Leber congenital amaurosis caused by CRB1 gene mutation, and its management. CRB1 mutant patients should be followed up closely as sudden progression can have permanent poor outcomes and as early management is vital in such cases.

  15. Inactivating Mutation screening of Exon 6 and Exon 10E of FSHR gene in women with Polycystic Ovarian Syndrome in Vellore population

    Science.gov (United States)

    Sekar, Nishu; Sapre, Madhura; Kale, Vaikhari; Prabhu, Yogamaya D.; Renu, Kaviyarasi; Ramgir, Shalaka S.; Abilash, V. G.

    2017-11-01

    Polycystic Ovarian syndrome (PCOS) is a major cause of infertility in females of reproducing age and is typified by oligo-anovulation, hyperandrogenism, hirsutism and polycystic ovaries. FSHR gene located on chromosome 2 p21 is responsible for the normal follicular development and any deletion or mutation in the gene affects the interaction of FSH with its receptor. Thus, it becomes the candidate gene for PCOS study. Inactivating mutation in FSHR gene limits the receptor’s function by creating a complete block, changing the receptor-ligand complex or the basic hormone signal transduction.To screen the inactivating mutations in Exon 6 and Exon 10E of FSHR gene in women diagnosed with PCOS.PCR-RFLP analysis indicated that there were no inactivating mutations found in Exon 6 and Exon 10E. Variations in hormone levels were seen amongst the PCOS patients. There were no inactivating mutations found in FSHR gene of the women diagnosed with PCOS according to the Rotterdam criteria in Vellore population.

  16. Different inactivating mutations of the mineralocorticoid receptor in fourteen families affected by type I pseudohypoaldosteronism.

    Science.gov (United States)

    Sartorato, Paola; Lapeyraque, Anne-Laure; Armanini, Decio; Kuhnle, Ursula; Khaldi, Yasmina; Salomon, Rémi; Abadie, Véronique; Di Battista, Eliana; Naselli, Arturo; Racine, Alain; Bosio, Maurizio; Caprio, Massimiliano; Poulet-Young, Véronique; Chabrolle, Jean-Pierre; Niaudet, Patrick; De Gennes, Christiane; Lecornec, Marie-Hélène; Poisson, Elodie; Fusco, Anna Maria; Loli, Paola; Lombès, Marc; Zennaro, Maria-Christina

    2003-06-01

    We have analyzed the human mineralocorticoid receptor (hMR) gene in 14 families with autosomal dominant or sporadic pseudohypoaldosteronism (PHA1), a rare form of mineralocorticoid resistance characterized by neonatal renal salt wasting and failure to thrive. Six heterozygous mutations were detected. Two frameshift mutations in exon 2 (insT1354, del8bp537) and one nonsense mutation in exon 4 (C2157A, Cys645stop) generate truncated proteins due to premature stop codons. Three missense mutations (G633R, Q776R, L979P) differently affect hMR function. The DNA binding domain mutant R633 exhibits reduced maximal transactivation, although its binding characteristics and ED(50) of transactivation are comparable with wild-type hMR. Ligand binding domain mutants R776 and P979 present reduced or absent aldosterone binding, respectively, which is associated with reduced or absent ligand-dependent transactivation capacity. Finally, P979 possesses a transdominant negative effect on wild-type hMR activity, whereas mutations G633R and Q776R probably result in haploinsufficiency in PHA1 patients. We conclude that hMR mutations are a common feature of autosomal dominant PHA1, being found in 70% of our familial cases. Their absence in some families underscores the importance of an extensive investigation of the hMR gene and the role of precise diagnostic procedures to allow for identification of other genes potentially involved in the disease.

  17. To Screen Inactivation Mutation of Exon 1 of FSHR Gene in Polycystic Ovarian Syndrome: A South Indian Cohort Study

    Science.gov (United States)

    Sekar, Nishu; Yeole, Samiksha; Pradeep, Rashmi; Prabhu, Yogamaya D.; Renu, Kaviyarasi; Ramgir, Shalaka S.; Abilash, V. G.

    2017-11-01

    Polycystic ovary syndrome is an endocrine disorder. Irregular menstrual cycle, acne, facial hair and elevated androgen levels are the most common signs for PCOS. PCOS has an estimated prevalence of 4-12% among reproductive age women, thus making it a forerunner in female infertility. FSHR plays an important role in FSH signaling pathway making it an important gene for PCOS. In this study, we aim to focus on any association between the FSHR gene and PCOS. Our study was to evaluate any polymorphism of exon 1 of FSHR gene associated with PCOS.PCR-RFLP technique was performed on the PCOS samples. Hormonal changes were found in the patients. Exon 1 inactivation mutation of FSHR gene was not observed in the patient sample. A study of this association needs to be done using large sample size.

  18. Alcohol epitheliectomy with mechanical debridement in a case of granular corneal dystrophy with r555w homozygous mutation of TGF B1 gene

    Directory of Open Access Journals (Sweden)

    Garg Prashant

    2010-01-01

    Full Text Available An eight-year-old girl, an offspring of a consanguineous marriage presented with multiple anterior stromal geographic corneal opacities in both eyes. She was diagnosed to have superficial variant of granular dystrophy based on the family history, clinical features and mutation of TGF B1 gene. She was treated by alcohol-assisted removal of epithelium followed by mechanical debridement of abnormal deposits. Postoperatively, the cornea in both eyes was clear with no trace of opacity and the patient had an unaided visual acuity of 20/20 partial.

  19. Association of Exon 10A and 10B inactivating mutation of follicle stimulating hormone receptor gene (FSHR) and Polycystic Ovarian Syndrome in Vellore cohort

    Science.gov (United States)

    Sekar, Nishu; Kulkarni, Rucha; Ozalkar, Sharvari; Prabhu, Yogamaya D.; Renu, Kaviyarasi; Ramgir, Shalaka S.; Abilash, V. G.

    2017-11-01

    Polycystic ovarian syndrome is the most common heterogenous endocrine disorder in women. Follicle stimulating hormone receptor is associated with normal development as well as maturation of follicles and triggers estrogen production in granulosa cells of the ovary. Inactivating mutation in FSHR gene correlated with reduction of ovarian function in women is due to damage to receptor function. This study aims to investigate whether inactivating mutations, in follicle stimulating hormone receptor gene is related to polycystic ovarian morphology in women with PCOS. Genomic DNA isolated from 15 subjects from Sandhya Hospital, Vellore (10 patients with PCOS and 5 healthy controls) was taken for this study. Patient data included a clinical report, hormonal levels, and ovarian morphological details. DNA isolation was followed by DNA amplification by polymerase chain reaction using Exon 10 A and Exon 10 B primers. The PCR-RFLP analysis was performed using Dde1 restriction enzyme. Here we discuss inactivating mutation found in Exon 10 of FSHR gene in patients with PCOS.The absence of inactivating mutation was observed through PCR-RFLP study on Exon 10A and Exon 10B.

  20. Normalization of serum calcium by cinacalcet in a patient with hypercalcaemia due to a de novo inactivating mutation of the calcium-sensing receptor.

    NARCIS (Netherlands)

    Timmers, H.J.L.M.; Karperien, M.; Hamdy, N.A.; Boer, H. de; Hermus, A.R.M.M.

    2006-01-01

    Familial benign hypocalciuric hypercalcaemia (FHH) results from a heterozygous inactivating mutation of the calcium-sensing receptor (CaR) and is characterized by hypercalcaemia, hypocalciuria and inappropriately normal plasma levels of parathyroid hormone. In a minority of patients, a loss of

  1. Truncating Homozygous Mutation of Carboxypeptidase E (CPE in a Morbidly Obese Female with Type 2 Diabetes Mellitus, Intellectual Disability and Hypogonadotrophic Hypogonadism.

    Directory of Open Access Journals (Sweden)

    Suzanne I M Alsters

    Full Text Available Carboxypeptidase E is a peptide processing enzyme, involved in cleaving numerous peptide precursors, including neuropeptides and hormones involved in appetite control and glucose metabolism. Exome sequencing of a morbidly obese female from a consanguineous family revealed homozygosity for a truncating mutation of the CPE gene (c.76_98del; p.E26RfsX68. Analysis detected no CPE expression in whole blood-derived RNA from the proband, consistent with nonsense-mediated decay. The morbid obesity, intellectual disability, abnormal glucose homeostasis and hypogonadotrophic hypogonadism seen in this individual recapitulates phenotypes in the previously described fat/fat and Cpe knockout mouse models, evidencing the importance of this peptide/hormone-processing enzyme in regulating body weight, metabolism, and brain and reproductive function in humans.

  2. A complement C5 gene mutation, c.754G>A:p.A252T, is common in the Western Cape, South Africa and found to be homozygous in seven percent of Black African meningococcal disease cases.

    Science.gov (United States)

    Owen, E Patricia; Würzner, Reinhard; Leisegang, Felicity; Rizkallah, Pierre; Whitelaw, Andrew; Simpson, John; Thomas, Andrew D; Harris, Claire L; Giles, Joanna L; Hellerud, Bernt C; Mollnes, Tom E; Morgan, B Paul; Potter, Paul C; Orren, Ann

    2015-03-01

    Patients with genetically determined deficiency of complement component 5 are usually diagnosed because of recurrent invasive Neisseria meningitidis infections. Approximately 40 individual cases have been diagnosed worldwide. Nevertheless, reports of the responsible genetic defects have been sporadic, and we know of no previous reports of C5 deficiency being associated with a number of independent meningococcal disease cases in particular communities. Here we describe C5 deficiency in seven unrelated Western Cape, South African families. Three different C5 mutations c.55C>T:p.Q19X, c.754G>A:p.A252T and c.4426C>T:p.R1476X were diagnosed in index cases from two families who had both presented with recurrent meningococcal disease. p.Q19X and p.R1476X have already been described in North American Black families and more recently p.Q19X in a Saudi family. However, p.A252T was only reported in SNP databases and was not associated with disease until the present study was undertaken in the Western Cape, South Africa. We tested for p.A252T in 140 patients presenting with meningococcal disease in the Cape Town area, and found seven individuals in five families who were homozygous for the mutation p.A252T. Very low serum C5 protein levels (0.1-4%) and correspondingly low in vitro functional activity were found in all homozygous individuals. Allele frequencies of p.A252T in the Black African and Cape Coloured communities were 3% and 0.66% and estimated homozygosities are 1/1100 and 1/22,500 respectively. In 2012 we reported association between p.A252T and meningococcal disease. Molecular modelling of p.A252T has indicated an area of molecular stress in the C5 molecule which may provide a mechanism for the very low level in the circulation. This report includes seven affected families indicating that C5D is not rare in South Africa. Copyright © 2014 The Authors. Published by Elsevier Ltd.. All rights reserved.

  3. Mutation in the protease cleavage site of GDF9 increases ovulation rate and litter size in heterozygous ewes and causes infertility in homozygous ewes.

    Science.gov (United States)

    Souza, C J H; McNeilly, A S; Benavides, M V; Melo, E O; Moraes, J C F

    2014-10-01

    Litter size (LS) in sheep is determined mainly by ovulation rate (OR). Several polymorphisms have been identified in the growth differentiation factor 9 (GDF9) gene that result in an increase in OR and prolificacy of sheep. Screening the databank of the Brazilian Sheep Breeders Association for triplet delivery, we identified flocks of prolific Ile de France ewes. After resequencing of GDF9, a point mutation (c.943C>T) was identified, resulting in a non-conservative amino acid change (p.Arg315Cys) in the cleavage site of the propeptide. This new allele was called Vacaria (FecG(v) ). A flock of half-sib ewes was evaluated for OR in the first three breeding seasons, and Vacaria heterozygotes had higher OR (P < 0.001), averaging 2.1 ± 0.1 when compared to 1.2 ± 0.1 in wild-type ewes. The OR was also influenced by age, increasing in the second and third breeding seasons (P < 0.001). In flocks segregating this allele, the LS was higher in mutant sheep (P < 0.001), averaging 1.61 ± 0.07 in heterozygotes and 1.29 ± 0.03 in wild-type ewes. Analysis of homozygote reproductive tract morphology revealed uterine and ovarian hypoplasia. Ovarian follicles continue to develop up to small antral stages, although with abnormal oocyte morphology and altered arrangement of granulosa cells. After the collapse of the oocyte in most follicles, the remaining cells formed clusters that persisted in the ovary. This SNP is useful to improve selection for dam prolificacy and also as a model to investigate GDF9 post-translation processing and the fate of the follicular cells that remain after the oocyte demise. © 2014 Stichting International Foundation for Animal Genetics.

  4. An inactivating mutation in the SOD 1 gene causes familial amyotrophic lateral sclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Pramatarova, A.; Rouleau, G.A. [Montreal General Hospital Research Institute (Canada); Goto, J. [Univ. of Tokyo (Japan)] [and others

    1994-09-01

    Amyotrophic lateral sclerosis (ALS) is characterized by highly selective death of large motor neurons in the cerebral cortex and spinal cord. The familial form of ALS (FALS) accounts for approximately 10% of the cases and is transmitted in an autosomal dominant manner. Recently the defective gene causing chromosome 21-linked FALS was shown to be the Cu/Zn superoxide dismutase (SOD 1). However, the precise mechanism of neurotoxicity seen in FALS with SOD 1 mutations is still unknown. Until now all SOD 1 mutations reported were single base pair substitutions (missense). We have identified a nonsense mutation in exon 5 of the SOD 1 gene in a FALS kindred. This two base pair deletion provokes a frameshift and a predicted premature truncation of the protein. The region affected has a very important structural and functional role: it contains part of the active loop and is involved in dimer contact. We would predict that the loss of these structures would impair the functioning of the enzyme.

  5. Pulmonary artery pressure and iron deficiency in patients with upregulation of hypoxia sensing due to homozygous VHLR200W mutation (Chuvash polycythemia)

    Science.gov (United States)

    Sable, Craig A.; Aliyu, Zakari Y.; Dham, Niti; Nouraie, Mehdi; Sachdev, Vandana; Sidenko, Stanislav; Miasnikova, Galina Y.; Polyakova, Lydia A.; Sergueeva, Adelina I.; Okhotin, Daniel J.; Bushuev, Vladimir; Remaley, Alan T.; Niu, Xiaomei; Castro, Oswaldo L.; Gladwin, Mark T.; Kato, Gregory J.; Prchal, Josef T.; Gordeuk, Victor R.

    2012-01-01

    Background Patients with Chuvash polycythemia, (homozygosity for the R200W mutation in the von Hippel Lindau gene (VHL)), have elevated levels of hypoxia inducible factors HIF-1 and HIF-2, often become iron-deficient secondary to phlebotomy, and have elevated estimated pulmonary artery pressure by echocardiography. The objectives of this study were to provide a comprehensive echocardiographic assessment of cardiovascular physiology and to identify clinical, hematologic and cardiovascular risk factors for elevation of tricuspid regurgitation velocity in children and adults with Chuvash polycythemia. Design and Methods This cross-sectional observational study of 120 adult and pediatric VHLR200W homozygotes and 31 controls at outpatient facilities in Chuvashia, Russian Federation included echocardiography assessment of pulmonary artery pressure (tricuspid regurgitation velocity), cardiac volume, and systolic and diastolic function, as well as hematologic and clinical parameters. We determined the prevalence and risk factors for elevation of tricuspid regurgitation velocity in this population and its relationship to phlebotomy. Results The age-adjusted mean ± SE tricuspid regurgitation velocity was higher in VHLR200W homozygotes than controls with normal VHL alleles (2.5±0.03 vs. 2.3±0.05 m/sec, P=0.005). The age-adjusted left ventricular diastolic diameter (4.8±0.05 vs. 4.5±0.09 cm, P=0.005) and left atrial diameter (3.4±0.04 vs. 3.2±0.08 cm, P=0.011) were also greater in the VHLR200W homozygotes, consistent with increased blood volume, but the elevation in tricuspid regurgitation velocity persisted after adjustment for these variables. Among VHLR200W homozygotes, phlebotomy therapy was associated with lower serum ferritin concentration, and low ferritin independently predicted higher tricuspid regurgitation velocity (standardized beta=0.29; P=0.009). Conclusions Children and adults with Chuvash polycythemia have higher estimated right ventricular systolic

  6. Pulmonary artery pressure and iron deficiency in patients with upregulation of hypoxia sensing due to homozygous VHL(R200W) mutation (Chuvash polycythemia).

    Science.gov (United States)

    Sable, Craig A; Aliyu, Zakari Y; Dham, Niti; Nouraie, Mehdi; Sachdev, Vandana; Sidenko, Stanislav; Miasnikova, Galina Y; Polyakova, Lydia A; Sergueeva, Adelina I; Okhotin, Daniel J; Bushuev, Vladimir; Remaley, Alan T; Niu, Xiaomei; Castro, Oswaldo L; Gladwin, Mark T; Kato, Gregory J; Prchal, Josef T; Gordeuk, Victor R

    2012-02-01

    Patients with Chuvash polycythemia, (homozygosity for the R200W mutation in the von Hippel Lindau gene (VHL)), have elevated levels of hypoxia inducible factors HIF-1 and HIF-2, often become iron-deficient secondary to phlebotomy, and have elevated estimated pulmonary artery pressure by echocardiography. The objectives of this study were to provide a comprehensive echocardiographic assessment of cardiovascular physiology and to identify clinical, hematologic and cardiovascular risk factors for elevation of tricuspid regurgitation velocity in children and adults with Chuvash polycythemia. This cross-sectional observational study of 120 adult and pediatric VHL(R200W) homozygotes and 31 controls at outpatient facilities in Chuvashia, Russian Federation included echocardiography assessment of pulmonary artery pressure (tricuspid regurgitation velocity), cardiac volume, and systolic and diastolic function, as well as hematologic and clinical parameters. We determined the prevalence and risk factors for elevation of tricuspid regurgitation velocity in this population and its relationship to phlebotomy. The age-adjusted mean ± SE tricuspid regurgitation velocity was higher in VHL(R200W) homozygotes than controls with normal VHL alleles (2.5±0.03 vs. 2.3±0.05 m/sec, P=0.005). The age-adjusted left ventricular diastolic diameter (4.8±0.05 vs. 4.5±0.09 cm, P=0.005) and left atrial diameter (3.4±0.04 vs. 3.2±0.08 cm, P=0.011) were also greater in the VHL(R200W) homozygotes, consistent with increased blood volume, but the elevation in tricuspid regurgitation velocity persisted after adjustment for these variables. Among VHL(R200W) homozygotes, phlebotomy therapy was associated with lower serum ferritin concentration, and low ferritin independently predicted higher tricuspid regurgitation velocity (standardized beta=0.29; P=0.009). Children and adults with Chuvash polycythemia have higher estimated right ventricular systolic pressure, even after adjustment for

  7. Thirty-Eight-Year Follow-Up of Two Sibling Lipoid Congenital Adrenal Hyperplasia Patients Due to Homozygous Steroidogenic Acute Regulatory (STARD1) Protein Mutation. Molecular Structure and Modeling of the STARD1 L275P Mutation

    Science.gov (United States)

    Khoury, Khalil; Barbar, Elie; Ainmelk, Youssef; Ouellet, Annie; Lavigne, Pierre; LeHoux, Jean-Guy

    2016-01-01

    Objective: Review the impact of StAR (STARD1) mutations on steroidogenesis and fertility in LCAH patients. Examine the endocrine mechanisms underlying the pathology of the disorder and the appropriate therapy for promoting fertility and pregnancies. Design: Published data in the literature and a detailed 38-year follow-up of two sibling LCAH patients. Molecular structure and modeling of the STARD1 L275P mutation. Setting: University hospital. Patients: Patient A (46,XY female phenotype) and patient B (46,XX female) with LCAH bearing the L275P mutation in STARD1. Interventions: Since early-age diagnosis, both patients underwent corticoid replacement therapy. Patient A received estrogen therapy at pubertal age. Clomiphene therapy was given to Patient B to induce ovulation. Pregnancies were protected with progesterone administration. Main Outcome Measures: Clinical and molecular assessment of adrenal and gonadal functions. Results: Both patients have classic manifestations of corticosteroid deficiency observed in LCAH. Time of onset and severity were different. Patient A developed into a female phenotype due to early and severe damage of Leydig cells. Patient B started a progressive pubertal development, menarche and regular non-ovulatory cycle. She was able to have successful pregnancies. Conclusions: Understanding the molecular structure and function of STARD1 in all steroidogenic tissues is the key for comprehending the heterogeneous clinical manifestations of LCAH, and the development of an appropriate strategy for the induction of ovulation and protecting pregnancies in this disease. PMID:27917104

  8. Systematic production of inactivating and non-inactivating suppressor mutations at the relA locus that compensate the detrimental effects of complete spot loss and affect glycogen content in Escherichia coli.

    Directory of Open Access Journals (Sweden)

    Manuel Montero

    Full Text Available In Escherichia coli, ppGpp is a major determinant of growth and glycogen accumulation. Levels of this signaling nucleotide are controlled by the balanced activities of the ppGpp RelA synthetase and the dual-function hydrolase/synthetase SpoT. Here we report the construction of spoT null (ΔspoT mutants obtained by transducing a ΔspoT allele from ΔrelAΔspoT double mutants into relA+ cells. Iodine staining of randomly selected transductants cultured on a rich complex medium revealed differences in glycogen content among them. Sequence and biochemical analyses of 8 ΔspoT clones displaying glycogen-deficient phenotypes revealed different inactivating mutations in relA and no detectable ppGpp when cells were cultured on a rich complex medium. Remarkably, although the co-existence of ΔspoT with relA proficient alleles has generally been considered synthetically lethal, we found that 11 ΔspoT clones displaying high glycogen phenotypes possessed relA mutant alleles with non-inactivating mutations that encoded stable RelA proteins and ppGpp contents reaching 45-85% of those of wild type cells. None of the ΔspoT clones, however, could grow on M9-glucose minimal medium. Both Sanger sequencing of specific genes and high-throughput genome sequencing of the ΔspoT clones revealed that suppressor mutations were restricted to the relA locus. The overall results (a defined in around 4 nmoles ppGpp/g dry weight the threshold cellular levels that suffice to trigger net glycogen accumulation, (b showed that mutations in relA, but not necessarily inactivating mutations, can be selected to compensate total SpoT function(s loss, and (c provided useful tools for studies of the in vivo regulation of E. coli RelA ppGpp synthetase.

  9. Assessment of safety and efficacy of long-term treatment with combination lumacaftor and ivacaftor therapy in patients with cystic fibrosis homozygous for the F508del-CFTR mutation (PROGRESS): a phase 3, extension study.

    Science.gov (United States)

    Konstan, Michael W; McKone, Edward F; Moss, Richard B; Marigowda, Gautham; Tian, Simon; Waltz, David; Huang, Xiaohong; Lubarsky, Barry; Rubin, Jaime; Millar, Stefanie J; Pasta, David J; Mayer-Hamblett, Nicole; Goss, Christopher H; Morgan, Wayne; Sawicki, Gregory S

    2017-02-01

    The 24-week safety and efficacy of lumacaftor/ivacaftor combination therapy was shown in two randomised controlled trials (RCTs)-TRAFFIC and TRANSPORT-in patients with cystic fibrosis who were aged 12 years or older and homozygous for the F508del-CFTR mutation. We aimed to assess the long-term safety and efficacy of extended lumacaftor/ivacaftor therapy in this group of patients in PROGRESS, the long-term extension of TRAFFIC and TRANSPORT. PROGRESS was a phase 3, parallel-group, multicentre, 96-week study of patients who completed TRAFFIC or TRANSPORT in 191 sites in 15 countries. Patients were eligible if they were at least 12 years old with cystic fibrosis and homozygous for the F508del-CFTR mutation. Exclusion criteria included any comorbidity or laboratory abnormality that, in the opinion of the investigator, might confound the results of the study or pose an additional risk in administering the study drug to the participant, history of drug intolerance, and history of poor compliance with the study drug. Patients who previously received active treatment in TRANSPORT or TRAFFIC remained on the same dose in PROGRESS. Patients who had received placebo in TRANSPORT or TRAFFIC were randomly assigned (1:1) to receive lumacaftor (400 mg every 12 h)/ivacaftor (250 mg every 12 h) or lumacaftor (600 mg once daily)/ivacaftor (250 mg every 12 h). The primary outcome was to assess the long-term safety of combined therapy. The estimated annual rate of decline in percent predicted FEV1 (ppFEV1) in treated patients was compared with that of a matched registry cohort. Efficacy analyses were based on modified intention-to-treat, such that data were included for all patients who were randomly assigned and received at least one dose of study drug. This study is registered with ClinicalTrials.gov, number NCT01931839. Between Oct 24, 2013, and April 7, 2016, 1030 patients from the TRANSPORT and TRAFFIC studies enrolled in PROGRESS, and 1029 received at least one dose of study drug

  10. Mitotic recombination and compound-heterozygous mutations are predominant NF1-inactivating mechanisms in children with juvenile myelomonocytic leukemia and neurofibromatosis type 1

    Science.gov (United States)

    Steinemann, Doris; Arning, Larissa; Praulich, Inka; Stuhrmann, Manfred; Hasle, Henrik; Starý, Jan; Schlegelberger, Brigitte; Niemeyer, Charlotte M.; Flotho, Christian

    2010-01-01

    Children with neurofibromatosis type 1 (NF-1), being constitutionally deficient for one allele of the NF1 gene, are at greatly increased risk of juvenile myelomonocytic leukemia (JMML). NF1 is a negative regulator of RAS pathway activity, which has a central role in JMML. To further clarify the role of biallelic NF1 gene inactivation in the pathogenesis of JMML, we investigated the somatic NF1 lesion in 10 samples from children with JMML/NF-1. We report that two-thirds of somatic events involved loss of heterozygosity (LOH) at the NF1 locus, predominantly caused by segmental uniparental disomy of large parts of chromosome arm 17q. One-third of leukemias showed compound-heterozygous NF1-inactivating mutations. A minority of cases exhibited somatic interstitial deletions. The findings reinforce the emerging role of somatic mitotic recombination as a leukemogenic mechanism. In addition, they support the concept that biallelic NF1 inactivation in hematopoietic progenitor cells is required for transformation to JMML in children with NF-1. PMID:20015894

  11. Gasdermin C Is Upregulated by Inactivation of Transforming Growth Factor β Receptor Type II in the Presence of Mutated Apc, Promoting Colorectal Cancer Proliferation.

    Directory of Open Access Journals (Sweden)

    Masashi Miguchi

    Full Text Available Mutations in TGFBR2, a component of the transforming growth factor (TGF-β signaling pathway, occur in high-frequency microsatellite instability (MSI-H colorectal cancer (CRC. In mouse models, Tgfbr2 inactivation in the intestinal epithelium accelerates the development of malignant intestinal tumors in combination with disruption of the Wnt-β-catenin pathway. However, no studies have further identified the genes influenced by TGFBR2 inactivation following disruption of the Wnt-β-catenin pathway. We previously described CDX2P-G19Cre;Apcflox/flox mice, which is stochastically null for Apc in the colon epithelium. In this study, we generated CDX2P-G19Cre;Apcflox/flox;Tgfbr2flox/flox mice, with simultaneous loss of Apc and Tgfbr2. These mice developed tumors, including adenocarcinoma in the proximal colon. We compared gene expression profiles between tumors of the two types of mice using microarray analysis. Our results showed that the expression of the murine homolog of GSDMC was significantly upregulated by 9.25-fold in tumors of CDX2P-G19Cre;Apcflox/flox;Tgfbr2flox/flox mice compared with those of CDX2P-G19Cre;Apcflox/flox mice. We then investigated the role of GSDMC in regulating CRC tumorigenesis. The silencing of GSDMC led to a significant reduction in the proliferation and tumorigenesis of CRC cell lines, whereas the overexpression of GSDMC enhanced cell proliferation. These results suggested that GSDMC functioned as an oncogene, promoting cell proliferation in colorectal carcinogenesis. In conclusion, combined inactivation of both Apc and Tgfbr2 in the colon epithelium of a CRC mouse model promoted development of adenocarcinoma in the proximal colon. Moreover, GSDMC was upregulated by TGFBR2 mutation in CRC and promoted tumor cell proliferation in CRC carcinogenesis, suggesting that GSDMC may be a promising therapeutic target.

  12. A Catalog of Genes Homozygously Deleted in Human Lung Cancer and the Candidacy of PTPRD as a Tumor Suppressor Gene

    Science.gov (United States)

    Kohno, Takashi; Otsuka, Ayaka; Girard, Luc; Sato, Masanori; Iwakawa, Reika; Ogiwara, Hideaki; Sanchez-Cespedes, Montse; Minna, John D.; Yokota, Jun

    2010-01-01

    A total of 176 genes homozygously deleted in human lung cancer were identified by DNA array-based whole genome scanning of 52 lung cancer cell lines and subsequent genomic PCR in 74 cell lines, including the 52 cell lines scanned. One or more exons of these genes were homozygously deleted in one (1%) to 20 (27%) cell lines. These genes included known tumor suppressor genes, e.g., CDKN2A/p16, RB1, and SMAD4, and candidate tumor suppressor genes whose hemizygous or homozygous deletions were reported in several types of human cancers, such as FHIT, KEAP1, and LRP1B/LRP-DIP. CDKN2A/p16 and p14ARF located in 9p21 were most frequently deleted (20/74, 27%). The PTPRD gene was most frequently deleted (8/74, 11%) among genes mapping to regions other than 9p21. Somatic mutations, including a nonsense mutation, of the PTPRD gene were detected in 8/74 (11%) of cell lines and 4/95 (4%) of surgical specimens of lung cancer. Reduced PTPRD expression was observed in the majority (>80%) of cell lines and surgical specimens of lung cancer. Therefore, PTPRD is a candidate tumor suppressor gene in lung cancer. Microarray-based expression profiling of 19 lung cancer cell lines also indicated that some of the 176 genes, such as KANK and ADAMTS1, are preferentially inactivated by epigenetic alterations. Genetic/epigenetic as well as functional studies of these 176 genes will increase our understanding of molecular mechanisms behind lung carcinogenesis. PMID:20073072

  13. Contraception-related deep venous thrombosis and pulmonary embolism in a 17-Year-old girl heterozygous for factor V leiden, prothrombin G20210A mutation, MTHFR C677T and homozygous for PAI-1 mutation: report of a family with multiple genetic risk factors and review of the literature.

    Science.gov (United States)

    Lenicek Krleza, Jasna; Jakovljevic, Gordana; Bronic, Ana; Coen Herak, Désirée; Bonevski, Aleksandra; Stepan-Giljevic, Jasminka; Roic, Goran

    2010-01-01

    We present the case of a 17-year-old girl who suddenly woke up with localized pain in the left groin and the inability to twist her leg. After comprehensive physician and laboratory examinations, deep venous thrombosis with consequent pulmonary embolism was ascertained. She had not experienced any recent trauma, but she had started to take oral contraceptives 6 months prior to the onset of the symptoms. Her parents and sisters had been asymptomatic throughout their lives, but the family history revealed a few thromboembolic accidents. Using DNA analysis, heterozygosity for factor V Leiden, prothrombin gene mutation G20210A and methylenetetrahydrofolate reductase C677T, as well as the homozygous 4G/4G genotype in the plasminogen activator inhibitor 1 were identified in our patient. Subsequently, DNA analysis was performed in all living family members, and multiple factors associated with thrombophilia were discovered. Our case confirms the multifactorial cause of thromboembolic events and emphasizes the importance of oral contraceptive use in the onset of venous thrombosis, especially in teenage females. In addition, this case indicates that teenage females with a family history of thrombosis who are making choices about contraception could most likely benefit from advanced thrombophilia testing. Copyright © 2010 S. Karger AG, Basel.

  14. The Domain II S4-S5 Linker in Nav1.9: A Missense Mutation Enhances Activation, Impairs Fast Inactivation, and Produces Human Painful Neuropathy.

    Science.gov (United States)

    Han, Chongyang; Yang, Yang; de Greef, Bianca T A; Hoeijmakers, Janneke G J; Gerrits, Monique M; Verhamme, Camiel; Qu, Jian; Lauria, Giuseppe; Merkies, Ingemar S J; Faber, Catharina G; Dib-Hajj, Sulayman D; Waxman, Stephen G

    2015-06-01

    Painful small fiber neuropathy is a challenging medical condition with no effective treatment. Non-genetic causes can be identified in one half of the subjects. Gain-of-function variants of sodium channels Nav1.7 and Nav1.8 have recently been associated with painful small fiber neuropathy. More recently, mutations of sodium channel Nav1.9 have been linked to human pain disorders, with two gain-of-function mutations found in patients with painful small fiber neuropathy. Here we report a novel Nav1.9 mutation, a glycine 699 substitution by arginine (G699R) in the domain II S4-S5 linker, identified in a patient with painful small fiber neuropathy. In this study, we assayed the mutant channels by voltage-clamp in superior cervical ganglion neurons, which do not produce endogenous Nav1.8 or Nav1.9 currents, and provide a novel platform where Nav1.9 is expressed at relatively high levels. Voltage-clamp analysis showed that the mutation hyperpolarizes (-10.1 mV) channel activation, depolarizes (+6.3 mV) steady-state fast inactivation, slows deactivation, and enhances ramp responses compared with wild-type Nav1.9 channels. Current-clamp analysis showed that the G699R mutant channels render dorsal root ganglion neurons hyperexcitable, via depolarized resting membrane potential, reduced current threshold and increased evoked firing. These observations show that the domain II S4-S5 linker plays an important role in the gating of Nav1.9 and demonstrates that a mutation in this linker is linked to a common pain disorder.

  15. Homozygous loss-of-function variants in European cosmopolitan and isolate populations.

    Science.gov (United States)

    Kaiser, Vera B; Svinti, Victoria; Prendergast, James G; Chau, You-Ying; Campbell, Archie; Patarcic, Inga; Barroso, Inês; Joshi, Peter K; Hastie, Nicholas D; Miljkovic, Ana; Taylor, Martin S; Enroth, Stefan; Memari, Yasin; Kolb-Kokocinski, Anja; Wright, Alan F; Gyllensten, Ulf; Durbin, Richard; Rudan, Igor; Campbell, Harry; Polašek, Ozren; Johansson, Åsa; Sauer, Sascha; Porteous, David J; Fraser, Ross M; Drake, Camilla; Vitart, Veronique; Hayward, Caroline; Semple, Colin A; Wilson, James F

    2015-10-01

    Homozygous loss of function (HLOF) variants provide a valuable window on gene function in humans, as well as an inventory of the human genes that are not essential for survival and reproduction. All humans carry at least a few HLOF variants, but the exact number of inactivated genes that can be tolerated is currently unknown—as are the phenotypic effects of losing function for most human genes. Here, we make use of 1432 whole exome sequences from five European populations to expand the catalogue of known human HLOF mutations; after stringent filtering of variants in our dataset, we identify a total of 173 HLOF mutations, 76 (44%) of which have not been observed previously. We find that population isolates are particularly well suited to surveys of novel HLOF genes because individuals in such populations carry extensive runs of homozygosity, which we show are enriched for novel, rare HLOF variants. Further, we make use of extensive phenotypic data to show that most HLOFs, ascertained in population-based samples, appear to have little detectable effect on the phenotype. On the contrary, we document several genes directly implicated in disease that seem to tolerate HLOF variants. Overall HLOF genes are enriched for olfactory receptor function and are expressed in testes more often than expected, consistent with reduced purifying selection and incipient pseudogenisation. © The Author 2015. Published by Oxford University Press.

  16. Prenatal diagnosis and molecular genetic analysis of short rib-polydactyly syndrome type III (Verma-Naumoff in a second-trimester fetus with a homozygous splice site mutation in intron 4 in the NEK1 gene

    Directory of Open Access Journals (Sweden)

    Chih-Ping Chen

    2012-06-01

    Conclusion: Polydactyly, micromelia, metaphyseal spurs, widened humeral metaphyses, and shortened ribs can be prominent prenatal ultrasound findings of SRPS III. The present case provides evidence for a correlation of a mutation in the NEK1 gene with SRPS III.

  17. Antibiotic resistance in Pseudomonas aeruginosa strains with increased mutation frequency due to inactivation of the DNA oxidative repair system

    DEFF Research Database (Denmark)

    Mandsberg, Lotte F; Ciofu, Oana; Kirkby, N

    2009-01-01

    in resistant HP clinical isolates from patients with CF, and complementation with wild-type genes reverted the phenotype. In conclusion, oxidative stress might be involved in the development of resistance to antibiotics. We therefore suggest the possible use of antioxidants for CF patients to prevent...... (hypermutators [HP]). P. aeruginosa is exposed to oxygen radicals, both those generated by its own metabolism and especially those released by a large number of PMNs in response to the chronic CF lung infection. Our work therefore focused on the role of the DNA oxidative repair system in the development of HP...... and antibiotic resistance. We have constructed and characterized mutT, mutY, and mutM mutants in P. aeruginosa strain PAO1. The mutT and mutY mutants showed 28- and 7.5-fold increases in mutation frequencies, respectively, over that for PAO1. These mutators had more oxidative DNA damage (higher levels of 7...

  18. Homozygous antithrombin deficiency type II causing neonatal thrombosis.

    Science.gov (United States)

    Swoboda, Vanessa; Zervan, Katharina; Thom, Katharina; Mannhalter, Christine; Quehenberger, Peter; Pabinger, Ingrid; Male, Christoph

    2017-09-04

    We report four children from different families with homozygous antithrombin (AT) deficiency type II affecting the heparin binding site (p.Leu131Phe mutation). All children had severe spontaneous venous and/or arterial thromboembolic events shortly after birth. This report intends to raise awareness among clinicians about this rare but severe condition. When thrombosis occurs in an otherwise healthy newborn, a severe congenital thrombophilic disorder should be considered. In homozygous AT deficiency type II, AT activity is typically reduced but may also be in the normal range, posing a diagnostic challenge. Rapid diagnosis is important to initiate appropriate therapy. Standard anticoagulation with heparin may prove ineffective in severe AT deficiency, requiring substitution of AT concentrate and early switch to alternative anticoagulants such as vitamin K antagonists. Copyright © 2017. Published by Elsevier Ltd.

  19. Homozygous partial genomic triplication of the parkin gene in early-onset parkinsonism.

    Science.gov (United States)

    Mata, Ignacio F; Alvarez, Victoria; Coto, Eliecer; Blazquez, Marta; Guisasola, Luis M; Salvador, Carlos; Kachergus, Jennifer M; Lincoln, Sarah J; Farrer, Matthew

    2005-06-03

    Autosomal recessive mutations in the parkin gene are the predominant cause of familial, early-onset parkinsonism; missense mutations involving one or a few nucleotides, exonic deletions and duplications have been described. Here we report a family with two affected brothers. Direct sequencing of parkin did not detect mutations, but semi-quantitative analysis identified a novel exonic rearrangement of exons 2-4. Both patients were homozygous for unique genomic triplications of the parkin gene.

  20. Development of antibiotic resistance and up-regulation of the antimutator gene pfpI in mutator Pseudomonas aeruginosa due to inactivation of two DNA oxidative repair genes (mutY, mutM)

    DEFF Research Database (Denmark)

    Mandsberg, Lotte Frigaard; Macia, Maria D.; Bergmann, Kirsten R.

    2011-01-01

    Prevention and correction of oxidative DNA lesions in Pseudomonas aeruginosa is ensured by the DNA oxidative repair system (GO). Single inactivation of mutT, mutY and mutM involved in GO led to elevated mutation rates (MRs) that correlated to increased development of resistance to antibiotics...... showed only a fivefold increase, whereas the single mutant PAOMMgm (mutM) showed a nonsignificant increase in MR compared with PAO1 and the single mutants. Mutations in the regulator nfxB leading to hyperexpression of MexCD-OprJ efflux pump were found as the mechanism of resistance to ciprofloxacin...... in the double mutant. A better fitness of the mutator compared with PAO1 was found in growth competition experiments in the presence of ciprofloxacin at concentrations just below minimal inhibitory concentration. Up-regulation of the antimutator gene pfpI, that has been shown to provide protection to oxidative...

  1. X-inactivation pattern in multiple tissues from two Leber's hereditary optic neuropathy (LHON) patients.

    Science.gov (United States)

    Pegoraro, Elena; Vettori, Andrea; Valentino, Maria L; Molon, Annamaria; Mostacciuolo, Maria L; Howell, Neil; Carelli, Valerio

    2003-05-15

    The more frequent manifestation of ophthalmological abnormalities in males, relative to females, is an unexplained feature of Leber's hereditary optic neuropathy (LHON) that suggests an X-linked modifying gene acting in concert with the pathogenic LHON mitochondrial DNA (mtDNA) mutation. In addition, segregation analysis of the optic neuropathy in LHON pedigrees was compatible with the presence of a recessive-modifying gene on chromosome X. According to this two-locus model, females would be affected only if homozygous or if they were susceptible to skewed X-inactivation. Attempts both to localize the putative LHON-modifying gene by linkage analysis and to find an excess of skewed X-inactivation in affected females were unsuccessful, although the inactivation pattern was only studied in DNA isolated from blood cells. We had the opportunity to analyze a wide range of tissues at autopsy, including the optic nerves and the retina, from two LHON female patients. We found no evidence of skewed X-inactivation in the affected tissues, thus weakening further the hypothesized involvement of a specific X chromosome locus in the pathophysiological expression of LHON. Copyright 2003 Wiley-Liss, Inc.

  2. Abnormal activation and inactivation mechanisms of rod transduction in patients with autosomal dominant retinitis pigmentosa and the pro-23-his mutation.

    Science.gov (United States)

    Birch, D G; Hood, D C; Nusinowitz, S; Pepperberg, D R

    1995-07-01

    The leading edge of the rod a-wave in normal human subjects can be fit with a computational model of the activation phase of transduction to provide parameters analogous to those obtained from individual photoreceptors. The authors extend this work to the kinetics of recovery after saturating flashes. Electroretinograms were recorded from three patients with autosomal dominant retinitis pigmentosa and the pro-23-his rhodopsin mutation, two patients with rod monochromatism, and five normal subjects. Rod-only a-waves were obtained for a series of flashes ranging from 4.4 to 10.1 ln (1.9 to 4.4 log) scot td-sec. One set of parameters describing the activation process was derived from fits to the a-wave model. A double-flash paradigm was used to study inactivation mechanisms. The first flash was achromatic and varied in intensity (I(f)) from 6.1 to 13.9 ln (2.6 to 6.0 log) scot td-sec. The second flash was a short-wavelength probe held constant at 9.3 ln (4.0 log) scot td-sec. Cone components were elicited with a photopically matched long-wavelength stimulus and were computer subtracted. Recovery at each I(f) was followed by measuring the amplitude to the probe flash at various interstimulus intervals (ISI). The critical time (Tc) before the initiation of rod recovery was determined from the function relating relative rod amplitude to ISI. Recovery from activation was similar in normal subjects and in patients with rod monochromatism. Over a large range of I(f) above rod saturation, Tc increased in proportion to ln I(f). The mean slope of the function relating Tc to I(f) was 2.3 s/ln I(f) when I(f) varied between 11 and 13.9 ln scot td-sec. Patients with retinitis pigmentosa and the pro-23-his rhodopsin mutation had a decrease in the gain of activation. They also had significantly slower than normal recovery after high test flash intensities, such that the slope of the function relating Tc to ln I(f) was 12.1 seconds. Available data from other species imply that

  3. Longitudinal evaluation and assessment of cardiovascular disease in patients with homozygous familial hypercholesterolemia

    NARCIS (Netherlands)

    Kolansky, Daniel M.; Cuchel, Marina; Clark, Bernard J.; Paridon, Steve; McCrindle, Brian W.; Wiegers, Susan E.; Araujo, Luis; Vohra, Yogesh; Defesche, Joep C.; Wilson, James M.; Rader, Daniel J.

    2008-01-01

    Homozygous familial hypercholesterolemia (hoFH) is caused by mutations in the low-density lipoprotein receptor gene and is characterized by severe hypercholesterolemia from birth and onset of premature cardiovascular disease (CVD) during childhood. The onset and progression of CVD using currently

  4. Progressive hereditary spastic paraplegia caused by a homozygous KY mutation

    National Research Council Canada - National Science Library

    Yuval Yogev; Yonatan Perez; Iris Noyman; Anwar Abu Madegem; Hagit Flusser; Zamir Shorer; Eugene Cohen; Leonid Kachko; Analia Michaelovsky; Ruth Birk; Arie Koifman; Max Drabkin; Ohad Wormser; Daniel Halperin; Rotem Kadir; Ohad S Birk

    2017-01-01

    Twelve individuals of consanguineous Bedouin kindred presented with autosomal recessive progressive spastic paraplegia evident as of age 0-24 months, with spasticity of lower limbs, hyperreflexia, toe...

  5. A homozygous mutation in LTBP2 causes isolated microspherophakia.

    NARCIS (Netherlands)

    Kumar, A.; Duvvari, M.R.; Prabhakaran, V.C.; Shetty, J.S.; Murthy, G.J.; Blanton, S.H.

    2010-01-01

    Microspherophakia is an autosomal-recessive congenital disorder characterized by small spherical lens. It may be isolated or occur as part of a hereditary systemic disorder, such as Marfan syndrome, autosomal dominant and recessive forms of Weill-Marchesani syndrome, autosomal dominant glaucoma-lens

  6. SUCCESSFUL TREATMENT OF HOMOZYGOUS CYSTINURIA WITH

    African Journals Online (AJOL)

    experienced recurrent nephrolithiasis or adverse drug effects. Conclusion: We conclude that captopril can significantly decrease urinary cystine excretion in patients with homozygous cystinuria. Captopril should be considered an alternative to traditional drug management of cystinuria. Key Words: lithiasis, captopril, urinary ...

  7. Generation of an ASGR1 homozygous mutant human embryonic stem cell line WAe001-A-6 using CRISPR/Cas9

    Directory of Open Access Journals (Sweden)

    Yingying Xu

    2017-07-01

    Full Text Available The gene asialoglycoprotein receptor 1 (ASGR1 encodes a subunit of the asialoglycoprotein receptor. Here we report the generation of a human embryonic stem cell line WAe001-A-6 harbouring homozygous ASGR1 mutations using CRISPR/Cas9. The mutation involves a 37 bp deletion, resulting in a frame shift. The homozygous knockout WA01 cell line maintains a normal karyotype, typical stem cell morphology, pluripotency and differentiation potential in vitro.

  8. Homozygous c.1160C>T (P38L) in the MECP2 gene in a female Rett syndrome patient.

    Science.gov (United States)

    Bhanushali, Aparna A; Mandsaurwala, A; Das, Bibhu R

    2016-03-01

    Rett syndrome is a severe X-linked dominant neurodevelopmental disorder. Mutations in the MECP2 gene on chromosome Xq28 have been shown to be the cause of Rett syndrome. Sequencing of the MECP2 gene in a patient with clinical suspicion of Rett syndrome revealed c.1160C>T (P387L) in exon 4 of the MECP2 gene homozygously. Females with Rett syndrome are usually heterozygous for a mutation in MECP2. Uniparental disomy as a probable cause for the homozygous presence of this mutation was ruled out by quantitative fluorescence-polymerase chain reaction. Moreover to our knowledge this mutation has only been reported in males with X-linked mental retardation (MRX). We hypothesize that the presence of this mutation c.1160C>T (P387L) in the homozygous form is responsible for the Rett syndrome-like phenotype seen in this patient. This novel report reveals for the first time the homozygous presence of a mutation which has hitherto only been reported in males with MRX. Copyright © 2015 Elsevier Ltd. All rights reserved.

  9. Shaker IR T449 mutants separate C- from U-type inactivation.

    Science.gov (United States)

    Jamieson, Quentin; Jones, Stephen W

    2014-04-01

    Previous studies demonstrated that slow inactivation of the Shaker potassium channel can be made ~100-fold faster or slower by point mutations at a site in the outer pore (T449). However, the discovery that two forms of slow inactivation coexist in Shaker raises the question of which inactivation process is affected by mutation. Equivalent mutations in K(V)2.1, a channel exhibiting only U-type inactivation, have minimal effects on inactivation, suggesting that mutation of Shaker T449 acts on C-type inactivation alone, a widely held yet untested hypothesis. This study reexamines mutations at Shaker T449, confirming that T449A speeds inactivation and T449Y/V slow it. T449Y and T449V exhibit U-type inactivation that is enhanced by high extracellular potassium, in contrast to C-type inactivation in T449A which is inhibited by high potassium. Automated parameter estimation for a 12-state Markov model suggests that U-type inactivation occurs mainly from closed states upon weak depolarization, but primarily from the open state at positive voltages. The model also suggests that WT channels, which in this study exhibit mostly C-type inactivation, recover from inactivation through closed-inactivated states, producing voltage-dependent recovery. This suggests that both C-type and U-type inactivation involve both open-inactivated and closed-inactivated states.

  10. Mitotic recombination and compound-heterozygous mutations are predominant NF1-inactivating mechanisms in children with juvenile myelomonocytic leukemia and neurofibromatosis type 1

    OpenAIRE

    Steinemann, Doris; Arning, Larissa; Praulich, Inka; Stuhrmann, Manfred; Hasle, Henrik; Starý, Jan; Schlegelberger, Brigitte; Niemeyer, Charlotte M.; Flotho, Christian

    2009-01-01

    Children with neurofibromatosis type 1 (NF-1), being constitutionally deficient for one allele of the NF1 gene, are at greatly increased risk of juvenile myelomonocytic leukemia (JMML). NF1 is a negative regulator of RAS pathway activity, which has a central role in JMML. To further clarify the role of biallelic NF1 gene inactivation in the pathogenesis of JMML, we investigated the somatic NF1 lesion in 10 samples from children with JMML/NF-1. We report that two-thirds of somatic events invol...

  11. Characterization of mutations in the CPO gene in British patients demonstrates absence of genotype-phenotype correlation and identifies relationship between hereditary coproporphyria and harderoporphyria.

    Science.gov (United States)

    Lamoril, J; Puy, H; Whatley, S D; Martin, C; Woolf, J R; Da Silva, V; Deybach, J C; Elder, G H

    2001-05-01

    Hereditary coproporphyria (HCP) is the least common of the autosomal dominant acute hepatic porphyrias. It results from mutations in the CPO gene that encodes the mitochondrial enzyme, coproporphyrinogen oxidase. A few patients have also been reported who are homoallellic or heteroallelic for CPO mutations and are clinically distinct from those with HCP. In such patients the presence of a specific mutation (K404E) on one or both alleles produces a neonatal hemolytic anemia that is known as "harderoporphyria"; mutations on both alleles elsewhere in the gene give rise to the "homozygous" variant of HCP. The molecular relationship between these disorders and HCP has not been defined. We describe the molecular investigation and clinical features of 17 unrelated British patients with HCP. Ten novel and four previously reported CPO mutations, together with three previously unrecognized single-nucleotide polymorphisms, were identified in 15 of the 17 patients. HCP is more heterogeneous than other acute porphyrias, with all but one mutation being restricted to a single family, with a predominance of missense mutations (10 missense, 2 nonsense, 1 frameshift, and 1 splice site). Of the four known mutations, one (R331W) has previously been reported to cause disease only in homozygotes. Heterologous expression of another mutation (R401W) demonstrated functional properties similar to those of the K404E harderoporphyria mutation. In all patients, clinical presentation was uniform, in spite of the wide range (1%-64%) of residual coproporphyrinogen oxidase activity, as determined by heterologous expression. Our findings add substantially to knowledge of the molecular epidemiology of HCP, show that single copies of CPO mutations that are known or predicted to cause "homozygous" HCP or harderoporphyria can produce typical HCP in adults, and demonstrate that the severity of the phenotype does not correlate with the degree of inactivation by mutation of coproporphyrinogen oxidase.

  12. Commentary on "Biallelic inactivation of BRCA2 in platinum-sensitive metastatic castration-resistant prostate cancer". Cheng HH, Pritchard CC, Boyd T, Nelson PS, Montgomery B. Eur Urol. Jun 2016;69(6):992-5.

    Science.gov (United States)

    Freedland, Stephen; Aronson, William

    2017-08-01

    Understanding the molecular underpinnings of sensitivity to specific therapies will advance the goal of precision medicine in prostate cancer (PCa). We identified 3 patients with metastatic castration-resistant PCa (mCRPC) who achieved an exceptional response to platinum chemotherapy (not first-line treatment for PCa), despite disease progression on prior standard therapies. Using targeted next-generation sequencing on the primary and metastatic tumors, we found that all 3 patients had biallelic inactivation of BRCA2, a tumor suppressor gene critical for homologous DNA repair. Notably, 2 had germline BRCA2 mutations, including a patient without compelling family history who was diagnosed at age 66 year. The third patient had somatic BRCA2 homozygous copy loss. Biallelic BRCA2 inactivation in mCRPC warrants further exploration as a predictive biomarker for sensitivity to platinum chemotherapy. Copyright © 2017 Elsevier Inc. All rights reserved.

  13. TP53 mutations, tetraploidy and homologous recombination repair defects in early stage high-grade serous ovarian cancer

    Science.gov (United States)

    Chien, Jeremy; Sicotte, Hugues; Fan, Jian-Bing; Humphray, Sean; Cunningham, Julie M.; Kalli, Kimberly R.; Oberg, Ann L.; Hart, Steven N.; Li, Ying; Davila, Jaime I.; Baheti, Saurabh; Wang, Chen; Dietmann, Sabine; Atkinson, Elizabeth J.; Asmann, Yan W.; Bell, Debra A.; Ota, Takayo; Tarabishy, Yaman; Kuang, Rui; Bibikova, Marina; Cheetham, R. Keira; Grocock, Russell J.; Swisher, Elizabeth M.; Peden, John; Bentley, David; Kocher, Jean-Pierre A.; Kaufmann, Scott H.; Hartmann, Lynn C.; Shridhar, Viji; Goode, Ellen L.

    2015-01-01

    To determine early somatic changes in high-grade serous ovarian cancer (HGSOC), we performed whole genome sequencing on a rare collection of 16 low stage HGSOCs. The majority showed extensive structural alterations (one had an ultramutated profile), exhibited high levels of p53 immunoreactivity, and harboured a TP53 mutation, deletion or inactivation. BRCA1 and BRCA2 mutations were observed in two tumors, with nine showing evidence of a homologous recombination (HR) defect. Combined Analysis with The Cancer Genome Atlas (TCGA) indicated that low and late stage HGSOCs have similar mutation and copy number profiles. We also found evidence that deleterious TP53 mutations are the earliest events, followed by deletions or loss of heterozygosity (LOH) of chromosomes carrying TP53, BRCA1 or BRCA2. Inactivation of HR appears to be an early event, as 62.5% of tumours showed a LOH pattern suggestive of HR defects. Three tumours with the highest ploidy had little genome-wide LOH, yet one of these had a homozygous somatic frame-shift BRCA2 mutation, suggesting that some carcinomas begin as tetraploid then descend into diploidy accompanied by genome-wide LOH. Lastly, we found evidence that structural variants (SV) cluster in HGSOC, but are absent in one ultramutated tumor, providing insights into the pathogenesis of low stage HGSOC. PMID:25916844

  14. Abetalipoproteinemia and homozygous hypobetalipoproteinemia: a framework for diagnosis and management.

    Science.gov (United States)

    Lee, Jooho; Hegele, Robert A

    2014-05-01

    Abetalipoproteinemia (ABL; OMIM 200100) and homozygous hypobetalipoproteinemia (HHBL; OMIM 107730) are rare diseases characterized by hypocholesterolemia and malabsorption of lipid-soluble vitamins leading to retinal degeneration, neuropathy and coagulopathy. Hepatic steatosis is also common. The root cause of both disorders is improper packaging and secretion of apolipoprotein (apo) B-containing lipoprotein particles due to mutations either in both alleles of the MTP (alias MTTP) gene encoding microsomal triglyceride transfer protein (MTP) or both alleles of the APOB gene itself in the case of ABL and HHBL, respectively. Clinical diagnosis is based on signs and symptoms, acanthocytosis on blood smear, and virtually absent apo B-containing lipoproteins, including chylomicrons, very low density lipoprotein and low density lipoprotein. Obligate heterozygote parents of ABL patients usually have normal lipids consistent with autosomal recessive inheritance, while heterozygous parents of HHBL patients typically have half normal levels of apo B-containing lipoproteins consistent with autosomal co-dominant inheritance. Definitive diagnosis involves sequencing the MTP and APOB genes, for which >30 and >60 mutations have been described for ABL and HHBL, respectively. Follow-up includes monitoring for ophthalmologic, neurologic, hematologic, and hepatic complications, as well as compliance with treatment. Investigations include lipid profile, serum transaminases, markers for lipid-soluble vitamins, and periodic instrumental assessment of ocular and neurological function. Mainstays of treatment include adherence to a low-fat diet, and supplementation with essential fatty acids and high oral doses of fat soluble vitamins. Prognosis is variable, but early diagnosis and strict adherence to treatment can recover normal neurological function and halt disease progression.

  15. X-inactivation patterns in female Leber`s hereditary optic neuropathy patients do not support a strong X-linked determinant

    Energy Technology Data Exchange (ETDEWEB)

    Pegoraro, E.; Hoffman, E.P. [Univ. of Pittsburgh School of Medicine, PA (United States); Carelli, V.; Cortelli, P. [Univ. of Bologna (Italy)] [and others

    1996-02-02

    Leber`s hereditary optic neuropathy (LHON) accounts for about 3% of the cases of blindness in young adult males. The underlying mitochondrial pathogenesis of LHON has been well studied, with specific mitochondrial DNA (mtDNA) mutations of structural genes described and well characterized. However, enigmatic aspects of the disease are not explained by mutation data, such as the higher proportion of affected males, the later onset of the disease in females, and the presence of unaffected individuals with a high proportion of mutant mtDNA. A hypothesis which has been put forward to explain the unusual disease expression is a dual model of mtDNA and X-linked nuclear gene inheritance. If a nuclear X-linked modifier gene influences the expression of the mitochondrial-linked mutant gene then the affected females should be either homozygous for the nuclear determinant, or if heterozygous, lyonization should favor the mutant X. In order to determine if an X-linked gene predisposes to LHON phenotype we studied X-inactivation patterns in 35 females with known mtDNA mutations from 10 LHON pedigrees. Our results do not support a strong X-linked determinant in LHON cause: 2 of the 10 (20%) manifesting carriers showed skewing of X-inactivation, as did 3 of the 25 (12%) nonmanifesting carriers. 39 refs., 2 figs., 1 tab.

  16. Epistatic association mapping in homozygous crop cultivars.

    Directory of Open Access Journals (Sweden)

    Hai-Yan Lü

    Full Text Available The genetic dissection of complex traits plays a crucial role in crop breeding. However, genetic analysis and crop breeding have heretofore been performed separately. In this study, we designed a new approach that integrates epistatic association analysis in crop cultivars with breeding by design. First, we proposed an epistatic association mapping (EAM approach in homozygous crop cultivars. The phenotypic values of complex traits, along with molecular marker information, were used to perform EAM. In our EAM, all the main-effect quantitative trait loci (QTLs, environmental effects, QTL-by-environment interactions and QTL-by-QTL interactions were included in a full model and estimated by empirical Bayes approach. A series of Monte Carlo simulations was performed to confirm the reliability of the new method. Next, the information from all detected QTLs was used to mine novel alleles for each locus and to design elite cross combination. Finally, the new approach was adopted to dissect the genetic basis of seed length in 215 soybean cultivars obtained, by stratified random sampling, from 6 geographic ecotypes in China. As a result, 19 main-effect QTLs and 3 epistatic QTLs were identified, more than 10 novel alleles were mined and 3 elite parental combinations, such as Daqingdou and Zhengzhou790034, were predicted.

  17. [Analysis of USH2A gene mutation in a Chinese family affected with Usher syndrome].

    Science.gov (United States)

    Li, Pengcheng; Liu, Fei; Zhang, Mingchang; Wang, Qiufen; Liu, Mugen

    2015-08-01

    To investigate the disease-causing mutation in a Chinese family affected with Usher syndrome type II. All of the 11 members from the family underwent comprehensive ophthalmologic examination and hearing test, and their genomic DNA were isolated from venous leukocytes. PCR and direct sequencing of USH2A gene were performed for the proband. Wild type and mutant type minigene vectors containing exon 42, intron 42 and exon 43 of the USH2A gene were constructed and transfected into Hela cells by lipofectamine reagent. Reverse transcription (RT)-PCR was carried out to verify the splicing of the minigenes. Pedigree analysis and clinical diagnosis indicated that the patients have suffered from autosomal recessive Usher syndrome type II. DNA sequencing has detected a homozygous c.8559-2A>G mutation of the USH2A gene in the proband, which has co-segregated with the disease in the family. The mutation has affected a conserved splice site in intron 42, which has led to inactivation of the splice site. Minigene experiment has confirmed the retaining of intron 42 in mature mRNA. The c.8559-2A>G mutation in the USH2A gene probably underlies the Usher syndrome type II in this family. The splice site mutation has resulted in abnormal splicing of USH2A pre-mRNA.

  18. Generation of two H1 hESC sublines carrying a heterozygous and homozygous knock-out of RB1

    Directory of Open Access Journals (Sweden)

    Laura Steenpass

    2017-12-01

    Full Text Available Retinoblastoma is a childhood cancer of the retina caused by biallelic inactivation of the tumor suppressor gene RB1. In heritable retinoblastoma, one allele is inherited in mutant form via one of the parental germ cells. To study molecular mechanisms in retinoblastoma, two sublines of H1 hESCs were generated, carrying a knock-out allele of RB1 in the heterozygous or homozygous state. Exon 3 of RB1 was targeted and modified by nucleotide deletions using the CRISPR/Cas9 nuclease system. Based on a nearby single nucleotide polymorphism, the modification could be assigned to one allele.

  19. Filaggrin loss-of-function mutations, atopic dermatitis and risk of actinic keratosis

    DEFF Research Database (Denmark)

    Andersen, Y M F; Egeberg, A; Balslev, E

    2017-01-01

    BACKGROUND: Common loss-of-function mutations in filaggrin gene (FLG) represent a strong genetic risk factor for atopic dermatitis (AD). Homozygous mutation carriers typically display ichthyosis vulgaris (IV) and many have concomitant AD. Previously, homozygous, but not heterozygous, filaggrin gene...

  20. Inactivation Data.xlsx

    Data.gov (United States)

    U.S. Environmental Protection Agency — The data set is a spreadsheet that contains results of inactivation experiments that were conducted to to determine the effectiveness of chlorine in inactivating B....

  1. Heterozygous and homozygous JAK2(V617F states modeled by induced pluripotent stem cells from myeloproliferative neoplasm patients.

    Directory of Open Access Journals (Sweden)

    Joseph Saliba

    Full Text Available JAK2(V617F is the predominant mutation in myeloproliferative neoplasms (MPN. Modeling MPN in a human context might be helpful for the screening of molecules targeting JAK2 and its intracellular signaling. We describe here the derivation of induced pluripotent stem (iPS cell lines from 2 polycythemia vera patients carrying a heterozygous and a homozygous mutated JAK2(V617F, respectively. In the patient with homozygous JAK2(V617F, additional ASXL1 mutation and chromosome 20 allowed partial delineation of the clonal architecture and assignation of the cellular origin of the derived iPS cell lines. The marked difference in the response to erythropoietin (EPO between homozygous and heterozygous cell lines correlated with the constitutive activation level of signaling pathways. Strikingly, heterozygous iPS cells showed thrombopoietin (TPO-independent formation of megakaryocytic colonies, but not EPO-independent erythroid colony formation. JAK2, PI3K and HSP90 inhibitors were able to block spontaneous and EPO-induced growth of erythroid colonies from GPA(+CD41(+ cells derived from iPS cells. Altogether, this study brings the proof of concept that iPS can be used for studying MPN pathogenesis, clonal architecture, and drug efficacy.

  2. A novel MHC class I-like gene is mutated in patients with hereditary haemochromatosis.

    Science.gov (United States)

    Feder, J N; Gnirke, A; Thomas, W; Tsuchihashi, Z; Ruddy, D A; Basava, A; Dormishian, F; Domingo, R; Ellis, M C; Fullan, A; Hinton, L M; Jones, N L; Kimmel, B E; Kronmal, G S; Lauer, P; Lee, V K; Loeb, D B; Mapa, F A; McClelland, E; Meyer, N C; Mintier, G A; Moeller, N; Moore, T; Morikang, E; Prass, C E; Quintana, L; Starnes, S M; Schatzman, R C; Brunke, K J; Drayna, D T; Risch, N J; Bacon, B R; Wolff, R K

    1996-08-01

    Hereditary haemochromatosis (HH), which affects some 1 in 400 and has an estimated carrier frequency of 1 in 10 individuals of Northern European descent, results in multi-organ dysfunction caused by increased iron deposition, and is treatable if detected early. Using linkage-disequilibrium and full haplotype analysis, we have identified a 250-kilobase region more than 3 megabases telomeric of the major histocompatibility complex (MHC) that is identical-by-descent in 85% of patient chromosomes. Within this region, we have identified a gene related to the MHC class I family, termed HLA-H, containing two missense alterations. One of these is predicted to inactivate this class of proteins and was found homozygous in 83% of 178 patients. A role of this gene in haemochromatosis is supported by the frequency and nature of the major mutation and prior studies implicating MHC class I-like proteins in iron metabolism.

  3. Lumacaftor-Ivacaftor in Patients with Cystic Fibrosis Homozygous for Phe508del CFTR

    DEFF Research Database (Denmark)

    Wainwright, Claire E; Elborn, J Stuart; Ramsey, Bonnie W

    2015-01-01

    BACKGROUND: Cystic fibrosis is a life-limiting disease that is caused by defective or deficient cystic fibrosis transmembrane conductance regulator (CFTR) protein activity. Phe508del is the most common CFTR mutation. METHODS: We conducted two phase 3, randomized, double-blind, placebo......-controlled studies that were designed to assess the effects of lumacaftor (VX-809), a CFTR corrector, in combination with ivacaftor (VX-770), a CFTR potentiator, in patients 12 years of age or older who had cystic fibrosis and were homozygous for the Phe508del CFTR mutation. In both studies, patients were randomly...... treatment and placebo with respect to the mean absolute improvement in the percentage of predicted FEV1 ranged from 2.6 to 4.0 percentage points (Ppulmonary exacerbations...

  4. Dietary factors and truncating APC mutations in sporadic colorectal adenomas.

    NARCIS (Netherlands)

    Diergaarde, B.; Tiemersma, E.W.; Braam, H.; Muijen, G.N.P. van; Nagengast, F.M.; Kok, F.J.; Kampman, E.

    2005-01-01

    Inactivating mutations in APC are thought to be early, initiating events in colorectal carcinogenesis. To gain insight into the relationship between diet and inactivating APC mutations, we evaluated associations between dietary factors and the occurrence of these mutations in a Dutch case-control

  5. Dietary factors and Truncating APC Mutations in Sporadic Colorectal Adenomas

    NARCIS (Netherlands)

    Diergaarde, B.; Tiemersma, E.W.; Braam, H.; Muijen, van G.N.P.; Nagengast, F.M.; Kok, F.J.; Kampman, E.

    2005-01-01

    Inactivating mutations in APC are thought to be early, initiating events in colorectal carcinogenesis. To gain insight into the relationship between diet and inactivating APC mutations, we evaluated associations between dietary factors and the occurrence of these mutations in a Dutch case-control

  6. Homozygous antithrombin deficiency in adolescents presenting with lower extremity thrombosis and renal complications: two case reports from Turkey.

    Science.gov (United States)

    Sarper, Nazan; Orlando, Christelle; Demirsoy, Uğur; Gelen, Sema A; Jochmans, Kristin

    2014-04-01

    We present 2 cases of lower extremity deep venous thrombosis in 2 gypsy adolescents from related families. The patients had low antithrombin activity levels and inherited homozygous antithrombin deficiency was confirmed by molecular analysis (Leu131Phe mutation). One patient had a history of nephrectomy at the age of 9 due to nonfunctioning kidney and 2 siblings died at 4 months of age. His mother had 3 fetal losses in the third trimester. The other propositus had an elder sister who suffered from postpartum deep vein thrombosis and pulmonary embolism. Heterozygous mutation was demonstrated in both parents.

  7. Qualitative analysis of mouse specific-locus mutations: information on genetic organization, gene expression, and the chromosomal nature of induced lesions

    Energy Technology Data Exchange (ETDEWEB)

    Russell, L.B.

    1982-01-01

    Analysis of mouse specific-locus (SL) mutations at three loci has identified over 33 distinct complementation groups - most of which are probably overlapping deficiencies - and 13 to 14 new functional units. The complementation maps that have been generated for the d-se and c regions include numerous vital functions; however, some of the genes in these regions are non-vital. At such loci, hypomorphic mutants must represent intragenic alterations, and some viable nulls could conceivably be intragenic lesions also. Analysis of SL mutations has provided information on genetic expression. Homozygous deficiencies can be completely viable or can kill at any one of a range of developmental stages. Heterozygonus deficiencies of up to 6 cM or more in genetic length have been recovered and propagated. The time of death of homozygous and the degree of inviability of heterozygous deficiencies are related more to specific content of the missing segment than to its length. Combinations of deficiencies with x-autosome translocations that inactivate the homologous region in a mosaic fashion have shown that organismic lethals are not necessarily cell lethal. The spectrum of mutations induced depends on the nature of the mutagen and the type of germ cell exposed. Radiation of spermatogonia produces intragenic as well as null mutations. Spontaneous mutations have an admixture of types not present in populations of mutations induced in germ cells, and this raises doubts concerning the accuracy of doubling-dose calculations in genetic risk estimation. The analysis of SL mutations has yielded genetic tools for the construction of detailed gene-dosage series, cis-trans comparisons, the mapping of known genes and identification of new genes, genetic rescue of various types, and the identification and isolation of DNA sequences. (ERB)

  8. ALS2 mutations

    Science.gov (United States)

    Schneider, Susanne A.; Carr, Lucinda; Deuschl, Guenther; Hopfner, Franziska; Stamelou, Maria; Wood, Nicholas W.; Bhatia, Kailash P.

    2014-01-01

    Objective: To determine the genetic etiology in 2 consanguineous families who presented a novel phenotype of autosomal recessive juvenile amyotrophic lateral sclerosis associated with generalized dystonia. Methods: A combination of homozygosity mapping and whole-exome sequencing in the first family and Sanger sequencing of candidate genes in the second family were used. Results: Both families were found to have homozygous loss-of-function mutations in the amyotrophic lateral sclerosis 2 (juvenile) (ALS2) gene. Conclusions: We report generalized dystonia and cerebellar signs in association with ALS2-related disease. We suggest that the ALS2 gene should be screened for mutations in patients who present with a similar phenotype. PMID:24562058

  9. Mutational analysis of the extracellular Ca{sup 2+}-sensing receptor gene in human parathyroid tumors

    Energy Technology Data Exchange (ETDEWEB)

    Hosokawa, Yoshitaka; Arnold, A. [Massachusetts General Hospital and Harvard Medical School, Boston, MA (United States); Pollak, M.R.; Brown, E.M. [Brigham and Women`s Hospital, Boston, MA (United States)

    1995-10-01

    Despite recent progress, such as the identification of PRAD1/cyclin D1 as a parathyroid oncogene, it is likely that many genes involved in the molecular pathogenesis of parathyroid tumors remain unknown. Individuals heterozygous for inherited mutations in the extracellular Ca{sup 2+}-sensing receptor gene that reduce its biological activity exhibit a disorder termed familial hypocalciuric hypercalcemia or familial benign hypercalcemia, which is characterized by reduced responsiveness of parathyroid and kidney to calcium and by PTH-dependent hypercalcemia. Those who are homozygous for such mutations present with neonatal severe hyperparathyroidism and have marked parathroid hypercellularity. Thus, the Ca{sup 2+}-sensing receptor gene is a candidate parathyroid tumor suppressor gene, with inactivating mutations plausibly explaining set-point abnormalities in the regulation of both parathyroid cellular proliferation and PTH secretion by extracellular Ca{sup 2+} similar to those seen in hyperparathyroidism. Using a ribonuclease A protection assay that has detected multiple mutations in the Ca{sup 2+}-sensing receptor gene in familial hypocalciuric hypercalcemia and covers more than 90% of its coding region, we sought somatic mutations in this gene in a total of 44 human parathyroid tumors (23 adenomas, 4 carcinomas, 5 primary hyperplasias, and 12 secondary hyperplasias). No such mutations were detected in these 44 tumors. Thus, our studies suggest that somatic mutation of the Ca{sup 2+}-sensing receptor gene does not commonly contribute to the pathogenesis of sporadic parathyroid tumors. As such, PTH set-point dysfunction in parathroid tumors may well be secondary to other clonal proliferative defects and/or mutations in other components of the extracellular Ca{sup 2+}-sensing pathway. 29 refs., 2 figs.

  10. Homozygous familial hypercholesterolemia associated with symmetric subcutaneous lipomatosis

    Directory of Open Access Journals (Sweden)

    Noha Mohammed Dawoud

    2015-01-01

    Full Text Available Homozygous familial hypercholesterolemia is an autosomal dominant disorder of lipid metabolism, characterized by reduced clearance of low-density lipoprotein-cholesterol and a high risk of rapid development of cardiovascular diseases. Its incidence is relatively rare and estimated to be one in one million in general populations. Here, we report homozygous familial hypercholesterolemia in two Egyptian young siblings, presented with cutaneous, tendinous xanthomas, and corneal arcus. One of them has symmetric subcutaneous lipomatosis, which has not been reported before in association with familial hypercholesterolemia.

  11. Molecular mechanisms of renal and extrarenal manifestations caused by inactivation of the electrogenic Na+-HCO3- cotransporter NBCe1

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    George eSeki

    2013-10-01

    Full Text Available The electrogenic Na+-HCO3- cotransporter NBCe1 plays an essential role in bicarbonate absorption from renal proximal tubules, but also mediates the other biological processes in extrarenal tissues such as bicarbonate secretion from pancreatic ducts, maintenance of tissue homeostasis in eye, enamel maturation in teeth, or local pH regulation in synapses. Homozygous mutation in NBCe1 cause proximal renal tubular acidosis (pRTA associated with extrarenal manifestations such as short stature, ocular abnormalities, enamel abnormalities, and migraine. Functional analyses of NBCe1 mutants using different expression systems suggest that at least a 50% reduction of the transport activity may be required to induce severe pRTA. In addition to functional impairments, some NBCe1 mutants show trafficking defects. Some of the pRTA-related NBCe1 mutants showing the cytoplasmic retention have been shown to exert a dominant negative effect through hetero-oligomer complexes with wild-type NBCe1 that may explain the occurrence of extrarenal manifestations in the heterozygous carries of NBCe1 mutations. Both NBCe1 knockout and W516X knockin mice showed very severe pRTA and reproduced most of the clinical manifestations observed in human pRTA patients. Functional analysis on isolated renal proximal tubules from W516X knockin mice directly confirmed the indispensable role of NBCe1 in bicarbonate absorption from this nephron segment. In this review, we will focus on the molecular mechanisms underling the renal and extrarenal manifestations caused by NBCe1 inactivation.

  12. Factor V Leiden, Prothrombin and MTHFR Mutation in Patients with Preeclamsia, Intrauterine Growth Restriction and Placental Abruption

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    Vesna Livrinova

    2015-09-01

    CONCLUSION: The presence of mutation MTHFR homozygous could increase the risk for development of IUGR and mutation of Factor V Leiden for placental abruption. Further investigations with more patients are warranted.

  13. Defective haematopoiesis in fetal liver resulting from inactivation of the EKLF gene.

    Science.gov (United States)

    Nuez, B; Michalovich, D; Bygrave, A; Ploemacher, R; Grosveld, F

    1995-05-25

    Erythroid Krüppel-like factor (EKLF) was originally isolated from erythroid cell RNA by differential screening and shown to be erythroid-specific, although a low level of EKLF was found in mast cell lines. EKLF contains three zinc-fingers homologous to those found in the Krüppel family of transcription factors. Because it binds the sequence CCACACCCT, EKLF may affect erythroid development as a result of its ability to bind to the CAC box in the promoter of the beta-globin gene. Mutation of this element leads to reduced beta-globin expression and it appears to mediate the effect of the globin locus control region on the promoter. Here we inactivate the EKLF gene through insertion of a lacZ reporter gene by homologous recombination in embryonic stem (ES) cells. Heterozygous EKLF+/- mice show that the reporter gene is expressed in a developmentally specific manner in all types of erythroblasts in the fetal liver and adult bone marrow. Homozygous EKLF-/- mice appear normal during the embryonic stage of haematopoiesis in the yolk sac, but develop a fatal anaemia during early fetal life when haematopoiesis has switched to the fetal liver. Enucleated erythrocytes are formed but these do not contain the proper amount of haemoglobin. We conclude that the transcription factor EKLF is essential for the final steps of definitive erythropoiesis in fetal liver.

  14. Genetic inactivation of the Fanconi anemia gene FANCC identified in the hepatocellular carcinoma cell line HuH-7 confers sensitivity towards DNA-interstrand crosslinking agents

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    Bassermann Florian

    2010-05-01

    Full Text Available Abstract Background Inactivation of the Fanconi anemia (FA pathway through defects in one of 13 FA genes occurs at low frequency in various solid cancer entities among the general population. As FA pathway inactivation confers a distinct hypersensitivity towards DNA interstrand-crosslinking (ICL-agents, FA defects represent rational targets for individualized therapeutic strategies. Except for pancreatic cancer, however, the prevalence of FA defects in gastrointestinal (GI tumors has not yet been systematically explored. Results A panel of GI cancer cell lines was screened for FA pathway inactivation applying FANCD2 monoubiquitination and FANCD2/RAD51 nuclear focus formation and a newly identified FA pathway-deficient cell line was functionally characterized. The hepatocellular carcinoma (HCC line HuH-7 was defective in FANCD2 monoubiquitination and FANCD2 nuclear focus formation but proficient in RAD51 focus formation. Gene complementation studies revealed that this proximal FA pathway inactivation was attributable to defective FANCC function in HuH-7 cells. Accordingly, a homozygous inactivating FANCC nonsense mutation (c.553C > T, p.R185X was identified in HuH-7, resulting in partial transcriptional skipping of exon 6 and leading to the classic cellular FA hypersensitivity phenotype; HuH-7 cells exhibited a strongly reduced proliferation rate and a pronounced G2 cell cycle arrest at distinctly lower concentrations of ICL-agents than a panel of non-isogenic, FA pathway-proficient HCC cell lines. Upon retroviral transduction of HuH-7 cells with FANCC cDNA, FA pathway functions were restored and ICL-hypersensitivity abrogated. Analyses of 18 surgical HCC specimens yielded no further examples for genetic or epigenetic inactivation of FANCC, FANCF, or FANCG in HCC, suggesting a low prevalence of proximal FA pathway inactivation in this tumor type. Conclusions As the majority of HCC are chemoresistant, assessment of FA pathway function in HCC could

  15. Hepatitis B Virus Infection In Patients With Homozygous Sickle Cell ...

    African Journals Online (AJOL)

    Nnebe-Agumadu U H, and Abiodun P O. Hepatitis B Virus Infection in Patients with Homozygous Sickle Cell Disease (HbSS): Need for Intervention. Annals Biomedical Sciences 2002; 1:79-87. This is a prospective study of 213 patients with sickle cell anaemia (SCA) (112 males and 101 females) aged 6 months to 18 years ...

  16. A Report of Two Children with Severe Homozygous Familial Hypercholesterolemia

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    Noormohammad Noori

    2013-04-01

    Full Text Available Familial hypercholesterolemia (FH is an autosomal disorder that causes severe elevations in total cholesterol and low- density lipoprotein. FH is one of the primary risk factors for premature coronary artery disease in children and adults which requires early diagnosis and appropriate medical intervention. In this article, we report two cases of homozygous familial hypercholesterolemia.

  17. Multi-kilobase homozygous targeted gene replacement in human induced pluripotent stem cells.

    Science.gov (United States)

    Byrne, Susan M; Ortiz, Luis; Mali, Prashant; Aach, John; Church, George M

    2015-02-18

    Sequence-specific nucleases such as TALEN and the CRISPR/Cas9 system have so far been used to disrupt, correct or insert transgenes at precise locations in mammalian genomes. We demonstrate efficient 'knock-in' targeted replacement of multi-kilobase genes in human induced pluripotent stem cells (iPSC). Using a model system replacing endogenous human genes with their mouse counterpart, we performed a comprehensive study of targeting vector design parameters for homologous recombination. A 2.7 kilobase (kb) homozygous gene replacement was achieved in up to 11% of iPSC without selection. The optimal homology arm length was around 2 kb, with homology length being especially critical on the arm not adjacent to the cut site. Homologous sequence inside the cut sites was detrimental to targeting efficiency, consistent with a synthesis-dependent strand annealing (SDSA) mechanism. Using two nuclease sites, we observed a high degree of gene excisions and inversions, which sometimes occurred more frequently than indel mutations. While homozygous deletions of 86 kb were achieved with up to 8% frequency, deletion frequencies were not solely a function of nuclease activity and deletion size. Our results analyzing the optimal parameters for targeting vector design will inform future gene targeting efforts involving multi-kilobase gene segments, particularly in human iPSC. © The Author(s) 2014. Published by Oxford University Press on behalf of Nucleic Acids Research.

  18. Tezacaftor-Ivacaftor in Patients with Cystic Fibrosis Homozygous for Phe508del.

    Science.gov (United States)

    Taylor-Cousar, Jennifer L; Munck, Anne; McKone, Edward F; van der Ent, Cornelis K; Moeller, Alexander; Simard, Christopher; Wang, Linda T; Ingenito, Edward P; McKee, Charlotte; Lu, Yimeng; Lekstrom-Himes, Julie; Elborn, J Stuart

    2017-11-23

    Combination treatment with the cystic fibrosis transmembrane conductance regulator (CFTR) modulators tezacaftor (VX-661) and ivacaftor (VX-770) was designed to target the underlying cause of disease in patients with cystic fibrosis. In this phase 3, randomized, double-blind, multicenter, placebo-controlled, parallel-group trial, we evaluated combination therapy with tezacaftor and ivacaftor in patients 12 years of age or older who had cystic fibrosis and were homozygous for the CFTR Phe508del mutation. Patients were randomly assigned in a 1:1 ratio to receive either 100 mg of tezacaftor once daily and 150 mg of ivacaftor twice daily or matched placebo for 24 weeks. The primary end point was the absolute change in the percentage of the predicted forced expiratory volume in 1 second (FEV1) through week 24 (calculated in percentage points); relative change in the percentage of the predicted FEV1 through week 24 (calculated as a percentage) was a key secondary end point. Of the 510 patients who underwent randomization, 509 received tezacaftor-ivacaftor or placebo, and 475 completed 24 weeks of the trial regimen. The mean FEV1 at baseline was 60.0% of the predicted value. The effects on the absolute and relative changes in the percentage of the predicted FEV1 in favor of tezacaftor-ivacaftor over placebo were 4.0 percentage points and 6.8%, respectively (Pcystic fibrosis and were homozygous for the CFTR Phe508del mutation. (Funded by Vertex Pharmaceuticals; EVOLVE ClinicalTrials.gov number, NCT02347657 .).

  19. Stepwise decrease in daptomycin susceptibility in clinical Staphylococcus aureus isolates associated with an initial mutation in rpoB and a compensatory inactivation of the clpX gene

    DEFF Research Database (Denmark)

    Bæk, Kristoffer Torbjørn; Thøgersen, Louise; Mogensen, René G.

    2015-01-01

    , reduced expression of virulence traits, induced expression of the stress-associated transcriptional regulator, Spx, and slow growth. A subsequent acquired loss-of-function mutation in clpX partly alleviated the growth defect conferred by the rpoB mutation without changing antibiotic susceptibility...

  20. A high frequency of XO offspring from X(Paf)Y* male mice: evidence that the Paf mutation involves an inversion spanning the X PAR boundary.

    Science.gov (United States)

    Burgoyne, P S; Evans, E P

    2000-01-01

    It has previously been reported that 19% of the daughters of males carrying the X-linked mutation patchy fur (Paf) are XO with a maternally derived X chromosome. We now report that hemizygous Paf males that also carry the variant Y chromosome Y*, show a much increased XO production ( approximately 40% of daughters). We hypothesize that the Paf mutation is associated with an inversion spanning the pseudoautosomal region (PAR) boundary, and that this leads to preferential crossing over between the resulting inverted region of PAR and an equivalent inverted PAR region within the compound Y* PAR. This would lead to the production of dicentric X and acentric Y products and consequent sex chromosome loss. This interpretation is supported by analysis of the sex chromosome complements at the second meiotic metaphase, which revealed a high incidence of dicentrics. Another curious feature of the Paf mutation is that mice that are homozygous Paf have more hair than mice that are hemizygous Paf. This can be explained if the Paf mutation is a hypomorphic mutation that escapes X inactivation because, unlike the wild type allele, it is now located within the PAR. Copyright 2001 S. Karger AG, Basel

  1. Skewed X-inactivation in a family with DLG3-associated X-linked intellectual disability.

    Science.gov (United States)

    Gieldon, Laura; Mackenroth, Luisa; Betcheva-Krajcir, Elitza; Rump, Andreas; Beck-Wödl, Stefanie; Schallner, Jens; Di Donato, Nataliya; Schröck, Evelin; Tzschach, Andreas

    2017-09-01

    Mutations in DLG3 are a rare cause of non-syndromic X-linked intellectual disability (XLID) (MRX90, OMIM *300189). Only ten DLG3 mutations have been reported to date. The majority of female heterozygous mutation carriers was healthy and had random X-inactivation patterns. We report on an XLID family with a novel DLG3 mutation. The 12-year-old male index patient had moderate intellectual disability (ID) and dysmorphic features. The mutation was also present in four female relatives. A maternal aunt had moderate ID and significantly skewed X-inactivation favorably inactivating the normal DLG3 allele. The proband's healthy mother also had skewed X-inactivation but in the opposite direction (i.e., inactivation of the mutated allele). Two other female relatives had intermediate cognitive phenotypes and random X-inactivation. This family broadens the mutational and phenotypical spectrum of DLG3-associated XLID and demonstrates that heterozygous female mutation carriers can be as severely affected as males. Reports of additional families will be needed to elucidate the causes of unfavorable skewing in female XLID patients. © 2017 Wiley Periodicals, Inc.

  2. Premature Valvular Heart Disease in Homozygous Familial Hypercholesterolemia

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    Akl C. Fahed

    2017-01-01

    Full Text Available Valvular heart disease frequently occurs as a consequence of premature atherosclerosis in individuals with familial hypercholesterolemia (FH. Studies have primarily focused on aortic valve calcification in heterozygous FH, but there is paucity of data on the incidence of valvular disease in homozygous FH. We performed echocardiographic studies in 33 relatively young patients (mean age: 26 years with homozygous FH (mean LDL of 447 mg/dL, 73% on LDL apheresis to look for subclinical valvulopathy. Twenty-one patients had evidence of valvulopathy of the aortic or mitral valves, while seven subjects showed notable mitral regurgitation. Older patients were more likely to have aortic valve calcification (>21 versus ≤21 years: 59% versus 12.5%; p = 0.01 despite lower LDL levels at the time of the study (385 versus 513 mg/dL; p = 0.016. Patients with valvulopathy were older and had comparable LDL levels and a lower carotid intima-media thickness. Our data suggests that, in homozygous FH patients, valvulopathy (1 is present across a wide age spectrum and LDL levels and (2 is less likely to be influenced by lipid-lowering treatment. Echocardiographic studies that focused on aortic root thickening and stenosis and regurgitation are thus likely an effective modality for serial follow-up of subclinical valvular heart disease.

  3. Ethnicity of children with homozygous c.985A>G medium-chain acyl-CoA dehydrogenase deficiency

    DEFF Research Database (Denmark)

    Khalid, J M; Oerton, J; Cortina-Borja, M

    2008-01-01

    OBJECTIVES: It has been suggested that homozygous c.985A>G medium-chain acyl-CoA dehydrogenase deficiency (MCADD) is a disease of White ethnic origin but little is known regarding its ethnic distribution. We estimated ethnic-specific homozygous c.985A>G MCADD birth prevalence from a large-scale UK......: Sixty-four infants were c.985A>G MCADD homozygotes (overall prevalence 5.8 per 100,000 live births; 95% CI 4.4-7.2). Sixty (93%) were White, two (3%) were mixed/other and two were of unknown ethnic origin. No Asian or Black homozygotes were identified. Proportions of White, mixed/other, Asian and Black......% CI 1/74, 1/61) under Hardy-Weinberg conditions. CONCLUSION: c.985A>G homozygous MCADD is not found in Black and Asian ethnic groups that have been screened at birth in England. This is consistent with the earlier published observations suggesting that MCADD due to the c.985A>G mutation is a disease...

  4. X inactivation in Rett syndrome: A preliminary study showing partial preferential inactivation of paternal X with the M27{beta} probe

    Energy Technology Data Exchange (ETDEWEB)

    Camus, P.; Abbadi, N.; Gilgenkrantz, S. [Laboratoire de Genetique, Vandoeuvre les Nancy (France)

    1994-04-15

    Rett syndrome (RS) is a severe progressive neurological disorder occurring exclusively in females. Most cases are sporadic. The few familial cases (less than 1%) cannot be explained by a simple mode of inheritance. Several hypotheses have been proposed: X-linked male lethal mutation, maternal uniparental disomy, fresh mutation on the X chromosome, involvement of mitochondrial DNA and differential inactivation with metabolic interference of X-borne alleles. The authors have examined the pattern of X inactivation in 10 affected girls who were selected according to the clinical criteria previously described and accepted by the French Rett Scientific Committee. The X inactivation pattern was studied by analysis of methylation at the hypervariable locus DXS255 with the M27{beta} probe. The results show a more-or-less skewed inactivation of paternal X in 8 Rett females, and 2 cases of symmetrical inactivation. In control girls, inactivation was symmetrical cases and the maternal X has been preferentially inactivated in the other 2 cases. In no case was a total skewed inactivation observed. Though there was clear evidence for a preferential paternal X inactivation that was statistically significant further studies are necessary to establish a relationship between X inactivation pattern and Rett syndrome.

  5. Mutations in PCBD1 Cause Hypomagnesemia and Renal Magnesium Wasting

    NARCIS (Netherlands)

    Ferre, S.; Baaij, J.H.F. de; Ferreira, P.; Germann, R.; Klerk, J.B. De; Lavrijsen, M.; Zeeland, F. van; Venselaar, H.; Kluijtmans, L.A.; Hoenderop, J.G.J.; Bindels, R.J.M.

    2014-01-01

    Mutations in PCBD1 are causative for transient neonatal hyperphenylalaninemia and primapterinuria (HPABH4D). Until now, HPABH4D has been regarded as a transient and benign neonatal syndrome without complications in adulthood. In our study of three adult patients with homozygous mutations in the

  6. A thermosensitive mutation alters the effects of lacosamide on slow inactivation in neuronal voltage-gated sodium channels, NaV 1.2.Mena Abdelsayed1, Stanislav Sokolov1, Peter C. Ruben*1 - These authors contributed equally to this work* - Corresponding author

    Directory of Open Access Journals (Sweden)

    Mena eAbdelsayed

    2013-09-01

    Full Text Available Epilepsy is a disorder characterized by seizures and convulsions. The basis of epilepsy is an increase in neuronal excitability that, in some cases, may be caused by functional defects in neuronal voltage gated sodium channels (NaVs. The C121W mutation of the β1 subunit, in particular, gives rise to the thermosensitive generalized epilepsy with febrile seizures plus (GEFS+ phenotype. Lacosamide is used to treat epileptic seizures and is distinct from other anti-seizure drugs by targeting NaV slow-inactivation. We studied the effects of 100 µM lacosamide on the biophysical properties of NaV1.2 channels associated with either WT-β1 or the mutant C121W-β1 subunit. Biophysical parameters were measured at both normal (22 °C and elevated (34 °C temperatures to elicit the differential temperature-sensitivity of C121W. Lacosamide was less effective in NaV1.2 associated with the C121W-β1 at either temperature than in NaV1.2 + WT-β1. There is also a more potent effect by lacosamide on slow inactivation at elevated temperatures. Our data suggest a modulatory role is imparted by the β1 subunit in the interaction between the drug and the channel.

  7. Homozygous variegate porphyria presenting with developmental and language delay in childhood.

    Science.gov (United States)

    Pinder, V A E; Holden, S T; Deshpande, C; Siddiqui, A; Mellerio, J E; Wraige, E; Powell, A M

    2013-10-01

    Variegate porphyria is an autosomal dominant disorder that usually presents with photosensitivity and acute neurological crises in adulthood. It is caused by heterozygous mutations in the protoporphyrinogen oxidase gene (PPOX). A rarer variant, homozygous variegate porphyria (HVP), presents in childhood with recurrent skin blisters and scarring. More variable features of HVP are short stature, brachydactyly, nystagmus, epilepsy, developmental delay and mental retardation. We describe a child who presented with nystagmus, developmental delay and ataxia, combined with a photosensitive eruption. Analysis of porphyrins in plasma, urine and stool supported a clinical diagnosis of HVP. DNA from the patient showed that he is compound heterozygous for two novel missense mutations in the PPOX coding region: c.169G>C (p.Gly57Arg) and c.1259C>G (Pro420Arg). Interestingly, cranial magnetic resonance imaging showed an absence of myelin, a feature not previously reported in HVP, which expands the differential diagnosis of childhood hypomyelinating leucoencephalopathies. © 2013 British Association of Dermatologists.

  8. X chromosome-linked and mitochondrial gene control of Leber hereditary optic neuropathy: Evidence from segregation analysis for dependence on X chromosome inactivation

    Energy Technology Data Exchange (ETDEWEB)

    Xiangdong Bu; Rotter, J.I. (Cedars-Sinai Medical Center, Los Angeles, CA (United States) Univ. of California, Los Angeles (United States))

    1991-09-15

    Leber hereditary optic neuropathy (LHON) has been shown to involve mutation(s) of mitochondrial DNA, yet there remain several confusing aspects of its inheritance not explained by mitochondrial inheritance alone, including male predominance, reduced penetrance, and a later age of onset in females. By extending segregation analysis methods to disorders that involve both a mitochondrial and a nuclear gene locus, the authors show that the available pedigree data for LHON are most consistent with a two-locus disorder, with one responsible gene being mitochondrial and the other nuclear and X chromosome-linked. Furthermore, they have been able to extend the two-locus analytic method and demonstrate that a proportion of affected females are likely heterozygous at the X chromosome-linked locus and are affected due to unfortunate X chromosome inactivation, thus providing an explanation for the later age of onset in females. The estimated penetrance for a heterozygous female is 0.11{plus minus}0.02. The calculated frequency of the X chromosome-linked gene for LHON is 0.l08. Among affected females, 60% are expected to be heterozygous, and the remainder are expected to be homozygous at the responsible X chromosome-linked locus.

  9. Pantothenate kinase-associated neurodegeneration initially presenting as postural tremor alone in a Japanese family with homozygous N245S substitutions in the pantothenate kinase gene.

    Science.gov (United States)

    Yamashita, Satoshi; Maeda, Yasushi; Ohmori, Hiroyuki; Uchida, Yuji; Hirano, Teruyuki; Yonemura, Kiminobu; Uyama, Eiichiro; Uchino, Makoto

    2004-10-15

    We describe a 24-year-old Japanese woman with pantothenate kinase-associated neurodegeneration (PKAN) whose only early symptom was postural tremor in the right hand at around 18 years of age, leading to a diagnosis of essential tremor at age 21. Although she was treated with arotinolol hydrochloride and clonazepam, she gradually progressed to extrapyramidal and pyramidal signs several years later. T2-weighted magnetic resonance images (MRI) showed bilaterally marked hypointensity with a central region of hyperintensity in the globus pallidus, or the so-called "eye-of-the-tiger" sign. Six years have passed since the initial appearance of postural tremor, whereas she has not shown choreoathetosis, retinitis pigmentosa, optic atrophy, or seizure. Direct sequencing of the patient's genomic DNA revealed homozygous base substitutions in the pantothenate kinase gene (PANK2): the A764-->G substitution (N245S) due to consanguinity of her parents. Although the heterozygous form of this mutation has already been reported among several families, this is the first report of the homozygous mutation in a patient with atypical-type PKAN. This detailed description of the clinical features of a Japanese patient with PKAN arising from homozygous N245S mutations in PANK2 would be useful for elucidating the pathogenesis of PKAN.

  10. Molecular basis of fibrinogen Naples associated with defective thrombin binding and thrombophilia. Homozygous substitution of B beta 68 Ala----Thr.

    Science.gov (United States)

    Koopman, J; Haverkate, F; Lord, S T; Grimbergen, J; Mannucci, P M

    1992-01-01

    In an abnormal fibrinogen (fibrinogen Naples) associated with congenital thrombophilia we have identified a single base substitution (G----A) in the B beta chain gene that results in an amino acid substitution of alanine by threonine at position 68 in the B beta chain of fibrinogen. The propositus and two siblings were found to be homozygous for the mutation, whereas the parents and another sibling were found to be heterozygous. Individuals homozygous for the defect had a severe history of both arterial and venous thrombosis; heterozygous individuals had no clinical symptoms. The three homozygotes had a prolonged thrombin clotting time in plasma, whereas the heterozygotes had a normal thrombin clotting time. Fibrinopeptide A and B (FpA and FpB) release from purified fibrinogen by human alpha-thrombin was delayed in both the homozygous propositus and a heterozygous family member. Release of FpA from the normal and abnormal amino-terminal disulfide knot (NDSK) corresponded to that found with the intact fibrinogens, indicating a decreased interaction of thrombin with the NDSK part of fibrinogen Naples. Binding studies showed that fibrin from homozygous abnormal fibrinogen bound less than 10% of active site inhibited alpha-thrombin as compared with normal fibrin, while fibrin formed from heterozygous abnormal fibrinogen bound approximately 50% of alpha-thrombin. These results suggest that the mutation of B beta Ala 68----Thr affects the binding of alpha-thrombin to fibrin, and that defective binding results in a decreased release of FpA and FpB in both homozygous and heterozygous abnormal fibrinogens. Images PMID:1634610

  11. X-linked juvenile retinoschisis in a consanguineous family: phenotypic variability and report of a homozygous female patient.

    Science.gov (United States)

    Gliem, Martin; Holz, Frank G; Stöhr, Heidi; Weber, Bernhard H F; Charbel Issa, Peter

    2014-12-01

    To describe the phenotypic variability in a consanguineous family with genetically confirmed X-linked retinoschisis. Five patients, including one homozygous female, were characterized by clinical examination, optical coherence tomography, fundus autofluorescence, mapping of macular pigment optical density, electroretinography, and DNA testing. The 36-year-old male index patient showed a ring of enhanced autofluorescence and outer retinal atrophy on optical coherence tomography. Electroretinography testing revealed a reduced a/b ratio. His mother presented with a central atrophic retina with markedly reduced autofluorescence signal and a surrounding ring of enhanced autofluorescence. The 40-year-old brother of the index patient and his 2 sons showed characteristic signs for X-linked retinoschisis, including retinal schisis and a reduced a/b ratio. Genetic testing revealed a c.293C>A mutation in the RS1 gene in all affected family members while the mother of the index patient was homozygous for this mutation. X-linked retinoschisis can present with a wide phenotypic variability. Here, detailed family history and genetic testing established the diagnosis of X-linked retinoschisis despite striking differences in phenotypic presentation in affected subjects, homozygosity of one affected female, and seemingly dominant inheritance in three subsequent generations because of multiple consanguinity.

  12. Successful Treatment Of Homozygous Familial Hypercholesterolemia Using Cascade Filtration Plasmapheresis

    Directory of Open Access Journals (Sweden)

    Fatih Kardas

    2012-12-01

    Full Text Available OBJECTIVE: The aim of our study is to discuss the efficacy of low-density lipoprotein-cholesterol (LDL-C apheresis procedure using the cascade filtration system for pediatric patients with homozygous familial hypercholesterolemia (FH, and to clarify the adverse effects and difficulties. METHODS: LDL apheresis using the cascade filtration system was performed in 3 pediatric patients with homozygous FH. In total, 120 apheresis sessions were performed for all patients. RESULTS: Cascade filtration therapy significantly reduced the mean LDL-C values from 418 ± 62 mg/dl to 145 ± 43 mg/dl (p<0.05. We determined an acute mean reduction in the plasma levels of total cholesterol (57.9%, LDL cholesterol (70.8%, and high-density lipoprotein (HDL cholesterol (40.7%. Treatments were well tolerated. The most frequent clinical adverse effects were hypotension in 3 sessions (2.5%, chills/feeling cold (1.7% in 2 sessions, and nausea and vomiting in 3 sessions (2.5%. CONCLUSION: Our experience with three patients using the cascade filtration system were, good clinical outcomes, laboratory findings, safety of usage, minor adverse effects and technical problems.

  13. Homozygous Familial Hypercholesterolemia: Case Series and Review of the Literature

    Directory of Open Access Journals (Sweden)

    Carlos H. Palacio

    2011-01-01

    Full Text Available Introduction. Familial hypercholesterolemia (FH is caused by nonfunctioning low-density lipoprotein (LDL receptors, resulting in high serum cholesterol. Two types of FH are described: the heterozygous form is diagnosed in adults and responds well to medical therapy; the homozygous form is rare, diagnosed in children, and often requires multiple treatments to prevent complications. Cholesterol accumulation in tissues produces common clinical manifestations including cutaneous xanthomas, coronary artery disease, and aortic stenosis. Treatment options consist of lifestyle modifications, lipid-lowering medications, LDL aphaeresis, and orthotopic liver transplantation (OLT. Case Presentation. Two patients with FH presented at young ages due to characteristic cutaneous xanthomas. The patients underwent cardiac testing that revealed atherosclerotic changes. The patients received maximal medical therapy, but only experienced a small decrease in serum cholesterol and LDL levels. After several years of medical treatment without improvement of symptoms, the patients were listed for OLT. The transplantations were successful, and only one patient had a postoperative complication of acute rejection, treated successfully. Currently, both patients are doing well with regression of the cutaneous xanthomas and atherosclerotic changes. Conclusion. OLT is a safe and effective option for patients with homozygous FH refractory to maximal medical therapy and may represent the optimal treatment for these patients.

  14. Skin malformations in a neonatal foal tested homozygous positive for Warmblood Fragile Foal Syndrome.

    Science.gov (United States)

    Monthoux, Chloé; de Brot, Simone; Jackson, Michelle; Bleul, Ulrich; Walter, Jasmin

    2015-01-31

    Skin malformations that resembled manifestations of Ehlers-Danlos-Syndrome were described in a variety of domestic animals during the last century as cutis hyperelastica, hyperelastosis cutis, dermatosparaxis, dermal/collagen dysplasia, dermal/cutaneous asthenia or Ehlers-Danlos-like syndrome/s. In 2007, the mutation responsible for Hereditary Equine Regional Dermal Asthenia (HERDA) in Quarter Horses was discovered. Several case reports are available for similar malformations in other breeds than Quarter Horses (Draught Horses, Arabians, and Thoroughbreds) including four case reports for Warmblood horses. Since 2013, a genetic test for the Warmblood Fragile Foal Syndrome Type 1 (WFFS), interrogating the causative point mutation in the equine procollagen-lysine, 2-oxoglutarate 5-dioxygenase 1 (PLOD1, or lysyl hydroxylase 1) gene, has become available. Only limited data are available on the occurrence rate and clinical characteristics of this newly detected genetic disease in horses. In humans mutations in this gene are associated with Ehlers-Danlos Syndrome Type VI (kyphoscoliotic form). This is the first report describing the clinical and histopathological findings in a foal confirmed to be homozygous positive for WFFS. The Warmblood filly was born with very thin, friable skin, skin lesions on the legs and the head, and an open abdomen. These abnormalities required euthanasia just after delivery. Histologic examination revealed abnormally thin dermis, markedly reduced amounts of dermal collagen bundles, with loosely orientation and abnormally large spaces between deep dermal fibers. WFFS is a novel genetic disease in horses and should be considered in cases of abortion, stillbirth, skin lesions and malformations of the skin in neonatal foals. Genetic testing of suspicious cases will contribute to evaluate the frequency of occurrence of clinical WFFS cases and its relevance for the horse population.

  15. Autosomal dominant SCA5 and autosomal recessive infantile SCA are allelic conditions resulting from SPTBN2 mutations.

    Science.gov (United States)

    Elsayed, Solaf M; Heller, Raoul; Thoenes, Michaela; Zaki, Maha S; Swan, Daniel; Elsobky, Ezzat; Zühlke, Christine; Ebermann, Inga; Nürnberg, Gudrun; Nürnberg, Peter; Bolz, Hanno J

    2014-02-01

    Although many genes have been identified for the autosomal recessive cerebellar ataxias (ARCAs), several patients are unlinked to the respective loci, suggesting further genetic heterogeneity. We combined homozygosity mapping and exome sequencing in a consanguineous Egyptian family with congenital ARCA, mental retardation and pyramidal signs. A homozygous 5-bp deletion in SPTBN2, the gene whose in-frame mutations cause autosomal dominant spinocerebellar ataxia type 5, was shown to segregate with ataxia in the family. Our findings are compatible with the concept of truncating SPTBN2 mutations acting recessively, which is supported by disease expression in homozygous, but not heterozygous, knockout mice, ataxia in Beagle dogs with a homozygous frameshift mutation and, very recently, a homozygous SPTBN2 nonsense mutation underlying infantile ataxia and psychomotor delay in a human family. As there was no evidence for mutations in 23 additional consanguineous families, SPTBN2-related ARCA is probably rare.

  16. Three novel mutations in the CFTR gene identified in Galician patients.

    Science.gov (United States)

    Rana-Díez, P; Colón, C; Alonso-Fernández, J R; Solar, A; Barros-Tizón, J C; Barros-Casas, D; Sirvent, J; Carracedo, A; Barros, F

    2008-11-01

    We report three novel CFTR missense mutations detected in Spanish patients from Galicia (North West of Spain). In the first case, a patient homozygous for a novel S1045Y mutation died due to pulmonary problems. In the other two cases, both heterozygous for novel mutations combined with the F508del mutation, clinical symptoms were different depending on the mutation, detected as M595I and A107V.

  17. Women with homozygous AT deficiency type II heparin-binding site (HBS) are at high risk of pregnancy loss and pregnancy complications.

    Science.gov (United States)

    Kraft, Julia; Sunder-Plassmann, Raute; Mannhalter, Christine; Quehenberger, Peter; Tews, Gernot; Langer, Martin; Pabinger, Ingrid

    2017-06-01

    Data regarding outcome and therapy of pregnancies in patients with homozygous antithrombin (AT) deficiency are very rare. We conducted a retrospective, descriptive investigation with emphasis on the obstetric history of eight women with homozygous AT deficiency heparin-binding site (HBS), who had at least one pregnancy. The aim of the study was to get a better insight into the outcome and identify suitable management procedures of pregnancy in this rare disease. All patients suffered from homozygous AT deficiency caused by the mutation c.391C>T p.Leu131Phe in the AT gene (SERPINC1). The women reported in total 23 pregnancies; one pregnancy was excluded because of induced abortion. We found that only seven out of the 22 analyzed pregnancies ended with a live infant, all of them were born preterm. Among the 15 negative outcomes, seven were early pregnancy losses and eight were intrauterine fetal deaths. We found no clear association between treatment protocols and outcome. Eight pregnancies were not treated at all; all of them ended with pregnancy loss. We conclude that homozygous AT deficiency HBS, a form of severe thrombophilia, is associated with high risk of pregnancy loss and preterm delivery. Rigorous anticoagulation and/or replacement of AT during pregnancy may improve the outcome.

  18. Inactivation of rabies virus.

    Science.gov (United States)

    Wu, Guanghui; Selden, David; Fooks, Anthony R; Banyard, Ashley

    2017-05-01

    Rabies virus is a notifiable pathogen that must be handled in high containment facilities where national and international guidelines apply. For the effective inactivation of rabies virus, a number of reagents were tested. Virkon S (1%) solution caused more than 4log reduction of rabies virus in culture medium supplemented with 10% foetal calf serum within 1min. Isopropyl alcohol (70%) treatment resulted in >3log reduction of rabies virus within 20s when applied at a ratio of 19:1, making it a suitable agent for surface decontamination whereas 70% ethanol was ineffective. Rabies virus (from 102.33 to 103ffu/ml) was also inactivated when cell cultures were fixed with 3% or 4% paraformaldehyde for 30min. Regardless of inactivation procedure, when taking inactivated virus preparations out of a biological containment envelope, proof of inocuity must be demonstrated to cover any possible error/deviation from procedure. Crown Copyright © 2017. Published by Elsevier B.V. All rights reserved.

  19. A novel homozygous truncating GNAT1 mutation implicated in retinal degeneration.

    LENUS (Irish Health Repository)

    Carrigan, Matthew

    2016-04-01

    The GNAT1 gene encodes the α subunit of the rod transducin protein, a key element in the rod phototransduction cascade. Variants in GNAT1 have been implicated in stationary night-blindness in the past, but unlike other proteins in the same pathway, it has not previously been implicated in retinitis pigmentosa.

  20. A novel homozygous nonsense mutation in CABP4 causes congenital cone-rod synaptic disorder.

    NARCIS (Netherlands)

    Littink, K.W.; Genderen, M. van; Collin, R.W.J.; Roosing, S.; Brouwer, A.P.M. de; Riemslag, F.C.; Venselaar, H.; Thiadens, A.A.H.J.; Hoyng, C.B.; Rohrschneider, K.; Hollander, A.I. den; Cremers, F.P.M.; Born, L.I. van den

    2009-01-01

    PURPOSE: The purpose of this study was to identify the causative gene defect in two siblings with an uncharacterized cone-rod dysfunction and to describe the clinical characteristics. METHODS: Genome-wide homozygosity mapping, with a 250K SNP-array followed by a search for candidate genes, was

  1. ABCD syndrome is caused by a homozygous mutation in the EDNRB gene

    NARCIS (Netherlands)

    Verheij, JBGM; Kunze, J; Osinga, J; van Essen, AJ; Hofstra, RMW

    2002-01-01

    ABCD syndrome is an autosomal recessive syndrome characterized by albinism, black lock, cell migration disorder of the neurocytes of the gut (Hirschsprung disease [HSCR]), and deafness. This phenotype clearly overlaps with the features of the Shah-Waardenburg syndrome, comprising sensorineural

  2. A homozygous mutation in the luteinizing hormone receptor causes partial Leydig cell hypopla phenotype

    NARCIS (Netherlands)

    J.W.M. Martens (John); M. Verhoef-Post (Miriam); N. Abelin; M. Ezabella; S.P. Toledo (Rodrigo); H.G. Brunner (Han); A.P.N. Themmen (Axel)

    1998-01-01

    textabstractLeydig cell hypoplasia (LCH) is characterized by a decreased response of the Leydig cells to LH. As a result, patients with this syndrome display aberrant male development ranging from complete pseudohermaphroditism to males with micropenis but with otherwise normal sex

  3. New TFR2 mutations in young Italian patients with hemochromatosis.

    Science.gov (United States)

    Biasiotto, Giorgio; Camaschella, Clara; Forni, Gian Luca; Polotti, Anna; Zecchina, Gabriella; Arosio, Paolo

    2008-02-01

    This work describes the identification of two subjects with young-age iron overload carrying new causative mutations in transferrin receptor-2 gene. One was compound heterozygous (Asn411del/Ala444Thr) and the second was homozygous for a mutation affecting RNA splicing (IVS17+5636G>A). Another mutation (His33Asn) and a polymorphism were found in a group of 50 controls.

  4. Transmission of atypical scrapie to homozygous ARQ sheep.

    Science.gov (United States)

    Okada, Hiroyuki; Miyazawa, Kohtaro; Imamura, Morikazu; Iwamaru, Yoshifumi; Masujin, Kentaro; Matsuura, Yuichi; Yokoyama, Takashi

    2016-11-01

    Two Cheviot ewes homozygous for the A136L141R154Q171 (AL141RQ) prion protein (PrP) genotype were exposed intracerebrally to brain pools prepared using four field cases of atypical scrapie from the United Kingdom. Animals were clinically normal until the end of the experiment, when they were culled 7 years post-inoculation. Limited accumulation of disease-associated PrP (PrP(Sc)) was observed in the cerebellar molecular layer by immunohistochemistry, but not by western blot or enzyme-linked immunosorbent assay. In addition, PrP(Sc) was partially localized in astrocytes and microglia, suggesting that these cells have a role in PrP(Sc) processing, degradation or both. Our results indicate that atypical scrapie is transmissible to AL141RQ sheep, but these animals act as clinically silent carriers with long incubation times.

  5. Modification of C-type inactivating Shaker potassium channels by chloramine-T.

    Science.gov (United States)

    Schlief, T; Schönherr, R; Heinemann, S H

    1996-02-01

    Shaker potassium channels undergo a slow C-type inactivation which can be hastened dramatically by single-point mutations in or near the pore region. We found that the oxidizing agent chloramine-T (Chl-T) causes an irreversible loss of current for those mutants which show C-type inactivation. For several mutants at position T449, which show a wide spectrum of inactivation time constants, the time constant of current rundown induced by Chl-T correlated with the speed of inactivation. Rundown was accelerated when the channels were in the inactivated state but rundown also occurred when channels were not opened or inactivated. Apparently, only those channels which can undergo C-type inactivation are accessible to Chl-T. In order to gain information about the target amino-acid residue for the action of Chl-T and the structural rearrangements occurring during C-type inactivation, several mutant channel proteins were compared with respect to their response to Chl-T. Since Chl-T can oxidize cysteine and methionine residues, we mutated the possible targets in and close to the pore region, namely C462 to A, and M440 and M448 to I. While the residues M440 and C462 were not important for channel rundown, mutation of M448 to I made the channels more resistant to Chl-T by about one order of magnitude. While inactivation was accelerated upon application of Chl-T in most mutants, mutation of M448 to I abolished this effect on the time course of inactivation, indicating that M448 is one of the target residues for Chl-T.

  6. An Amish founder mutation disrupts a PI(3)P-WHAMM-Arp2/3 complex-driven autophagosomal remodeling pathway.

    Science.gov (United States)

    Mathiowetz, Alyssa J; Baple, Emma; Russo, Ashley J; Coulter, Alyssa M; Carrano, Eric; Brown, Judith D; Jinks, Robert N; Crosby, Andrew H; Campellone, Kenneth G

    2017-09-15

    Actin nucleation factors function to organize, shape, and move membrane-bound organelles, yet they remain poorly defined in relation to disease. Galloway-Mowat syndrome (GMS) is an inherited disorder characterized by microcephaly and nephrosis resulting from mutations in the WDR73 gene. This core clinical phenotype appears frequently in the Amish, where virtually all affected individuals harbor homozygous founder mutations in WDR73 as well as the closely linked WHAMM gene, which encodes a nucleation factor. Here we show that patient cells with both mutations exhibit cytoskeletal irregularities and severe defects in autophagy. Reintroduction of wild-type WHAMM restored autophagosomal biogenesis to patient cells, while inactivation of WHAMM in healthy cell lines inhibited lipidation of the autophagosomal protein LC3 and clearance of ubiquitinated protein aggregates. Normal WHAMM function involved binding to the phospholipid PI(3)P and promoting actin nucleation at nascent autophagosomes. These results reveal a cytoskeletal pathway controlling autophagosomal remodeling and illustrate several molecular processes that are perturbed in Amish GMS patients. © 2017 Mathiowetz, Baple, et al. This article is distributed by The American Society for Cell Biology under license from the author(s). Two months after publication it is available to the public under an Attribution–Noncommercial–Share Alike 3.0 Unported Creative Commons License (http://creativecommons.org/licenses/by-nc-sa/3.0).

  7. An Amish founder mutation disrupts a PI(3)P-WHAMM-Arp2/3 complex–driven autophagosomal remodeling pathway

    Science.gov (United States)

    Mathiowetz, Alyssa J.; Baple, Emma; Russo, Ashley J.; Coulter, Alyssa M.; Carrano, Eric; Brown, Judith D.; Jinks, Robert N.; Crosby, Andrew H.; Campellone, Kenneth G.

    2017-01-01

    Actin nucleation factors function to organize, shape, and move membrane-bound organelles, yet they remain poorly defined in relation to disease. Galloway-Mowat syndrome (GMS) is an inherited disorder characterized by microcephaly and nephrosis resulting from mutations in the WDR73 gene. This core clinical phenotype appears frequently in the Amish, where virtually all affected individuals harbor homozygous founder mutations in WDR73 as well as the closely linked WHAMM gene, which encodes a nucleation factor. Here we show that patient cells with both mutations exhibit cytoskeletal irregularities and severe defects in autophagy. Reintroduction of wild-type WHAMM restored autophagosomal biogenesis to patient cells, while inactivation of WHAMM in healthy cell lines inhibited lipidation of the autophagosomal protein LC3 and clearance of ubiquitinated protein aggregates. Normal WHAMM function involved binding to the phospholipid PI(3)P and promoting actin nucleation at nascent autophagosomes. These results reveal a cytoskeletal pathway controlling autophagosomal remodeling and illustrate several molecular processes that are perturbed in Amish GMS patients. PMID:28720660

  8. Rescue of progeria in trichothiodystrophy by homozygous lethal Xpd alleles.

    Directory of Open Access Journals (Sweden)

    Jaan-Olle Andressoo

    2006-10-01

    Full Text Available Although compound heterozygosity, or the presence of two different mutant alleles of the same gene, is common in human recessive disease, its potential to impact disease outcome has not been well documented. This is most likely because of the inherent difficulty in distinguishing specific biallelic effects from differences in environment or genetic background. We addressed the potential of different recessive alleles to contribute to the enigmatic pleiotropy associated with XPD recessive disorders in compound heterozygous mouse models. Alterations in this essential helicase, with functions in both DNA repair and basal transcription, result in diverse pathologies ranging from elevated UV sensitivity and cancer predisposition to accelerated segmental progeria. We report a variety of biallelic effects on organismal phenotype attributable to combinations of recessive Xpd alleles, including the following: (i the ability of homozygous lethal Xpd alleles to ameliorate a variety of disease symptoms when their essential basal transcription function is supplied by a different disease-causing allele, (ii differential developmental and tissue-specific functions of distinct Xpd allele products, and (iii interallelic complementation, a phenomenon rarely reported at clinically relevant loci in mammals. Our data suggest a re-evaluation of the contribution of "null" alleles to XPD disorders and highlight the potential of combinations of recessive alleles to affect both normal and pathological phenotypic plasticity in mammals.

  9. ROS-induced near-homozygous genomes in thyroid cancer.

    Science.gov (United States)

    Corver, Willem; Demmers, Joris; Oosting, Jan; Sahraeian, Shima; Boot, Arnoud; Ruano, Dina; van Wezel, Tom; Morreau, Hans

    2017-10-24

    A near-homozygous genome (NHG) is especially seen in a subset of follicular thyroid of the oncocytic type (FTC-OV). A NHG was also observed in the metabolically relatively quiescent cell lines XTC.UC1, a model for FTC-OV, and in FTC-133, -236 and -238, the latter three derived from one single patient with follicular thyroid cancer. FTC-236 subclones showed subtle whole-chromosome differences indicative of sustained reciprocal mitotic missegregations. Reactive oxygen species (ROS) scavenger experiments reduced the number of chromosomal missegregations in XTC.UC1 and FTC-236 while pCHK2 was down-regulated in these cells. Treatment with Antimycin A increased ROS indicated by enhanced MitoSOX Red and pCHK2 fluorescence in metaphase cells. In a selected set of oncocytic follicular thyroid tumors increasing numbers of whole-chromosome losses were observed towards an aggressive phenotype, but with retention of chromosome 7. Together, ROS activates CHK2 and links to the stepwise loss of whole-chromosomes during tumor progression in these lesions. We postulate that sequential loss of whole-chromosomes is a dominant driver of the oncogenesis of a subset of follicular thyroid tumors.

  10. Computational imaging analysis of fibrin matrices with the inclusion of erythrocytes from homozygous SS blood reveals agglomerated and amorphous structures.

    Science.gov (United States)

    Averett, Rodney D; Norton, David G; Fan, Natalie K; Platt, Manu O

    2017-01-01

    Sickle cell disease is a single point mutation disease that is known to alter the coagulation system, leading to hypercoagulable plasma conditions. These hypercoagulable conditions can lead to complications in the vasculature, caused by fibrin clots that form undesirably. There is a need to understand the morphology and structure of fibrin clots from patients with sickle cell disease, as this could lead to further discovery of treatments and life-saving therapies. In this work, a computational imaging analysis method is presented to evaluate fibrin agglomeration in the presence of erythrocytes (RBCs) homozygous for the sickle cell mutation (SS). Numerical algorithms were used to determine agglomeration of fibrin fibers within a matrix with SS RBCs to test the hypothesis that fibrin matrices with the inclusion of SS RBCs possess a more agglomerated structure than native fibrin matrices with AA RBCs. The numerical results showed that fibrin structures with SS RBCs displayed an overall higher degree of agglomeration as compared to native fibrin structures. The computational algorithm was also used to evaluate fibrin fiber overlap (aggregation) and anisotropy (orientation) in normal fibrin matrices compared to fibrin matrices polymerized around SS RBCs; however, there was no statistical difference. Ultrasound measurements of stiffness revealed rigid RBCs in the case of samples derived from homozygous SS blood, and densely evolving matrices, when compared to normal fibrin with the inclusion of AA RBCs. An agglomeration model is suggested to quantify the fibrin aggregation/clustering near RBCs for both normal fibrin matrices and for the altered structures. The results of this work are important in the sense that the understanding of aggregation and morphology in fibrin clots with incorporation of RBCs from persons living with sickle cell anemia may elucidate the complexities of comorbidities and other disease complications.

  11. Thermal Inactivation of Viruses

    Science.gov (United States)

    1977-10-01

    S) VIKU3FS THERMAL RESISTANCE FOODS FLUIDS FOOD PROCESSING FOOD PRESERVATION CONTAMINATION HEAT VIRAL NUCLEIC ACIDS ao’.AjUsTNACT (Conilnum...an rm**— •**» It nmc +nmy m>d Id+atttr by M«o* fmbm) A review of the literature pertaining to thermal inactivation of virus in fluid media» fluid...vacuum packaged in cans or in flexible pouches , frozen to ca. -40 C, and irradiated within a temperature range of -40 C to -8 C to obtain the

  12. Co-inheritance of novel ATRX gene mutation and globin (α & β) gene mutations in transfusion dependent beta-thalassemia patients.

    Science.gov (United States)

    Al-Nafie, Awatif N; Borgio, J Francis; AbdulAzeez, Sayed; Al-Suliman, Ahmed M; Qaw, Fuad S; Naserullah, Zaki A; Al-Jarrash, Sana; Al-Madan, Mohammed S; Al-Ali, Rudaynah A; AlKhalifah, Mohammed A; Al-Muhanna, Fahad; Steinberg, Martin H; Al-Ali, Amein K

    2015-06-01

    α-Thalassemia X-linked mental retardation syndrome is a rare inherited intellectual disability disorder due to mutations in the ATRX gene. In our previous study of the prevalence of β-thalassemia mutations in the Eastern Province of Saudi Arabia, we confirmed the widespread coinheritance of α-thalassemia mutation. Some of these subjects have a family history of mental retardation, the cause of which is unknown. Therefore, we investigated the presence or absence of mutations in the ATRX gene in these patients. Three exons of the ATRX gene and their flanking regions were directly sequenced. Only four female transfusion dependent β-thalassemia patients were found to be carriers of a novel mutation in the ATRX gene. Two of the ATRX gene mutations, c.623delA and c.848T>C were present in patients homozygous for IVS I-5(G→C) and homozygous for Cd39(C → T) β-thalassemia mutation, respectively. While the other two that were located in the intronic region (flanking regions), were present in patients homozygous for Cd39(C → T) β-thalassemia mutation. The two subjects with the mutations in the coding region had family members with mental retardation, which suggests that the novel frame shift mutation and the missense mutation at coding region of ATRX gene are involved in ATRX syndrome. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Production of Fully Homozygous Genotypes from Various Edible Alliums

    Directory of Open Access Journals (Sweden)

    A. R. ALAN

    2014-06-01

    Full Text Available Allium is a very large genus containing over 700 distinct species including the various edible onions, garlics, chives, and leeks. About a dozen of the species are economically important as crops or garden vegetables where as many others are cultivated as ornamental plants. Allium breeding programs generally take very long time with low success due to problems such as long life cycle, sterility, polyploidy, high levels of heterozygosity. Development of inbreed lines is a very difficult process due to severe inbreeding depression. Doubled haploid (DH techniques can be utilized to obtain fully homozygous Allium materials. In Alliums, gynogenesis is the major technique used to produce haploid and DH plants from unfertilized female gamets with reduced chromosome number. We are in the process of developing gynogenesis induction protocols for several edible Allium species. We showed that gynogenic embryos can be obtained from a wide range of Allium materials. About half of the gynogenic embryos continue to grow and become plantlets. In general, gynogenic plantlets are green, but some of them show chlorophyll abnomalities. Results obtained from flow cytometric analysis of nuclei isolated from gynogenic materials indicate that majority of the gynogenic Allium materials are haploid and DH plants. DH onion lines developed in our program are generally vigorous plants with high levels of fecundity. The seeds obtained from DH onions show high germination. Plants of DH onion lines grow uniformly and produce bulbs very uniform in size, shape, color and quality features. These DH lines are excellent inbreds to be used as male parents in the production of F1 hybrid onion lines. Success obtained in DH onion materials indicates that a similar approach can be applied in the breeding programs of other important Alliums.

  14. DFNB1 Non-syndromic Hearing Impairment: Diversity of Mutations and Associated Phenotypes

    Directory of Open Access Journals (Sweden)

    Francisco J. del Castillo

    2017-12-01

    Full Text Available The inner ear is a very complex sensory organ whose development and function depend on finely balanced interactions among diverse cell types. The many different kinds of inner ear supporting cells play the essential roles of providing physical and physiological support to sensory hair cells and of maintaining cochlear homeostasis. Appropriately enough, the gene most commonly mutated among subjects with hereditary hearing impairment (HI, GJB2, encodes the connexin-26 (Cx26 gap-junction channel protein that underlies both intercellular communication among supporting cells and homeostasis of the cochlear fluids, endolymph and perilymph. GJB2 lies at the DFNB1 locus on 13q12. The specific kind of HI associated with this locus is caused by recessively-inherited mutations that inactivate the two alleles of the GJB2 gene, either in homozygous or compound heterozygous states. We describe the many diverse classes of genetic alterations that result in DFNB1 HI, such as large deletions that either destroy the GJB2 gene or remove a regulatory element essential for GJB2 expression, point mutations that interfere with promoter function or splicing, and small insertions or deletions and nucleotide substitutions that target the GJB2 coding sequence. We focus on how these alterations disrupt GJB2 and Cx26 functions and on their different effects on cochlear development and physiology. We finally discuss the diversity of clinical features of DFNB1 HI as regards severity, age of onset, inner ear malformations and vestibular dysfunction, highlighting the areas where future research should be concentrated.

  15. Hypomyelinating Leukodystrophy due to HSPD1 Mutations

    DEFF Research Database (Denmark)

    Kusk, Maria Schioldan; Damgaard, Bodil; Risom, Lotte

    2016-01-01

    The hypomyelinating leukodystrophies (HMLs) encompass the X-linked Pelizaeus-Merzbacher disease (PMD) caused by PLP1 mutations and known as the classical form of HML as well as Pelizaeus-Merzbacher-like disease (PMLD) (Online Mendelian Inheritance in Man [OMIM] 608804 and OMIM 260600) due to GJC2...... mutations. In addition, mutations in at least 10 other genes are known to cause HMLs. In 2008, an Israeli family with clinical and neuroimaging findings similar to those found in PMD was reported. The patients were found to have a homozygous missense mutation in HSPD1, encoding the mitochondrial heat......-shock protein 60 (Hsp60), and the disorder was defined as the autosomal recessive mitochondrial Hsp60 chaperonopathy (MitCHAP-60) disease. We here report the first case of this severe neurodegenerative disease since it was first described. Given the fact that the families carried the same mutation our patient...

  16. A novel missense mutation in SUCLG1 associated with mitochondrial DNA depletion, encephalomyopathic form, with methylmalonic aciduria

    DEFF Research Database (Denmark)

    Østergaard, Elsebet; Schwartz, Marianne; Batbayli, Mustafa

    2010-01-01

    Mitochondrial DNA depletion, encephalomyopathic form, with methylmalonic aciduria is associated with mutations in SUCLA2, the gene encoding a beta subunit of succinate-CoA ligase, where 17 patients have been reported. Mutations in SUCLG1, encoding the alpha subunit of the enzyme, have been report...... in only one family, where a homozygous 2 bp deletion was associated with fatal infantile lactic acidosis. We here report a patient with a novel homozygous missense mutation in SUCLG1, whose phenotype is similar to that of patients with SUCLA2 mutations....

  17. A novel mutation in the leptin gene (W121X in an Egyptian family

    Directory of Open Access Journals (Sweden)

    Inas Mazen

    2014-01-01

    Full Text Available Congenital leptin deficiency is a rare recessively inherited condition due to homozygous mutations in the LEP gene. To date, only nine mutations have been identified in the LEP gene (p.L72S, p.N103K, p.R105W, p.H118L, p.S141C, c.104_106delTCA, c.135del3bp, c.398delG and c.481_482delCT. In this study we present a novel homozygous nonsense mutation (W121X in LEP in a twelve year old obese male and his severely obese sister. As this disorder is treatable with recombinant leptin, it is intriguing to report a novel homozygous nonsense mutation in LEP in two obese children of consanguineous parents. These patients showed features in accordance with leptin deficiency.

  18. 'North Sea' progressive myoclonus epilepsy: phenotype of subjects with GOSR2 mutation

    NARCIS (Netherlands)

    Boisse Lomax, L.; Bayly, M.A.; Hjalgrim, H.; Moller, R.S.; Vlaar, A.M.M.; Aaberg, K.M.; Marquardt, I.; Gandolfo, L.C.; Willemsen, M.A.; Kamsteeg, E.J.; O'Sullivan, J.D.; Korenke, G.C.; Bloem, B.R.; Coo, I.F. de; Verhagen, J.M.A.; Said, I.; Prescott, T.; Stray-Pedersen, A.; Rasmussen, M.; Vears, D.F.; Lehesjoki, A.E.; Corbett, M.A.; Bahlo, M.; Gecz, J.; Dibbens, L.M.; Berkovic, S.F.

    2013-01-01

    We previously identified a homozygous mutation in the Golgi SNAP receptor complex 2 gene (GOSR2) in six patients with progressive myoclonus epilepsy. To define the syndrome better we analysed the clinical and electrophysiological phenotype in 12 patients with GOSR2 mutations, including six new

  19. Biological insights into BRAF(V600) mutations in melanoma patient

    DEFF Research Database (Denmark)

    Improta, Giuseppina; Pelosi, Giuseppe; Tamborini, Elena

    2013-01-01

    Some experimental evidence indicates that uncommon BRAF mutations consisting in the substitution of 2 adjacent nucleotides within codon 600 are in a cis configuration and associate with BRAF gene amplification. These findings suggest that BRAF(V600) mutations are unlikely to occur as homozygous a...... alterations in clinical melanoma samples, with gene amplification perhaps contributing to mask the heterozygous state....

  20. 574-586 Mutations in PCBD1 cause hypomagnesemia and renal magnesium wasting

    NARCIS (Netherlands)

    S. Ferrè (Silvia); J.H.F. de Baaij (Jeroen H.); P. Ferreira (Patrick); R. Germann (Roger); J.B.C. de Klerk (Johannes); A.P.M. Lavrijsen (Adriana); F. van Zeeland (Femke); H. Venselaar (Hanka); L.A.J. Kluijtmans (Leo A.); J.G. Hoenderop (Joost); R.J.M. Bindels (René)

    2014-01-01

    textabstractMutations in PCBD1 are causative for transient neonatal hyperphenylalaninemia and primapterinuria (HPABH4D). Until now, HPABH4D has been regarded as a transient and benign neonatal syndrome without complications in adulthood. In our study of three adult patients with homozygous mutations

  1. A newly described bovine type 2 scurs syndrome segregates with a frame-shift mutation in TWIST1.

    Directory of Open Access Journals (Sweden)

    Aurélien Capitan

    Full Text Available The developmental pathways involved in horn development are complex and still poorly understood. Here we report the description of a new dominant inherited syndrome in the bovine Charolais breed that we have named type 2 scurs. Clinical examination revealed that, despite a strong phenotypic variability, all affected individuals show both horn abnormalities similar to classical scurs phenotype and skull interfrontal suture synostosis. Based on a genome-wide linkage analysis using Illumina BovineSNP50 BeadChip genotyping data from 57 half-sib and full-sib progeny, this locus was mapped to a 1.7 Mb interval on bovine chromosome 4. Within this region, the TWIST1 gene encoding a transcription factor was considered as a strong candidate gene since its haploinsufficiency is responsible for the human Saethre-Chotzen syndrome, characterized by skull coronal suture synostosis. Sequencing of the TWIST1 gene identified a c.148_157dup (p.A56RfsX87 frame-shift mutation predicted to completely inactivate this gene. Genotyping 17 scurred and 20 horned founders of our pedigree as well as 48 unrelated horned controls revealed a perfect association between this mutation and the type 2 scurs phenotype. Subsequent genotyping of 32 individuals born from heterozygous parents showed that homozygous mutated progeny are completely absent, which is consistent with the embryonic lethality reported in Drosophila and mouse suffering from TWIST1 complete insufficiency. Finally, data from previous studies on model species and a fine description of type 2 scurs symptoms allowed us to propose different mechanisms to explain the features of this syndrome. In conclusion, this first report on the identification of a potential causal mutation affecting horn development in cattle offers a unique opportunity to better understand horn ontogenesis.

  2. A Newly Described Bovine Type 2 Scurs Syndrome Segregates with a Frame-Shift Mutation in TWIST1

    Science.gov (United States)

    Capitan, Aurélien; Grohs, Cécile; Weiss, Bernard; Rossignol, Marie-Noëlle; Reversé, Patrick; Eggen, André

    2011-01-01

    The developmental pathways involved in horn development are complex and still poorly understood. Here we report the description of a new dominant inherited syndrome in the bovine Charolais breed that we have named type 2 scurs. Clinical examination revealed that, despite a strong phenotypic variability, all affected individuals show both horn abnormalities similar to classical scurs phenotype and skull interfrontal suture synostosis. Based on a genome-wide linkage analysis using Illumina BovineSNP50 BeadChip genotyping data from 57 half-sib and full-sib progeny, this locus was mapped to a 1.7 Mb interval on bovine chromosome 4. Within this region, the TWIST1 gene encoding a transcription factor was considered as a strong candidate gene since its haploinsufficiency is responsible for the human Saethre-Chotzen syndrome, characterized by skull coronal suture synostosis. Sequencing of the TWIST1 gene identified a c.148_157dup (p.A56RfsX87) frame-shift mutation predicted to completely inactivate this gene. Genotyping 17 scurred and 20 horned founders of our pedigree as well as 48 unrelated horned controls revealed a perfect association between this mutation and the type 2 scurs phenotype. Subsequent genotyping of 32 individuals born from heterozygous parents showed that homozygous mutated progeny are completely absent, which is consistent with the embryonic lethality reported in Drosophila and mouse suffering from TWIST1 complete insufficiency. Finally, data from previous studies on model species and a fine description of type 2 scurs symptoms allowed us to propose different mechanisms to explain the features of this syndrome. In conclusion, this first report on the identification of a potential causal mutation affecting horn development in cattle offers a unique opportunity to better understand horn ontogenesis. PMID:21814570

  3. Autosomal recessive hypercholesterolemia (ARH) and homozygous familial hypercholesterolemia (FH): a phenotypic comparison.

    Science.gov (United States)

    Pisciotta, Livia; Priore Oliva, Claudio; Pes, Giovanni Mario; Di Scala, Lilla; Bellocchio, Antonella; Fresa, Raffaele; Cantafora, Alfredo; Arca, Marcello; Calandra, Sebastiano; Bertolini, Stefano

    2006-10-01

    Autosomal recessive hypercholesterolemia (ARH) is a rare disorder, due to complete loss of function of an adaptor protein (ARH protein) required for receptor-mediated hepatic uptake of LDL. ARH is a phenocopy of homozygous familial hypercholesterolemia (HoFH) due to mutations in LDL receptor (LDLR) gene; however, previous studies suggested that ARH phenotype is less severe than that of HoFH. To test this hypothesis we compared 42 HoFH and 42 ARH patients. LDLR and ARH genes were analysed by Southern blotting and sequencing. LDLR activity was measured in cultured fibroblasts. In ARH plasma LDL cholestrol (LDL-C) level (14.25+/-2.29 mmol/L) was lower than in receptor-negative HoFH (21.38+/-3.56 mmol/L) but similar to that found in receptor-defective HoFH (15.52+/-2.39 mmol/L). The risk of coronary artery disease (CAD) was 9-fold lower in ARH patients. No ARH patients

  4. Cell autonomy of the mouse claw paw mutation.

    NARCIS (Netherlands)

    A. Darbas (Aysel); M.M. Jaegle (Martine); E.T. Walbeehm (Erik); H. van den Burg (Hans); L.A.M. Broos (Ludo); M. Uyl (Matthijs); P. Visser (Pim); F.G. Grosveld (Frank); D.N. Meijer (Dies); M.J.F. Driegen (Siska)

    2004-01-01

    textabstractMice homozygous for the autosomal recessive mutation claw paw (clp) are characterized by limb posture abnormalities and congenital hypomyelination, with delayed onset of myelination of the peripheral nervous system but not the central nervous system. Although this combination of limb and

  5. Malignant transformation of neurofibromas in neurofibromatosis 1 is associated with CDKN2A/p16 inactivation

    DEFF Research Database (Denmark)

    Nielsen, G P; Stemmer-Rachamimov, A O; Ino, Y

    1999-01-01

    of the benign tumors had CDKN2A/p16 deletions, whereas three of six MPNSTs appeared to have homozygous CDKN2A/p16 deletions. Methylation analysis and mutation analysis of CDKN2A/p16 in MPNSTs did not reveal any abnormalities. These results show that malignant transformation of NF is associated with loss of p16...

  6. Inactivation of Microorganisms

    Science.gov (United States)

    Alzamora, Stella Maris; Guerrero, Sandra N.; Schenk, Marcela; Raffellini, Silvia; López-Malo, Aurelio

    Minimal processing techniques for food preservation allow better retention of product flavor, texture, color, and nutrient content than comparable conventional treatments. A wide range of novel alternative physical factors have been intensely investigated in the last two decades. These physical factors can cause inactivation of microorganisms at ambient or sublethal temperatures (e.g., high hydrostatic pressure, pulsed electric fields, ultrasound, pulsed light, and ultraviolet light). These technologies have been reported to reduce microorganism population in foods while avoiding the deleterious effects of severe heating on quality. Among technologies, high-energy ultrasound (i.e., intensities higher than 1 W/cm2, frequencies between 18 and 100 kHz) has attracted considerable interest for food preservation applications (Mason et al., 1996; Povey and Mason, 1998).

  7. Congenital myopathy is caused by mutation of HACD1

    OpenAIRE

    Muhammad, Emad; Reish, Orit; Ohno, Yusuke; Scheetz, Todd; DeLuca, Adam; Searby, Charles; Regev, Miriam; Benyamini, Lilach; Fellig, Yakov; Kihara, Akio; Sheffield, Val C.; Parvari, Ruti

    2013-01-01

    Congenital myopathies are heterogeneous inherited diseases of muscle characterized by a range of distinctive histologic abnormalities. We have studied a consanguineous family with congenital myopathy. Genome-wide linkage analysis and whole-exome sequencing identified a homozygous non-sense mutation in 3-hydroxyacyl-CoA dehydratase 1 (HACD1) in affected individuals. The mutation results in non-sense mediated decay of the HACD1 mRNA to 31% of control levels in patient muscle and completely abro...

  8. Prospects for a Novel Ultrashort Pulsed Laser Technology for Pathogen Inactivation

    Science.gov (United States)

    2012-07-06

    that its length was about 850 nm and that it was in a zigzagged structure indicated that these zigzagged structures were naked viral genomic DNAs...treatment has been shown to inactivate a variety of viruses including HIV, Influenza virus, Human Papillomavirus ( HPV ), Murine Noroviruses, Hepatitis A...and bacterial pathogens regardless of their structural composition or mutation status. For the inactivation of a virus, the USP laser method excites

  9. FKRP mutations, including a founder mutation, cause phenotype variability in Chinese patients with dystroglycanopathies.

    Science.gov (United States)

    Fu, Xiaona; Yang, Haipo; Wei, Cuijie; Jiao, Hui; Wang, Shuo; Yang, Yanling; Han, Chunxi; Wu, Xiru; Xiong, Hui

    2016-12-01

    Mutations in the fukutin-related protein (FKRP) gene have been associated with dystroglycanopathies, which are common in Europe but rare in Asia. Our study aimed to retrospectively analyze and characterize the clinical, myopathological and genetic features of 12 Chinese patients with FKRP mutations. Three patients were diagnosed with congenital muscular dystrophy type 1C (MDC1C) and nine patients were diagnosed with limb girdle muscular dystrophy type 2I (LGMD2I). Three muscle biopsy specimens had dystrophic changes and reduced glycosylated α-dystroglycan staining, and two showed reduced expression of laminin α2. Two known and 13 novel mutations were identified in our single center cohort. Interestingly, the c.545A>G mutation was found in eight of the nine LGMD2I patients as a founder mutation and this founder mutation in Chinese patients differs from the one seen in European patients. Moreover, patients homozygous for the c.545A>G mutation were clinically asymptomatic, a less severe phenotype than in compound heterozygous patients with the c.545A>G mutation. The 13 novel mutations of FKRP significantly expanded the mutation spectrum of MDC1C and LGMD2I, and the different founder mutations indicate the ethnic difference in FKRP mutations.

  10. The molecular landscape of ASPM mutations in primary microcephaly.

    Science.gov (United States)

    Nicholas, A K; Swanson, E A; Cox, J J; Karbani, G; Malik, S; Springell, K; Hampshire, D; Ahmed, M; Bond, J; Di Benedetto, D; Fichera, M; Romano, C; Dobyns, W B; Woods, C G

    2009-04-01

    Autosomal recessive primary microcephaly (MCPH) is a model disease to study human neurogenesis. In affected individuals the brain grows at a reduced rate during fetal life resulting in a small but structurally normal brain and mental retardation. The condition is genetically heterogeneous with mutations in ASPM being most commonly reported. We have examined this further by studying three cohorts of microcephalic children to extend both the phenotype and the mutation spectrum. Firstly, in 99 consecutively ascertained consanguineous families with a strict diagnosis of MCPH, 41 (41%) were homozygous at the MCPH5 locus and all but two families had mutations. Thus, 39% of consanguineous MCPH families had homozygous ASPM mutations. Secondly, in 27 non-consanguineous, predominantly Caucasian families with a strict diagnosis of MCPH, 11 (40%) had ASPM mutations. Thirdly, in 45 families with a less restricted phenotype including microcephaly and mental retardation, but regardless of other neurological features, only 3 (7%) had an ASPM mutation. This report contains 27 novel mutations and almost doubles the number of MCPH associated ASPM mutations known to 57. All but one of the mutations lead to the use of a premature termination codon, 23 were nonsense mutations, 28 deletions or insertions, 5 splicing, and 1 was a translocation. Seventeen of the 57 mutations were recurrent. There were no definitive missense mutations found nor was there any mutation/phenotype correlation. ASPM mutations were found in all ethnic groups studied. This study confirms that mutations in ASPM are the most common cause of MCPH, that ASPM mutations are restricted to individuals with an MCPH phenotype, and that ASPM testing in primary microcephaly is clinically useful.

  11. The spectrum of KIAA0196 variants, and characterization of a murine knockout: implications for the mutational mechanism in hereditary spastic paraplegia type SPG8.

    Science.gov (United States)

    Jahic, Amir; Khundadze, Mukhran; Jaenisch, Nadine; Schüle, Rebecca; Klimpe, Sven; Klebe, Stephan; Frahm, Christiane; Kassubek, Jan; Stevanin, Giovanni; Schöls, Ludger; Brice, Alexis; Hübner, Christian A; Beetz, Christian

    2015-11-16

    The hereditary spastic paraplegias (HSPs) are rare neurodegenerative gait disorders which are genetically highly heterogeneous. For each single form, eventual consideration of therapeutic strategies requires an understanding of the mechanism by which mutations confer pathogenicity. SPG8 is a dominantly inherited HSP, and associated with rather early onset and rapid progression. A total of nine mutations in KIAA0196, which encodes the WASH regulatory complex (SHRC) member strumpellin, have been reported in SPG8 patients so far. Based on biochemical and cell biological approaches, they have been suggested to act via loss of function-mediated haploinsufficiency. We generated a deletion-based knockout allele for E430025E21Rik, i.e. the murine homologue of KIAA0196. The consequences on mRNA and protein levels were analyzed by qPCR and Western-blotting, respectively. Motor performance was evaluated by the foot-base angle paradigm. Axon outgrowth and relevant organelle compartments were investigated in primary neuron cultures and primary fibroblast cultures, respectively. A homemade multiplex ligation-dependent probe amplification assay enabling identification of large inactivating KIAA0196 deletion alleles was applied to DNA from 240 HSP index patients. Homozygous but not heterozygous mice showed early embryonic lethality. No transcripts from the knockout allele were detected, and the previously suggested compensation by the wild-type allele upon heterozygosity was disproven. mRNA expression of genes encoding other SHRC members was unaltered, while there was evidence for reduced SHRC abundance at protein level. We did, however, neither observe HSP-related in vivo and ex vivo phenotypes, nor alterations affecting endosomal, lysosomal, or autophagic compartments. KIAA0196 copy number screening excluded large inactivating deletion mutations in HSP patients. The consequences of monoallelic KIAA0196/E430025E21Rik activation thus differ from those observed for dominant HSP

  12. Mutations Inactivating Herpes Simplex Virus 1 MicroRNA miR-H2 Do Not Detectably Increase ICP0 Gene Expression in Infected Cultured Cells or Mouse Trigeminal Ganglia.

    Science.gov (United States)

    Pan, Dongli; Pesola, Jean M; Li, Gang; McCarron, Seamus; Coen, Donald M

    2017-01-15

    Herpes simplex virus 1 (HSV-1) latency entails the repression of productive ("lytic") gene expression. An attractive hypothesis to explain some of this repression involves inhibition of the expression of ICP0, a lytic gene activator, by a viral microRNA, miR-H2, which is completely complementary to ICP0 mRNA. To test this hypothesis, we engineered mutations that disrupt miR-H2 without affecting ICP0 in HSV-1. The mutant virus exhibited drastically reduced expression of miR-H2 but showed wild-type levels of infectious virus production and no increase in ICP0 expression in lytically infected cells, which is consistent with the weak expression of miR-H2 relative to the level of ICP0 mRNA in that setting. Following corneal inoculation of mice, the mutant was not significantly different from wild-type virus in terms of infectious virus production in the trigeminal ganglia during acute infection, mouse mortality, or the rate of reactivation from explanted latently infected ganglia. Critically, the mutant was indistinguishable from wild-type virus for the expression of ICP0 and other lytic genes in acutely and latently infected mouse trigeminal ganglia. The latter result may be related to miR-H2 being less effective in inhibiting ICP0 expression in transfection assays than a host microRNA, miR-138, which has previously been shown to inhibit lytic gene expression in infected ganglia by targeting ICP0 mRNA. Additionally, transfected miR-138 reduced lytic gene expression in infected cells more effectively than miR-H2. While this study provides little support for the hypothesis that miR-H2 promotes latency by inhibiting ICP0 expression, the possibility remains that miR-H2 might target other genes during latency. Herpes simplex virus 1 (HSV-1), which causes a variety of diseases, can establish lifelong latent infections from which virus can reactivate to cause recurrent disease. Latency is the most biologically interesting and clinically vexing feature of the virus. Ever since

  13. CHM gene molecular analysis and X-chromosome inactivation pattern determination in two families with choroideremia.

    Science.gov (United States)

    Perez-Cano, Hector J; Garnica-Hayashi, Rosa E; Zenteno, Juan C

    2009-10-01

    Choroideremia is an X-linked recessive retinal dystrophy characterized by progressive loss of the photoreceptor, the retinal pigment epithelium, and the choriocapillaris layers which ultimately can result in blindness by the fifth decade of life. The disease is caused by mutations in the gene CHM, which encodes a protein involved in the regulation of intracellular vesicular traffic. Typically, hemizygous males are affected by the disease and female carriers are asymptomatic with only a diffuse mottled pattern of hyperpigmentation on funduscopy. Uncommon instances of fully affected females have been described previously and these cases are proposed to arise from an skewed Lyonization mechanism preferentially inactivating the X chromosome carrying the normal CHM allele. In this work, the clinical and molecular features of two Mexican families with choroideremia are described. A novel and a previously described CHM mutation were identified. X-chromosome inactivation assays were performed in a total of 12 heterozygous carriers from the two families. In an affected female from family A, a random X-inactivation pattern was demonstrated; on the other hand, in a female carrier from family B displaying a conspicuous pattern of pigment epithelium mottling at the peripheral retina, a skewed X-inactivation pattern was found. However, the X-chromosome preferentially inactivated in this female was the one carrying the mutated allele. Our results add to the genotypic spectrum in choroideremia and does not support a correlation between X-inactivation status and abnormal retinal phenotype in heterozygous female carriers from these two families.

  14. X inactivation in females with X-linked Charcot-Marie-Tooth disease.

    LENUS (Irish Health Repository)

    Murphy, Sinéad M

    2012-07-01

    X-linked Charcot-Marie-Tooth disease (CMT1X) is the second most common inherited neuropathy, caused by mutations in gap junction beta-1 (GJB1). Males have a uniformly moderately severe phenotype while females have a variable phenotype, suggested to be due to X inactivation. We aimed to assess X inactivation pattern in females with CMT1X and correlate this with phenotype using the CMT examination score to determine whether the X inactivation pattern accounted for the variable phenotype in females with CMT1X. We determined X inactivation pattern in 67 females with CMT1X and 24 controls using the androgen receptor assay. We were able to determine which X chromosome carried the GJB1 mutation in 30 females. There was no difference in X inactivation pattern between patients and controls. In addition, there was no correlation between X inactivation pattern in blood and phenotype. A possible explanation for these findings is that the X inactivation pattern in Schwann cells rather than in blood may explain the variable phenotype in females with CMT1X.

  15. DNA Fragmentation Factor 45 (DFF45 Gene at 1p36.2 Is Homozygously Deleted and Encodes Variant Transcripts in Neuroblastoma Cell Line

    Directory of Open Access Journals (Sweden)

    Hong Wei Yang

    2001-01-01

    Full Text Available Recently, loss of heterozygosity (LOH studies suggest that more than two tumor suppressor genes lie on the short arm of chromosome 1 (1p in neuroblastoma (NB. To identify candidate tumor suppressor genes in NB, we searched for homozygous deletions in 20 NB cell lines using a high-density STS map spanning chromosome 1 p36, a common LOH region in NB. We found that the 45-kDa subunit of the DNA fragmentation factor (DFF45 gene was homozygously deleted in an NB cell line, NB-1. DFF45 is the chaperon of DFF40, and both molecules are necessary for caspase 3 to induce apoptosis. DFF35, a splicing variant of DFF45, is an inhibitor of DFF40. We examined 20 NB cell lines for expression and mutation of DFF45 gene by reverse transcription (RT-polymerase chain reaction (PCR and RT-PCR-single-strand conformation polymorphism. Some novel variant transcripts of the DFF45 gene were found in NB cell lines, but not in normal adrenal gland and peripheral blood. These variants may not serve as chaperons of DFF40, but as inhibitors like DFF35, thus disrupting the balance between DFF45 and DFF40. No mutations of the DFF45 gene were found in any NB cell line, suggesting that the DFF45 is not a tumor suppressor gene for NB. However, homozygous deletion of the DFF45 gene in the NB-1 cell line may imply the presence of unknown tumor suppressor genes in this region.

  16. Identification of a novel Gammaretrovirus in prostate tumors of patients homozygous for R462Q RNASEL variant.

    Directory of Open Access Journals (Sweden)

    Anatoly Urisman

    2006-03-01

    Full Text Available Ribonuclease L (RNase L is an important effector of the innate antiviral response. Mutations or variants that impair function of RNase L, particularly R462Q, have been proposed as susceptibility factors for prostate cancer. Given the role of this gene in viral defense, we sought to explore the possibility that a viral infection might contribute to prostate cancer in individuals harboring the R462Q variant. A viral detection DNA microarray composed of oligonucleotides corresponding to the most conserved sequences of all known viruses identified the presence of gammaretroviral sequences in cDNA samples from seven of 11 R462Q-homozygous (QQ cases, and in one of eight heterozygous (RQ and homozygous wild-type (RR cases. An expanded survey of 86 tumors by specific RT-PCR detected the virus in eight of 20 QQ cases (40%, compared with only one sample (1.5% among 66 RQ and RR cases. The full-length viral genome was cloned and sequenced independently from three positive QQ cases. The virus, named XMRV, is closely related to xenotropic murine leukemia viruses (MuLVs, but its sequence is clearly distinct from all known members of this group. Comparison of gag and pol sequences from different tumor isolates suggested infection with the same virus in all cases, yet sequence variation was consistent with the infections being independently acquired. Analysis of prostate tissues from XMRV-positive cases by in situ hybridization and immunohistochemistry showed that XMRV nucleic acid and protein can be detected in about 1% of stromal cells, predominantly fibroblasts and hematopoietic elements in regions adjacent to the carcinoma. These data provide to our knowledge the first demonstration that xenotropic MuLV-related viruses can produce an authentic human infection, and strongly implicate RNase L activity in the prevention or clearance of infection in vivo. These findings also raise questions about the possible relationship between exogenous infection and cancer

  17. Mutation Frequency and Spectrum of Mutations Vary at Different Chromosomal Positions of Pseudomonas putida

    Science.gov (United States)

    Juurik, Triinu; Ilves, Heili; Teras, Riho; Ilmjärv, Tanel; Tavita, Kairi; Ukkivi, Kärt; Teppo, Annika; Mikkel, Katren; Kivisaar, Maia

    2012-01-01

    It is still an open question whether mutation rate can vary across the bacterial chromosome. In this study, the occurrence of mutations within the same mutational target sequences at different chromosomal locations of Pseudomonas putida was monitored. For that purpose we constructed two mutation detection systems, one for monitoring the occurrence of a broad spectrum of mutations and transposition of IS element IS1411 inactivating LacI repressor, and another for detecting 1-bp deletions. Our results revealed that both the mutation frequency and the spectrum of mutations vary at different chromosomal positions. We observed higher mutation frequencies when the direction of transcription of the mutational target gene was opposite to the direction of replisome movement in the chromosome and vice versa, lower mutation frequency was accompanied with co-directional transcription and replication. Additionally, asymmetry of frameshift mutagenesis at homopolymeric and repetitive sequences during the leading and lagging-strand replication was found. The transposition frequency of IS1411 was also affected by the chromosomal location of the target site, which implies that regional differences in chromosomal topology may influence transposition of this mobile element. The occurrence of mutations in the P. putida chromosome was investigated both in growing and in stationary-phase bacteria. We found that the appearance of certain mutational hot spots is strongly affected by the chromosomal location of the mutational target sequence especially in growing bacteria. Also, artificial increasing transcription of the mutational target gene elevated the frequency of mutations in growing bacteria. PMID:23119042

  18. Drosophila CENP-A mutations cause a BubR1-dependent early mitotic delay without normal localization of kinetochore components.

    Directory of Open Access Journals (Sweden)

    Michael D Blower

    2006-07-01

    Full Text Available The centromere/kinetochore complex plays an essential role in cell and organismal viability by ensuring chromosome movements during mitosis and meiosis. The kinetochore also mediates the spindle attachment checkpoint (SAC, which delays anaphase initiation until all chromosomes have achieved bipolar attachment of kinetochores to the mitotic spindle. CENP-A proteins are centromere-specific chromatin components that provide both a structural and a functional foundation for kinetochore formation. Here we show that cells in Drosophila embryos homozygous for null mutations in CENP-A (CID display an early mitotic delay. This mitotic delay is not suppressed by inactivation of the DNA damage checkpoint and is unlikely to be the result of DNA damage. Surprisingly, mutation of the SAC component BUBR1 partially suppresses this mitotic delay. Furthermore, cid mutants retain an intact SAC response to spindle disruption despite the inability of many kinetochore proteins, including SAC components, to target to kinetochores. We propose that SAC components are able to monitor spindle assembly and inhibit cell cycle progression in the absence of sustained kinetochore localization.

  19. A Homozygous TPO Gene Duplication (c.1184_1187dup4) Causes Congenital Hypothyroidism in Three Siblings Born to a Consanguineous Family.

    Science.gov (United States)

    Cangul, Hakan; Aydin, Banu K; Bas, Firdevs

    2015-12-01

    Congenital hypothyroidism (CH) is the most common neonatal endocrine disease, and germ-line mutations in the TPO gene cause the inherited form of the disease. Our aim in this study was to determine the genetic basis of congenital hypothyroidism in three affected children coming from a consanguineous Turkish family. Because CH is usually inherited in autosomal recessive manner in consanguineous/multicase families, we adopted a two-stage strategy of genetic linkage studies and targeted sequencing of the candidate genes. First, we investigated the potential genetic linkage of the family to any known CH locus, using microsatellite markers, and then screened for mutations in linked-gene by conventional sequencing. The family showed potential linkage to the TPO gene and we detected a homozygous duplication (c.1184_1187dup4) in all cases. The mutation segregated with disease status in the family. This study confirms the pathogenicity of the c.1184_1187dup4 mutation in the TPO gene and helps establish a genotype/phenotype correlation associated with this mutation. It also highlights the importance of molecular genetic studies in the definitive diagnosis and accurate classification of CH.

  20. R1441C mutation in LRRK2 impairs dopaminergic neurotransmission in mice

    OpenAIRE

    Tong, Youren; Pisani, Antonio; Martella, Giuseppina; Karouani, Maha; Yamaguchi, Hiroo; Pothos, Emmanuel N.; Shen, Jie

    2009-01-01

    Dominantly inherited mutations in leucine-rich repeat kinase 2 (LRRK2) are a common genetic cause of Parkinson's disease (PD). The importance of the R1441 residue in the pathogenesis is highlighted by the identification of three distinct missense mutations. To investigate the pathogenic mechanism underlying LRRK2 dysfunction, we generated a knockin (KI) mouse in which the R1441C mutation is expressed under the control of the endogenous regulatory elements. Homozygous R1441C KI mice appear gro...

  1. Somatic mutations in aging, cancer and neurodegeneration.

    Science.gov (United States)

    Kennedy, Scott R; Loeb, Lawrence A; Herr, Alan J

    2012-04-01

    The somatic mutation theory of aging posits that the accumulation of mutations in the genetic material of somatic cells as a function of time results in a decrease in cellular function. In particular, the accumulation of random mutations may inactivate genes that are important for the functioning of the somatic cells of various organ systems of the adult, result in a decrease in organ function. When the organ function decreases below a critical level, death occurs. A significant amount of research has shown that somatic mutations play an important role in aging and a number of age related pathologies. In this review, we explore evidence for increases in somatic nuclear mutation burden with age and the consequences for aging, cancer, and neurodegeneration. We then review evidence for increases in mitochondrial mutation burden and the consequences for dysfunction in the disease processes. Copyright © 2011 Elsevier Ireland Ltd. All rights reserved.

  2. Prevalence of deafness in dogs heterozygous or homozygous for the merle allele.

    Science.gov (United States)

    Strain, G M; Clark, L A; Wahl, J M; Turner, A E; Murphy, K E

    2009-01-01

    Deafness in dogs is frequently associated with the pigment genes piebald and merle. Little is known about the prevalence of deafness in dogs carrying the merle allele. To determine the prevalence of deafness in dogs heterozygous and homozygous for the merle allele of the mouse Silver pigment locus homolog (SILV) gene. One hundred and fifty-three privately owned merle dogs of different breeds and both sexes. Hearing was tested by brainstem auditory-evoked response and classified as bilaterally hearing, unilaterally deaf, or bilaterally deaf. DNA from buccal cells was genotyped as either heterozygous or homozygous for the merle allele. Deafness association tests among merle genotype, eye color, and sex were performed by the chi(2) test. Deafness prevalence in merles overall was 4.6% unilaterally deaf and 4.6% bilaterally deaf. There was a significant association between hearing status and heterozygous versus homozygous merle genotype. For single merles (Mm), 2.7% were unilaterally deaf and 0.9% were bilaterally deaf. For double merles (MM), 10% were unilaterally deaf and 15% were bilaterally deaf. There was no significant association with eye color or sex. Deafness prevalence in merle dogs was greater than that in some dog breeds homozygous for the piebald gene, such as the English Cocker Spaniel, but comparable to, or lower than, that in the Dalmatian and white Bull Terrier. Dogs homozygous for the merle allele were significantly more likely to be deaf than heterozygotes.

  3. A molecular switch driving inactivation in the cardiac K+ channel HERG.

    Directory of Open Access Journals (Sweden)

    David A Köpfer

    Full Text Available K(+ channels control transmembrane action potentials by gating open or closed in response to external stimuli. Inactivation gating, involving a conformational change at the K(+ selectivity filter, has recently been recognized as a major K(+ channel regulatory mechanism. In the K(+ channel hERG, inactivation controls the length of the human cardiac action potential. Mutations impairing hERG inactivation cause life-threatening cardiac arrhythmia, which also occur as undesired side effects of drugs. In this paper, we report atomistic molecular dynamics simulations, complemented by mutational and electrophysiological studies, which suggest that the selectivity filter adopts a collapsed conformation in the inactivated state of hERG. The selectivity filter is gated by an intricate hydrogen bond network around residues S620 and N629. Mutations of this hydrogen bond network are shown to cause inactivation deficiency in electrophysiological measurements. In addition, drug-related conformational changes around the central cavity and pore helix provide a functional mechanism for newly discovered hERG activators.

  4. Phenylbutazone radicals inactivate creatine kinase.

    Science.gov (United States)

    Miura, T; Muraoka, S; Fujimoto, Y

    2001-02-01

    Creatine kinase (CK) was used as a marker molecule to examine the side effect of damage to tissues by phenylbutazone (PB), an effective drug to treat rheumatic and arthritic diseases, with horseradish peroxidase and hydrogen peroxide (HRP-H(2)O2). PB inactivated CK during its interaction with HRP-H(2) O(2), and inactivated CK in rat heart homogenate. PB carbon-centered radicals were formed during the interaction of PB with HRP-H(2)O2. The CK efficiently reduced electron spin resonance signals of the PB carbon-centered radicals. The spin trap agent 2-methyl-2-nitrosopropane strongly prevented CK inactivation. These results show that CK was inactivated through interaction with PB carbon-centered radicals. Sulfhydryl groups and tryptophan residues in CK were lost during the interaction of PB with HRP-H(2)O2, suggesting that cysteine and tryptophan residues are oxidized by PB carbon-centered radicals. Other enzymes, including alcohol dehydrogenase, glyceraldehyde-3-phosphate dehydrogenase, but not lactate dehydrogenase, were also inactivated. Sulfhydryl enzymes seem to be sensitive to attack by PB carbon-centered radicals. Inhibition of SH enzymes may explain some of the deleterious effects induced by PB.

  5. Pregnancy in a Woman with Homozygous Familial Hypercholesterolemia Not on Low-Density Lipoprotein Apheresis

    Directory of Open Access Journals (Sweden)

    Akl C. Fahed

    2012-11-01

    Full Text Available Pregnancy in women with homozygous familial hypercholesterolemia (FH has been rarely reported and might pose risks on the mother and her fetus. Although most reported cases remained on low-density lipoprotein (LDL apheresis, there are no clear guidelines regarding the management of this entity. We report the first case of an uncomplicated pregnancy in a 24-year-old homozygous FH woman who was not maintained on LDL apheresis. FH expresses a wide variability in the phenotype, and management of homozygous FH cases who desire to become pregnant should be individualized based on preconceptional assessment with frequent antenatal follow-up. Decisions on management should be made after weighing the risks versus benefits of LDL apheresis.

  6. Genetic screening for a single common LRRK2 mutation in familial Parkinson's disease.

    Science.gov (United States)

    Nichols, William C; Pankratz, Nathan; Hernandez, Dena; Paisán-Ruíz, Coro; Jain, Shushant; Halter, Cheryl A; Michaels, Veronika E; Reed, Terry; Rudolph, Alice; Shults, Clifford W; Singleton, Andrew; Foroud, Tatiana

    Mutations in the leucine-rich repeat kinase 2 (LRRK2) gene cause some forms of autosomal dominant Parkinson's disease. We measured the frequency of a novel mutation (Gly2019 ser) in familial Parkinson's disease by screening genomic DNA of patients and controls. Of 767 affected individuals from 358 multiplex families, 35 (5%) individuals were either heterozygous (34) or homozygous (one) for the mutation, and had typical clinical findings of idiopathic Parkinson's disease. Thus, our results suggest that a single LRRK2 mutation causes Parkinson's disease in 5% of individuals with familial disease. Screening for this mutation should be a component of genetic testing for Parkinson's disease.

  7. Inactivation of IL11 signaling causes craniosynostosis, delayed tooth eruption, and supernumerary teeth.

    Science.gov (United States)

    Nieminen, Pekka; Morgan, Neil V; Fenwick, Aimée L; Parmanen, Satu; Veistinen, Lotta; Mikkola, Marja L; van der Spek, Peter J; Giraud, Andrew; Judd, Louise; Arte, Sirpa; Brueton, Louise A; Wall, Steven A; Mathijssen, Irene M J; Maher, Eamonn R; Wilkie, Andrew O M; Kreiborg, Sven; Thesleff, Irma

    2011-07-15

    Craniosynostosis and supernumerary teeth most often occur as isolated developmental anomalies, but they are also separately manifested in several malformation syndromes. Here, we describe a human syndrome featuring craniosynostosis, maxillary hypoplasia, delayed tooth eruption, and supernumerary teeth. We performed homozygosity mapping in three unrelated consanguineous Pakistani families and localized the syndrome to a region in chromosome 9. Mutational analysis of candidate genes in the region revealed that all affected children harbored homozygous missense mutations (c.662C>G [p.Pro221Arg], c.734C>G [p.Ser245Cys], or c.886C>T [p.Arg296Trp]) in IL11RA (encoding interleukin 11 receptor, alpha) on chromosome 9p13.3. In addition, a homozygous nonsense mutation, c.475C>T (p.Gln159X), and a homozygous duplication, c.916_924dup (p.Thr306_Ser308dup), were observed in two north European families. In cell-transfection experiments, the p.Arg296Trp mutation rendered the receptor unable to mediate the IL11 signal, indicating that the mutation causes loss of IL11RA function. We also observed disturbed cranial growth and suture activity in the Il11ra null mutant mice, in which reduced size and remodeling of limb bones has been previously described. We conclude that IL11 signaling is essential for the normal development of craniofacial bones and teeth and that its function is to restrict suture fusion and tooth number. The results open up the possibility of modulation of IL11 signaling for the treatment of craniosynostosis. Copyright © 2011 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  8. Inactivation of IL11 Signaling Causes Craniosynostosis, Delayed Tooth Eruption, and Supernumerary Teeth

    Science.gov (United States)

    Nieminen, Pekka; Morgan, Neil V.; Fenwick, Aimée L.; Parmanen, Satu; Veistinen, Lotta; Mikkola, Marja L.; van der Spek, Peter J.; Giraud, Andrew; Judd, Louise; Arte, Sirpa; Brueton, Louise A.; Wall, Steven A.; Mathijssen, Irene M.J.; Maher, Eamonn R.; Wilkie, Andrew O.M.; Kreiborg, Sven; Thesleff, Irma

    2011-01-01

    Craniosynostosis and supernumerary teeth most often occur as isolated developmental anomalies, but they are also separately manifested in several malformation syndromes. Here, we describe a human syndrome featuring craniosynostosis, maxillary hypoplasia, delayed tooth eruption, and supernumerary teeth. We performed homozygosity mapping in three unrelated consanguineous Pakistani families and localized the syndrome to a region in chromosome 9. Mutational analysis of candidate genes in the region revealed that all affected children harbored homozygous missense mutations (c.662C>G [p.Pro221Arg], c.734C>G [p.Ser245Cys], or c.886C>T [p.Arg296Trp]) in IL11RA (encoding interleukin 11 receptor, alpha) on chromosome 9p13.3. In addition, a homozygous nonsense mutation, c.475C>T (p.Gln159X), and a homozygous duplication, c.916_924dup (p.Thr306_Ser308dup), were observed in two north European families. In cell-transfection experiments, the p.Arg296Trp mutation rendered the receptor unable to mediate the IL11 signal, indicating that the mutation causes loss of IL11RA function. We also observed disturbed cranial growth and suture activity in the Il11ra null mutant mice, in which reduced size and remodeling of limb bones has been previously described. We conclude that IL11 signaling is essential for the normal development of craniofacial bones and teeth and that its function is to restrict suture fusion and tooth number. The results open up the possibility of modulation of IL11 signaling for the treatment of craniosynostosis. PMID:21741611

  9. Frequent loss of chromosome 9, homozygous CDKN2A/p14(ARF)/CDKN2B deletion and low TSC1 mRNA expression in pleomorphic xanthoastrocytomas.

    Science.gov (United States)

    Weber, R G; Hoischen, A; Ehrler, M; Zipper, P; Kaulich, K; Blaschke, B; Becker, A J; Weber-Mangal, S; Jauch, A; Radlwimmer, B; Schramm, J; Wiestler, O D; Lichter, P; Reifenberger, G

    2007-02-15

    The molecular pathogenesis of pleomorphic xanthoastrocytoma (PXA), a rare astrocytic brain tumor with a relatively favorable prognosis, is still poorly understood. We characterized 50 PXAs by comparative genomic hybridization (CGH) and found the most common imbalance to be loss on chromosome 9 in 50% of tumors. Other recurrent losses affected chromosomes 17 (10%), 8, 18, 22 (4% each). Recurrent gains were identified on chromosomes X (16%), 7, 9q, 20 (8% each), 4, 5, 19 (4% each). Two tumors demonstrated amplifications mapping to 2p23-p25, 4p15, 12q13, 12q21, 21q21 and 21q22. Analysis of 10 PXAs with available high molecular weight DNA by high-resolution array-based CGH indicated homozygous 9p21.3 deletions involving the CDKN2A/p14(ARF)/CDKN2B loci in six tumors (60%). Interphase fluorescence in situ hybridization to tissue sections confirmed the presence of tumor cells with homozygous 9p21.3 deletions. Mutational analysis of candidate genes on 9q, PTCH and TSC1, revealed no mutations in PXAs with 9q loss and no evidence of TSC1 promoter methylation. However, PXAs consistently showed low TSC1 transcript levels. Taken together, our study identifies loss of chromosome 9 as the most common chromosomal imbalance in PXAs and suggests important roles for homozygous CDKN2A/p14(ARF)/CDKN2B deletion as well as low TSC1 mRNA expression in these tumors.

  10. Missense and nonsense mutations in melanocortin 1 receptor (MC1R gene of different goat breeds: association with red and black coat colour phenotypes but with unexpected evidences

    Directory of Open Access Journals (Sweden)

    Davoli Roberta

    2009-08-01

    Full Text Available Abstract Background Agouti and Extension loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The Extension locus encodes the melanocortin 1 receptor (MC1R whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals. Results The whole coding region of the MC1R gene was sequenced in goats of six different breeds showing different coat colours (Girgentana, white cream with usually small red spots in the face; Maltese, white with black cheeks and ears; Derivata di Siria, solid red; Murciano-Granadina, solid black or solid brown; Camosciata delle Alpi, brown with black stripes; Saanen, white; F1 goats and the parental animals. Five single nucleotide polymorphisms (SNPs were identified: one nonsense mutation (p.Q225X, three missense mutations (p.A81V, p.F250V, and p.C267W, and one silent mutation. The stop codon at position 225 should cause the production of a shorter MC1R protein whose functionality may be altered. These SNPs were investigated in a larger sample of animals belonging to the six breeds. The Girgentana breed was almost fixed for the p.225X allele. However, there was not complete association between the presence of red spots in the face and the presence of this allele in homozygous condition. The same allele was identified in the Derivata di Siria breed. However, its frequency was only 33%, despite the fact that these animals are completely red. The p.267W allele was present in all Murciano-Granadina black goats, whereas it was never identified in the brown ones. Moreover, the same substitution was present in almost all Maltese goats providing evidence of association between this mutation and black coat colour. Conclusion According to the results obtained in the investigated goat breeds, MC1R mutations may determine eumelanic and pheomelanic

  11. Missense and nonsense mutations in melanocortin 1 receptor (MC1R) gene of different goat breeds: association with red and black coat colour phenotypes but with unexpected evidences.

    Science.gov (United States)

    Fontanesi, Luca; Beretti, Francesca; Riggio, Valentina; Dall'Olio, Stefania; González, Elena Gómez; Finocchiaro, Raffaella; Davoli, Roberta; Russo, Vincenzo; Portolano, Baldassare

    2009-08-25

    Agouti and Extension loci control the relative amount of eumelanin and pheomelanin production in melanocytes that, in turn, affects pigmentation of skin and hair. The Extension locus encodes the melanocortin 1 receptor (MC1R) whose permanent activation, caused by functional mutations, results in black coat colour, whereas other inactivating mutations cause red coat colour in different mammals. The whole coding region of the MC1R gene was sequenced in goats of six different breeds showing different coat colours (Girgentana, white cream with usually small red spots in the face; Maltese, white with black cheeks and ears; Derivata di Siria, solid red; Murciano-Granadina, solid black or solid brown; Camosciata delle Alpi, brown with black stripes; Saanen, white; F1 goats and the parental animals). Five single nucleotide polymorphisms (SNPs) were identified: one nonsense mutation (p.Q225X), three missense mutations (p.A81V, p.F250V, and p.C267W), and one silent mutation. The stop codon at position 225 should cause the production of a shorter MC1R protein whose functionality may be altered. These SNPs were investigated in a larger sample of animals belonging to the six breeds. The Girgentana breed was almost fixed for the p.225X allele. However, there was not complete association between the presence of red spots in the face and the presence of this allele in homozygous condition. The same allele was identified in the Derivata di Siria breed. However, its frequency was only 33%, despite the fact that these animals are completely red. The p.267W allele was present in all Murciano-Granadina black goats, whereas it was never identified in the brown ones. Moreover, the same substitution was present in almost all Maltese goats providing evidence of association between this mutation and black coat colour. According to the results obtained in the investigated goat breeds, MC1R mutations may determine eumelanic and pheomelanic phenotypes. However, they are probably not the only

  12. Induction of ovarian leiomyosarcomas in mice by conditional inactivation of Brca1 and p53.

    Directory of Open Access Journals (Sweden)

    Bridget A Quinn

    2009-12-01

    Full Text Available Approximately one out of every ten cases of epithelial ovarian cancer (EOC is inherited. The majority of inherited cases of EOC result from mutations in the breast cancer associated gene 1 (BRCA1. In addition to mutation of BRCA1, mutation of the p53 gene is often found in patients with inherited breast and ovarian cancer syndrome.We investigated the role of loss of function of BRCA1 and p53 in ovarian cancer development using mouse models with conditionally expressed alleles of Brca1 and/or p53. Our results show that ovary-specific Cre-recombinase-mediated conditional inactivation of both Brca1(LoxP/LoxP and p53(LoxP/LoxP resulted in ovarian or reproductive tract tumor formation in 54% of mice, whereas conditional inactivation of either allele alone infrequently resulted in tumors (< or =5% of mice. In mice with conditionally inactivated Brca1(LoxP/LoxP and p53(LoxP/LoxP, ovarian tumors arose after long latency with the majority exhibiting histological features consistent with high grade leiomyosarcomas lacking expression of epithelial, follicular or lymphocyte markers. In addition, tumors with conditional inactivation of both Brca1(LoxP/LoxP and p53(LoxP/LoxP exhibited greater genomic instability compared to an ovarian tumor with inactivation of only p53(LoxP/LoxP.Although conditional inactivation of both Brca1 and p53 results in ovarian tumorigenesis, our results suggest that additional genetic alterations or alternative methods for targeting epithelial cells of the ovary or fallopian tube for conditional inactivation of Brca1 and p53 are required for the development of a mouse model of Brca1-associated inherited EOC.

  13. A family with hereditary hemochromatosis carrying HFE gene splice site mutation: a case report

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    NING Huibin

    2017-01-01

    Full Text Available ObjectiveTo investigate a new type of HFE gene mutation in a family with hereditary hemochromatosis (HH. MethodsThe analysis of HFE gene was performed for one patient with a confirmed diagnosis of HH and five relatives. Blood genomic DNA was extracted and PCR multiplication was performed for the exon and intron splice sequences of related HFE, HJV, HAMP, transferrin receptor 2 (TfR2, and SLC40A1 genes. After agarose gel electrophoresis and purification, bi-directional direct sequencing was performed to detect mutation sites. ResultsThe proband had abnormal liver function and increases in serum iron, total iron binding capacity, serum ferritin, and transferrin saturation, as well as T→C homozygous mutation in the fourth base of intron 2 in the intervening sequence of the exon EXON2 of HFE gene (IVs 2+4T→C, C/C homozygous, splicing, abnormal. There were no abnormalities in HJV, HAMP, TfR2, and SLC40A1 genes. The proband′s son had the same homozygous mutation, three relatives had heterozygous mutations, and one relative had no abnormal mutations. ConclusionGene detection plays an important role in the diagnosis of hemochromatosis, and IVs 2+4T→C mutation may be a new pathogenic mutation for HH in China.

  14. Role of Merlin/NF2 inactivation in tumor biology.

    Science.gov (United States)

    Petrilli, A M; Fernández-Valle, C

    2016-02-04

    Merlin (Moesin-ezrin-radixin-like protein, also known as schwannomin) is a tumor suppressor protein encoded by the neurofibromatosis type 2 gene NF2. Loss of function mutations or deletions in NF2 cause neurofibromatosis type 2 (NF2), a multiple tumor forming disease of the nervous system. NF2 is characterized by the development of bilateral vestibular schwannomas. Patients with NF2 can also develop schwannomas on other cranial and peripheral nerves, as well as meningiomas and ependymomas. The only potential treatment is surgery/radiosurgery, which often results in loss of function of the involved nerve. There is an urgent need for chemotherapies that slow or eliminate tumors and prevent their formation in NF2 patients. Interestingly NF2 mutations and merlin inactivation also occur in spontaneous schwannomas and meningiomas, as well as other types of cancer including mesothelioma, glioma multiforme, breast, colorectal, skin, clear cell renal cell carcinoma, hepatic and prostate cancer. Except for malignant mesotheliomas, the role of NF2 mutation or inactivation has not received much attention in cancer, and NF2 might be relevant for prognosis and future chemotherapeutic approaches. This review discusses the influence of merlin loss of function in NF2-related tumors and common human cancers. We also discuss the NF2 gene status and merlin signaling pathways affected in the different tumor types and the molecular mechanisms that lead to tumorigenesis, progression and pharmacological resistance.

  15. Characterization of Alu and recombination-associated motifs mediating a large homozygous SPG7 gene rearrangement causing hereditary spastic paraplegia.

    Science.gov (United States)

    López, Eva; Casasnovas, Carlos; Giménez, Javier; Matilla-Dueñas, Antoni; Sánchez, Ivelisse; Volpini, Víctor

    2015-04-01

    Spastic paraplegia type 7 (SPG7) is one of the most common forms of autosomal recessive hereditary spastic paraplegia (AR-HSP). Although over 77 different mutations have been identified in SPG7 patients, only 9 gross deletions have been reported with only a few of them being fully characterized. Here, we present a detailed description of a large homozygous intragenic SPG7 gene rearrangement involving a 5144-base pair (bp) genomic loss (c. 1450-446_1779 + 746 delinsAAAGTGCT) encompassing exons 11 to 13, identified in a Spanish AR-HSP family. Analysis of the deletion junction sequences revealed that the 5' breakpoint of this SPG7 gene deletion was located within highly homologous Alu sequences where the 3' breakpoint appears to be flanked by the core crossover hotspot instigator (chi)-like sequence (GCTGG). Furthermore, an 8-bp (AAAGTTGCT) conserved sequence at the breakpoint junction was identified, suggesting that the most likely mechanism for the occurrence of this rearrangement is by Alu microhomology and chi-like recombination-associated motif-mediated multiple exon deletion. Our results are consistent with non-allelic homologous recombination and non-homologous end joining in deletion mutagenesis for the generation of rearrangements. This study provides more evidence associating repeated elements as a genetic mechanism underlying neurodegenerative disorders, highlighting their importance in human diseases.

  16. Influenza Vaccine, Inactivated or Recombinant

    Science.gov (United States)

    ... die from flu, and many more are hospitalized.Flu vaccine can:keep you from getting flu, make flu ... What is inactivated or recombinant influenza vaccine?A dose of flu vaccine is recommended every flu season. Children 6 months through 8 years of age may need two ...

  17. The hippocampal corticosterone receptor system of the homozygous diabetes insipidus (Brattleboro) rat

    NARCIS (Netherlands)

    de Kloet, E R; Veldhuis, H D

    The binding of [3H] corticosterone to hippocampal cytosol receptors of Brattleboro rats homozygous for diabetes insipidus (Ho-Di) and of normal Brattleboro rats (Ho-No) was investigated at 24 h after removal of the adrenals. The apparent maximal binding capacity of the Ho-Di hippocampal

  18. Generation of a homozygous GBA deletion human embryonic stem cell line

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    Anna Lisa Gündner

    2017-08-01

    Full Text Available We describe the generation of a biallelic GBA deletion human embryonic stem cell line using zinc finger nuclease-mediated gene targeting. The homozygous targeting of exon 4 of the GBA locus leads to a complete loss of glucocerebrosidase (GCase protein expression.

  19. Identification of a c.544C>T mutation in WDR34 as a deleterious recessive allele of short rib-polydactyly syndrome

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    Shu-Han You

    2017-12-01

    Conclusion: This study was the first to identify c.544C > T [p.Arg182Trp] mutation in WDR34 in a patient with SRPS. According to the database, the homozygous mutation of c.544C > T in WDR34 was deleterious and the prevalence of heterozygous mutation was relatively higher in Asian population. More studies of this mutation in patients with SRPS are required.

  20. Disruption of NBS1 gene leads to early embryonic lethality in homozygous null mice and induces specific cancer in heterozygous mice

    Energy Technology Data Exchange (ETDEWEB)

    Kurimasa, Akihiro; Burma, Sandeep; Henrie, Melinda; Ouyang, Honghai; Osaki, Mitsuhiko; Ito, Hisao; Nagasawa, Hatsumi; Little, John B.; Oshimura, Mitsuo; Li, Gloria C.; Chen, David J.

    2002-04-15

    Nijmegen breakage syndrome (NBS) is a rare autosomal recessive chromosome instability syndrome characterized by microcephaly, growth retardation, immunodeficiency, and cancer predisposition, with cellular features similar to that of ataxia telangiectasia (AT). NBS results from mutations in the mammalian gene Nbs1 that codes for a 95-kDa protein called nibrin, NBS1, or p95. To establish an animal model for NBS, we attempted to generate NBS1 knockout mice. However, NBS1 gene knockouts were lethal at an early embryonic stage. NBS1 homozygous(-/-) blastocyst cells cultured in vitro showed retarded growth and subsequently underwent growth arrest within 5 days of culture. Apoptosis, assayed by TUNEL staining, was observed in NBSI homozygous(-/-) blastocyst cells cultured for four days. NBSI heterozygous(+/-) mice were normal, and exhibited no specific phenotype for at least one year. However, fibroblast cells from NBSI heterozygous(+/-) mice displayed an enhanced frequency of spontaneous transformation to anchorage-independent growth as compared to NBS1 wild-type(+/+) cells. Furthermore, heterozygous(+/-) mice exhibited a high incidence of hepatocellular carcinoma after one year compared to wild-type mice, even though no significant differences in the incidence of other tumors such as lung adenocarcinoma and lymphoma were observed. Taken together, these results strongly suggest that NBS1 heterozygosity and reduced NBSI expression induces formation of specific tumors in mice.

  1. Increased microerythrocyte count in homozygous alpha(+-thalassaemia contributes to protection against severe malarial anaemia.

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    Freya J I Fowkes

    2008-03-01

    Full Text Available The heritable haemoglobinopathy alpha(+-thalassaemia is caused by the reduced synthesis of alpha-globin chains that form part of normal adult haemoglobin (Hb. Individuals homozygous for alpha(+-thalassaemia have microcytosis and an increased erythrocyte count. Alpha(+-thalassaemia homozygosity confers considerable protection against severe malaria, including severe malarial anaemia (SMA (Hb concentration 1.1 x 10(12/l as a result of the reduced mean cell Hb in homozygous alpha(+-thalassaemia. In addition, children homozygous for alpha(+-thalassaemia require a 10% greater reduction in erythrocyte count than children of normal genotype (p = 0.02 for Hb concentration to fall to 50 g/l, the cutoff for SMA. We estimated that the haematological profile in children homozygous for alpha(+-thalassaemia reduces the risk of SMA during acute malaria compared to children of normal genotype (relative risk 0.52; 95% confidence interval [CI] 0.24-1.12, p = 0.09.The increased erythrocyte count and microcytosis in children homozygous for alpha(+-thalassaemia may contribute substantially to their protection against SMA. A lower concentration of Hb per erythrocyte and a larger population of erythrocytes may be a biologically advantageous strategy against the significant reduction in erythrocyte count that occurs during acute infection with the malaria parasite Plasmodium falciparum. This haematological profile may reduce the risk of anaemia by other Plasmodium species, as well as other causes of anaemia. Other host polymorphisms that induce an increased erythrocyte count and microcytosis may confer a similar advantage.

  2. Role of p53 and CDKN2A Inactivation in Human Squamous Cell Carcinomas

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    Alessia Pacifico

    2007-01-01

    Several studies have shown that human SCCs harbour unique mutations in the p53 gene as well as inactivation of the CDKN2A gene. While mutations in the p53 gene are induced by UV radiation and represent tumor initiating events, the majority of alterations detected in the CDKN2A gene do not appear to be UV-dependent. In conclusion, in addition to p53 mutations, silencing of the CDKN2A gene might play a significant role in SCC development.

  3. Somatic mutations of the histone H3K27 demethylase, UTX, in human cancer

    OpenAIRE

    van Haaften, Gijs; Dalgliesh, Gillian L; Davies, Helen; Chen, Lina; Bignell, Graham; Greenman, Chris; Edkins, Sarah; Hardy, Claire; O?Meara, Sarah; Teague, Jon; Butler, Adam; Hinton, Jonathan; Latimer, Calli; Andrews, Jenny; Barthorpe, Syd

    2009-01-01

    Somatically acquired epigenetic changes are present in many cancers. Epigenetic regulation is maintained via post-translational modifications of core histones. Here, we describe inactivating somatic mutations in the histone lysine demethylase, UTX, pointing to histone H3 lysine methylation deregulation in multiple tumour types. UTX reintroduction into cancer cells with inactivating UTX mutations resulted in slowing of proliferation and marked transcriptional changes. These data identify UTX a...

  4. Co-inheritance of α0 -thalassemia elevates Hb A2 level in homozygous Hb E: Diagnostic implications.

    Science.gov (United States)

    Singha, K; Srivorakun, H; Fucharoen, G; Fucharoen, S

    2017-10-01

    Differentiation of homozygous hemoglobin (Hb) E with and without α0 -thalassemia is subtle on routine hematological ground. We examined in a large cohort of homozygous Hb E if the level of Hb A2 is helpful. A total of 592 subjects with homozygous Hb E were recruited from ongoing thalassemia screening program. Additionally, five couples at risk of having fetuses with Hb Bart's hydrops fetalis who were homozygous Hb E were also investigated. Hb analysis was performed using capillary electrophoresis system. Globin genotypes were defined by DNA analysis. Subjects were classified into four groups including pure homozygous Hb E (n=532), homozygous Hb E/α0 -thalassemia (n=48), Hb Constant Spring EE Bart's disease (n=8), and Hb EE Bart's disease (n=4). The levels of Hb A2 were found, respectively, to be 4.97±0.69, 6.64±1.02, 4.86±0.87, and 7.60±1.04%. Among five couples at risk, α0 -thalassemia was identified in three subjects with Hb A2 >6.0%. Increased Hb A2 level is a useful marker for differentiation of homozygous Hb E with and without α0 -thalassemia. This should lead to a significant reduction in number of referral cases of homozygous Hb E for molecular testing of α0 -thalassemia in routine practice. © 2017 John Wiley & Sons Ltd.

  5. Hereditary spastic paraplegia with recessive trait caused by mutation in KLC4 gene.

    Science.gov (United States)

    Bayrakli, Fatih; Poyrazoglu, Hatice Gamze; Yuksel, Sirin; Yakicier, Cengiz; Erguner, Bekir; Sagiroglu, Mahmut Samil; Yuceturk, Betul; Ozer, Bugra; Doganay, Selim; Tanrikulu, Bahattin; Seker, Askin; Akbulut, Fatih; Ozen, Ali; Per, Huseyin; Kumandas, Sefer; Altuner Torun, Yasemin; Bayri, Yasar; Sakar, Mustafa; Dagcinar, Adnan; Ziyal, Ibrahim

    2015-12-01

    We report an association between a new causative gene and spastic paraplegia, which is a genetically heterogeneous disorder. Clinical phenotyping of one consanguineous family followed by combined homozygosity mapping and whole-exome sequencing analysis. Three patients from the same family shared common features of progressive complicated spastic paraplegia. They shared a single homozygous stretch area on chromosome 6. Whole-exome sequencing revealed a homozygous mutation (c.853_871del19) in the gene coding the kinesin light chain 4 protein (KLC4). Meanwhile, the unaffected parents and two siblings were heterozygous and one sibling was homozygous wild type. The 19 bp deletion in exon 6 generates a stop codon and thus a truncated messenger RNA and protein. The association of a KLC4 mutation with spastic paraplegia identifies a new locus for the disease.

  6. [Analysis common gene mutation spots of 127 non-syndromic deafness natients in Guangxi Drovince].

    Science.gov (United States)

    Liu, Shuixia; Xu, Liang; Chen, Bowen; Liu, Min; Qu, Shenghong; Liang, Jianping; Tang, Fengzhu; Shi, Min; Peng, Lu; Jing, Yan; Li, Fengti; Liang, Youqiong

    2015-11-01

    To investigate the mutation characteristics of common deafness gene from 127 non-syndromic hearing loss patients in Guangxi province. Deafness-related gene mutations detection kit was used to detect 15 mutation sites in four deafness-associated genes, and a total of 127 hearing impaired patients were tested. The samples that could not be diagnosed with DNA microarray were subjected to PCR and sequenced to detect other mutations. Among the 127 patients with non-syndromic deafness, the total mutation rate is 8.66% (11/127), including GJB2 235delC homozygous in 3 cases (2.36%), 235delC single heterozygous mutation in 2 cases (1.57%), GJB2 235delC and 109 A > G mutations in 2 cases (1.57%); SLC26A4 1229C > T homozygous in 1 case (0.79%), IVS7-2A > G, IVS11 + 47T > C and 15448insC mutaion in 2 cases (1.57%); mitochondrial 12S rRNA gene mutations were not detected. The result indicates that GJB2 and SLC26A4 were the main genes in this study, and the mutation rate is significantly lower than the national average level. Three new mutations (SLC26A4 IVS11 + 47T > C,1548insC and GJB2 109A > G) were found. There may be rare mutations among sites or genes associated with deafness in Guangxi.

  7. Expanding the clinical and mutational spectrum of Kaufman oculocerebrofacial syndrome with biallelic UBE3B mutations.

    Science.gov (United States)

    Basel-Vanagaite, Lina; Yilmaz, Rüstem; Tang, Sha; Reuter, Miriam S; Rahner, Nils; Grange, Dorothy K; Mortenson, Megan; Koty, Patrick; Feenstra, Heather; Farwell Gonzalez, Kelly D; Sticht, Heinrich; Boddaert, Nathalie; Désir, Julie; Anyane-Yeboa, Kwame; Zweier, Christiane; Reis, André; Kubisch, Christian; Jewett, Tamison; Zeng, Wenqi; Borck, Guntram

    2014-07-01

    Biallelic mutations of UBE3B have recently been shown to cause Kaufman oculocerebrofacial syndrome (also reported as blepharophimosis-ptosis-intellectual disability syndrome), an autosomal recessive condition characterized by hypotonia, developmental delay, intellectual disability, congenital anomalies, characteristic facial dysmorphic features, and low cholesterol levels. To date, six patients with either missense mutations affecting the UBE3B HECT domain or truncating mutations have been described. Here, we report on the identification of homozygous or compound heterozygous UBE3B mutations in six additional patients from five unrelated families using either targeted UBE3B sequencing in individuals with suggestive facial dysmorphic features, or exome sequencing. Our results expand the clinical and mutational spectrum of the UBE3B-related disorder in several ways. First, we have identified UBE3B mutations in individuals who previously received distinct clinical diagnoses: two sibs with Toriello-Carey syndrome as well as the patient reported to have a "new" syndrome by Buntinx and Majewski in 1990. Second, we describe the adult phenotype and clinical variability of the syndrome. Third, we report on the first instance of homozygous missense alterations outside the HECT domain of UBE3B, observed in a patient with mildly dysmorphic facial features. We conclude that UBE3B mutations cause a clinically recognizable and possibly underdiagnosed syndrome characterized by distinct craniofacial features, hypotonia, failure to thrive, eye abnormalities, other congenital malformations, low cholesterol levels, and severe intellectual disability. We review the UBE3B-associated phenotypes, including forms that can mimick Toriello-Carey syndrome, and suggest the single designation "Kaufman oculocerebrofacial syndrome".

  8. Hyperactivated Wnt signaling induces synthetic lethal interaction with Rb inactivation by elevating TORC1 activities.

    Directory of Open Access Journals (Sweden)

    Tianyi Zhang

    2014-05-01

    Full Text Available Inactivation of the Rb tumor suppressor can lead to increased cell proliferation or cell death depending on specific cellular context. Therefore, identification of the interacting pathways that modulate the effect of Rb loss will provide novel insights into the roles of Rb in cancer development and promote new therapeutic strategies. Here, we identify a novel synthetic lethal interaction between Rb inactivation and deregulated Wg/Wnt signaling through unbiased genetic screens. We show that a weak allele of axin, which deregulates Wg signaling and increases cell proliferation without obvious effects on cell fate specification, significantly alters metabolic gene expression, causes hypersensitivity to metabolic stress induced by fasting, and induces synergistic apoptosis with mutation of fly Rb ortholog, rbf. Furthermore, hyperactivation of Wg signaling by other components of the Wg pathway also induces synergistic apoptosis with rbf. We show that hyperactivated Wg signaling significantly increases TORC1 activity and induces excessive energy stress with rbf mutation. Inhibition of TORC1 activity significantly suppressed synergistic cell death induced by hyperactivated Wg signaling and rbf inactivation, which is correlated with decreased energy stress and decreased induction of apoptotic regulator expression. Finally the synthetic lethality between Rb and deregulated Wnt signaling is conserved in mammalian cells and that inactivation of Rb and APC induces synergistic cell death through a similar mechanism. These results suggest that elevated TORC1 activity and metabolic stress underpin the evolutionarily conserved synthetic lethal interaction between hyperactivated Wnt signaling and inactivated Rb tumor suppressor.

  9. Inactivation of rabies virus by hydrogen peroxide.

    Science.gov (United States)

    Abd-Elghaffar, Asmaa A; Ali, Amal E; Boseila, Abeer A; Amin, Magdy A

    2016-02-03

    Development of safe and protective vaccines against infectious pathogens remains a challenge. Inactivation of rabies virus is a critical step in the production of vaccines and other research reagents. Beta-propiolactone (βPL); the currently used inactivating agent for rabies virus is expensive and proved to be carcinogenic in animals. This study aimed to investigate the ability of hydrogen peroxide (H2O2) to irreversibly inactivate rabies virus without affecting its antigenicity and immunogenicity in pursuit of finding safe, effective and inexpensive alternative inactivating agents. H2O2 3% rapidly inactivated a Vero cell adapted fixed rabies virus strain designated as FRV/K within 2h of exposure without affecting its antigenicity or immunogenicity. No residual infectious virus was detected and the H2O2-inactivated vaccine proved to be safe and effective when compared with the same virus harvest inactivated with the classical inactivating agent βPL. Mice immunized with H2O2-inactivated rabies virus produced sufficient level of antibodies and were protected when challenged with lethal CVS virus. These findings reinforce the idea that H2O2 can replace βPL as inactivating agent for rabies virus to reduce time and cost of inactivation process. Copyright © 2015 Elsevier Ltd. All rights reserved.

  10. Cloning of the laminin {alpha}3 chain gene (LAMA3) and identification of a homozygous deletion in a patient with Herlitz junctional epidermolysis bullosa

    Energy Technology Data Exchange (ETDEWEB)

    Vidal, F.; Ortonne, J.P. [INSERM, Nice (France)]|[Hospital Pasteur, Nice (France); Galliano, M.F. [INSERM, Nice (France)] [and others

    1995-11-20

    Laminin 5 and laminin 6 are basement membrane proteins synthesized by the basal cells of stratifying squamous epithelia. Altered expression of laminin 5 has been associated with Herlitz junctional epidermolysis bullosa (H-JEB), a severe epidermal blistering disorder inherited as an autosomal recessive disease. We have isolated cDNA clones encoding the {alpha}3 chain of laminin 5 and searched for mutations in the LAMA3 gene in H-JEB patients. In one H-JEB family, an affected individual exhibited drastically reduced immunoreactivity to antibodies directed against the {alpha}3 chain of laminin 5 and an impaired expression of the corresponding mRNA transcripts. RT-PCR analysis of mRNA extracted from the proband`s keratinocytes identified a homozygous single basepair deletion in the transcripts encoding the laminin {alpha}3A and {alpha}3B isoforms. The mutation causes a frameshift and premature termination codon in both alleles of the LAMA3 gene. Inheritance of the clinical H-JEB phenotype was consistent with the segregation of the mutated allele in the family. We also report the identity of the {alpha} chains of laminin 5 and epiligrin and provide evidence that LAMA3 transcripts are distinct from the laminin 6 {alpha} chain mRNA. 35 refs., 5 figs., 1 tab.

  11. GJA12 mutations in children with recessive hypomyelinating leukoencephalopathy.

    Science.gov (United States)

    Bugiani, M; Al Shahwan, S; Lamantea, E; Bizzi, A; Bakhsh, E; Moroni, I; Balestrini, M R; Uziel, G; Zeviani, M

    2006-07-25

    Pelizaeus-Merzbacher-like disease (PMLD) is an inherited hypomyelinating leukoencephalopathy with onset in early infancy. Like Pelizaeus-Merzbacher disease (PMD), PMLD is characterized clinically by nystagmus, cerebellar ataxia, and spasticity, due to a permanent lack of myelin deposition in the brain. Mutations in the GJA12 gene, encoding connexin 47 (Cx47), were recently reported in five children with autosomal recessive PMLD. To evaluate the impact of mutations in the GJA12 gene in, and define the clinical and neuroimaging features of, autosomal recessive PMLD. The authors screened for GJA12 mutations in 10 additional PMLD families originating from Italy, Pakistan, and Saudi Arabia. Three novel homozygous GJA12 mutations were identified in 12 mutant cases distributed in 3 of 10 families. The mutations segregated with the disease according to an autosomal recessive trait and included one missense (G236S) and two nonsense (L281fs285X and P131fs144X) changes. The identification of homozygous mutations predicting the synthesis of aberrant and truncated polypeptides, and their tight segregation with the disease in very large families, clearly demonstrate that the loss of Cx47 function is the cause of the disease. The phenotype of GJA12-related Pelizaeus-Merzbacher-like disease is fairly homogeneous and similar to that of Pelizaeus-Merzbacher disease. However, slower progression of symptoms, greater preservation of cognitive functions, and partial myelination of corticospinal tracts at MRI were distinctive features, which could help in the differential diagnosis.

  12. Kinetics and thermodynamics of the native and mutated extracellular endo-glucanases from Cellulomonas biazotea.

    Science.gov (United States)

    Rajoka, M I; Ashraf, Yasmin; Rashid, Hamid; Khalid, A M

    2003-12-01

    The mutation had dramatic effect on the kinetic and thermodynamic parameters inferring thermostability of endo-glucanase from Cellulomonas biazotea mutant 51 SM(r). The denaturation activation energies of native and mutated enzymes were 73.3 and 68.8 kJ/mol respectively. They showed compensation effect at 55 degrees C. Both enthalpy and entropy values of irreversible thermal inactivation for mutated enzyme were decreased suggesting that the mutation partly stabilized the enzyme.

  13. Cell autonomy of the mouse claw paw mutation

    OpenAIRE

    Darbas, Aysel; Jaegle, Martine; Walbeehm, Erik; van den Burg, Hans; Driegen, Siska; Broos, Ludo; Uyl, Matthijs; Visser, Pim; Grosveld, Frank; Meijer, Dies

    2004-01-01

    textabstractMice homozygous for the autosomal recessive mutation claw paw (clp) are characterized by limb posture abnormalities and congenital hypomyelination, with delayed onset of myelination of the peripheral nervous system but not the central nervous system. Although this combination of limb and peripheral nerve abnormalities in clp/clp mice might suggest a common neurogenic origin of the syndrome, it is not clear whether the clp gene acts primarily in the neurone, the Schwann cell or bot...

  14. Molecular analysis of the fibrinogen gene cluster in 16 patients with congenital afibrinogenemia: novel truncating mutations in the FGA and FGG genes.

    Science.gov (United States)

    Neerman-Arbez, M; de Moerloose, P; Honsberger, A; Parlier, G; Arnuti, B; Biron, C; Borg, J Y; Eber, S; Meili, E; Peter-Salonen, K; Ripoll, L; Vervel, C; d'Oiron, R; Staeger, P; Antonarakis, S E; Morris, M A

    2001-03-01

    Congenital afibrinogenemia is an autosomal recessive disorder characterized by the complete absence of detectable fibrinogen. We previously identified the first causative mutations for this disease in a non-consanguineous Swiss family. These were homozygous deletions of approximately 11 kb of the fibrinogen alpha chain gene (FGA). Our subsequent study revealed that the majority of cases were attributable to truncating mutations in FGA, with the most common mutation affecting the donor splice site in FGA intron 4 (IVS4+1 G-->T). Here, we report 13 further unrelated patients with mutations in FGA, confirming the relative importance of this gene compared with FGG and FGB in the molecular aetiology of afibrinogenemia. Three other patients were homozygous for mutations in FGG. Eight novel mutations were identified: five in FGA and three in FGG. Sufficient mutation data is now available to permit an effective strategy for the genetic diagnosis of congenital afibrinogenemia.

  15. Evaluation of Lama5 as a candidate for the mouse ragged (Ra) mutation

    DEFF Research Database (Denmark)

    Durkin, M E; Albrechtsen, R; Chambers, D M

    1998-01-01

    The laminin alpha5 chain is a component of the basement membranes of many developing and adult tissues. The mouse laminin alpha5 chain gene (Lama5) has been mapped close to the locus of the semidominant ragged (Ra) mutation on distal chromosome 2. The cause of the Ra mutation, which is usually...... lethal in the homozygous state, has not been determined. We have investigated whether a defect in Lama5 is responsible for the ragged mutation, using the RaJ strain. No differences in the level of the laminin alpha5 chain transcript were found in placental RNA from homozygous RaJ mutant embryos compared....... These results exclude Lama5 as a candidate gene for the Ra mutation....

  16. CFTR H609R mutation in Ecuadorian patients with cystic fibrosis.

    Science.gov (United States)

    Moya-Quiles, María Rosa; Glover, Guillermo; Mondéjar-López, Pedro; Pastor-Vivero, María Dolores; Fernández-Sánchez, Asunción; Sánchez-Solís, Manuel

    2009-07-01

    Mutation epidemiology in each ethnic group is important for cystic fibrosis diagnosis and genetic counselling. To date, little has been reported on the prevalence of cystic fibrosis in the Ecuadorian population where the mutation distribution appears to differ from that of Europe. We present a series of four Ecuadorian patients homozygous for the H609R mutation in the CFTR gene. This is the first report of detection of this mutation in the Ecuadorian population. Taking advantage of the homozygous status of the patients, an evaluation of the most important clinical parameters is presented. From the diagnostic point of view, the information provided by our study is of relevance in designing an appropriate strategy for genetic testing of patients in Ecuador and in European countries where immigration from Ecuador is common.

  17. Inactivation of allergens and toxins.

    Science.gov (United States)

    Morandini, Piero

    2010-11-30

    Plants are replete with thousands of proteins and small molecules, many of which are species-specific, poisonous or dangerous. Over time humans have learned to avoid dangerous plants or inactivate many toxic components in food plants, but there is still room for ameliorating food crops (and plants in general) in terms of their allergens and toxins content, especially in their edible parts. Inactivation at the genetic rather than physical or chemical level has many advantages and classical genetic approaches have resulted in significant reduction of toxin content. The capacity, offered by genetic engineering, of turning off (inactivating) specific genes has opened up the possibility of altering the plant content in a far more precise manner than previously available. Different levels of intervention (genes coding for toxins/allergens or for enzymes, transporters or regulators involved in their metabolism) are possible and there are several tools for inactivating genes, both direct (using chemical and physical mutagens, insertion of transposons and other genetic elements) and indirect (antisense RNA, RNA interference, microRNA, eventually leading to gene silencing). Each level/strategy has specific advantages and disadvantages (speed, costs, selectivity, stability, reversibility, frequency of desired genotype and regulatory regime). Paradigmatic examples from classical and transgenic approaches are discussed to emphasize the need to revise the present regulatory process. Reducing the content of natural toxins is a trade-off process: the lesser the content of natural toxins, the higher the susceptibility of a plant to pests and therefore the stronger the need to protect plants. As a consequence, more specific pesticides like Bt are needed to substitute for general pesticides. Copyright © 2010 Elsevier B.V. All rights reserved.

  18. Dietary Iron Intake and Serum Ferritin Concentration in 213 Patients Homozygous for the HFEC282Y Hemochromatosis Mutation

    Directory of Open Access Journals (Sweden)

    Victor R Gordeuk

    2012-01-01

    Full Text Available BACKGROUND: HFEC282Y homozygotes have an increased risk for developing increased iron stores and related disorders. It is controversial whether dietary iron restrictions should be recommended to such individuals.

  19. Pulmonary Alveolar Microlithiasis with Homozygous c.316G>C (p.G106R) Mutation: A Case Report

    OpenAIRE

    Özbudak, İrem Hicran; Başsorgun, Cumhur İbrahim; Gülay ÖZBİLİM; LÜLECİ, Güven; Sarper, Alpay; Erdoğan, Abdullah; Taylan, Fulya; Altiok, Ender

    2012-01-01

    Pulmonary alveolar microlithiasis is characterized by the presence of calcospherites in alveolar spaces. Sporadic cases are more common, but the disease also presents in an inherited familial form. The greatest number of reported cases is from Europe and especially Turkey. We present a 43-year-old female with complaints of dyspnea for many years. She had a suspicious familial history of pulmonary alveolar microlithiasis. The surgical lung biopsy specimen appeared gritty and firm. Histological...

  20. A homozygous nonsense mutation in the methylmalonyl-CoA epimerase gene (MCEE) results in mild methylmalonic aciduria

    NARCIS (Netherlands)

    Bikker, H.; Bakker, H. D.; Abeling, N. G. G. M.; Poll-The, B. T.; Kleijer, W. J.; Rosenblatt, D. S.; Waterham, H. R.; Wanders, R. J. A.; Duran, M.

    2006-01-01

    Methylmalonic aciduria (MMA-uria) is an autosomal recessive inborn error of amino acid metabolism, involving valine, threonine, isoleucine, and methionine. This organic aciduria may present in the neonatal period with life-threatening metabolic acidosis, hyperammonemia, feeding difficulties,

  1. A homozygous mutation in HESX1 is associated with evolving hypopituitarism due to impaired repressor-corepressor interaction

    DEFF Research Database (Denmark)

    Carvalho, Luciani R; Woods, Kathryn S; Mendonca, Berenice B

    2003-01-01

    repressor domain (eh1) of HESX1, the first, to our knowledge, to be described in humans, in a girl with evolving combined pituitary hormone deficiency born to consanguineous parents. Neuroimaging revealed a thin pituitary stalk with anterior pituitary hypoplasia and an ectopic posterior pituitary...

  2. A new mutation in the CSB gene in a Chinese patient with mild Cockayne syndrome.

    Science.gov (United States)

    Luo, Yu; Ling, Yan; Chen, Jiachao; Xu, Xi; Chen, Chen; Leng, Fei; Cheng, Jing; Chen, Min; Lu, Zhiqiang

    2014-04-01

    Cockayne syndrome (CS) is a rare autosomal recessive genetic disease characterized by growth failure and progressive neurological degeneration. Here we report a mild form of CS patient who was homozygous for the C526T transition resulting in a new nonsense mutation, which converts Arg176 to a stop codon.

  3. Mutations in EXTL3 Cause Neuro-immuno-skeletal Dysplasia Syndrome

    NARCIS (Netherlands)

    Oud, M.M.; Tuijnenburg, P.; Hempel, M.; Vlies, N. van; Ren, Z.; Ferdinandusse, S.; Jansen, M.H.; Santer, R.; Johannsen, J.; Bacchelli, C.; Alders, M.; Li, R.; Davies, R.; Dupuis, L.; Cale, C.M.; Wanders, R.J.; Pals, S.T.; Ocaka, L.; James, C.; Muller, I.; Lehmberg, K.; Strom, T.; Engels, H.; Williams, H.J.; Beales, P.; Roepman, R.; Dias, P.; Brunner, H.G.; Cobben, J.M.; Hall, C.; Hartley, T.; Quesne Stabej, P. Le; Mendoza-Londono, R.; Davies, E.G.; Sousa, S.B.; Lessel, D.; Arts, H.H.; Kuijpers, T.W.

    2017-01-01

    EXTL3 regulates the biosynthesis of heparan sulfate (HS), important for both skeletal development and hematopoiesis, through the formation of HS proteoglycans (HSPGs). By whole-exome sequencing, we identified homozygous missense mutations c.1382C>T, c.1537C>T, c.1970A>G, and c.2008T>G in EXTL3 in

  4. High-resolution melting facilitates mutation screening of PYGM in patients with McArdle disease

    DEFF Research Database (Denmark)

    Duno, M.; Quinlivan, R.; Vissing, J.

    2009-01-01

    Mutations in PYGM, encoding the muscle-specific glycogen phosphorylase (myophosphorylase), are responsible for McArdle disease. Among Caucasians, a large proportion of patients are homozygous for the R50X mutation, but other mutations can affect all the 20 exons of PYGM, making mutation detection...... variations. Thirteen of these are pathogenic, and three were classified as polymorphisms. Nine variations had not previously been described. One of the novel mutations, c.2430C > T, was initially predicted to result in a silent G810G change, but cDNA analysis demonstrated that the mutation led to abnormal m...... laborious. We have developed a high-resolution melting (HRM) assay for mutation detection in PYGM. Twelve McArdle patients were investigated, in whom pre-screening had ruled out homozygosity or compound heterozygosity for the two common G205S and R50X mutations. In total, we identified 16 different...

  5. A frequent tyrosinase gene mutation associated with type I-A (tyroinase-negative) oculocutaneous albinism in Puerto Rico

    Energy Technology Data Exchange (ETDEWEB)

    Oetting, W.S.; Witkop, C.J. Jr.; Brown, S.A.; Fryer, J.P.; Bloom, K.E.; King, R.A. (Univ. of Minnesota, Minneapolis (United States)); Colomer, R. (Servicio Medico de Empressa de la ONCE, Canary Islands (Spain))

    1993-01-01

    The authors have determined the mutations in the tyrosinase gene from 12 unrelated Puerto Rican individuals who have type I-A (tyrosinase-negative) oculocutaneous albinism (OCA). All but one individual are of Hispanic descent. Nine individuals were homozygous for a missense mutation (G47D) in exon I at codon 47. Two individuals were heterozygous for the G47D mutation, with one having a missense mutation at codon 373 (T373K) in the homologous allele and the other having an undetermined mutation in the homologous allele. One individual with negroid features was homozygous for a nonsense mutation (W236X). The population migration between Puerto Rico and the Canary Islands is well recognized. Analysis of three individuals with OCA from the Canary Islands showed that one was a compound heterozygote for the G47D mutation and for a novel missense mutation (L216M), one was homozygous for a missense mutation (P81L), and one was heterozygous for the missense mutation P81L. The G47D and P81L missense mutations have been previously described in extended families in the United States. Haplotypes were determined using four polymorphisms linked to the tyrosinase locus. Haplotype analysis showed that the G47D mutation occurred on a single haplotype, consistent with a common founder for all individuals having this mutation. Two different haplotypes were found associated with the P81L mutation, suggesting that this may be either a recurring mutation for the tyrosinase gene or a recombination between haplotypes. 28 refs., 1 fig., 3 tabs.

  6. The gene TFR2 is mutated in a new type of haemochromatosis mapping to 7q22.

    Science.gov (United States)

    Camaschella, C; Roetto, A; Calì, A; De Gobbi, M; Garozzo, G; Carella, M; Majorano, N; Totaro, A; Gasparini, P

    2000-05-01

    Haemochromatosis is a common recessive disorder characterized by progressive iron overload, which may lead to severe clinical complications. Most patients are homozygous for the C282Y mutation in HFE on 6p (refs 1-5). A locus for juvenile haemochromatosis (HFE2) maps to 1q (ref. 7). Here we report a new locus (HFE3) on 7q22 and show that a homozygous nonsense mutation in the gene encoding transferrin receptor-2 (TFR2) is found in people with haemochromatosis that maps to HFE3.

  7. A novel PCCB mutation in a Thai patient with propionic acidemia identified by exome sequencing.

    Science.gov (United States)

    Porntaveetus, Thantrira; Srichomthong, Chalurmpon; Suphapeetiporn, Kanya; Shotelersuk, Vorasuk

    2015-01-01

    Propionic acidemia (PA) is an inborn error of metabolism, caused by mutations in either the PCCA or PCCB gene, leading to mitochondrial accumulation of propionyl-CoA and its by-products. Here we report a 6-year-old Thai boy with PA who was born to consanguineous parents. Exome sequencing identified a novel homozygous frameshift insertion (c.379_380insA; p.T127NfsX160) in the PCCB gene, expanding its mutational spectrum.

  8. Dystonia with Brain Manganese Accumulation Resulting From SLC30A10 Mutations: A New Treatable Disorder

    OpenAIRE

    Stamelou, Maria; Tuschl, Karin; Chong, W.K.; Andrew K. Burroughs; Mills, Philippa B.; Bhatia, Kailash P.; Clayton, Peter T.

    2012-01-01

    Background The first gene causing early-onset generalized dystonia with brain manganese accumulation has recently been identified. Mutations in the SLC30A10 gene, encoding a manganese transporter, cause a syndrome of hepatic cirrhosis, dystonia, polycythemia, and hypermanganesemia. Methods We present 10-year longitudinal clinical features, MRI data, and treatment response to chelation therapy of the originally described patient with a proven homozygous mutation in SLC30A10. Results The patien...

  9. CDH3 gene related hypotrichosis and juvenile macular dystrophy – A case with a novel mutation

    Directory of Open Access Journals (Sweden)

    Omer Karti

    2017-09-01

    Conclusions and importance: This case of HJMD was related to a novel homozygous mutation, termed c.447_467del (p.149_156del. These findings have significance for the future mutational analysis and genetic counseling of families with HJMD, particularly in our region. The presence of sparse hair in childhood, with or without limb anomalies, should alert clinicians to request an eye consultation. Pediatricians, dermatologists, and ophthalmologists should be aware of the rarely seen entity of juvenile macular dystrophy with hypotrichosis.

  10. Acute splenic sequestration in a pregnant woman with homozygous sickle-cell anemia

    Directory of Open Access Journals (Sweden)

    Carolina Bastos Maia

    Full Text Available CONTEXT Homozygous (SS sickle-cell anemia complicated by acute splenic sequestration in adults is a rare event, and it has never been reported during pregnancy. CASE REPORT A 25-year-old woman with homozygous (SS sickle-cell disease was hospitalized at 32 weeks' of gestation presenting weakness, abdominal pain, fever and hemoglobin of 2.4 g/dl. Abnormal fetal heart rate was detected by means of cardiotocography, and 5 units of packed red cells were transfused. Cesarean was performed at 37 weeks. Both mother and baby were discharged in a good general condition. CONCLUSION This case report demonstrates the importance of immediate blood transfusion for treatment of fetal distress in cases of splenic sequestration during pregnancy. This treatment is essential for avoiding maternal and fetal complications.

  11. Rapidly progressive atherosclerosis after domino liver transplantation from a teenage donor with homozygous familial hypercholesterolemia.

    Science.gov (United States)

    Golbus, Jessica R; Farhat, Linda; Fontana, Robert J; Rubenfire, Melvyn

    Familial hypercholesterolemia (FH) is an autosomal dominant disorder characterized by impaired clearance of low-density lipoprotein cholesterol. Given limitations in pharmacologic therapy and the significant morbidity and mortality associated with this disease, liver transplantation may be offered to select homozygous FH patients in childhood in an effort to slow progression of atherosclerotic cardiovascular disease. In rare cases, domino liver transplantation can be performed, transplanting the livers of patients with various metabolic disorders into elderly recipients whose projected survival precludes prolonged waiting on the transplant list. Herein, we report a case of domino liver transplantation using the liver of a 14-year-old boy with homozygous FH into a 65-year-old man with primary sclerosing cholangitis and cirrhosis who developed rapidly progressive atherosclerotic cardiovascular disease involving the arteries of his proximal bilateral lower extremities, carotid arteries and superior mesenteric artery. Copyright © 2017 National Lipid Association. Published by Elsevier Inc. All rights reserved.

  12. The Eag domain regulates the voltage-dependent inactivation of rat Eag1 K+ channels.

    Directory of Open Access Journals (Sweden)

    Ting-Feng Lin

    Full Text Available Eag (Kv10 and Erg (Kv11 belong to two distinct subfamilies of the ether-à-go-go K+ channel family (KCNH. While Erg channels are characterized by an inward-rectifying current-voltage relationship that results from a C-type inactivation, mammalian Eag channels display little or no voltage-dependent inactivation. Although the amino (N-terminal region such as the eag domain is not required for the C-type inactivation of Erg channels, an N-terminal deletion in mouse Eag1 has been shown to produce a voltage-dependent inactivation. To further discern the role of the eag domain in the inactivation of Eag1 channels, we generated N-terminal chimeras between rat Eag (rEag1 and human Erg (hERG1 channels that involved swapping the eag domain alone or the complete cytoplasmic N-terminal region. Functional analyses indicated that introduction of the homologous hERG1 eag domain led to both a fast phase and a slow phase of channel inactivation in the rEag1 chimeras. By contrast, the inactivation features were retained in the reverse hERG1 chimeras. Furthermore, an eag domain-lacking rEag1 deletion mutant also showed the fast phase of inactivation that was notably attenuated upon co-expression with the rEag1 eag domain fragment, but not with the hERG1 eag domain fragment. Additionally, we have identified a point mutation in the S4-S5 linker region of rEag1 that resulted in a similar inactivation phenotype. Biophysical analyses of these mutant constructs suggested that the inactivation gating of rEag1 was distinctly different from that of hERG1. Overall, our findings are consistent with the notion that the eag domain plays a critical role in regulating the inactivation gating of rEag1. We propose that the eag domain may destabilize or mask an inherent voltage-dependent inactivation of rEag1 K+ channels.

  13. Macular corneal dystrophy: mutational spectrum in German patients, novel mutations and therapeutic options.

    Science.gov (United States)

    Gruenauer-Kloevekorn, Claudia; Braeutigam, Saskia; Heinritz, Wolfram; Froster, Ursula G; Duncker, Gernot I W

    2008-10-01

    The objective of this study was to investigate genotype-phenotype correlations, the consequences for surgical treatment, and the therapeutical options in patients with macular corneal dystrophy (MCD). We investigated MCD genotype by using polymerase chain reaction followed by direct sequencing in one family and four patients with MCD. Results were confirmed by restriction analysis. Clinical phenotypes, histopathological findings, and therapeutical proceedings of each patient were reported and compared with the molecular genetic results. Five mutations, four missense mutations, and one frameshift mutation, from which three were novel, and one single-nucleotide polymorphism, were identified within the coding region of the CHST6 gene. In three patients, two with a homozygous mutation within the start codon (Met1Leu) and one with a heterozygous mutation (Leu200Arg) and a polymorphism (Arg162Gly), with irregular corneal surface and recurrent erosions a phototherapeutic keratectomy lead to a transient success. An additional fitting of rigid gas permeable contact lenses in one patient could further improve irregular astigmatism. In two patients, one with a frameshift mutation (1734_1735delTG; Arg211Gln) and one with two compound heterozygous mutations (Leu200Arg; Leu173Phe) and an additional polymorphism (Arg162Gly) a penetrating keratoplasty improved BCVA without any recurrence of the opacities within the follow-up time. Different genotypes imply several phenotypes, which influence therapeutical proceedings in MCD patients. Our study shows the wide range of diagnostic findings and therapeutical options in patients suffering from macular corneal dystrophy depending on the genotype.

  14. Suppression of cholesterol synthesis in cultured fibroblasts from a patient with homozygous familial hypercholesterolemia by her own low density lipoprotein density fraction. A possible role of apolipoprotein E

    NARCIS (Netherlands)

    Havekes, L.; Vermeer, B.J.; Wit, E. de

    1980-01-01

    The suppression of cellular cholesterol synthesis by low density lipoprotein (LDL) from a normal and from a homozygous familial hypercholesterolemic subject was measured on normal fibroblasts and on fibroblasts derived from the same homozygous familial hypercholesterolemic patient. On normal

  15. 5'UTR mutations of ENG cause hereditary hemorrhagic telangiectasia

    Directory of Open Access Journals (Sweden)

    Damjanovich Kristy

    2011-12-01

    Full Text Available Abstract Background Hereditary hemorrhagic telangiectasia (HHT is a vascular disorder characterized by epistaxis, arteriovenous malformations, and telangiectases. The majority of the patients have a mutation in the coding region of the activin A receptor type II-like 1 (ACVRL1 or Endoglin (ENG gene. However, in approximately 15% of cases, sequencing analysis and deletion/duplication testing fail to identify mutations in the coding regions of these genes. Knowing its vital role in transcription and translation control, we were prompted to investigate the 5'untranslated region (UTR of ENG. Methods and Results We sequenced the 5'UTR of ENG for 154 HHT patients without mutations in ENG or ACVRL1 coding regions. We found a mutation (c.-127C > T, which is predicted to affect translation initiation and alter the reading frame of endoglin. This mutation was found in a family with linkage to the ENG, as well as in three other patients, one of which had an affected sibling with the same mutation. In vitro expression studies showed that a construct with the c.-127C > T mutation alters the translation and decreases the level of the endoglin protein. In addition, a c.-9G > A mutation was found in three patients, one of whom was homozygous for this mutation. Expression studies showed decreased protein levels suggesting that the c.-9G > A is a hypomorphic mutation. Conclusions Our results emphasize the need for the inclusion of the 5'UTR region of ENG in clinical testing for HHT.

  16. Immunodeficiency associated with FCN3 mutation and ficolin-3 deficiency

    DEFF Research Database (Denmark)

    Munthe-Fog, Lea; Hummelshøj, Tina; Honoré, Christian

    2009-01-01

    Ficolin-3, encoded by the FCN3 gene and expressed in the lung and liver, is a recognition molecule in the lectin pathway of the complement system. Heterozygosity for an FCN3 frameshift mutation (rs28357092), leading to a distortion of the C-terminal end of the molecule, occurs in people without...... disease (allele frequency among whites, 0.01). We describe a patient with recurrent infections who was homozygous for this mutation, who had undetectable serum levels of ficolin-3, and who had a deficiency in ficolin-3-dependent complement activation....

  17. A Novel Mutation in Aspartoacylase Gene; Canavan Disease.

    Science.gov (United States)

    Ashrafi, Mahmoudreza; Tavasoli, Alireza; Katibeh, Pegah; Aryani, Omid; Vafaee-Shahi, Mohammad

    2015-01-01

    Objective Canavan disease (CD) is a type of vacuolating leukodystrophy with autosomal recessive inheritance. Aspartoacylase deficiency results in decrease of myelin biosynthesis, dysmyelination and brain edema. Although CD is a very common in Ashkenazi Jews patients, several cases have been reported from non-Jewish population. This report is based on a homozygous C.202G>A mutation in the ASPA gene identified from an Iranian patient. To our knowledge, this type of mutation has not been reported in non-Jewish population in the literature.

  18. MPL Baltimore mutation and thrombocytosis: case report and literature review.

    Science.gov (United States)

    Shkalim-Zemer, Vered; Dgany, Orly; Krasnov, Tanya; Yacobovich, Joanne; Tamary, Hannah

    2013-04-01

    Thrombocytosis is a common finding and is a frequent cause of referral for further investigation. The MPL Baltimore (Lys39Asn) mutation has been reported as a cause of thrombocytosis in 7% of African Americans. We describe an 11-month-old Ethiopian Jewish boy referred for evaluation of thrombocytosis who was found to be homozygous for MPL Baltimore. So far, there is no indication whether patients with thrombocytosis who have this mutation, particularly homozygotes, are at increased risk of thrombotic or hemorrhagic complications. Nevertheless, this entity should be considered in the differential diagnosis of every patient with thrombocytosis, particularly those of African origin.

  19. Clinical, Hematological and Molecular Analysis of Homozygous Hb E (HBB: c.79G > A) in the Indian Population.

    Science.gov (United States)

    Jayasree, Divya; Shaji, Ramachandran V; George, Biju; Mathews, Vikram; Srivastava, Alok; Edison, Eunice S

    2016-01-01

    Homozygous Hb E [β26(B8)Glu→Lys; HBB: c.79G > A] is a clinically mild disease with no significant symptoms. Very few studies are available on clinical variability in Hb E disorders. We report the profile of a series of homozygous Hb E patients in the Indian population. We analyzed various genetic factors that contribute to the heterogeneity in the phenotype of homozygous Hb E patients. Analysis of these parameters further enhances our understanding of the Hb E syndrome.

  20. Acute intermittent porphyria: studies of the severe homozygous dominant disease provides insights into the neurologic attacks in acute porphyrias.

    Science.gov (United States)

    Solis, Constanza; Martinez-Bermejo, Antonio; Naidich, Thomas P; Kaufmann, Walter E; Astrin, Kenneth H; Bishop, David F; Desnick, Robert J

    2004-11-01

    Acute intermittent porphyria (AIP), due to half-normal hydroxymethylbilane synthase activity,is characterized by acute life-threatening neurologic attacks whose etiology remains unclear. To date, only 3 patients confirmed to have homozygous dominant AIP (HD-AIP) have been described (hydroxymethylbilane synthase genotypes R167Q/R167Q and R167W/R173Q). To investigate the genetic, biochemical, clinical, and neuroradiologic features of a severely affected infant with HD-AIP. Clinical, imaging, and genotype/phenotype studies were performed. The proband, homoallelic for hydroxymethylbilane synthase mutation R167W, had approximately 1% of normal hydroxymethylbilane synthase activity, elevated porphyrins and porphyrin precursors, severe psychomotor delay, and central and peripheral neurologic manifestations. When expressed in vitro, the R167W mutant enzyme had less than 2% of normal activity but was markedly unstable, consistent with the proband's severe phenotype. Mitochondrial respiratory chain enzymes were normal. Neuroradiologic studies revealed a unique pattern of deep cerebral white matter injury, with relative preservation of the corpus callosum, anterior limb of the internal capsule, cerebral gray matter, and infratentorial structures. This severely affected patient with HD-AIP expanded the phenotypic spectrum of HD-AIP. His brain magnetic resonance imaging studies suggested selective cerebral oligodendrocyte postnatal involvement in HD-AIP, whereas most structures developed prenatally were intact. These findings indicate that the neurologic manifestations result from porphyrin precursor toxicity rather than heme deficiency and suggest that porphyrin precursor toxicity is primarily responsible for the acute neurologic attacks in heterozygous AIP and other porphyrias.

  1. Role of homozygous DC-SIGNR 5/5 tandem repeat polymorphism in HIV-1 exposed seronegative North Indian individuals.

    Science.gov (United States)

    Rathore, Anurag; Chatterjee, Animesh; Sivarama, P; Yamamoto, Naohiko; Dhole, Tapan N

    2008-01-01

    Despite multiple sexual exposures to HIV-1 virus, some individuals remain HIV-1 seronegative. Although several genetic factors have been related to HIV-1 resistance, the homozygosity for a mutation in CCR5 gene (the 32-bp deletion, i.e., CCR5-Delta32 allele) is presently considered the most relevant one. The C-type lectins, DC-SIGN (present on dendritic cells and macrophages) and DC-SIGNR (present on endothelial cells in liver and lymph nodes) efficiently bind and transmit HIV-1 to susceptible cell in trans, thereby augmenting the infection. A potential association of the DC-SIGN and DC-SIGNR neck domain repeat polymorphism and risk of HIV-1 infection is currently under debate. To determine the influence of host genetic factors on HIV-1 resistance, we conducted genetic risk association study in HIV-1-exposed seronegative (n = 47) individuals, HIV-1 seronegative (n = 262) healthy control, and HIV-1-infected seropositive patients (n = 168) for polymorphism in neck domain of DC-SIGN and DC-SIGNR genes. The DC-SIGN and DC-SIGNR genotypes were identified by polymerase chain reaction method in DNA extracted from peripheral blood and confirmed by sequencing. Fisher exact or chi (2) test was used for static analysis. DC-SIGN genotype and allele distribution was fairly similar in HIV-1-exposed seronegative, HIV-1 seropositive, and HIV-1 seronegative control. There was no statistical significance in the differences in the distribution of DC-SIGN genotypes. A total of 13 genotypes were found in DC-SIGNR neck repeat region polymorphism. Among all the genotypes, only 5/5 homozygous showed significant reduced risk of HIV-1 infection in HIV-1-exposed seronegative individuals (p = 0.009). A unique genotype 8/5 heterozygous was also found in HIV-1 seropositive individual, which is not reported elsewhere.

  2. Union makes strength: a worldwide collaborative genetic and clinical study to provide a comprehensive survey of RD3 mutations and delineate the associated phenotype.

    Directory of Open Access Journals (Sweden)

    Isabelle Perrault

    Full Text Available Leber congenital amaurosis (LCA is the earliest and most severe retinal degeneration (RD, and the most common cause of incurable blindness diagnosed in children. It is occasionally the presenting symptom of multisystemic ciliopathies which diagnosis will require a specific care of patients. Nineteen LCA genes are currently identified and three of them account for both non-syndromic and syndromic forms of the disease. RD3 (LCA12 was implicated as a LCA gene based on the identification of homozygous truncating mutations in two LCA families despite the screening of large cohorts of patients. Here we provide a comprehensive survey of RD3 mutations and of their clinical expression through the screening of a cohort of 852 patients originating worldwide affected with LCA or early-onset and severe RD. We identified three RD3 mutations in seven unrelated consanguineous LCA families - i.e., a 2 bp deletion and two nonsense mutations - predicted to cause complete loss of function. Five families originating from the Southern Shores of the Mediterranean segregated a similar mutation (c.112C>T, p.R38* suggesting that this change may have resulted from an ancient founder effect. Considering the low frequency of RD3 carriers, the recurrence risk for LCA in non-consanguineous unions is negligible for both heterozygote and homozygote RD3 individuals. The LCA12 phenotype in our patients is highly similar to those of patients with mutant photoreceptor-specific guanylate cyclase (GUCY2D/LCA1. This observation is consistent with the report of the role of RD3 in trafficking of GUCYs and gives further support to a common mechanism of photoreceptor degeneration in LCA12 and LCA1, i.e., inability to increase cytoplasmic cGMP concentration in outer segments and thus to recover the dark-state. Similar to LCA1, LCA12 patients have no extraocular symptoms despite complete inactivation of both RD3 alleles, supporting the view that extraocular investigations in LCA infants

  3. How much do we know about spontaneous human mutation rates

    Energy Technology Data Exchange (ETDEWEB)

    Crow, J.F. (Univ. of Wisconsin, Madison, WI (United States))

    1993-01-01

    The much larger number of cell divisions between zygote and sperm than between zygote and egg, the increased age of fathers of children with new dominant mutations, and the greater evolution rate of pseudogenes on the Y chromosome than of those on autosomes all point to a much higher mutation rate in human males than in females, as first pointed out by Haldane in his classical study of X-linked hemophilia. The age of the father is the main factor determining the human spontaneous mutation rate, and probably the total mutation rate. The total mutation rate in Drosophila males of genes causing minor reduction in viability is at least 0.4 per sperm and may be considerably higher. The great mutation load implied by a rate of [approx] 1 per zygote can be greatly ameliorated by quasi-transition selection. Corresponding data are not available for the human population. The evolution rate of pseudogenes in primates suggests some 10[sup 2] new mutations per zygote. Presumably the overwhelming majority of these are neutral, but even the approximate fraction is not known. Statistical evidence in Drosophilia shows that mutations with minor effects cause about the same heterozygous impairment of fitness as those that are lethal when homozygous. The magnitude of heterozygous effect is such that almost all mutant genes are eliminated as heterozygotes before ever becoming homozygous. Although quantitative data in the human species are lacking, anecdotal information supports the conclusion that partial dominance is the rule here as well. This suggests that if the human mutation rate were increased or decreased, the effects would be spread over a period of 50-100 generations. 31 refs., 3 figs., 2 tabs.

  4. Identification of MPL R102P Mutation in Hereditary Thrombocytosis

    Directory of Open Access Journals (Sweden)

    Christine Bellanné-Chantelot

    2017-09-01

    Full Text Available The molecular basis of hereditary thrombocytosis is germline mutations affecting the thrombopoietin (TPO/TPO receptor (MPL/JAK2 signaling axis. Here, we report one family presenting two cases with a mild thrombocytosis. By sequencing JAK2 and MPL coding exons, we identified a germline MPL R102P heterozygous mutation in the proband and his daughter. Concomitantly, we detected high TPO levels in the serum of these two patients. The mutation was not found in three other unaffected cases from the family except in another proband’s daughter who did not present thrombocytosis but had a high TPO level. The MPL R102P mutation was first described in congenital amegakaryocytic thrombocytopenia in a homozygous state with a loss-of-function activity. It was previously shown that MPL R102P was blocked in the endoplasmic reticulum without being able to translocate to the plasma membrane. Thus, this case report identifies for the first time that MPL R102P mutation can differently impact megakaryopoiesis: thrombocytosis or thrombocytopenia depending on the presence of the heterozygous or homozygous state, respectively. The paradoxical effect associated with heterozygous MPL R102P may be due to subnormal cell-surface expression of wild-type MPL in platelets inducing a defective TPO clearance. As a consequence, increased TPO levels may activate megakaryocyte progenitors that express a lower, but still sufficient level of MPL for the induction of proliferation.

  5. DNASE1L3 mutations in hypocomplementemic urticarial vasculitis syndrome.

    Science.gov (United States)

    Ozçakar, Z Birsin; Foster, Joseph; Diaz-Horta, Oscar; Kasapcopur, Ozgur; Fan, Yao-Shan; Yalçınkaya, Fatoş; Tekin, Mustafa

    2013-08-01

    Hypocomplementemic urticarial vasculitis syndrome (HUVS) is characterized by recurrent urticaria along with dermal vasculitis, arthritis, and glomerulonephritis. Systemic lupus erythematosus (SLE) develops in >50% of patients with HUVS, although the pathogenesis is unknown. The aim of this study was to identify the causative DNA mutations in 2 families with autosomal-recessive HUVS, in order to reveal the pathogenesis and facilitate the laboratory diagnosis. Autozygosity mapping was combined with whole-exome sequencing. In a family with 3 affected children, we identified a homozygous frameshift mutation, c.289_290delAC, in DNASE1L3. We subsequently identified another homozygous DNASE1L3 mutation leading to exon skipping, c.320+4delAGTA, in an unrelated family. The detected mutations led to loss of function, via either nonsense-mediated messenger RNA decay or abolished endonuclease activity, as demonstrated by a plasmid nicking assay. These results show that HUVS is caused by mutations in DNASE1L3, encoding an endonuclease that previously has been associated with SLE. Copyright © 2013 by the American College of Rheumatology.

  6. Normal X-inactivation mosaicism in corneas of heterozygous FlnaDilp2/+ female mice--a model of human Filamin A (FLNA diseases

    Directory of Open Access Journals (Sweden)

    Douvaras Panagiotis

    2012-02-01

    Full Text Available Abstract Background Some abnormalities of mouse corneal epithelial maintenance can be identified by the atypical mosaic patterns they produce in X-chromosome inactivation mosaics and chimeras. Human FLNA/+ females, heterozygous for X-linked, filamin A gene (FLNA mutations, display a range of disorders and X-inactivation mosaicism is sometimes quantitatively unbalanced. FlnaDilp2/+ mice, heterozygous for an X-linked filamin A (Flna nonsense mutation have variable eye, skeletal and other abnormalities, but X-inactivation mosaicism has not been investigated. The aim of this study was to determine whether X-inactivation mosaicism in the corneal epithelia of FlnaDilp2/+ mice was affected in any way that might predict abnormal corneal epithelial maintenance. Results X-chromosome inactivation mosaicism was studied in the corneal epithelium and a control tissue (liver of FlnaDilp2/+ and wild-type (WT female X-inactivation mosaics, hemizygous for the X-linked, LacZ reporter H253 transgene, using β-galactosidase histochemical staining. The corneal epithelia of FlnaDilp2/+ and WT X-inactivation mosaics showed similar radial, striped patterns, implying epithelial cell movement was not disrupted in FlnaDilp2/+ corneas. Corrected stripe numbers declined with age overall (but not significantly for either genotype individually, consistent with previous reports suggesting an age-related reduction in stem cell function. Corrected stripe numbers were not reduced in FlnaDilp2/+ compared with WT X-inactivation mosaics and mosaicism was not significantly more unbalanced in the corneal epithelia or livers of FlnaDilp2/+ than wild-type Flna+/+ X-inactivation mosaics. Conclusions Mosaic analysis identified no major effect of the mouse FlnaDilp2 mutation on corneal epithelial maintenance or the balance of X-inactivation mosaicism in the corneal epithelium or liver.

  7. Spectrum of mutations and phenotypic expression in patients with autosomal dominant hypercholesterolemia identified in Italy.

    Science.gov (United States)

    Bertolini, Stefano; Pisciotta, Livia; Rabacchi, Claudio; Cefalù, Angelo B; Noto, Davide; Fasano, Tommaso; Signori, Alessio; Fresa, Raffaele; Averna, Maurizio; Calandra, Sebastiano

    2013-04-01

    To determine the spectrum of gene mutations and the genotype-phenotype correlations in patients with Autosomal Dominant Hypercholesterolemia (ADH) identified in Italy. The resequencing of LDLR, PCSK9 genes and a selected region of APOB gene were conducted in 1018 index subjects clinically heterozygous ADH and in 52 patients clinically homozygous ADH. The analysis was also extended to 1008 family members of mutation positive subjects. Mutations were detected in 832 individuals: 97.4% with LDLR mutations, 2.2% with APOB mutations and 0.36% with PCSK9 mutations. Among the patients with homozygous ADH, 51 were carriers of LDLR mutations and one was an LDLR/PCSK9 double heterozygote. We identified 237 LDLR mutations (45 not previously reported), 4 APOB and 3 PCSK9 mutations. The phenotypic characterization of 1769 LDLR mutation carriers (ADH-1) revealed that in both sexes independent predictors of the presence of tendon xanthomas were age, the quintiles of LDL cholesterol, the presence of coronary heart disease (CHD) and of receptor negative mutations. Independent predictors of CHD were male gender, age, the presence of arterial hypertension, smoking, tendon xanthomas, the scalar increase of LDL cholesterol and the scalar decrease of HDL cholesterol. We identified 13 LDLR mutation clusters, which allowed us to compare the phenotypic impact of different mutations. The LDL cholesterol raising potential of these mutations was found to vary over a wide range. This study confirms the genetic and allelic heterogeneity of ADH and underscores that the variability in phenotypic expression of ADH-1 is greatly affected by the type of LDLR mutation. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  8. Genome-wide association study of N370S homozygous Gaucher disease reveals the candidacy of CLN8 gene as a genetic modifier contributing to extreme phenotypic variation.

    Science.gov (United States)

    Zhang, Clarence K; Stein, Philip B; Liu, Jun; Wang, Zuoheng; Yang, Ruhua; Cho, Judy H; Gregersen, Peter K; Aerts, Johannes M F G; Zhao, Hongyu; Pastores, Gregory M; Mistry, Pramod K

    2012-04-01

    Mutations in GBA1 gene result in defective acid β-glucosidase and the complex phenotype of Gaucher disease (GD) related to the accumulation of glucosylceramide-laden macrophages. The phenotype is highly variable even among patients harboring identical GBA1 mutations. We hypothesize that modifier gene(s) underlie phenotypic diversity in GD and performed a GWAS study in Ashkenazi Jewish patients with type 1 GD (GD1), homozygous for N370S mutation. Patients were assigned to mild, moderate, or severe disease categories using composite disease severity scoring systems. Whole-genome genotyping for >500,000 SNPs was performed to search for association signals using OQLS algorithm in 139 eligible patients. Several SNPs in linkage disequilibrium within the CLN8 gene locus were associated with the GD1 severity: SNP rs11986414 was associated with GD1 severity at P value 1.26 × 10(-6) . Compared to mild disease, risk allele A at rs11986414 conferred an odds ratio of 3.72 for moderate/severe disease. Loss of function mutations in CLN8 causes neuronal ceroid-lipofuscinosis, but our results indicate that its increased expression may protect against severe GD1. In cultured skin fibroblasts, the relative expression of CLN8 was higher in mild GD compared to severely affected patients, in whom CLN8 risk alleles were overrepresented. In an in vitro cell model of GD, CLN8 expression was increased, which was further enhanced in the presence of bioactive substrate, glucosylsphingosine. Taken together, CLN8 is a candidate modifier gene for GD1 that may function as a protective sphingolipid sensor and/or in glycosphingolipid trafficking. Future studies should explore the role of CLN8 in pathophysiology of GD. Copyright © 2012 Wiley Periodicals, Inc.

  9. Wilson disease mutation pattern with genotype-phenotype correlations from Western India: confirmation of p.C271* as a common Indian mutation and identification of 14 novel mutations.

    Science.gov (United States)

    Aggarwal, Annu; Chandhok, Gursimran; Todorov, Theodor; Parekh, Saloni; Tilve, Sharada; Zibert, Andree; Bhatt, Mohit; Schmidt, Hartmut H-J

    2013-07-01

    Wilson disease (WD) is an autosomal recessive disorder resulting from mutations in the ATP7B gene, with over 600 mutations described. Identification of mutations has made genetic diagnosis of WD feasible in many countries. The heterogeneity of ATP7B mutants is, however, yet to be identified in the Indian population. We analyzed the mutational pattern of WD in a large region of Western India. We studied patients (n = 52) for ATP7B gene mutations in a cohort of families with WD and also in first-degree relatives (n = 126). All 21 exon-intron boundaries of the WD gene were amplified and directly sequenced. We identified 36 different disease-causing mutations (31 exonic and five intronic splice site variants). Fourteen novel mutations were identified. Exons 2, 8, 13, 14, and 18 accounted for the majority of mutations (86.4%). A previously recognized mutation, p.C271*, and the novel mutation p.E122fs, were the most common mutations with allelic frequencies of 20.2% and 10.6%, respectively. Frequent homozygous mutations (58.9%) and disease severity assessments allowed analysis of genotype-phenotype correlations. Our study significantly adds to the emerging data from other parts of India suggesting that p.C271* may be the most frequent mutation across India, and may harbor a moderate to severely disabling phenotype with limited variability. © 2013 John Wiley & Sons Ltd/University College London.

  10. A Founder Mutation in MYO7A Underlies a Significant Proportion of Usher Syndrome in Indigenous South Africans: Implications for the African Diaspora.

    Science.gov (United States)

    Roberts, Lisa; George, Siddiqah; Greenberg, Jacquie; Ramesar, Raj S

    2015-10-01

    Research over the past 25 years at the University of Cape Town has led to the identification of causative mutations in 17% of the 1416 families in the Retinal Degenerative Diseases (RDD) biorepository in South Africa. A low rate of mutation detection has been observed in patients of indigenous African origin, hinting at novel genes and mutations in this population. Recently, however, data from our translational research program showed two unrelated indigenous African families with Usher syndrome (USH), with the same homozygous MYO7A mutation. Therefore, the extent to which this mutation contributes toward the disease burden in South Africa was investigated. Cohorts of unrelated indigenous South African probands with different RDD diagnoses were tested for the MYO7A c.6377delC mutation. Familial cosegregation analysis was performed for homozygous probands, clinical data were evaluated, and SNP haplotypes were analyzed. This homozygous MYO7A mutation underlies a remarkable 43% of indigenous African USH cases investigated in this study, the majority of which (60%) were diagnosed clinically with Type 2 USH. All homozygotes shared a common haplotype. This mutation does not appear to cause nonsyndromic vision loss. Of interest is the origin of this common mutation relevant to the Bantu population migration into southern Africa. Further investigation of the phenotype may elucidate the disease biology, and perhaps reveal a larger cohort with the same mutation, with which to assess the impact of environmental and genetic modifiers and evaluate therapeutic trials.

  11. Reduced rates of gene loss, gene silencing, and gene mutation in Dnmt1-deficient embryonic stem cells

    NARCIS (Netherlands)

    Chan, M.F.; van Amerongen, R.; Nijjar, T.; Cuppen, E.; Jones, P.A.; Laird, P.W.

    2001-01-01

    Tumor suppressor gene inactivation is a crucial event in oncogenesis. Gene inactivation mechanisms include events resulting in loss of heterozygosity (LOH), gene mutation, and transcriptional silencing. The contribution of each of these different pathways varies among tumor suppressor genes and by

  12. E-cadherin promotor methylation and mutation are inversely related to motility capacity of breast cancer cells

    NARCIS (Netherlands)

    Horssen, R. van; Hollestelle, A.; Rens, J.A.; Eggermont, A.M.; Schutte, M.; Ten Hagen, T.L.

    2012-01-01

    Inactivation of the tumor suppressor E-cadherin is an important event during breast tumorigenesis, as its decreased expression is linked to aggressiveness and metastasis. However, the relationship between the different modes of E-cadherin inactivation (mutation versus promotor hypermethylation) and

  13. Compound heterozygous ASPM mutations in Pakistani MCPH families

    DEFF Research Database (Denmark)

    Muhammad, Farooq; Mahmood Baig, Shahid; Hansen, Lars

    2009-01-01

    Autosomal recessive primary microcephaly (MCPH) is characterized by reduced head circumference (50% of all reported families. In spite of the high frequency of MCPH in Pakistan only one case of compound heterozygosity for mutations in ASPM has been reported yet. In this large MCPH study we...... confirmed compound heterozygosity in two and homozygous mutations in 20 families, respectively, showing that up to 10% of families with MCPH caused by ASPM are compound heterozygous. In total we identified 16 different nonsense or frameshift mutations of which 12 were novel thereby increasing the number...... of mutations in ASPM significantly from 35 to 47. We found no correlation between the severity of the condition and the site of truncation. We suggest that the high frequency of compound heterozygosity observed in this study is taken into consideration as part of future genetic testing and counseling...

  14. APC mutations in sporadic coloretal carcinomas from The Netherlands Cohort Study

    NARCIS (Netherlands)

    Lüchtenborg, M.; Weijenberg, M.P.; Roemen, G.M.J.M.; Bruïne, A.P. de; Brandt, P.A. van den; Lentjes, M.H.F.M.; Brink, M.; Engeland, M. van; Goldbohm, R.A.; Goeij, A.F.P.M. de

    2004-01-01

    The adenomatous polyposis coli (APC) gene is considered to be a gatekeeper in colorectal tumourigenesis. Inactivating mutations in APC have been reported in 34-70% of sporadic colorectal cancer patients, the majority of which occur in the mutation cluster region (MCR). In this study, tumour tissue

  15. Nonsense mutations in the shelterin complex genes ACD and TERF2IP in familial melanoma

    DEFF Research Database (Denmark)

    Aoude, Lauren G; Pritchard, Antonia L; Robles-Espinoza, Carla Daniela

    2015-01-01

    BACKGROUND: The shelterin complex protects chromosomal ends by regulating how the telomerase complex interacts with telomeres. Following the recent finding in familial melanoma of inactivating germline mutations in POT1, encoding a member of the shelterin complex, we searched for mutations in the...

  16. Highly prevalent LIPH founder mutations causing autosomal recessive woolly hair/hypotrichosis in Japan and the genotype/phenotype correlations.

    Directory of Open Access Journals (Sweden)

    Kana Tanahashi

    Full Text Available Mutations in LIPH cause of autosomal recessive woolly hair/hypotrichosis (ARWH, and the 2 missense mutations c.736T>A (p.Cys246Ser and c.742C>A (p.His248Asn are considered prevalent founder mutations for ARWH in the Japanese population. To reveal genotype/phenotype correlations in ARWH cases in Japan and the haplotypes in 14 Japanese patients from 14 unrelated Japanese families. 13 patients had woolly hair, and 1 patient had complete baldness since birth. An LIPH mutation search revealed homozygous c.736T>A mutations in 10 of the patients. Compound heterozygous c.736T>A and c.742C>A mutations were found in 3 of the patients, and homozygous c.742C>A mutation in 1 patient. The phenotype of mild hypotrichosis with woolly hair was restricted to the patients with the homozygous c.736T>A mutation. The severe phenotype of complete baldness was seen in only 1 patient with homozygous c.742C>A. Haplotype analysis revealed that the alleles containing the LIPH c.736T>A mutation had a haplotype identical to that reported previously, although 4 alleles out of 5 chromosomes containing the LIPH c.742C>A mutation had a different haplotype from the previously reported founder allele. These alleles with c.742C>A are thought to be the third founder LIPH mutation causing ARWH. To accurately determine the prevalence of the founder mutations, we investigated allele frequencies of those mutations in 819 Japanese controls. Heterozygous c.736T>A mutations were found in 13 controls (allele frequency: 0.0079; carrier rate: 0.016, and heterozygous c.742C>A mutations were found in 2 controls (allele frequency: 0.0012; carrier rate: 0.0024. In conclusion, this study confirms the more accurate allele frequencies of the pathogenic founder mutations of LIPH and shows that there is a third founder mutation in Japan. In addition, the present findings suggest that the mutation patterns of LIPH might be associated with hypotrichosis severity in ARWH.

  17. Whole exome sequencing in an Indian family links Coats plus syndrome and dextrocardia with a homozygous novel CTC1 and a rare HES7 variation.

    Science.gov (United States)

    Netravathi, Manjunath; Kumari, Renu; Kapoor, Saketh; Dakle, Pushkar; Dwivedi, Manish Kumar; Roy, Sumitabho Deb; Pandey, Paritosh; Saini, Jitender; Ramakrishna, Anil; Navalli, Devaraddi; Satishchandra, Parthasarathy; Pal, Pramod Kumar; Kumar, Arun; Faruq, Mohammed

    2015-02-10

    Coats plus syndrome is an autosomal recessive, pleiotropic, multisystem disorder characterized by retinal telangiectasia and exudates, intracranial calcification with leukoencephalopathy and brain cysts, osteopenia with predisposition to fractures, bone marrow suppression, gastrointestinal bleeding and portal hypertension. It is caused by compound heterozygous mutations in the CTC1 gene. We encountered a case of an eight-year old boy from an Indian family with manifestations of Coats plus syndrome along with an unusual occurrence of dextrocardia and situs inversus. Targeted resequencing of the CTC1 gene as well as whole exome sequencing (WES) were conducted in this family to identify the causal variations. The identified candidate variations were screened in ethnicity matched healthy controls. The effect of CTC1 variation on telomere length was assessed using Southern blot. A novel homozygous missense mutation c.1451A > C (p.H484P) in exon 9 of the CTC1 gene and a rare 3'UTR known dbSNP variation (c.*556 T > C) in HES7 were identified as the plausible candidates associated with this complex phenotype of Coats plus and dextrocardia. This CTC1 variation was absent in the controls and we also observed a reduced telomere length in the affected individual's DNA, suggesting its likely pathogenic nature. The reported p.H484P mutation is located in the N-terminal 700 amino acid regionthat is important for the binding of CTC1 to ssDNA through its two OB domains. WES data also showed a rare homozygous missense variation in the TEK gene in the affected individual. Both HES7 and TEK are targets of the Notch signaling pathway. This is the first report of a genetically confirmed case of Coats plus syndrome from India. By means of WES, the genetic variations in this family with unique and rare complex phenotype could be traced effectively. We speculate the important role of Notch signaling in this complex phenotypic presentation of Coats plus syndrome and dextrocardia

  18. Recent progress of national banking project on homozygous HLA-typed induced pluripotent stem cells in South Korea.

    Science.gov (United States)

    Rim, Yeri Alice; Park, Narae; Nam, Yoojun; Ham, Dong-Sik; Kim, Ji-Won; Ha, Hye-Yeong; Jung, Ji-Won; Jung, Seung Min; Baek, In Cheol; Kim, Su-Yeon; Kim, Tai-Gyu; Song, Jihwan; Lee, Jennifer; Park, Sung-Hwan; Chung, Nak-Gyun; Yoon, Kun-Ho; Ju, Ji Hyeon

    2017-09-23

    Induced pluripotent stem cells (iPSCs) can be generated by introducing several factors into mature somatic cells. Banking of iPSCs can lead to wider application for treatment and research. In an economical view, it is important to store cells that can cover a high percentage of the population. Therefore, the use of homozygous human leukocyte antigen-iPSCs (HLA-iPSCs) is thought as a potential candidate for effective iPSC banking system for further clinical use. We screened the database stored in the Catholic Hematopoietic Stem Cell Bank of Korea and sorted the most frequent homozygous HLA types of the South Korean population. Blood cells with the selected homozygous HLA types were obtained and transferred to the GMP facility in the Catholic Institute of Cell Therapy. Cells were reprogrammed to iPSCs inside the facility and went through several quality controls. As a result, a total of 13 homozygous GMP-grade iPSC lines were obtained in the facility. The generated iPSCs showed high pluripotency and normal karyotype after reprogramming. Five HLA-homozygous iPSCs had the type that was included in the top five most frequent HLA types. Homozygous HLA-iPSCs can open a new opportunity for further application of iPSCs in clinical research and therapy. Copyright © 2017 John Wiley & Sons, Ltd.

  19. MYO15A splicing mutations in hearing loss: A review literature and report of a novel mutation.

    Science.gov (United States)

    Motavaf, Mahsa; Soveizi, Mahdieh; Maleki, Majid; Mahdieh, Nejat

    2017-05-01

    Sensorineural hearing loss (SNHL) is the most prevalent genetic sensory defect in humans, affecting about 1 in 1000 newborns around the world. Non-syndromic SNHL accounts for nearly 70% of hereditary hearing loss and 80% of SNHL cases show an autosomal recessive mode of inheritance (ARNSHL). In the present study, we applied targeted-exome sequencing to a family with a single proband affected by congenital sensorineural hearing loss. 127 known genes were sequenced to find the causative mutation. One novel homozygous donor splice site mutation, c.4596 + 1G > A (IVS12 + 1G > A) was found in MYO15A gene. Analysis of this mutation within the family showed that the mutation segregates with hearing loss. New DNA sequencing technologies could lead to identification of the disease causing variants especially in highly heterogeneous disorders such as hearing loss. Copyright © 2017 Elsevier B.V. All rights reserved.

  20. A novel Werner Syndrome mutation: pharmacological treatment by read-through of nonsense mutations and epigenetic therapies.

    Science.gov (United States)

    Agrelo, Ruben; Sutz, Miguel Arocena; Setien, Fernando; Aldunate, Fabian; Esteller, Manel; Da Costa, Valeria; Achenbach, Ricardo

    2015-01-01

    Werner Syndrome (WS) is a rare inherited disease characterized by premature aging and increased propensity for cancer. Mutations in the WRN gene can be of several types, including nonsense mutations, leading to a truncated protein form. WRN is a RecQ family member with both helicase and exonuclease activities, and it participates in several cell metabolic pathways, including DNA replication, DNA repair, and telomere maintenance. Here, we reported a novel homozygous WS mutation (c.3767 C > G) in 2 Argentinian brothers, which resulted in a stop codon and a truncated protein (p.S1256X). We also observed increased WRN promoter methylation in the cells of patients and decreased messenger WRN RNA (WRN mRNA) expression. Finally, we showed that the read-through of nonsense mutation pharmacologic treatment with both aminoglycosides (AGs) and ataluren (PTC-124) in these cells restores full-length protein expression and WRN functionality.

  1. E-cadherin inactivation in lobular carcinoma in situ of the breast: an early event in tumorigenesis

    NARCIS (Netherlands)

    Vos, C. B.; Cleton-Jansen, A. M.; Berx, G.; de Leeuw, W. J.; ter Haar, N. T.; van Roy, F.; Cornelisse, C. J.; Peterse, J. L.; van de Vijver, M. J.

    1997-01-01

    In breast cancer, inactivating point mutations in the E-cadherin gene are frequently found in invasive lobular carcinoma (ILC) but never in invasive ductal carcinoma (IDC). Lobular carcinoma in situ (LCIS) adjacent to ILC has previously been shown to lack E-cadherin expression, but whether LCIS

  2. Novel DCX mutation-caused lissencephaly in a boy and very mild heterotopia in his mother.

    Science.gov (United States)

    Takeshita, Satoru; Higuchi, Machiko; Suyama, Megumi; Koide, Wakato; Maki, Kanemasa; Ushijima, Katsumi; Ban, Kyoko; Saito, Mariko; Kato, Mitsuhiro; Saitoh, Shinji

    2015-04-01

    We describe a novel mutation in DCX in a family in which a proband boy had classical lissencephaly and his mother had extremely mild subcortical band heterotopia. No factors that would make the mother's symptoms milder, such as somatic mosaicism or skewed X chromosome inactivation, were observed. From this family, we conclude that a DCX mutation causes a pleiotropic phenotype in the female even if X chromosome inactivation pattern is not skewed, and the novel missense mutation in DCX produced relatively mild dysfunction of the doublecortin protein. © 2015 Japan Pediatric Society.

  3. Additive effect of mutations in LDLR and PCSK9 genes on the phenotype of familial hypercholesterolemia.

    Science.gov (United States)

    Pisciotta, Livia; Priore Oliva, Claudio; Cefalù, Angelo Baldassare; Noto, Davide; Bellocchio, Antonella; Fresa, Raffaele; Cantafora, Alfredo; Patel, Dilip; Averna, Maurizio; Tarugi, Patrizia; Calandra, Sebastiano; Bertolini, Stefano

    2006-06-01

    Patients homozygous or compound heterozygous for LDLR mutations or double heterozygous for LDLR and apo B R3500Q mutation have higher LDL-C levels, more extensive xanthomatosis and more severe premature coronary disease (pCAD) than simple heterozygotes for mutations in either these genes or for missense mutations in PCSK9 gene. It is not known whether combined mutations in LDLR and PKCS9 are associated with such a severe phenotype. We sequenced Apo B and PCSK9 genes in two patients with the clinical diagnosis of homozygous FH who were heterozygous for LDLR gene mutations. Proband Z.P. (LDL-C 13.39 mmol/L and pCAD) was heterozygous for an LDLR mutation (p.E228K) inherited from her father (LDL-C 8.07 mmol/L) and a PCSK9 mutation (p.R496W) from her mother (LDL-C 5.58 mmol/L). Proband L.R. and her sister (LDL-C 11.51 and 10.47 mmol/L, xanthomatosis and carotid atherosclerosis) were heterozygous for an LDLR mutation (p.Y419X) inherited from their mother (LDL-C 6.54 mmol/L) and a PCSK9 mutation (p.N425S) probably from their deceased father. The LDL-C levels in double heterozygotes of these two families were 56 and 44% higher than those found in simple heterozygotes for the two LDLR mutations, respectively. The two PCSK9 mutations are novel and were not found in 110 controls and 80 patients with co-dominant hypercholesterolemia. These observations indicate that rare missense mutations of PCSK9 may worsen the clinical phenotype of patients carrying LDLR mutations.

  4. Enhanced vulnerability of human proteins towards disease-associated inactivation through divergent evolution.

    Science.gov (United States)

    Medina-Carmona, Encarnación; Fuchs, Julian E; Gavira, Jose A; Mesa-Torres, Noel; Neira, Jose L; Salido, Eduardo; Palomino-Morales, Rogelio; Burgos, Miguel; Timson, David J; Pey, Angel L

    2017-09-15

    Human proteins are vulnerable towards disease-associated single amino acid replacements affecting protein stability and function. Interestingly, a few studies have shown that consensus amino acids from mammals or vertebrates can enhance protein stability when incorporated into human proteins. Here, we investigate yet unexplored relationships between the high vulnerability of human proteins towards disease-associated inactivation and recent evolutionary site-specific divergence of stabilizing amino acids. Using phylogenetic, structural and experimental analyses, we show that divergence from the consensus amino acids at several sites during mammalian evolution has caused local protein destabilization in two human proteins linked to disease: cancer-associated NQO1 and alanine:glyoxylate aminotransferase, mutated in primary hyperoxaluria type I. We demonstrate that a single consensus mutation (H80R) acts as a disease suppressor on the most common cancer-associated polymorphism in NQO1 (P187S). The H80R mutation reactivates P187S by enhancing FAD binding affinity through local and dynamic stabilization of its binding site. Furthermore, we show how a second suppressor mutation (E247Q) cooperates with H80R in protecting the P187S polymorphism towards inactivation through long-range allosteric communication within the structural ensemble of the protein. Our results support that recent divergence of consensus amino acids may have occurred with neutral effects on many functional and regulatory traits of wild-type human proteins. However, divergence at certain sites may have increased the propensity of some human proteins towards inactivation due to disease-associated mutations and polymorphisms. Consensus mutations also emerge as a potential strategy to identify structural hot-spots in proteins as targets for pharmacological rescue in loss-of-function genetic diseases. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please

  5. Hematological and Molecular Characterization of a Novel Hb A2 Variant with Homozygous α-Thalassemia-2 in a Southern Thai Individual.

    Science.gov (United States)

    Nuinoon, Manit; Jeenduang, Nutjaree; Kesornsit, Aumpika; Horpet, Dararat; Plyduang, Thunyaluk

    2017-05-01

    We report here the hematological and molecular features of a novel δ-globin chain variant found in a Southern Thai woman. Her complete blood count was as follows: red blood cell (RBC) count 5.90 × 10(12)/L, hemoglobin concentration (Hb) 12.6 g/dL, packed cell volume (PCV) 0.41 L/L, mean corpuscular volume (MCV) 69.5 fL, mean corpuscular Hb (MCH) 21.4 pg, mean corpuscular Hb concentration (MCHC) 30.7 g/dL and RBC distribution width (RDW) 13.1%. The blood smear demonstrated microcytic hypochromic RBCs suggestive of thalassemia trait. Hemoglobin analysis identified Hb A2 + Hb A2-Kiriwong (2.4%) and Hb F (0.1%) on high performance liquid chromatography (HPLC). To characterize the α-thalassemia (α-thal) genotype, common α-thal-1 and α-thal-2 alleles were characterized by multiplex gap-polymerase chain reaction (gap-PCR). The results revealed homozygous α-thal-2 (-α(3.7)/-α(3.7)) in this case. DNA sequencing showed the presence of a novel δ-globin gene mutation [δ77(EF1)His→Arg; HBD: c.233A>G] that we named Hb A2-Kiriwong for the village from where the proband lived. In summary, the presence of microcytic hypochromic RBCs in this case was likely the result of the homozygous -α(3.7) (rightward) deletion and was not affected by this Hb A2 variant.

  6. Analysis of a new homozygous deletion in the tumor suppressor region at 3p12.3 reveals two novel intronic noncoding RNA genes.

    Science.gov (United States)

    Angeloni, Debora; ter Elst, Arja; Wei, Ming Hui; van der Veen, Anneke Y; Braga, Eleonora A; Klimov, Eugene A; Timmer, Tineke; Korobeinikova, Luba; Lerman, Michael I; Buys, Charles H C M

    2006-07-01

    Homozygous deletions or loss of heterozygosity (LOH) at human chromosome band 3p12 are consistent features of lung and other malignancies, suggesting the presence of a tumor suppressor gene(s) (TSG) at this location. Only one gene has been cloned thus far from the overlapping region deleted in lung and breast cancer cell lines U2020, NCI H2198, and HCC38. It is DUTT1 (Deleted in U Twenty Twenty), also known as ROBO1, FLJ21882, and SAX3, according to HUGO. DUTT1, the human ortholog of the fly gene ROBO, has homology with NCAM proteins. Extensive analyses of DUTT1 in lung cancer have not revealed any mutations, suggesting that another gene(s) at this location could be of importance in lung cancer initiation and progression. Here, we report the discovery of a new, small, homozygous deletion in the small cell lung cancer (SCLC) cell line GLC20, nested in the overlapping, critical region. The deletion was delineated using several polymorphic markers and three overlapping P1 phage clones. Fiber-FISH experiments revealed the deletion was approximately 130 kb. Comparative genomic sequence analysis uncovered short sequence elements highly conserved among mammalian genomes and the chicken genome. The discovery of two EST clusters within the deleted region led to the isolation of two noncoding RNA (ncRNA) genes. These were subsequently found differentially expressed in various tumors when compared to their normal tissues. The ncRNA and other highly conserved sequence elements in the deleted region may represent miRNA targets of importance in cancer initiation or progression. Published 2006 Wiley-Liss, Inc.

  7. Confirmation that RIPK4 mutations cause not only Bartsocas-Papas syndrome but also CHAND syndrome.

    Science.gov (United States)

    Busa, Tiffany; Jeraiby, Mohammed; Clémenson, Alix; Manouvrier, Sylvie; Granados, Viviana; Philip, Nicole; Touraine, Renaud

    2017-09-21

    CHAND syndrome is an autosomal recessive disorder characterized by curly hair, ankyloblepharon, and nail dysplasia. Only few patients were reported to date. A homozygous RIPK4 mutation was recently identified by homozygosity mapping and whole exome sequencing in three patients from an expanded consanguineous kindred with a clinical diagnosis of CHAND syndrome. RIPK4 was previously known to be implicated in Bartsocas-Papas syndrome, the autosomal recessive form of popliteal pterygium syndrome. We report here two cases of RIPK4 homozygous mutations in a fetus with severe Bartsocas-Papas syndrome and a patient with CHAND syndrome. The patient with CHAND syndrome harbored the same mutation as the one identified in the family previously reported. We thus confirm the implication of RIPK4 gene in CHAND syndrome in addition to Bartsocas-Papas syndrome and discuss genotype/phenotype correlations. © 2017 Wiley Periodicals, Inc.

  8. Neonatal multiple sulfatase deficiency with a novel mutation and review of the literature.

    Science.gov (United States)

    Nur, Banu Güzel; Mıhçı, Ercan; Pepe, Stefano; Biberoğlu, Gürsel; Ezgü, Fatih Süheyl; Ballabio, Andrea; Öztekin, Osman; Dursun, Oğuz

    2014-01-01

    Multiple sulfatase deficiency is a rare autosomal recessive disorder in which affected individuals present a complex phenotype due to the impaired activity of all sulfatases. There are different types of multiple sulfatase deficiency; among them, the neonatal form is the most severe, with a broad range of mucopolysaccharidosis-like symptoms and death within the first year of life. The disorder is caused by homozygous or compound heterozygous mutations in the sulfatase-modifying factor-1 (SUMF1) gene. In this article, we describe a non-ichthyotic neonatal multiple sulfatase deficiency patient with a novel mutation in the SUMF1 gene. The missense mutation c.777C>G, for which the patient was homozygous, had been caused by a p.N259K amino acid substitution. We evaluated the patient using clinical findings, neuroimaging studies and molecular analysis via the literature; we also wanted to note the difficulties in the diagnosis of this rare disease.

  9. Corneal arcus and xanthomas in homozygous familial hypercholesterolemia: First report from China

    Directory of Open Access Journals (Sweden)

    Xin Meng

    2013-01-01

    Full Text Available We report the case of a 12-year-old male who developed corneal arcus and multiple skin lesions with a 10-year history of xanthomas. The lesions appeared over his fingers, hands, elbows, knees, buttocks and feet. Laboratory studies showed a total serum cholesterol level of 752.1 mg/dL; a triglyceride level of 96.6 mg/dL; a low-density lipoprotein cholesterol level of 661.3 mg/dL. Findings were consistent with homozygous familial hypercholesterolemia. To our knowledge, this is the first such case to be reported from China.

  10. Mutations and epimutations in the origin of cancer

    Energy Technology Data Exchange (ETDEWEB)

    Peltomaeki, Paeivi, E-mail: Paivi.Peltomaki@Helsinki.Fi

    2012-02-15

    Cancer is traditionally viewed as a disease of abnormal cell proliferation controlled by a series of mutations. Mutations typically affect oncogenes or tumor suppressor genes thereby conferring growth advantage. Genomic instability facilitates mutation accumulation. Recent findings demonstrate that activation of oncogenes and inactivation of tumor suppressor genes, as well as genomic instability, can be achieved by epigenetic mechanisms as well. Unlike genetic mutations, epimutations do not change the base sequence of DNA and are potentially reversible. Similar to genetic mutations, epimutations are associated with specific patterns of gene expression that are heritable through cell divisions. Knudson's hypothesis postulates that inactivation of tumor suppressor genes requires two hits, with the first hit occurring either in somatic cells (sporadic cancer) or in the germline (hereditary cancer) and the second one always being somatic. Studies on hereditary and sporadic forms of colorectal carcinoma have made it evident that, apart from genetic mutations, epimutations may serve as either hit or both. Furthermore, recent next-generation sequencing studies show that epigenetic genes, such as those encoding histone modifying enzymes and subunits for chromatin remodeling systems, are themselves frequent targets of somatic mutations in cancer and can act like tumor suppressor genes or oncogenes. This review discusses genetic vs. epigenetic origin of cancer, including cancer susceptibility, in light of recent discoveries. Situations in which mutations and epimutations occur to serve analogous purposes are highlighted.

  11. Photodynamic Inactivation of Mammalian Viruses and Bacteriophages

    Directory of Open Access Journals (Sweden)

    Liliana Costa

    2012-06-01

    Full Text Available Photodynamic inactivation (PDI has been used to inactivate microorganisms through the use of photosensitizers. The inactivation of mammalian viruses and bacteriophages by photosensitization has been applied with success since the first decades of the last century. Due to the fact that mammalian viruses are known to pose a threat to public health and that bacteriophages are frequently used as models of mammalian viruses, it is important to know and understand the mechanisms and photodynamic procedures involved in their photoinactivation. The aim of this review is to (i summarize the main approaches developed until now for the photodynamic inactivation of bacteriophages and mammalian viruses and, (ii discuss and compare the present state of the art of mammalian viruses PDI with phage photoinactivation, with special focus on the most relevant mechanisms, molecular targets and factors affecting the viral inactivation process.

  12. Long-term p110? PI3K inactivation exerts a beneficial effect on metabolism

    OpenAIRE

    Foukas, Lazaros C; Bilanges, Benoit; Bettedi, Lucia; Pearce, Wayne; Ali, Khaled; Sancho, Sara; Withers, Dominic J.; Vanhaesebroeck, Bart

    2013-01-01

    The insulin/insulin-like growth factor-1 signalling (IIS) pathway regulates cellular and organismal metabolism and controls the rate of aging. Gain-of-function mutations in p110?, the principal mammalian IIS-responsive isoform of PI 3-kinase (PI3K), promote cancer. In contrast, loss-of-function mutations in p110? impair insulin signalling and cause insulin resistance, inducing a pre-diabetic state. It remains unknown if long-term p110? inactivation induces further metabolic deterioration over...

  13. Medium-chain acyl-CoA dehydrogenase (MCAD) mutations identified by MS/MS-based prospective screening of newborns differ from those observed in patients with clinical symptoms

    DEFF Research Database (Denmark)

    Andresen, B S; Dobrowolski, S F; O'Reilly, L

    2001-01-01

    Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most frequently diagnosed mitochondrial beta-oxidation defect, and it is potentially fatal. Eighty percent of patients are homozygous for a common mutation, 985A-->G, and a further 18% have this mutation in only one disease allele...

  14. Mutation analysis of SLC26A4 for Pendred syndrome and nonsyndromic hearing loss by high-resolution melting

    DEFF Research Database (Denmark)

    Chen, Neng; Tranebjærg, Lisbeth; Rendtorff, Nanna Dahl

    2011-01-01

    to identify mutations for individual patients. Although Sanger sequencing is the gold standard for mutation detection, screening methods supplemented with targeted sequencing can provide a cost-effective alternative. One such method, denaturing high-performance liquid chromatography, was developed...... for clinical mutation detection in SLC26A4. However, this method inherently cannot distinguish homozygous changes from wild-type sequences. High-resolution melting (HRM), on the other hand, can detect heterozygous and homozygous changes cost-effectively, without any post-PCR modifications. We developed...... a closed-tube HRM mutation detection method specific for SLC26A4 that can be used in the clinical diagnostic setting. Twenty-eight primer pairs were designed to cover all 21 SLC26A4 exons and splice junction sequences. Using the resulting amplicons, initial HRM analysis detected all 45 variants previously...

  15. A Naturally Occurring hPMS2 Mutation Can Confer a Dominant Negative Mutator Phenotype

    Science.gov (United States)

    Nicolaides, Nicholas C.; Littman, Susan J.; Modrich, Paul; Kinzler, Kenneth W.; Vogelstein, Bert

    1998-01-01

    Defects in mismatch repair (MMR) genes result in a mutator phenotype by inducing microsatellite instability (MI), a characteristic of hereditary nonpolyposis colorectal cancers (HNPCC) and a subset of sporadic colon tumors. Present models describing the mechanism by which germ line mutations in MMR genes predispose kindreds to HNPCC suggest a “two-hit” inactivation of both alleles of a particular MMR gene. Here we present experimental evidence that a nonsense mutation at codon 134 of the hPMS2 gene is sufficient to reduce MMR and induce MI in cells containing a wild-type hPMS2 allele. These results have significant implications for understanding the relationship between mutagenesis and carcinogenesis and the ability to generate mammalian cells with mutator phenotypes. PMID:9488480

  16. Low frequency of Parkin, Tyrosine Hydroxylase, and GTP Cyclohydrolase I gene mutations in a Danish population of early-onset Parkinson's Disease

    DEFF Research Database (Denmark)

    Hertz, Jens Michael; Ostergaard, K; juncker, Inger

    2006-01-01

    Autosomal recessive Parkinson's disease (PD) with early-onset may be caused by mutations in the parkin gene (PARK2). We have ascertained 87 Danish patients with an early-onset form of PD (age at onset ... mutation and a missense mutation (A6T) in TH of unknown significance. It cannot be excluded that both mutations contribute to the phenotype. No other putative disease causing TH or GCH1 mutations were found. In conclusion, homozygous, or compound heterozygous PARK2 mutations, and mutations in GCH1 and TH...... to determine the frequency of PARK2 mutations. Analysis of the GTP cyclohydrolase I gene (GCH1) and the tyrosine hydroxylase gene (TH), mutated in dopa-responsive dystonia and juvenile PD, have also been included. Ten different PARK2 mutations were identified in 10 patients. Two of the patients (2.3%) were...

  17. Case report: a novel KERA mutation associated with cornea plana and its predicted effect on protein function

    DEFF Research Database (Denmark)

    Roos, Laura; Bertelsen, Birgitte; Harris, Pernille

    2015-01-01

    individuals, hypotrichosis was found. KERA was screened for mutations using Sanger sequencing. We detected a novel KERA variant, p.(Ile225Thr), that segregates with the disease in the homozygous form. The three-dimensional structure of keratocan protein was modelled, and we showed that this missense variation...

  18. Mutations in RAB28, encoding a farnesylated small GTPase, are associated with autosomal-recessive cone-rod dystrophy

    NARCIS (Netherlands)

    Roosing, S.; Rohrschneider, K.; Beryozkin, A.; Sharon, D.; Weisschuh, N.; Staller, J.; Kohl, S.; Zelinger, L.; Peters, T.A.; Neveling, K.; Strom, T.M.; Disease, C. European Retina; Born, L.I. van den; Hoyng, C.B.; Klaver, C.C.; Roepman, R.; Wissinger, B.; Banin, E.; Cremers, F.P.M.; Hollander, A.I. den

    2013-01-01

    The majority of the genetic causes of autosomal-recessive (ar) cone-rod dystrophy (CRD) are currently unknown. A combined approach of homozygosity mapping and exome sequencing revealed a homozygous nonsense mutation (c.565C>T [p.Glu189*]) in RAB28 in a German family with three siblings with

  19. Heart-specific expression of laminopathic mutations in transgenic zebrafish.

    Science.gov (United States)

    Verma, Ajay D; Parnaik, Veena K

    2017-07-01

    Lamins are key determinants of nuclear organization and function in the metazoan nucleus. Mutations in human lamin A cause a spectrum of genetic diseases that affect cardiac muscle and skeletal muscle as well as other tissues. A few laminopathies have been modeled using the mouse. As zebrafish is a well established model for the study of cardiac development and disease, we have investigated the effects of heart-specific lamin A mutations in transgenic zebrafish. We have developed transgenic lines of zebrafish expressing conserved lamin A mutations that cause cardiac dysfunction in humans. Expression of zlamin A mutations Q291P and M368K in the heart was driven by the zebrafish cardiac troponin T2 promoter. Homozygous mutant embryos displayed nuclear abnormalities in cardiomyocyte nuclei. Expression analysis showed the upregulation of genes involved in heart regeneration in transgenic mutant embryos and a cell proliferation marker was increased in adult heart tissue. At the physiological level, there was deviation of up to 20% from normal heart rate in transgenic embryos expressing mutant lamins. Adult homozygous zebrafish were fertile and did not show signs of early mortality. Our results suggest that transgenic zebrafish models of heart-specific laminopathies show cardiac regeneration and moderate deviations in heart rate during embryonic development. © 2017 International Federation for Cell Biology.

  20. A homozygous deletion in GRID2 causes a human phenotype with cerebellar ataxia and atrophy.

    Science.gov (United States)

    Utine, G Eda; Haliloğlu, Göknur; Salanci, Bilge; Çetinkaya, Arda; Kiper, P Özlem; Alanay, Yasemin; Aktas, Dilek; Boduroğlu, Koray; Alikaşifoğlu, Mehmet

    2013-07-01

    GRID2 is a member of the ionotropic glutamate receptor family of excitatory neurotransmitter receptors. GRID2 encodes the glutamate receptor subunit delta-2, selectively expressed in cerebellar Purkinje cells. The phenotype associated with loss of GRID2 function was described only in mice until now, characterized by different degrees of cerebellar ataxia and usually relatively mild abnormalities of the cerebellum. This work describes for the first time the human phenotype associated with homozygous partial deletion of GRID2 in 3 children in one large consanguineous Turkish family. Homozygous deletion of exons 3 and 4 of GRID2 (94 153 589-94 298 037 bp) in the proband and similarly affected cousins, and heterozygous deletions in parental DNA were shown using Affymetrix® 6.0 single-nucleotide polymorphism array, confirmed by real-time polymerase chain reaction. The phenotype includes nystagmus, hypotonia with marked developmental delay in gross motor skills in early infancy followed by a static encephalopathy course with development of cerebellar ataxia, oculomotor apraxia, and pyramidal tract involvement.

  1. ChopSticks: High-resolution analysis of homozygous deletions by exploiting concordant read pairs.

    Science.gov (United States)

    Yasuda, Tomohiro; Suzuki, Shin; Nagasaki, Masao; Miyano, Satoru

    2012-10-30

    Structural variations (SVs) in genomes are commonly observed even in healthy individuals and play key roles in biological functions. To understand their functional impact or to infer molecular mechanisms of SVs, they have to be characterized with the maximum resolution. However, high-resolution analysis is a difficult task because it requires investigation of the complex structures involved in an enormous number of alignments of next-generation sequencing (NGS) reads and genome sequences that contain errors. We propose a new method called ChopSticks that improves the resolution of SV detection for homozygous deletions even when the depth of coverage is low. Conventional methods based on read pairs use only discordant pairs to localize the positions of deletions, where a discordant pair is a read pair whose alignment has an aberrant strand or distance. In contrast, our method exploits concordant reads as well. We theoretically proved that when the depth of coverage approaches zero or infinity, the expected resolution of our method is asymptotically equal to that of methods based only on discordant pairs under double coverage. To confirm the effectiveness of ChopSticks, we conducted computational experiments against both simulated NGS reads and real NGS sequences. The resolution of deletion calls by other methods was significantly improved, thus demonstrating the usefulness of ChopSticks. ChopSticks can generate high-resolution deletion calls of homozygous deletions using information independent of other methods, and it is therefore useful to examine the functional impact of SVs or to infer SV generation mechanisms.

  2. Polyhydramnios, megalencephaly and symptomatic epilepsy caused by a homozygous 7-kilobase deletion in LYK5.

    Science.gov (United States)

    Puffenberger, Erik G; Strauss, Kevin A; Ramsey, Keri E; Craig, David W; Stephan, Dietrich A; Robinson, Donna L; Hendrickson, Christine L; Gottlieb, Steven; Ramsay, David A; Siu, Victoria M; Heuer, Gregory G; Crino, Peter B; Morton, D Holmes

    2007-07-01

    We used single nucleotide polymorphism (SNP) microarrays to investigate the cause of a symptomatic epilepsy syndrome in a group of seven distantly related Old Order Mennonite children. Autozygosity mapping was inconclusive, but closer inspection of the data followed by formal SNP copy number analyses showed that all affected patients had homozygous deletions of a single SNP (rs721575) and their parents were hemizygous for this marker. The deleted SNP marked a larger deletion encompassing exons 9-13 of LYK5, which encodes STE20-related adaptor protein, a pseudokinase necessary for proper localization and function of serine/threonine kinase 11 (a.k.a. LKB1). Homozygous LYK5 deletions were associated with polyhydramnios, preterm labour and distinctive craniofacial features. Affected children had large heads, infantile-onset intractable multifocal seizures and severe psychomotor retardation. We designated this condition PMSE syndrome (polyhydramnios, megalencephaly and symptomatic epilepsy). Thirty-eight percent (N = 16) of affected children died during childhood (ages 7 months to 6 years) from medical complications of the disorder, which included status epilepticus, congestive heart failure due to atrial septal defect and hypernatremic dehydration due to diabetes insipidus. A single post-mortem neuropathological study revealed megalencephaly, ventriculomegaly, cytomegaly and extensive vacuolization and astrocytosis of white matter. There was abundant anti-phospho-ribosomal S6 labelling of large cells within the frontal cortex, basal ganglia, hippocampus and spinal cord, consistent with constitutive activation of the mammalian target of rapamycin (mTOR) signalling pathway in brain.

  3. Heart valve surgery in patients with homozygous sickle cell disease: A management strategy

    Directory of Open Access Journals (Sweden)

    El Mehdi Moutaouekkil

    2015-01-01

    Full Text Available Background: Patients with the homozygous sickle cell disease have increased perioperative mortality. Some indications like heart valve surgery, may justify an exchange blood transfusion to reduce the proportion of hemoglobin S (HbS and complications. Subjects and Methods: We report two female cases aged 20 and 27, of African origin with homozygous sickle cell anemia who underwent heart valve surgery to treat mitral valve regurgitation. This presentation describes the perioperative considerations including anesthesia and postoperative care. Results: A partial exchange blood transfusion decreased HbS levels from respectively, 90% and 84%, 9% to 27% and 34%, and simultaneously treated the anemia. Neither sickling crisis nor acidosis occurred in any patient, and no special postoperative complication occurred. Average hospital stay was 10 days. Currently, the two patients remain alive and free of cardiac symptoms. Discussion: Although the presence of sickle cell disorders is associated with increased risk of sickling and thus vaso-occlusive complications, they should not be taken as a contraindication for heart valve surgery. Nevertheless, monitoring of certain parameters such as venous, arterial oxygen content, pH, and body temperature is mandatory for a better outcome. Furthermore, preoperative exchange transfusion has a positive influence on the outcome of surgery and on the survival of patients undergoing heart valves surgery. Avoiding intraoperative hypoxia, hypothermia, and vaso-constrictive agents, minimizing HbS levels with preoperative exchange transfusion, and ensuring a stress-free environment with the judicious use of sedatives made surgery relatively safe in these cases.

  4. Heart valve surgery in patients with homozygous sickle cell disease: A management strategy.

    Science.gov (United States)

    Moutaouekkil, El Mehdi; Najib, Abdelmalek; Ajaja, Rida; Arji, Moha; Slaoui, Anas

    2015-01-01

    Patients with the homozygous sickle cell disease have increased perioperative mortality. Some indications like heart valve surgery, may justify an exchange blood transfusion to reduce the proportion of hemoglobin S (HbS) and complications. We report two female cases aged 20 and 27, of African origin with homozygous sickle cell anemia who underwent heart valve surgery to treat mitral valve regurgitation. This presentation describes the perioperative considerations including anesthesia and postoperative care. A partial exchange blood transfusion decreased HbS levels from respectively, 90% and 84%, 9% to 27% and 34%, and simultaneously treated the anemia. Neither sickling crisis nor acidosis occurred in any patient, and no special postoperative complication occurred. Average hospital stay was 10 days. Currently, the two patients remain alive and free of cardiac symptoms. Although the presence of sickle cell disorders is associated with increased risk of sickling and thus vaso-occlusive complications, they should not be taken as a contraindication for heart valve surgery. Nevertheless, monitoring of certain parameters such as venous, arterial oxygen content, pH, and body temperature is mandatory for a better outcome. Furthermore, preoperative exchange transfusion has a positive influence on the outcome of surgery and on the survival of patients undergoing heart valves surgery. Avoiding intraoperative hypoxia, hypothermia, and vaso-constrictive agents, minimizing HbS levels with preoperative exchange transfusion, and ensuring a stress-free environment with the judicious use of sedatives made surgery relatively safe in these cases.

  5. FastMap: fast eQTL mapping in homozygous populations.

    Science.gov (United States)

    Gatti, Daniel M; Shabalin, Andrey A; Lam, Tieu-Chong; Wright, Fred A; Rusyn, Ivan; Nobel, Andrew B

    2009-02-15

    Gene expression Quantitative Trait Locus (eQTL) mapping measures the association between transcript expression and genotype in order to find genomic locations likely to regulate transcript expression. The availability of both gene expression and high-density genotype data has improved our ability to perform eQTL mapping in inbred mouse and other homozygous populations. However, existing eQTL mapping software does not scale well when the number of transcripts and markers are on the order of 10(5) and 10(5)-10(6), respectively. We propose a new method, FastMap, for fast and efficient eQTL mapping in homozygous inbred populations with binary allele calls. FastMap exploits the discrete nature and structure of the measured single nucleotide polymorphisms (SNPs). In particular, SNPs are organized into a Hamming distance-based tree that minimizes the number of arithmetic operations required to calculate the association of a SNP by making use of the association of its parent SNP in the tree. FastMap's tree can be used to perform both single marker mapping and haplotype association mapping over an m-SNP window. These performance enhancements also permit permutation-based significance testing. The FastMap program and source code are available at the website: http://cebc.unc.edu/fastmap86.html.

  6. Mutational analysis of the PLCE1 gene in steroid resistant nephrotic syndrome.

    Science.gov (United States)

    Boyer, Olivia; Benoit, Geneviève; Gribouval, Olivier; Nevo, Fabien; Pawtowski, Audrey; Bilge, Ilmay; Bircan, Zelal; Deschênes, Georges; Guay-Woodford, Lisa M; Hall, Michelle; Macher, Marie-Alice; Soulami, Kenza; Stefanidis, Constantinos J; Weiss, Robert; Loirat, Chantal; Gubler, Marie-Claire; Antignac, Corinne

    2010-07-01

    Mutations in the PLCE1 gene encoding phospholipase C epsilon 1 (PLCepsilon1) have been recently described in patients with early onset nephrotic syndrome (NS) and diffuse mesangial sclerosis (DMS). In addition, two cases of PLCE1 mutations associated with focal segmental glomerulosclerosis (FSGS) and later NS onset have been reported. In order to better assess the spectrum of phenotypes associated with PLCE1 mutations, mutational analysis was performed in a worldwide cohort of 139 patients (95 familial cases belonging to 68 families and 44 sporadic cases) with steroid resistant NS presenting at a median age of 23.0 months (range 0-373). Homozygous or compound heterozygous mutations were identified in 33% (8/24) of DMS cases. PLCE1 mutations were found in 8% (6/78) of FSGS cases without NPHS2 mutations. Nine were novel mutations. No clear genotype-phenotype correlation was observed, with either truncating or missense mutations detected in both DMS and FSGS, and leading to a similar renal evolution. Surprisingly, three unaffected and unrelated individuals were also found to carry the homozygous mutations identified in their respective families. PLCE1 is a major gene of DMS and is mutated in a non-negligible proportion of FSGS cases without NPHS2 mutations. Although additional variants in 19 candidate genes (16 other PLC genes, BRAF,IQGAP1 and NPHS1) were not identified, it is speculated that other modifier genes or environmental factors may play a role in the renal phenotype variability observed in individuals bearing PLCE1 mutations. This observation needs to be considered in the genetic counselling offered to patients.

  7. Four Novel p.N385K, p.V36A, c.1033–1034insT and c.1417–1418delCT Mutations in the Sphingomyelin Phosphodiesterase 1 (SMPD1 Gene in Patients with Types A and B Niemann-Pick Disease (NPD

    Directory of Open Access Journals (Sweden)

    Masoumeh Dehghan Manshadi

    2015-03-01

    Full Text Available Background: Types A and B Niemann-Pick disease (NPD are autosomal-recessive lysosomal storage disorders caused by the deficient activity of acid sphingomyelinase due to mutations in the sphingomyelin phosphodiesterase 1 (SMPD1 gene. Methods: In order to determine the prevalence and distribution of SMPD1 gene mutations, the genomic DNA of 15 unrelated Iranian patients with types A and B NPD was examined using PCR, DNA sequencing and bioinformatics analysis. Results: Of 8 patients with the p.G508R mutation, 5 patients were homozygous, while the other 3 were heterozygous. One patient was heterozygous for both the p.N385K and p.G508R mutations. Another patient was heterozygous for both the p.A487V and p.G508R mutations. Two patients (one homozygous and one heterozygous showed the p.V36A mutation. One patient was homozygous for the c.1033–1034insT mutation. One patient was homozygous for the c.573delT mutation, and 1 patient was homozygous for the c.1417–1418delCT mutation. Additionally, bioinformatics analysis indicated that two new p.V36A and p.N385K mutations decreased the acid sphingomyelinase (ASM protein stability, which might be evidence to suggest the pathogenicity of these mutations. Conclusion: with detection of these new mutations, the genotypic spectrum of types A and B NPD is extended, facilitating the definition of disease-related mutations. However, more research is essential to confirm the pathogenic effect of these mutations.

  8. Case report: a novel KERA mutation associated with cornea plana and its predicted effect on protein function

    DEFF Research Database (Denmark)

    Roos, Laura; Bertelsen, Birgitte; Harris, Pernille

    2015-01-01

    Background: Cornea plana (CNA) is a hereditary congenital abnormality of the cornea characterized by reduced corneal curvature, extreme hypermetropia, corneal clouding and hazy corneal limbus. The recessive form, CNA2, is associated with homozygous or compound heterozygous mutations...... of the keratocan gene (KERA) on chromosome 12q22. To date, only nine different disease-associated KERA mutations, including four missense mutations, have been described. Case presentation: In this report, we present clinical data from a Turkish family with autosomal recessive cornea plana. In some of the affected......, and this knowledge will ease the interpretation of future findings of mutations in these areas in other families with cornea plana....

  9. Mitchell-Riley Syndrome: A Novel Mutation in RFX6 Gene

    Directory of Open Access Journals (Sweden)

    Marta Zegre Amorim

    2015-01-01

    Full Text Available A novel RFX6 homozygous missense mutation was identified in an infant with Mitchell-Riley syndrome. The most common features of Mitchell-Riley syndrome were present, including severe neonatal diabetes associated with annular pancreas, intestinal malrotation, gallbladder agenesis, cholestatic disease, chronic diarrhea, and severe intrauterine growth restriction. Perijejunal tissue similar to pancreatic tissue was found in the submucosa, a finding that has not been previously reported in this syndrome. This case associating RFX6 mutation with structural and functional pancreatic abnormalities reinforces the RFX6 gene role in pancreas development and β-cell function, adding information to the existent mutation databases.

  10. Carbonic anhydrase II deficiency: Single-base deletion in exon 7 is the predominant mutation in Caribbean Hispanic patients

    Energy Technology Data Exchange (ETDEWEB)

    Hu, P.Y.; Ernst, A.R.; Sly, W.S. (St. Louis Univ. School of Medicine, MO (United States)); Venta, P.J. (Michigan State Univ., East Lansing, MI (United States)); Skaggs, L.A.; Tashian, R.E. (Univ. of Michigan Medical School, Ann Arbor, MI (United States))

    1994-04-01

    To date, three different structural gene mutations have been identified in patients with carbonic anhydrase II deficiency (osteopetrosis with renal tubular acidosis and cerebral calcification). These include a missense mutation (H107Y) in two families, a splice junction mutation in intron 5 in one of these families, and a splice junction mutation in intron 2 for which many Arabic patients are homozygous. The authors report here a novel mutation for which carbonic anhydrase II-deficient patients from seven unrelated Hispanic families were found to be homozygous. The proband was a 2 1/2-year-old Hispanic girl of Puerto Rican ancestry who was unique clinically, in that she had no evidence of renal tubular acidosis, even though she did have osteopetrosis, developmental delay, and cerebral calcification. She proved to be homozygous for a single-base deletion in the coding region of exon 7 that produces a frameshift that changes the next 12 amino acids before leading to chain termination and that also introduces a new MaeIII restriction site. The 27-kD truncated enzyme produced when the mutant cDNA was expressed in COS cells was enzymatically inactive, present mainly in insoluble aggregates, and detectable immunologically at only 5% the level of the 29-kD normal carbonic anhydrase II expressed from the wild-type cDNA. Metabolic labeling revealed that this 27-kD mutant protein has an accelerated rate of degradation. Six subsequent Hispanic patients of Caribbean ancestry, all of whom had osteopetrosis and renal tubular acidosis but who varied widely in clinical severity, were found to be homozygous for the same mutation. These findings identify a novel mutation common to Hispanic patients from the Caribbean islands and provide a ready means for PCR-based diagnosis of the [open quotes]Hispanic mutation.[close quotes] The basis for their phenotypic variability is not yet clear. 15 refs., 5 figs., 1 tab.

  11. Mutations causing Greenberg dysplasia but not Pelger anomaly uncouple enzymatic from structural functions of a nuclear membrane protein.

    OpenAIRE

    Clayton, P; Fischer, B; Mann, A.; Mansour, S.; Rossier, E; Van der Veen, M.; C. Lang; Baasanjav, S.; Kieslich, M.; Brossuleit, K.; Gravemann, S; Schnipper, N.; Karbasyian, M.; Demuth, I.; Zwerger, M.

    2010-01-01

    The lamin B receptor (LBR) is an inner nuclear membrane protein with a structural function interacting with chromatin and lamins, and an enzymatic function as a sterol reductase. Heterozygous LBR mutations cause nuclear hyposegmentation in neutrophils (Pelger anomaly), while homozygous mutations cause prenatal death with skeletal defects and abnormal sterol metabolism (Greenberg dysplasia). It has remained unclear whether the lethality in Greenberg dysplasia is due to cholesterol defects or a...

  12. Clinical and mutational characterization of three patients with multiple sulfatase deficiency: report of a new splicing mutation.

    Science.gov (United States)

    Díaz-Font, Anna; Santamaría, Raül; Cozar, Mònica; Blanco, Mariana; Chamoles, Néstor; Coll, Maria Josep; Chabás, Amparo; Vilageliu, Lluïsa; Grinberg, Daniel

    2005-01-01

    Multiple sulfatase deficiency (MSD) is a rare autosomal recessive lysosomal storage disease characterized by impaired activity of all known sulfatases. The gene SUMF1, recently identified, encodes the enzyme responsible for post-translational modification of a cysteine residue, which is essential for the activity of sulfatases. Fewer than 30 MSD patients have been reported to date and 23 different mutations in the SUMF1 gene have been identified. Here, we present the characterization of the mutant alleles of two Spanish and one Argentinean MSD patients. While the two Spanish patients were homozygous for the previously described mutations, c.463T>C (p.S155P) and c.1033C>T (p.R345C), the Argentinean patient was homozygous for the new mutation IVS7+5 G>T. A minigene approach was used to analyze the effect of the splice site mutation identified, due to the lack of sample from the patient. This experiment showed that this change altered the normal splicing of the RNA, which strongly suggests that this is the molecular cause of the disease in this patient.

  13. Inactivation of poliovirus by chloramine-T.

    Science.gov (United States)

    Gowda, N M; Trieff, N M; Stanton, G J

    1981-01-01

    Since concern has recently been expressed about the presence of genotoxic substances due to chlorination of water and wastewater, chloramine-T (CAT) is proposed as an alternative disinfectant to chlorine. The viricidal properties of chlorine and CAT were compared. Kinetics of inactivation of poliovirus type 2 by chlorine and CAT in chlorine demand-free water were investigated by using a kinetic apparatus. Inactivation of the virus by chlorine and CAT occurred in two steps. The initial linear part of the inactivation curve followed a pseudo-first-order reaction with the virus. An obvious dose-response relationship was demonstrated with CAT. The rate of inactivation of the virus by CAT was faster in acid medium than in alkaline medium. Inactivation kinetic studies were performed at different temperatures, and the kinetic, Arrhenius, and thermodynamic parameters were evaluated. The rate of inactivation of poliovirus type 2 by chlorine was faster than that by CAT under identical conditions. A mechanism for the viral inactivation in acid conditions was proposed which led to a rate equation consistent with the experimental results. The results indicate that CAT may be an effective viricide against poliovirus type 2 in an acid medium. PMID:6271058

  14. Systematic analysis of somatic mutations impacting gene expression in 12 tumour types

    Science.gov (United States)

    Ding, Jiarui; McConechy, Melissa K.; Horlings, Hugo M.; Ha, Gavin; Chun Chan, Fong; Funnell, Tyler; Mullaly, Sarah C.; Reimand, Jüri; Bashashati, Ali; Bader, Gary D.; Huntsman, David; Aparicio, Samuel; Condon, Anne; Shah, Sohrab P.

    2015-01-01

    We present a novel hierarchical Bayes statistical model, xseq, to systematically quantify the impact of somatic mutations on expression profiles. We establish the theoretical framework and robust inference characteristics of the method using computational benchmarking. We then use xseq to analyse thousands of tumour data sets available through The Cancer Genome Atlas, to systematically quantify somatic mutations impacting expression profiles. We identify 30 novel cis-effect tumour suppressor gene candidates, enriched in loss-of-function mutations and biallelic inactivation. Analysis of trans-effects of mutations and copy number alterations with xseq identifies mutations in 150 genes impacting expression networks, with 89 novel predictions. We reveal two important novel characteristics of mutation impact on expression: (1) patients harbouring known driver mutations exhibit different downstream gene expression consequences; (2) expression patterns for some mutations are stable across tumour types. These results have critical implications for identification and interpretation of mutations with consequent impact on transcription in cancer. PMID:26436532

  15. Hb Dartmouth (HBA2: c.200T>C): An α2-Globin Gene Associated with Hb H Disease in One Homozygous Patient.

    Science.gov (United States)

    Farashi, Samaneh; Faramarzi Garous, Negin; Ashki, Mehri; Vakili, Shadi; Zeinali, Fatemah; Imanian, Hashem; Azarkeivan, Azita; Najmabadi, Hossein

    2015-01-01

    Hb H (β4) disease is caused by deletion or inactivation of three out of four α-globin genes. A high incidence of Hb H disease has been reported all over the world. There is a wide spectrum of phenotypic presentations, from clinically asymptomatic to having significant hepatosplenomegaly and requiring occasional or even regular blood transfusions, even more severe anemia, Hb Bart's (γ4) hydrops fetalis syndrome that can cause death in the affected fetuses late in gestation. We here present a case who was diagnosed with Hb H disease that represents a new genotype for this hereditary disorder. Hb Dartmouth is a variant caused by a missense mutation at codon 66 of the α2-globin gene (HBA2: c.200T>C), resulting in the substitution of leucine by proline. We here emphasize the importance of this point mutation involving Hb H disease and also the necessity for prenatal diagnosis (PND) for those who carry this point mutation in the heterozygous state.

  16. Rare mutations of the DMBT1 gene in human astrocytic gliomas

    DEFF Research Database (Denmark)

    Mueller, Wolf; Mollenhauer, Jan; Stockhammer, Florian

    2002-01-01

    The Deleted in Malignant Brain Tumors 1 gene (DMBT1) has been proposed as a tumor suppressor gene candidate in human brain tumors, based on the observation of homozygous deletions affecting the DMBT1 region or part of the gene. In order to support this hypothesis, we performed a mutational analysis...... of the entire coding region of DMBT1, employing SSCP analysis and direct DNA sequencing in a series of 79 astrocytic gliomas. Five somatic mutations were detected. Two mutations, one of which resulted in an amino acid exchange, occurred in glioblastomas. One pilocytic astrocytoma carried two missense mutations...... and another pilocytic astrocytoma contained a somatic mutation, not affecting the presumed protein. In addition, 21 of the 27 single nucleotide polymorphisms identified in this study have not been recognized previously. The data indicate, that small mutations are not a frequent finding in gliomas....

  17. Filaggrin mutations are genetic modifying factors exacerbating X-linked ichthyosis.

    Science.gov (United States)

    Liao, Haihui; Waters, Alex J; Goudie, David R; Aitken, David A; Graham, Gordon; Smith, Frances J D; Lewis-Jones, Sue; McLean, W H Irwin

    2007-12-01

    Mutations inactivating the STS gene cause X-linked ichthyosis (XLI), whereas null mutations in the FLG gene cause ichthyosis vulgaris. Two brothers presented with XLI. One had a typical fine scaling, and the other was much more severely affected. Both patients carried STS missense mutation T165I. Furthermore, the more severely affected patient also carried heterozygous FLG mutation R501X, which was absent from his mildly affected brother. These data suggest that disrupting epidermal differentiation via different pathways can increase phenotypic severity. Owing to the high population frequency of FLG mutations, filaggrin is a possible genetic modifier in other genodermatoses.

  18. Dopamine inactivation efficacy related to functional DAT1 and COMT variants influences motor response evaluation.

    Directory of Open Access Journals (Sweden)

    Stephan Bender

    Full Text Available BACKGROUND: Dopamine plays an important role in orienting, response anticipation and movement evaluation. Thus, we examined the influence of functional variants related to dopamine inactivation in the dopamine transporter (DAT1 and catechol-O-methyltransferase genes (COMT on the time-course of motor processing in a contingent negative variation (CNV task. METHODS: 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version. Early and late CNV as well as motor postimperative negative variation were assessed. Adolescents were genotyped for the COMT Val(158Met and two DAT1 polymorphisms (variable number tandem repeats in the 3'-untranslated region and in intron 8. RESULTS: The results revealed a significant interaction between COMT and DAT1, indicating that COMT exerted stronger effects on lateralized motor post-processing (centro-parietal motor postimperative negative variation in homozygous carriers of a DAT1 haplotype increasing DAT1 expression. Source analysis showed that the time interval 500-1000 ms after the motor response was specifically affected in contrast to preceding movement anticipation and programming stages, which were not altered. CONCLUSIONS: Motor slow negative waves allow the genomic imaging of dopamine inactivation effects on cortical motor post-processing during response evaluation. This is the first report to point towards epistatic effects in the motor system during response evaluation, i.e. during the post-processing of an already executed movement rather than during movement programming.

  19. Dopamine Inactivation Efficacy Related to Functional DAT1 and COMT Variants Influences Motor Response Evaluation

    Science.gov (United States)

    Bender, Stephan; Rellum, Thomas; Freitag, Christine; Resch, Franz; Rietschel, Marcella; Treutlein, Jens; Jennen-Steinmetz, Christine; Brandeis, Daniel; Banaschewski, Tobias; Laucht, Manfred

    2012-01-01

    Background Dopamine plays an important role in orienting, response anticipation and movement evaluation. Thus, we examined the influence of functional variants related to dopamine inactivation in the dopamine transporter (DAT1) and catechol-O-methyltransferase genes (COMT) on the time-course of motor processing in a contingent negative variation (CNV) task. Methods 64-channel EEG recordings were obtained from 195 healthy adolescents of a community-based sample during a continuous performance task (A-X version). Early and late CNV as well as motor postimperative negative variation were assessed. Adolescents were genotyped for the COMT Val158Met and two DAT1 polymorphisms (variable number tandem repeats in the 3′-untranslated region and in intron 8). Results The results revealed a significant interaction between COMT and DAT1, indicating that COMT exerted stronger effects on lateralized motor post-processing (centro-parietal motor postimperative negative variation) in homozygous carriers of a DAT1 haplotype increasing DAT1 expression. Source analysis showed that the time interval 500–1000 ms after the motor response was specifically affected in contrast to preceding movement anticipation and programming stages, which were not altered. Conclusions Motor slow negative waves allow the genomic imaging of dopamine inactivation effects on cortical motor post-processing during response evaluation. This is the first report to point towards epistatic effects in the motor system during response evaluation, i.e. during the post-processing of an already executed movement rather than during movement programming. PMID:22649558

  20. Genetic characterization in symptomatic female DMD carriers: lack of relationship between X-inactivation, transcriptional DMD allele balancing and phenotype

    Directory of Open Access Journals (Sweden)

    Brioschi Simona

    2012-08-01

    Full Text Available Abstract Background Although Duchenne and Becker muscular dystrophies, X-linked recessive myopathies, predominantly affect males, a clinically significant proportion of females manifesting symptoms have also been reported. They represent an heterogeneous group characterized by variable degrees of muscle weakness and/or cardiac involvement. Though preferential inactivation of the normal X chromosome has long been considered the principal mechanism behind disease manifestation in these females, supporting evidence is controversial. Methods Eighteen females showing a mosaic pattern of dystrophin expression on muscle biopsy were recruited and classified as symptomatic (7 or asymptomatic (11, based on the presence or absence of muscle weakness. The causative DMD gene mutations were identified in all cases, and the X-inactivation pattern was assessed in muscle DNA. Transcriptional analysis in muscles was performed in all females, and relative quantification of wild-type and mutated transcripts was also performed in 9 carriers. Dystrophin protein was quantified by immunoblotting in 2 females. Results The study highlighted a lack of relationship between dystrophic phenotype and X-inactivation pattern in females; skewed X-inactivation was found in 2 out of 6 symptomatic carriers and in 5 out of 11 asymptomatic carriers. All females were characterized by biallelic transcription, but no association was found between X-inactivation pattern and allele transcriptional balancing. Either a prevalence of wild-type transcript or equal proportions of wild-type and mutated RNAs was observed in both symptomatic and asymptomatic females. Moreover, very similar levels of total and wild-type transcripts were identified in the two groups of carriers. Conclusions This is the first study deeply exploring the DMD transcriptional behaviour in a cohort of female carriers. Notably, no relationship between X-inactivation pattern and transcriptional behaviour of DMD gene was

  1. Genetic characterization in symptomatic female DMD carriers: lack of relationship between X-inactivation, transcriptional DMD allele balancing and phenotype.

    Science.gov (United States)

    Brioschi, Simona; Gualandi, Francesca; Scotton, Chiara; Armaroli, Annarita; Bovolenta, Matteo; Falzarano, Maria S; Sabatelli, Patrizia; Selvatici, Rita; D'Amico, Adele; Pane, Marika; Ricci, Giulia; Siciliano, Gabriele; Tedeschi, Silvana; Pini, Antonella; Vercelli, Liliana; De Grandis, Domenico; Mercuri, Eugenio; Bertini, Enrico; Merlini, Luciano; Mongini, Tiziana; Ferlini, Alessandra

    2012-08-16

    Although Duchenne and Becker muscular dystrophies, X-linked recessive myopathies, predominantly affect males, a clinically significant proportion of females manifesting symptoms have also been reported. They represent an heterogeneous group characterized by variable degrees of muscle weakness and/or cardiac involvement. Though preferential inactivation of the normal X chromosome has long been considered the principal mechanism behind disease manifestation in these females, supporting evidence is controversial. Eighteen females showing a mosaic pattern of dystrophin expression on muscle biopsy were recruited and classified as symptomatic (7) or asymptomatic (11), based on the presence or absence of muscle weakness. The causative DMD gene mutations were identified in all cases, and the X-inactivation pattern was assessed in muscle DNA. Transcriptional analysis in muscles was performed in all females, and relative quantification of wild-type and mutated transcripts was also performed in 9 carriers. Dystrophin protein was quantified by immunoblotting in 2 females. The study highlighted a lack of relationship between dystrophic phenotype and X-inactivation pattern in females; skewed X-inactivation was found in 2 out of 6 symptomatic carriers and in 5 out of 11 asymptomatic carriers. All females were characterized by biallelic transcription, but no association was found between X-inactivation pattern and allele transcriptional balancing. Either a prevalence of wild-type transcript or equal proportions of wild-type and mutated RNAs was observed in both symptomatic and asymptomatic females. Moreover, very similar levels of total and wild-type transcripts were identified in the two groups of carriers. This is the first study deeply exploring the DMD transcriptional behaviour in a cohort of female carriers. Notably, no relationship between X-inactivation pattern and transcriptional behaviour of DMD gene was observed, suggesting that the two mechanisms are regulated

  2. Primary Ciliary Dyskinesia-Causing Mutations in Amish and Mennonite Communities

    Science.gov (United States)

    Ferkol, Thomas W.; Puffenberger, Erik G.; Lie, Hauw; Helms, Cynthia; Strauss, Kevin A.; Bowcock, Anne; Carson, John L.; Hazucha, Milan; Morton, D. Holmes; Patel, Anand C.; Leigh, Margaret W.; Knowles, Michael R.; Zariwala, Maimoona A.

    2013-01-01

    Objective To determine whether individuals with primary ciliary dyskinesia (PCD) from unrelated Amish and Mennonite families harbor a single and unique founder mutation. Study design Subjects from Amish and Mennonite communities in several states were enrolled in the study. All subjects were clinically characterized, and nasal nitric oxide levels were measured. Nasal epithelial scrapings were collected from several subjects for ciliary ultrastructural analyses. DNA was isolated from patients with PCD and their unaffected first- and second-degree relatives. Genome-wide homozygosity mapping, linkage analyses, targeted mutation analyses, and exome sequencing were performed. Results All subjects from Old-Order Amish communities from Pennsylvania were homozygous for a nonsense mutant DNAH5 allele, c.4348C>T (p.Q1450X). Two affected siblings from an unrelated Mennonite family in Arkansas were homozygous for the same nonsense DNAH5 mutation. Children with PCD from an Amish family from Wisconsin had biallelic DNAH5 mutations, c.4348C>T (p.Q1450X) and c.10815delT (p.P3606HfsX23), and mutations in other genes associated with PCD were also identified in this community. Conclusion The Amish and Mennonite subjects from geographically dispersed and socially isolated communities had the same founder DNAH5 mutation, owing to the common heritage of these populations. However, disease-causing mutations in other PCD-associated genes were also found in affected individuals in these communities, illustrating the genetic heterogeneity in this consanguineous population. PMID:23477994

  3. Primary ciliary dyskinesia-causing mutations in Amish and Mennonite communities.

    Science.gov (United States)

    Ferkol, Thomas W; Puffenberger, Erik G; Lie, Hauw; Helms, Cynthia; Strauss, Kevin A; Bowcock, Anne; Carson, John L; Hazucha, Milan; Morton, D Holmes; Patel, Anand C; Leigh, Margaret W; Knowles, Michael R; Zariwala, Maimoona A

    2013-08-01

    To determine whether individuals with primary ciliary dyskinesia (PCD) from unrelated Amish and Mennonite families harbor a single and unique founder mutation. Subjects from Amish and Mennonite communities in several states were enrolled in the study. All subjects were clinically characterized, and nasal nitric oxide levels were measured. Nasal epithelial scrapings were collected from several subjects for ciliary ultrastructural analyses. DNA was isolated from patients with PCD and their unaffected first- and second-degree relatives. Genome-wide homozygosity mapping, linkage analyses, targeted mutation analyses, and exome sequencing were performed. All subjects from Old-Order Amish communities from Pennsylvania were homozygous for a nonsense mutant DNAH5 allele, c.4348C>T (p.Q1450X). Two affected siblings from an unrelated Mennonite family in Arkansas were homozygous for the same nonsense DNAH5 mutation. Children with PCD from an Amish family from Wisconsin had biallelic DNAH5 mutations, c.4348C>T (p.Q1450X) and c.10815delT (p.P3606HfsX23), and mutations in other genes associated with PCD were also identified in this community. The Amish and Mennonite subjects from geographically dispersed and socially isolated communities had the same founder DNAH5 mutation, owing to the common heritage of these populations. However, disease-causing mutations in other PCD-associated genes were also found in affected individuals in these communities, illustrating the genetic heterogeneity in this consanguineous population. Copyright © 2013 Mosby, Inc. All rights reserved.

  4. Silence of the fathers: early X inactivation.

    Science.gov (United States)

    Cheng, Mimi K; Disteche, Christine M

    2004-08-01

    X chromosome inactivation is the mammalian answer to the dilemma of dosage compensation between males and females. The study of this fascinating form of chromosome-wide gene regulation has yielded surprising insights into early development and cellular memory. In the past few months, three papers reported unexpected findings about the paternal X chromosome (X(p)). All three studies agree that the X(p) is imprinted to become inactive earlier than ever suspected during embryonic development. Although apparently incomplete, this early form of inactivation insures dosage compensation throughout development. Silencing of the X(p) persists in cells of extraembryonic tissues, but it is erased and followed by random X inactivation in cells of the embryo proper. These findings challenge several aspects of the current view of X inactivation during early development and may have profound impact on studies of pluripotency and epigenetics.

  5. Lidocaine reduces the transition to slow inactivation in Nav1.7 voltage-gated sodium channels

    Science.gov (United States)

    Sheets, Patrick L; Jarecki, Brian W; Cummins, Theodore R

    2011-01-01

    BACKGROUND AND PURPOSE The primary use of local anaesthetics is to prevent or relieve pain by reversibly preventing action potential propagation through the inhibition of voltage-gated sodium channels. The tetrodotoxin-sensitive voltage-gated sodium channel subtype Nav1.7, abundantly expressed in pain-sensing neurons, plays a crucial role in perception and transmission of painful stimuli and in inherited chronic pain syndromes. Understanding the interaction of lidocaine with Nav1.7 channels could provide valuable insight into the drug's action in alleviating pain in distinct patient populations. The aim of this study was to determine how lidocaine interacts with multiple inactivated conformations of Nav1.7 channels. EXPERIMENTAL APPROACH We investigated the interactions of lidocaine with wild-type Nav1.7 channels and a paroxysmal extreme pain disorder mutation (I1461T) that destabilizes fast inactivation. Whole cell patch clamp recordings were used to examine the activity of channels expressed in human embryonic kidney 293 cells. KEY RESULTS Depolarizing pulses that increased slow inactivation of Nav1.7 channels also reduced lidocaine inhibition. Lidocaine enhanced recovery of Nav1.7 channels from prolonged depolarizing pulses by decreasing slow inactivation. A paroxysmal extreme pain disorder mutation that destabilizes fast inactivation of Nav1.7 channels decreased lidocaine inhibition. CONCLUSIONS AND IMPLICATIONS Lidocaine decreased the transition of Nav1.7 channels to the slow inactivated state. The fast inactivation gate (domain III–IV linker) is important for potentiating the interaction of lidocaine with the Nav1.7 channel. PMID:21232038

  6. Haploid technology allows for the efficient and rapid generation of homozygous antibody-accumulating transgenic tobacco plants.

    Science.gov (United States)

    Floss, Doreen M; Kumlehn, Jochen; Conrad, Udo; Saalbach, Isolde

    2009-09-01

    The large-scale production of plant-derived recombinant proteins requires the breeding of lines homozygous for the transgene(s). These can be selected by progeny testing over multiple sexual generations, but a more efficient means is to fix homozygosity in a single generation using doubled haploid technology. In this study, transgenic tobacco plants, hemizygous for both of the independently inherited genes encoding the light and heavy chains of the anti-human immunodeficiency virus monoclonal antibody 2F5, were used to establish embryogenic pollen cultures. The improved protocol employed in this study guaranteed a very high regeneration efficiency, with more than 50% of the regenerants being spontaneously doubled haploids. Hence, there was no requirement to chemically induce chromosome doubling to recover sufficient entirely homozygous recombinants. As expected, approximately 25% of the regenerants were homozygous for both transgenes. Thus, the employment of haploid technology allowed for the efficient and rapid generation of true-breeding tobacco lines accumulating functional immunoglobulins.

  7. Novel EXOSC3 mutation causes complicated hereditary spastic paraplegia.

    Science.gov (United States)

    Halevy, Ayelet; Lerer, Israela; Cohen, Rony; Kornreich, Liora; Shuper, Avinoam; Gamliel, Moria; Zimerman, Bat-El; Korabi, Isam; Meiner, Vardiella; Straussberg, Rachel; Lossos, Alexander

    2014-11-01

    We describe two pairs of siblings from a consanguineous family manifesting autosomal recessive hereditary spastic paraplegia caused by a novel mutation in the EXOSC3 gene, previously reported in pontocerebellar hypoplasia type 1. Clinical findings included delayed motor milestones, early-onset spastic paraplegia, variable cognitive disability, and cerebellar signs. Cerebral imaging demonstrated enlarged cisterna magna and mild hypoplasia and atrophy of the lower vermis with a normal pons. Genetic analysis using homozygosity mapping followed by whole exome sequencing identified homozygous c.571G>T; p.G191C mutation in the EXOSC3 gene. We suggest that EXOSC3 mutations may present not only as pontocerebellar hypoplasia type 1, but also as a complicated form of hereditary spastic paraplegia without pontine hypoplasia or atrophy.

  8. Limb defects in homozygous {alpha}-thalassemia: Report of three cases

    Energy Technology Data Exchange (ETDEWEB)

    Chitayat, D.; Thomas, M.; Silver, M.M. [Univ. of Toronto, Ontario (Canada)] [and others

    1997-01-20

    Homozygosity for the South-Asian {alpha}-thalassemia (--{sup SEA}/) deletion is a serious hematological condition that results, in most cases, in intrauterine or postnatal death due to anemia and severe hypoxia of prenatal onset. A relationship between congenital abnormalities and intrauterine hypoxia has been postulated. However, since homozygosity for the (--{sup SEA}/) deletion is most common in underdeveloped countries where detailed autopsies are lacking, the incidence of congenital abnormalities among these babies has not been well delineated. We report on three newborn infants, homozygous for the (--{sup SEA}/) deletion, who were born with limb defects. We postulate that this combination is the result of prenatal hypoxia which may affect other fetal body organs. This should be taken into consideration when prenatal treatment of affected fetuses, with intrauterine blood transfusion, is suggested. 47 refs., 3 figs.

  9. Clinical management of the homozygous α-thalassemia with unusual mandibular manifestation of hematopoiesis.

    Science.gov (United States)

    Ruiz-Roca, J A; Oñate-Sánchez, R E; Urrutia-Rodríguez, I; Martínez-Izquierdo, A; Mengual-Pujante, D; Rodríguez-Lozano, F J

    2017-02-01

    Alpha (α)-thalassemias are the most common genetic disorder of hemoglobin (Hb) synthesis, affecting up to 5% of the world's population. These congenital hemolytic anemias induce extramedullary hematopoiesis, including the liver, spleen, sinuses, and the diploic spaces of the skull. Oral health problems in patients with thalassemias are mostly related to a varied degree of facial deformities, malocclusions, and/or dental arch dimensions. We present a case with a 49-year-old man, diagnosed with homozygous α thalassemia that came to the Faculty of Dentistry at the University of Murcia for a dental treatment. It was observed that the patient had an unusual mandibular manifestation of hematopoiesis. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  10. Network-assisted target identification for haploinsufficiency and homozygous profiling screens

    Science.gov (United States)

    Wang, Sheng

    2017-01-01

    Chemical genomic screens have recently emerged as a systematic approach to drug discovery on a genome-wide scale. Drug target identification and elucidation of the mechanism of action (MoA) of hits from these noisy high-throughput screens remain difficult. Here, we present GIT (Genetic Interaction Network-Assisted Target Identification), a network analysis method for drug target identification in haploinsufficiency profiling (HIP) and homozygous profiling (HOP) screens. With the drug-induced phenotypic fitness defect of the deletion of a gene, GIT also incorporates the fitness defects of the gene’s neighbors in the genetic interaction network. On three genome-scale yeast chemical genomic screens, GIT substantially outperforms previous scoring methods on target identification on HIP and HOP assays, respectively. Finally, we showed that by combining HIP and HOP assays, GIT further boosts target identification and reveals potential drug’s mechanism of action. PMID:28574983

  11. Microbial Inactivation by Ultrasound Assisted Supercritical Fluids

    Science.gov (United States)

    Benedito, Jose; Ortuño, Carmen; Castillo-Zamudio, Rosa Isela; Mulet, Antonio

    A method combining supercritical carbon dioxide (SC-CO2) and high power ultrasound (HPU) has been developed and tested for microbial/enzyme inactivation purposes, at different process conditions for both liquid and solid matrices. In culture media, using only SC-CO2, the inactivation rate of E. coli and S. cerevisiae increased with pressure and temperature; and the total inactivation (7-8 log-cycles) was attained after 25 and 140 min of SC-CO2 (350 bar, 36 °C) treatment, respectively. Using SC-CO2+HPU, the time for the total inactivation of both microorganisms was reduced to only 1-2 min, at any condition selected. The SC-CO2+HPU inactivation of both microorganisms was slower in juices (avg. 4.9 min) than in culture media (avg. 1.5 min). In solid samples (chicken, turkey ham and dry-cured pork cured ham) treated with SC-CO2 and SC-CO2+HPU, the inactivation rate of E. coli increased with temperature. The application of HPU to the SC-CO2 treatments accelerated the inactivation rate of E. coli and that effect was more pronounced in treatments with isotonic solution surrounding the solid food samples. The application of HPU enhanced the SC-CO2 inactivation mechanisms of microorganisms, generating a vigorous agitation that facilitated the CO2 solubilization and the mass transfer process. The cavitation generated by HPU could damage the cell walls accelerating the extraction of vital constituents and the microbial death. Thus, using the combined technique, reasonable industrial processing times and mild process conditions could be used which could result into a cost reduction and lead to the minimization in the food nutritional and organoleptic changes.

  12. Prevalence and correlates of metabolic acidosis among patients with homozygous sickle cell disease.

    Science.gov (United States)

    Maurel, Stéphane; Stankovic Stojanovic, Katia; Avellino, Virginie; Girshovich, Alexey; Letavernier, Emmanuel; Grateau, Gilles; Baud, Laurent; Girot, Robert; Lionnet, Francois; Haymann, Jean-Philippe

    2014-04-01

    Very few studies report acid base disorders in homozygous patients with sickle cell anemia (SCA) and describe incomplete renal acidosis rather than true metabolic acidosis, the prevalence of which is unknown and presumably low. This study aimed to assess the prevalence of metabolic acidosis and to identify its risk factors and mechanisms. This study retrospectively analyzed 411 homozygous patients with SCA with a GFR ≥ 60 ml/min per 1.73 m(2), referred in a single center between 2007 and 2012. Acidosis and nonacidosis groups were compared for clinical and biologic data including SCA complications and hemolytic parameters. A subgroup of 65 patients with SCA, referred for a measured GFR evaluation in the setting of sickle cell-associated nephropathy, was further analyzed in order to better characterize metabolic acidosis. Metabolic acidosis was encountered in 42% of patients with SCA, with a higher prevalence in women (52% versus 27% in men; Pacidosis and nonacidosis groups (P=0.02 and P=0.03 in men and women, respectively), suggesting higher hemolytic activity in the former group. To note, fasting urine osmolality was low in the whole study population and was significantly lower in men with SCA in the acidosis group (392 versus 427 mOsm/kg; P=0.01). SCA subgroup analysis confirmed metabolic acidosis with a normal anion gap in 14 patients, characterized by a lower urinary pH (Pmetabolic acidosis in patients with SCA is underestimated and related to impaired ammonium availability possibly due to an altered corticopapillary gradient. Future studies should evaluate whether chronic metabolic acidosis correction may be beneficial in this population, especially in bone remodeling.

  13. The Importance of Homozygous Polymorphisms of Methylenetetrahydrofolate Reductase Gene in Romanian Patients with Idiopathic Venous Thromboembolism

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    Cristina Hotoleanu

    2013-06-01

    Full Text Available Background: Methylenetetrahydrofolate reductase (MTHFR polymorphisms have recently raised the interest as a possible thrombophilic factors. Aims: We aimed to assess the frequency of the methylenetetrahydrofolate reductase (MTHFR C677T and A1298C polymorphisms in idiopathic venous thromboembolism (VTE in a Romanian population and the associated risk of VTE. Study Design: We performed a case-control transversal study including 90 patients diagnosed with VTE and 75 sex- and age-matched controls. Methods: MTHFR C677T and A1298C polymorphisms were detected using PCR-RFLP method. Results: The homozygous MTHFR 677TT genotype, present in 18.8% of patients with VTE versus 6.6% of controls, was significantly associated with VTE (p= 0.021, OR= 3.26, 95%CI (1.141-9.313. The heterozygous MTHFR A1298C genotype, presenting the highest prevalence in the VTE group (34.4% as well as in controls (37.3%, was not associated with VTE (p=0.7. No associations were found for heterozygous MTHFR C677T (with a frequency of 32.2% in VTE and 37.3% in controls, p=0.492, respective homozygous MTHFR A1298C genotype (with a frequency of 1.1% in VTE and 2.6% in controls, p=0.456. Conclusion: Among MTHFR polymorphisms, only homozygosity for MTHFR 677TT may be considered a risk factor for VTE; the MTHFR A1298C polymorphism is not significantly associated with an increased risk of VTE.

  14. ChopSticks: High-resolution analysis of homozygous deletions by exploiting concordant read pairs

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    Yasuda Tomohiro

    2012-10-01

    Full Text Available Abstract Background Structural variations (SVs in genomes are commonly observed even in healthy individuals and play key roles in biological functions. To understand their functional impact or to infer molecular mechanisms of SVs, they have to be characterized with the maximum resolution. However, high-resolution analysis is a difficult task because it requires investigation of the complex structures involved in an enormous number of alignments of next-generation sequencing (NGS reads and genome sequences that contain errors. Results We propose a new method called ChopSticks that improves the resolution of SV detection for homozygous deletions even when the depth of coverage is low. Conventional methods based on read pairs use only discordant pairs to localize the positions of deletions, where a discordant pair is a read pair whose alignment has an aberrant strand or distance. In contrast, our method exploits concordant reads as well. We theoretically proved that when the depth of coverage approaches zero or infinity, the expected resolution of our method is asymptotically equal to that of methods based only on discordant pairs under double coverage. To confirm the effectiveness of ChopSticks, we conducted computational experiments against both simulated NGS reads and real NGS sequences. The resolution of deletion calls by other methods was significantly improved, thus demonstrating the usefulness of ChopSticks. Conclusions ChopSticks can generate high-resolution deletion calls of homozygous deletions using information independent of other methods, and it is therefore useful to examine the functional impact of SVs or to infer SV generation mechanisms.

  15. Prevalence and Correlates of Metabolic Acidosis among Patients with Homozygous Sickle Cell Disease

    Science.gov (United States)

    Maurel, Stéphane; Stankovic Stojanovic, Katia; Avellino, Virginie; Girshovich, Alexey; Letavernier, Emmanuel; Grateau, Gilles; Baud, Laurent; Girot, Robert; Lionnet, Francois

    2014-01-01

    Background and objectives Very few studies report acid base disorders in homozygous patients with sickle cell anemia (SCA) and describe incomplete renal acidosis rather than true metabolic acidosis, the prevalence of which is unknown and presumably low. This study aimed to assess the prevalence of metabolic acidosis and to identify its risk factors and mechanisms. Design, setting, participants, & measurements This study retrospectively analyzed 411 homozygous patients with SCA with a GFR≥60 ml/min per 1.73 m2, referred in a single center between 2007 and 2012. Acidosis and nonacidosis groups were compared for clinical and biologic data including SCA complications and hemolytic parameters. A subgroup of 65 patients with SCA, referred for a measured GFR evaluation in the setting of sickle cell–associated nephropathy, was further analyzed in order to better characterize metabolic acidosis. Results Metabolic acidosis was encountered in 42% of patients with SCA, with a higher prevalence in women (52% versus 27% in men; Pacidosis and nonacidosis groups (P=0.02 and P=0.03 in men and women, respectively), suggesting higher hemolytic activity in the former group. To note, fasting urine osmolality was low in the whole study population and was significantly lower in men with SCA in the acidosis group (392 versus 427 mOsm/kg; P=0.01). SCA subgroup analysis confirmed metabolic acidosis with a normal anion gap in 14 patients, characterized by a lower urinary pH (Pacidosis in patients with SCA is underestimated and related to impaired ammonium availability possibly due to an altered corticopapillary gradient. Future studies should evaluate whether chronic metabolic acidosis correction may be beneficial in this population, especially in bone remodeling. PMID:24458070

  16. Photodynamic-induced inactivation of Propionibacterium acnes

    Science.gov (United States)

    Koenig, Karsten; Teschke, M.; Eick, Stephen G.; Pfister, W.; Meyer, Herbert; Halbhuber, Karl-Juergen

    1998-05-01

    We report on photodynamically induced inactivation of the skin bacterium Propionibacterium acnes (P. acnes) using endogenous as well as exogenous photosensitizers and red light sources. P. acnes is involved in the pathogenesis of the skin disease acne vulgaris. The skin bacterium is able to synthesize the metal-free fluorescent porphyrins protoporphyrin IX (PP) and coproporphyrin (CP) as shown by in situ spectrally-resolved detection of natural autofluorescence of human skin and bacteria colonies. These naturally occurring intracellular porphyrins act as efficient endogenous photosensitizers. Inactivation of P. acnes suspensions was achieved by irradiation with He-Ne laser light in the red spectral region (632.8 nm). We monitored the photodynamically-induced death of single bacteria using a fluorescent viability kit in combination with confocal laser scanning microscopy. In addition, the photo-induced inactivation was calculated by CFU (colony forming units) determination. We found 633 nm-induced inactivation (60 mW, 0.12 cm2 exposure area, 1 hour irradiation) of 72% in the case of non-incubated bacteria based on the destructive effect of singlet oxygen produced by red light excited endogenous porphyrins and subsequent energy transfer to molecular oxygen. In order to achieve a nearly complete inactivation within one exposure procedure, the exogenous photosensitizer Methylene Blue (Mb) was added. Far red exposure of Mb-labeled bacteria using a krypton ion laser at 647 nm and 676 nm resulted in 99% inactivation.

  17. The deafness-causing mutation c.508_511dup in the GJB2 gene and a literature review.

    Science.gov (United States)

    Zhu, Yi-Ming; Li, Yong; Wang, Yan-Li; Bian, Pan-Pan; Xu, Bai-Cheng; Liu, Xiao-Wen; Chen, Xing-Jian; Liu, Feng; Guo, Yu-Fen; Wang, Qiu-Ju

    2015-09-01

    The mutation c.508_511dup in GJB2 gene has been incorrectly named as other mutations. It is essential to standardize mutation nomenclature to describe complex mutations. This paper aimed to verify a series of patients with the frame-shift mutation c.508_511dup in the GJB2 gene and review the literature on related mutations. All the included patients with non-syndromic hearing loss (NSHL) carried the 504insAACG or c.508_511dup mutation of the GJB2 gene in the present study. Their parents were encouraged to participate. After written informed consent and clinic data had been obtained, genomic DNA was extracted from venous blood of participants. The target fragments were amplified by polymerase chain reaction (PCR) and subjected to bidirectional sequencing to identify sequence variations. A total of 14 patients with prelingual NSHL and 6 normal parents were recruited. Genotyping revealed that one mutation, c.508_511dup (not 504insAACG), was homozygous in 1 patient, heterozygous in 2 patients and 3 parents, and compound heterozygous in 11 patients. Twelve patients had hearing loss caused by c.508_511dup in a homozygous or compound heterozygous form, and further study showed that it was wrongly named as 504insAACG. Additionally, according to the standard nomenclature, the previously reported mutations with distinct names from the literature review may be replaced by c.508_511dup.

  18. Hemochromatosis (HFE gene mutations in Brazilian chronic hemodialysis patients

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    F.V. Perícole

    2005-09-01

    Full Text Available Patients with chronic renal insufficiency (CRI have reduced hemoglobin levels, mostly as a result of decreased kidney production of erythropoietin, but the relation between renal insufficiency and the magnitude of hemoglobin reduction has not been well defined. Hereditary hemochromatosis is an inherited disorder of iron metabolism. The importance of the association of hemochromatosis with treatment for anemia among patients with CRI has not been well described. We analyzed the frequency of the C282Y and H63D mutations in the HFE gene in 201 Brazilian individuals with CRI undergoing hemodialysis. The analysis of the effects of HFE mutations on iron metabolism and anemia with biochemical parameters was possible in 118 patients of this study (hemoglobin, hematocrit, ferritin levels, transferrin saturation, and serum iron. A C282Y heterozygous mutation was found in 7/201 (3.4% and H63D homozygous and heterozygous mutation were found in 2/201 (1.0% and 46/201 (22.9%, respectively. The allelic frequencies of the HFE mutations (0.017 for C282Y mutation and 0.124 for H63D mutation did not differ between patients with CRI and healthy controls. Regarding the biochemical parameters, no differences were observed between HFE heterozygous and mutation-negative patients, although ferritin levels were not higher among patients with the H63D mutation (P = 0.08. From what we observed in our study, C282Y/H63D HFE gene mutations are not related to degrees of anemia or iron stores in CRI patients receiving intravenous iron supplementation (P > 0.10. Nevertheless, the present data suggest that the H63D mutation may have an important function as a modulating factor of iron overload in these patients.

  19. Beta-thalassaemia mutations in northern India (Delhi).

    Science.gov (United States)

    Madan, N; Sharma, S; Rusia, U; Sen, S; Sood, S K

    1998-03-01

    The present study was undertaken to define beta-thalassaemia mutations prevalent in northern India (Delhi). Forty six children of beta-thalassaemia major and their families were investigated. DNA was extracted from leucocytes and screened for mutations prevalent in the Indian population. These mutations included 619bp deletion, IVS 1-1 (G-T), IVS 1-5 (G-C), frameshift mutations FS 8/9 (+G), FS 41/42 (-CTTT), Codon 16(-C), Codon 15 (G-A), codon 30 (G-C), IVS 1-110 (G-A) and -88 (C-T). 619 bp deletion mutation was detected directly by amplification of DNA by PCR followed by agarose gel electrophoresis. Other mutations were studied by DNA amplification and dot blot hybridization using synthetic normal and mutant oligonucleotide probes labelled at 5' end with gamma-32 P-ATP. Five mutations accounted for all the chromosomes in 46 patients. 619 bp deletion mutation was found to be the commonest mutation (34.8%) followed by IVS 1-5 (G-C) in 22.8 per cent, IVS 1-1 (G-T) in 19.6 per cent, FS 8/9 (+G) in 13 per cent and FS 41/42 (-CTTT) in 9.8 per cent. Nineteen (41.3%) patients were homozygous and 27 (58.7%) double heterozygous for different beta-thalassaemia mutations. This observation of limited number of mutations is significant and will be useful in planning strategies for prenatal diagnosis of beta-thalassaemia in northern India.

  20. Retrospective analysis of cohort database: Phenotypic variability in a large dataset of patients confirmed to have homozygous familial hypercholesterolemia

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    Frederick J. Raal

    2016-06-01

    Full Text Available These data describe the phenotypic variability in a large cohort of patients confirmed to have homozygous familial hypercholesterolemia. Herein, we describe the observed relationship of treated low-density lipoprotein cholesterol with age. We also overlay the low-density lipoprotein receptor gene (LDLR functional status with these phenotypic data. A full description of these data is available in our recent study published in Atherosclerosis, “Phenotype Diversity Among Patients With Homozygous Familial Hypercholesterolemia: A Cohort Study” (Raal et al., 2016 [1].

  1. SPOP mutation leads to genomic instability in prostate cancer

    Science.gov (United States)

    Boysen, Gunther; Barbieri, Christopher E; Prandi, Davide; Blattner, Mirjam; Chae, Sung-Suk; Dahija, Arun; Nataraj, Srilakshmi; Huang, Dennis; Marotz, Clarisse; Xu, Limei; Huang, Julie; Lecca, Paola; Chhangawala, Sagar; Liu, Deli; Zhou, Pengbo; Sboner, Andrea; de Bono, Johann S

    2015-01-01

    Genomic instability is a fundamental feature of human cancer often resulting from impaired genome maintenance. In prostate cancer, structural genomic rearrangements are a common mechanism driving tumorigenesis. However, somatic alterations predisposing to chromosomal rearrangements in prostate cancer remain largely undefined. Here, we show that SPOP, the most commonly mutated gene in primary prostate cancer modulates DNA double strand break (DSB) repair, and that SPOP mutation is associated with genomic instability. In vivo, SPOP mutation results in a transcriptional response consistent with BRCA1 inactivation resulting in impaired homology-directed repair (HDR) of DSB. Furthermore, we found that SPOP mutation sensitizes to DNA damaging therapeutic agents such as PARP inhibitors. These results implicate SPOP as a novel participant in DSB repair, suggest that SPOP mutation drives prostate tumorigenesis in part through genomic instability, and indicate that mutant SPOP may increase response to DNA-damaging therapeutics. DOI: http://dx.doi.org/10.7554/eLife.09207.001 PMID:26374986

  2. SDH mutations establish a hypermethylator phenotype in paraganglioma.

    Science.gov (United States)

    Letouzé, Eric; Martinelli, Cosimo; Loriot, Céline; Burnichon, Nelly; Abermil, Nasséra; Ottolenghi, Chris; Janin, Maxime; Menara, Mélanie; Nguyen, An Thach; Benit, Paule; Buffet, Alexandre; Marcaillou, Charles; Bertherat, Jérôme; Amar, Laurence; Rustin, Pierre; De Reyniès, Aurélien; Gimenez-Roqueplo, Anne-Paule; Favier, Judith

    2013-06-10

    Paragangliomas are neuroendocrine tumors frequently associated with mutations in RET, NF1, VHL, and succinate dehydrogenase (SDHx) genes. Methylome analysis of a large paraganglioma cohort identified three stable clusters, associated with distinct clinical features and mutational status. SDHx-related tumors displayed a hypermethylator phenotype, associated with downregulation of key genes involved in neuroendocrine differentiation. Succinate accumulation in SDH-deficient mouse chromaffin cells led to DNA hypermethylation by inhibition of 2-OG-dependent histone and DNA demethylases and established a migratory phenotype reversed by decitabine treatment. Epigenetic silencing was particularly severe in SDHB-mutated tumors, potentially explaining their malignancy. Finally, inactivating FH mutations were identified in the only hypermethylated tumor without SDHx mutations. These findings emphasize the interplay between the Krebs cycle, epigenomic changes, and cancer. Copyright © 2013 Elsevier Inc. All rights reserved.

  3. Prevalence of deleterious ATM germline mutations in gastric cancer patients.

    Science.gov (United States)

    Huang, Dong-Sheng; Tao, Hou-Quan; He, Xu-Jun; Long, Ming; Yu, Sheng; Xia, Ying-Jie; Wei, Zhang; Xiong, Zikai; Jones, Sian; He, Yiping; Yan, Hai; Wang, Xiaoyue

    2015-12-01

    Besides CDH1, few hereditary gastric cancer predisposition genes have been previously reported. In this study, we discovered two germline ATM mutations (p.Y1203fs and p.N1223S) in a Chinese family with a history of gastric cancer by screening 83 cancer susceptibility genes. Using a published exome sequencing dataset, we found deleterious germline mutations of ATM in 2.7% of 335 gastric cancer patients of different ethnic origins. The frequency of deleterious ATM mutations in gastric cancer patients is significantly higher than that in general population (p=0.0000435), suggesting an association of ATM mutations with gastric cancer predisposition. We also observed biallelic inactivation of ATM in tumors of two gastric cancer patients. Further evaluation of ATM mutations in hereditary gastric cancer will facilitate genetic testing and risk assessment.

  4. HFE gene mutations and iron status of Brazilian blood donors

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    P.C.J.L. Santos

    2010-01-01

    Full Text Available Mutations of the HFE and TFR2 genes have been associated with iron overload. HFE and TFR2 mutations were assessed in blood donors, and the relationship with iron status was evaluated. Subjects (N = 542 were recruited at the Hemocentro da Santa Casa de São Paulo, São Paulo, Brazil. Iron status was not influenced by HFE mutations in women and was independent of blood donation frequency. In contrast, men carrying the HFE 282CY genotype had lower total iron-binding capacity (TIBC than HFE 282CC genotype carriers. Men who donated blood for the first time and were carriers of the HFE 282CY genotype had higher transferrin saturation values and lower TIBC concentrations than those with the homozygous wild genotype for the HFE C282Y mutation. Moreover, in this group of blood donors, carriers of HFE 63DD plus 63HD genotypes had higher serum ferritin values than those with the homozygous wild genotype for HFE H63D mutation. Multiple linear regression analysis showed that HFE 282CY leads to a 17.21% increase (P = 0.018 and a 83.65% decrease (P = 0.007 in transferrin saturation and TIBC, respectively. In addition, serum ferritin is influenced by age (3.91%, P = 0.001 and the HFE 63HD plus DD genotype (55.84%, P = 0.021. In conclusion, the HFE 282Y and 65C alleles were rare, while the HFE 63D allele was frequent in Brazilian blood donors. The HFE C282Y and H63D mutations were associated with alterations in iron status in blood donors in a gender-dependent manner.

  5. Prevalence of GJB2 mutations in the Silk Road region of China and a report of three novel variants.

    Science.gov (United States)

    Du, Wan; Zhu, Yi Ming; Guo, Yu Fen; Wang, Qiu Ju; Liu, Xiao Wen

    2014-04-01

    The c.235delC of GJB2 gene is the hotspot mutation of the hearing loss population in the Silk Road region of China. It is high time that some active interventions (such as hearing aids or cochlear implant) are provided to improve their language ability and quality of life. The first gene to be identified for humans with nonsyndromic hearing loss was GJB2 gene. We investigated the prevalence of GJB2 mutations in the Silk Road region of China to study the mutation spectrum in this area. Bidirectional sequencing was carried out for all PCR products of samples. The statistical analysis was carried out using SAS 9.0.1 software. Pathogenic mutations were identified in 243 of 2398 patients, including 168 homozygous mutations and 75 compound heterozygous mutations. Three variants (c.225G>T, c.521G>A, and c.557C>T) are novel mutations.

  6. Role of the factor V Leiden mutation in septic peritonitis assessed in factor V Leiden transgenic mice

    NARCIS (Netherlands)

    Brüggemann, Lois W.; Schoenmakers, Saskia H. H. F.; Groot, Angelique P.; Reitsma, Pieter H.; Spek, C. Arnold

    2006-01-01

    OBJECTIVE: The factor V Leiden (FVL) mutation (Arg506Glu) results in the production of an FV protein that when activated is relatively resistant to inactivation by activated protein C and thereby leads to predisposition to thrombosis. The rather high prevalence of the FVL mutation in the general

  7. Familial isolated primary pigmented nodular adrenocortical disease associated with a novel low penetrance PRKAR1A gene splice site mutation

    DEFF Research Database (Denmark)

    Storr, Helen L; Metherell, Louise A; Dias, Renuka

    2010-01-01

    Primary pigmented nodular adrenocortical disease (PPNAD) is associated with inactivating germline protein kinase A regulatory subunit type 1-alpha (PRKAR1A) mutations and loss of heterozygosity at the 17q22-24 locus in approximately 50% patients. PRKAR1A mutations are observed in both isolated PP...

  8. Clinical and genetic characterization of manifesting carriers of DMD mutations.

    Science.gov (United States)

    Soltanzadeh, Payam; Friez, Michael J; Dunn, Diane; von Niederhausern, Andrew; Gurvich, Olga L; Swoboda, Kathryn J; Sampson, Jacinda B; Pestronk, Alan; Connolly, Anne M; Florence, Julaine M; Finkel, Richard S; Bönnemann, Carsten G; Medne, Livija; Mendell, Jerry R; Mathews, Katherine D; Wong, Brenda L; Sussman, Michael D; Zonana, Jonathan; Kovak, Karen; Gospe, Sidney M; Gappmaier, Eduard; Taylor, Laura E; Howard, Michael T; Weiss, Robert B; Flanigan, Kevin M

    2010-08-01

    Manifesting carriers of DMD gene mutations may present diagnostic challenges, particularly in the absence of a family history of dystrophinopathy. We review the clinical and genetic features in 15 manifesting carriers identified among 860 subjects within the United Dystrophinopathy Project, a large clinical dystrophinopathy cohort whose members undergo comprehensive DMD mutation analysis. We defined manifesting carriers as females with significant weakness, excluding those with only myalgias/cramps. DNA extracted from peripheral blood was used to study X-chromosome inactivation patterns. Among these manifesting carriers, age at symptom onset ranged from 2 to 47 years. Seven had no family history and eight had male relatives with Duchenne muscular dystrophy (DMD). Clinical severity among the manifesting carriers varied from a DMD-like progression to a very mild Becker muscular dystrophy-like phenotype. Eight had exonic deletions or duplications and six had point mutations. One patient had two mutations (an exonic deletion and a splice site mutation), consistent with a heterozygous compound state. The X-chromosome inactivation pattern was skewed toward non-random in four out of seven informative deletions or duplications but was random in all cases with nonsense mutations. We present the results of DMD mutation analysis in this manifesting carrier cohort, including the first example of a presumably compound heterozygous DMD mutation. Our results demonstrate that improved molecular diagnostic methods facilitate the identification of DMD mutations in manifesting carriers, and confirm the heterogeneity of mutational mechanisms as well as the wide spectrum of phenotypes. 2010 Elsevier B.V. All rights reserved.

  9. GZF1 Mutations Expand the Genetic Heterogeneity of Larsen Syndrome.

    Science.gov (United States)

    Patel, Nisha; Shamseldin, Hanan E; Sakati, Nadia; Khan, Arif O; Softa, Ameen; Al-Fadhli, Fatima M; Hashem, Mais; Abdulwahab, Firdous M; Alshidi, Tarfa; Alomar, Rana; Alobeid, Eman; Wakil, Salma M; Colak, Dilek; Alkuraya, Fowzan S

    2017-05-04

    Larsen syndrome is characterized by the dislocation of large joints and other less consistent clinical findings. Heterozygous FLNB mutations account for the majority of Larsen syndrome cases, but biallelic mutations in CHST3 and B4GALT7 have been more recently described, thus confirming the existence of recessive forms of the disease. In a multiplex consanguineous Saudi family affected by severe and recurrent large joint dislocation and severe myopia, we identified a homozygous truncating variant in GZF1 through a combined autozygome and exome approach. Independently, the same approach identified a second homozygous truncating GZF1 variant in another multiplex consanguineous family affected by severe myopia, retinal detachment, and milder skeletal involvement. GZF1 encodes GDNF-inducible zinc finger protein 1, a transcription factor of unknown developmental function, which we found to be expressed in the eyes and limbs of developing mice. Global transcriptional profiling of cells from affected individuals revealed a shared pattern of gene dysregulation and significant enrichment of genes encoding matrix proteins, including P3H2, which hints at a potential disease mechanism. Our results suggest that GZF1 mutations cause a phenotype of severe myopia and significant articular involvement not previously described in Larsen syndrome. Copyright © 2017 American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  10. p53 inactivation upregulates p73 expression through E2F-1 mediated transcription.

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    Chaitali Tophkhane

    Full Text Available While p73 overexpression has been associated with increased apoptosis in cancer tissues, p73 overexpressing tumors appear to be of high grade malignancy. Why this putative tumor suppressor is overexpressed in cancer cells and what the function of overexpressed p73 is in breast cancers are critical questions to be addressed. By investigating the effect of p53 inactivation on p73 expression, we found that both protein and mRNA levels of TAp73 were increased in MCF-7/p53siRNA cells, MCF-7/p53mt135 cells and HCT-116/p53-/- cells, as compared to wild type control, suggesting that p53 inactivation by various forms upregulates p73. We showed that p53 knockdown induced p73 was mainly regulated at the transcriptional level. However, although p53 has a putative binding site in the TAp73 promoter, deletion of this binding site did not affect p53 knockdown mediated activation of TAp73 promoter. Chromatin immuno-precipitation (ChIP data demonstrated that loss of p53 results in enhanced occupancy of E2F-1 in the TAp73 promoter. The responsive sequence of p53 inactivation mediated p73 upregulation was mapped to the proximal promoter region of the TAp73 gene. To test the role of E2F-1 in p53 inactivation mediated regulation of p73 transcription, we found that p53 knockdown enhanced E2F-1 dependent p73 transcription, and mutations in E2F-1 binding sites in the TAp73 promoter abrogated p53 knockdown mediated activation of TAp73 promoter. Moreover, we demonstrated that p21 is a mediator of p53-E2F crosstalk in the regulation of p73 transcription. We concluded that p53 knockdown/inactivation may upregulate TAp73 expression through E2F-1 mediated transcriptional regulation. p53 inactivation mediated upregulation of p73 suggests an intrinsic rescuing mechanism in response to p53 mutation/inactivation. These findings support further analysis of the correlation between p53 status and p73 expression and its prognostic/predictive significance in human cancers.

  11. Hepatocellular carcinoma and the penetrance of HFE C282Y mutations: a cross sectional study

    Directory of Open Access Journals (Sweden)

    Lonsdale Ray

    2005-06-01

    Full Text Available Abstract Background Although most patients with hereditary haemochromatosis have HFE C282Y mutations, the lifetime risk to HFE C282Y homozygotes of developing fatal diseases such as hepatocellular carcinoma is uncertain. We have carried out a cross-sectional study to determine the proportion of diagnosed hepatocellular carcinoma patients who are homozygous for the HFE C282Y mutation; and to estimate the penetrance of this genotype with respect to hepatocellular carcinoma in East Anglia. Methods Tissue biopsies were analysed from 144 cases of hepatocellular carcinoma for HFE C282Y mutations; the data produced were compared with the frequency of HFE mutations in a large sample of the local population. Data were also retrieved from the East Anglian Cancer Intelligence Unit to determine the annual incidence of hepatocellular carcinoma; and from appropriate life tables. Results Eight out of 144 of the cases were homozygous for the HFE C282Y mutation, all 8 cases were male. 6 of these 8 cases had a previous diagnosis of hereditary haemochromatosis. Male HFE C282Y homozygotes were more likely to be diagnosed with hepatocellular carcinoma (odds ratio [OR] = 14, 95% confidence interval [CI] = 5–37. For this population, we estimate that the penetrance of the HFE C282Y homozygous genotype, with respect to hepatocellular carcinoma, was between 1.31 % and 2.1% for males and was zero for females. Conclusion In this population, we found that only a very small proportion of homozygotes for the HFE C282Y mutation developed hepatocellular carcinoma. However, individuals with this genotype have a significantly increased risk of this rare disease relative to those who do not carry the mutations.

  12. Inactivation of pathogenic bacteria in food matrices: high pressure processing, photodynamic inactivation and pressure-assisted photodynamic inactivation

    Science.gov (United States)

    Cunha, A.; Couceiro, J.; Bonifácio, D.; Martins, C.; Almeida, A.; Neves, M. G. P. M. S.; Faustino, M. A. F.; Saraiva, J. A.

    2017-09-01

    Traditional food processing methods frequently depend on the application of high temperature. However, heat may cause undesirable changes in food properties and often has a negative impact on nutritional value and organoleptic characteristics. Therefore, reducing the microbial load without compromising the desirable properties of food products is still a technological challenge. High-pressure processing (HPP) can be classified as a cold pasteurization technique, since it is a non-thermal food preservation method that uses hydrostatic pressure to inactivate spoilage microorganisms. At the same time, it increases shelf life and retains the original features of food. Photodynamic inactivation (PDI) is also regarded as promising approach for the decontamination of food matrices. In this case, the inactivation of bacterial cells is achieved by the cytotoxic effects of reactive oxygens species (ROS) produced from the combined interaction of a photosensitizer molecule, light and oxygen. This short review examines some recent developments on the application of HPP and PDI with food-grade photosensitizers for the inactivation of listeriae, taken as a food pathogen model. The results of a proof-of-concept trial of the use of high-pressure as a coadjutant to increase the efficiency of photodynamic inactivation of bacterial endospores is also addressed.

  13. Inactivation of the retinoblastoma gene yields a mouse model of malignant colorectal cancer.

    Science.gov (United States)

    Parisi, T; Bronson, R T; Lees, J A

    2015-11-26

    The retinoblastoma gene (Rb) is mutated at significant frequency in various human epithelial tumors, including colorectal cancer, and is strongly associated with metastatic disease. However, sole inactivation of Rb in the mouse has so far failed to yield epithelial cancers. Here, we specifically inactivate Rb and/or p53 in the urogenital epithelium and the intestine. We find that the loss of both tumor suppressors is unable to yield tumors in the transitional epithelium lining the bladder, kidneys and ureters. Instead, these mice develop highly metastatic tumors of neuroendocrine, not epithelial, origin within the urogenital tract to give prostate cancer in the males and vaginal tumors in the females. Additionally, we discovered that the sole inactivation of Rb in the intestine was sufficient to induce formation of metastatic colorectal adenocarcinomas. These tumors closely mirror the human disease in regard to the age of onset, histological appearance, invasiveness and metastatic potential. Like most human colorectal carcinomas, our murine Rb-deficient tumors demonstrate genomic instability and they show activation of β-catenin. Deregulation of the Wnt/β-catenin pathway is specific to the intestinal tumors, as genomic instability but not activation of β-catenin was observed in the neuroendocrine tumors. To date, attempts to generate genetically engineered mouse models of colorectal cancer tumors have yielded mostly cancer of the small intestine, which rarely occurs in humans. Our system provides the opportunity to accurately model and study colorectal cancer in the mouse via a single gene mutation.

  14. X-chromosomal inactivation directly influences the phenotypic manifestation of X-linked protoporphyria.

    Science.gov (United States)

    Brancaleoni, V; Balwani, M; Granata, F; Graziadei, G; Missineo, P; Fiorentino, V; Fustinoni, S; Cappellini, M D; Naik, H; Desnick, R J; Di Pierro, E

    2016-01-01

    X-linked protoporphyria (XLP), a rare erythropoietic porphyria, results from terminal exon gain-of-function mutations in the ALAS2 gene causing increased ALAS2 activity and markedly increased erythrocyte protoporphyrin levels. Patients present with severe cutaneous photosensitivity and may develop liver dysfunction. XLP was originally reported as X-linked dominant with 100% penetrance in males and females. We characterized 11 heterozygous females from six unrelated XLP families and show markedly varying phenotypic and biochemical heterogeneity, reflecting the degree of X-chromosomal inactivation of the mutant gene. ALAS2 sequencing identified the specific mutation and confirmed heterozygosity among the females. Clinical history, plasma and erythrocyte protoporphyrin levels were determined. Methylation assays of the androgen receptor and zinc-finger MYM type 3 short tandem repeat polymorphisms estimated each heterozygotes X-chromosomal inactivation pattern. Heterozygotes with equal or increased skewing, favoring expression of the wild-type allele had no clinical symptoms and only slightly increased erythrocyte protoporphyrin concentrations and/or frequency of protoporphyrin-containing peripheral blood fluorocytes. When the wild-type allele was preferentially inactivated, heterozygous females manifested the disease phenotype and had both higher erythrocyte protoporphyrin levels and circulating fluorocytes. These findings confirm that the previous dominant classification of XLP is inappropriate and genetically misleading, as the disorder is more appropriately designated XLP. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  15. CYP1B1 Mutations in Individuals With Primary Congenital Glaucoma and Residing in Denmark

    DEFF Research Database (Denmark)

    Grønskov, Karen; Redó-Riveiro, Alba; Sandfeld, Lisbeth

    2016-01-01

    in Denmark. The study included 37 unrelated individuals with PCG. Individuals were investigated for CYP1B1 mutations by Sanger sequencing of polymerase chain reaction products using BigDye terminators and capillary electrophoresis. A total of 12 mutations were identified and 5 of these were novel. Six were......Primary congenital glaucoma (PCG OMIM 231300) can be caused by pathogenic sequence variations in cytochrome P450, subfamily 1, polypeptide 1 (CYP1B1). The purpose of this study was to investigate the contribution of sequence variations in CYP1B1 in a cohort of individuals with PCG residing...... was homozygous and 1 was apparently homozygous. Three individuals were heterozygous for sequence variations in CYP1B1 thought to be pathogenic-one of these was p.(Tyr81Asn). Several known sequence variations with presumably no functional effect were found in the cohort. In this study, we identified 12 CYP1B1...

  16. Loss of Atrx affects trophoblast development and the pattern of X-inactivation in extraembryonic tissues.

    Directory of Open Access Journals (Sweden)

    David Garrick

    2006-04-01

    Full Text Available ATRX is an X-encoded member of the SNF2 family of ATPase/helicase proteins thought to regulate gene expression by modifying chromatin at target loci. Mutations in ATRX provided the first example of a human genetic disease associated with defects in such proteins. To better understand the role of ATRX in development and the associated abnormalities in the ATR-X (alpha thalassemia mental retardation, X-linked syndrome, we conditionally inactivated the homolog in mice, Atrx, at the 8- to 16-cell stage of development. The protein, Atrx, was ubiquitously expressed, and male embryos null for Atrx implanted and gastrulated normally but did not survive beyond 9.5 days postcoitus due to a defect in formation of the extraembryonic trophoblast, one of the first terminally differentiated lineages in the developing embryo. Carrier female mice that inherit a maternal null allele should be affected, since the paternal X chromosome is normally inactivated in extraembryonic tissues. Surprisingly, however, some carrier females established a normal placenta and appeared to escape the usual pattern of imprinted X-inactivation in these tissues. Together these findings demonstrate an unexpected, specific, and essential role for Atrx in the development of the murine trophoblast and present an example of escape from imprinted X chromosome inactivation.

  17. Novel mutations in CRB1 and ABCA4 genes cause Leber congenital amaurosis and Stargardt disease in a Swedish family.

    Science.gov (United States)

    Jonsson, Frida; Burstedt, Marie S; Sandgren, Ola; Norberg, Anna; Golovleva, Irina

    2013-11-01

    This study aimed to identify genetic mechanisms underlying severe retinal degeneration in one large family from northern Sweden, members of which presented with early-onset autosomal recessive retinitis pigmentosa and juvenile macular dystrophy. The clinical records of affected family members were analysed retrospectively and ophthalmological and electrophysiological examinations were performed in selected cases. Mutation screening was initially performed with microarrays, interrogating known mutations in the genes associated with recessive retinitis pigmentosa, Leber congenital amaurosis and Stargardt disease. Searching for homozygous regions with putative causative disease genes was done by high-density SNP-array genotyping, followed by segregation analysis of the family members. Two distinct phenotypes of retinal dystrophy, Leber congenital amaurosis and Stargardt disease were present in the family. In the family, four patients with Leber congenital amaurosis were homozygous for a novel c.2557C>T (p.Q853X) mutation in the CRB1 gene, while of two cases with Stargardt disease, one was homozygous for c.5461-10T>C in the ABCA4 gene and another was carrier of the same mutation and a novel ABCA4 mutation c.4773+3A>G. Sequence analysis of the entire ABCA4 gene in patients with Stargardt disease revealed complex alleles with additional sequence variants, which were evaluated by bioinformatics tools. In conclusion, presence of different genetic mechanisms resulting in variable phenotype within the family is not rare and can challenge molecular geneticists, ophthalmologists and genetic counsellors.

  18. Heavy ion induced mutation in arabidopsis

    Energy Technology Data Exchange (ETDEWEB)

    Tano, Shigemitsu [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    1997-03-01

    Heavy ions, He, C, Ar and Ne were irradiated to the seeds of Arabidopsis thaliana for inducing the new mutants. In the irradiated generation (M{sub 1}), germination and survival rate were observed to estimate the relative biological effectiveness in relation to the LET including the inactivation cross section. Mutation frequencies were compared by using three kinds of genetic loci after irradiation with C ions and electrons. Several interesting new mutants were selected in the selfed progenies of heavy ion irradiated seeds. (author)

  19. APOA5 Q97X mutation identified through homozygosity mapping causes severe hypertriglyceridemia in a Chilean consanguineous family.

    Science.gov (United States)

    Dussaillant, Catalina; Serrano, Valentina; Maiz, Alberto; Eyheramendy, Susana; Cataldo, Luis Rodrigo; Chavez, Matías; Smalley, Susan V; Fuentes, Marcela; Rigotti, Attilio; Rubio, Lorena; Lagos, Carlos F; Martinez, José Alfredo; Santos, José Luis

    2012-11-15

    Severe hypertriglyceridemia (HTG) has been linked to defects in LPL, APOC2, APOA5, LMF1 and GBIHBP1 genes. However, a number of severe HTG cases are probably caused by as yet unidentified mutations. Very high triglyceride plasma levels (>112 mmol/L at diagnosis) were found in two sisters of a Chilean consanguineous family, which is strongly suggestive of a recessive highly penetrant mutation. The aim of this study was to determine the genetic locus responsible for the severe HTG in this family. We carried out a genome-wide linkage study with nearly 300,000 biallelic markers (Illumina Human CytoSNP-12 panel). Using the homozygosity mapping strategy, we searched for chromosome regions with excess of homozygous genotypes in the affected cases compared to non-affected relatives. A large homozygous segment was found in the long arm of chromosome 11, with more than 2,500 consecutive homozygous SNP shared by the proband with her affected sister, and containing the APOA5/A4/C3/A1 cluster. Direct sequencing of the APOA5 gene revealed a known homozygous nonsense Q97X mutation (p.Gln97Ter) found in both affected sisters but not in non-affected relatives nor in a sample of unrelated controls. The Q97X mutation of the APOA5 gene in homozygous status is responsible for the severe hypertriglyceridemia in this family. We have shown that homozygosity mapping correctly pinpointed the genomic region containing the gene responsible for severe hypertriglyceridemia in this consanguineous Chilean family.

  20. APOA5 Q97X Mutation Identified through homozygosity mapping causes severe hypertriglyceridemia in a Chilean consanguineous family

    Directory of Open Access Journals (Sweden)

    Dussaillant Catalina

    2012-11-01

    Full Text Available Abstract Background Severe hypertriglyceridemia (HTG has been linked to defects in LPL, APOC2, APOA5, LMF1 and GBIHBP1 genes. However, a number of severe HTG cases are probably caused by as yet unidentified mutations. Very high triglyceride plasma levels (>112 mmol/L at diagnosis were found in two sisters of a Chilean consanguineous family, which is strongly suggestive of a recessive highly penetrant mutation. The aim of this study was to determine the genetic locus responsible for the severe HTG in this family. Methods We carried out a genome-wide linkage study with nearly 300,000 biallelic markers (Illumina Human CytoSNP-12 panel. Using the homozygosity mapping strategy, we searched for chromosome regions with excess of homozygous genotypes in the affected cases compared to non-affected relatives. Results A large homozygous segment was found in the long arm of chromosome 11, with more than 2,500 consecutive homozygous SNP shared by the proband with her affected sister, and containing the APOA5/A4/C3/A1 cluster. Direct sequencing of the APOA5 gene revealed a known homozygous nonsense Q97X mutation (p.Gln97Ter found in both affected sisters but not in non-affected relatives nor in a sample of unrelated controls. Conclusion The Q97X mutation of the APOA5 gene in homozygous status is responsible for the severe hypertriglyceridemia in this family. We have shown that homozygosity mapping correctly pinpointed the genomic region containing the gene responsible for severe hypertriglyceridemia in this consanguineous Chilean family.

  1. Characterization and mRNA expression analysis of a novel ARG1 splicing mutation causing hyperargininemia.

    Science.gov (United States)

    Villegas-Ruiz, Vanessa; Campos-Garcia, Felix J; Contreras-Capetillo, Silvina; Moreno-Graciano, Claudia M; Maldonado-Solis, Felipe A; Maldonado-Solis, Mario A; Zenteno, Juan C

    2015-12-01

    Biallelic mutations in the ARG1 gene result in an uncommon autosomal recessive inborn defect of the urea cycle known as hyperargininemia (OMIM #207800). ARG1 splicing mutations are not reported often, and they are probably related to a more severe phenotype than missense mutations. In this article, we describe the results of molecular studies in a young hyperargininemia patient carrying a novel splicing mutation in ARG1. Molecular analyses included PCR amplification and direct nucleotide sequencing of the ARG1 gene. RT-PCR analysis was performed to investigate the effect of the mutation in mRNA splicing and in the expression of ARG1 isoforms. Mutational analysis identified a novel homozygous ARG1 IVS4-1G>C point mutation in the patient's DNA. Blood leukocyte mRNA was analyzed to demonstrate the splicing defect caused by this mutation. Sequencing of ARG1 RT-PCR products allowed the characterization of a mutated transcript retaining 51-bp from intron 4. In addition, two new, alternatively spliced ARG1 transcripts lacking either exon 4 or exons 4 and 5 were identified in mRNA from the patient and from controls. Our results expand the mutational spectrum in hyperargininemia patients and indicate that the novel splicing mutation results in an aberrant transcript retaining intronic sequences. Two novel alternatively spliced ARG1 transcripts were also recognized. Copyright © 2015 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.

  2. A novel splicing mutation in GALT gene causing Galactosemia in Ecuadorian family.

    Science.gov (United States)

    De Lucca, M; Barba, C; Casique, L

    2017-07-01

    Classic Galactosemia (OMIM 230400) is an autosomal recessive disorder of galactose metabolism caused by mutations in the galactose-1-phosphate uridyl transferase (GALT) gene. This disease caused by the inability to metabolize galactose is potentially life-threatening but its pathophysiology has not been clearly defined. GALT gene presents high allelic heterogeneity and around 336 variations have been identified. Here, we report the case of a patient with Classic Galactosemia who was detected during a neonatal screening in Ecuador. Molecular study revealed a mutation in GALT gene intron 1, c.82+3A>G in homozygous condition, this mutation has not been previously reported. This gene variation was not found in any of the 119 healthy Ecuadorian individuals used as control. Furthermore, the mutation was the only alteration detected in the propositus's GALT after sequencing all exons and introns of this gene. In silico modeling predicted that the mutation was pathogenic. Copyright © 2017. Published by Elsevier B.V.

  3. Detection of five rare cystic fibrosis mutations peculiar to Southern Italy: implications in screening for the disease and phenotype characterization for patients with homozygote mutations.

    Science.gov (United States)

    Castaldo, G; Fuccio, A; Cazeneuve, C; Picci, L; Salvatore, D; Raia, V; Scarpa, M; Goossens, M; Salvatore, F

    1999-07-01

    The search for the eight most frequent mutations (i.e., DeltaF508, G542X, W1282X, N1303K, 1717-1G-->A, R553X, 2183AA-->G, and I148T) by allele-specific oligonucleotide dot-blot analysis revealed 78% of 396 cystic fibrosis alleles in Southern Italy. The observation of frequent haplotypes on the unidentified cystic fibrosis alleles suggested that a few mutations could account for a large number of unidentified alleles. We screened most of the coding sequence of the cystic fibrosis transmembrane regulator gene by denaturing gradient gel electrophoresis to determine the spectrum of these mutations in 68 unrelated cystic fibrosis patients bearing one or both unidentified mutations. The screening revealed five mutations, R1158X, 711+1G-->T, 4016insT, L1065P, and G1244E, each of which had a frequency of 1.3-1.8% (7% collectively). The 7% increase in the detection rate (85% vs 78%) reduces by >50% the residual risk of being cystic fibrosis carriers for couples who had tested negative by molecular analysis. We therefore designed a second allele-specific oligonucleotide set to analyze the five mutations. Among the patients analyzed, one patient homozygous for the L1065P mutation expressed a mild pulmonary and intestinal form of the disease with pancreatic insufficiency. Two other patients, homozygous for mutations R1158X and 4016insT, both expressed a severe cystic fibrosis phenotype. Five cystic fibrosis mutations are peculiar to patients from Southern Italy. The method described for their analysis is efficient, inexpensive, and can be semi-automated by use of a robotic workstation. The results obtained in patients from Southern Italy may have an impact on laboratories in other countries, given the large migrations of populations from Southern Italy to other countries in the last two centuries.

  4. Wolfram Syndrome: New Mutations, Different Phenotype

    Science.gov (United States)

    Pasquali, Lorenzo; Lugani, Francesca; Perri, Katia; Russo, Chiara; Tallone, Ramona; Ghiggeri, Gian Marco; Lorini, Renata; d'Annunzio, Giuseppe

    2012-01-01

    Background Wolfram Syndrome (WS) is an autosomal recessive neurodegenerative disorder characterized by Diabetes Insipidus, Diabetes Mellitus, Optic Atrophy, and Deafness identified by the acronym “DIDMOAD”. The WS gene, WFS1, encodes a transmembrane protein called Wolframin, which recent evidence suggests may serve as a novel endoplasmic reticulum calcium channel in pancreatic β-cells and neurons. WS is a rare disease, with an estimated prevalence of 1/550.000 children, with a carrier frequency of 1/354. The aim of our study was to determine the genotype of WS patients in order to establish a genotype/phenotype correlation. Methodology/Principal Findings We clinically evaluated 9 young patients from 9 unrelated families (6 males, 3 females). Basic criteria for WS clinical diagnosis were coexistence of insulin-treated diabetes mellitus and optic atrophy occurring before 15 years of age. Genetic analysis for WFS1 was performed by direct sequencing. Molecular sequencing revealed 5 heterozygous compound and 3 homozygous mutations. All of them were located in exon 8, except one in exon 4. In one proband only an heterozygous mutation (A684V) was found. Two new variants c.2663 C>A and c.1381 A>C were detected. Conclusions/Significance Our study increases the spectrum of WFS1 mutations with two novel variants. The male patient carrying the compound mutation [c.1060_1062delTTC]+[c.2663 C>A] showed the most severe phenotype: diabetes mellitus, optic atrophy (visual acuity 5/10), deafness with deep auditory bilaterally 8000 Hz, diabetes insipidus associated to reduced volume of posterior pituitary and pons. He died in bed at the age of 13 years. The other patient carrying the compound mutation [c.409_424dup16]+[c.1381 A>C] showed a less severe phenotype (DM, OA). PMID:22238590

  5. Autosomal recessive mutations in THOC6 cause intellectual disability: syndrome delineation requiring forward and reverse phenotyping.

    Science.gov (United States)

    Amos, J S; Huang, L; Thevenon, J; Kariminedjad, A; Beaulieu, C L; Masurel-Paulet, A; Najmabadi, H; Fattahi, Z; Beheshtian, M; Tonekaboni, S H; Tang, S; Helbig, K L; Alcaraz, W; Rivière, J-B; Faivre, L; Innes, A M; Lebel, R R; Boycott, K M

    2017-01-01

    THOC6 is a part of the THO complex, which is involved in coordinating mRNA processing with export. The THO complex interacts with additional components to form the larger TREX complex (transcription export complex). Previously, a homozygous missense mutation in THOC6 in the Hutterite population was reported in association with syndromic intellectual disability. Using exome sequencing, we identified three unrelated patients with bi-allelic mutations in THOC6 associated with intellectual disability and additional clinical features. Two of the patients were compound heterozygous for a stop and a missense mutation, and the third was homozygous for a missense mutation; the missense mutations were predicted to be pathogenic by in silico analysis and modeling. Clinical features of the three newly identified patients and those previously reported are reviewed; intellectual disability is moderate to severe, and malformations are variable including renal and heart defects, cleft palate, microcephaly, and corpus callosum dysgenesis. Facial features are variable and include tall forehead, short upslanting palpebral fissures +/- deep set eyes, and a long nose with overhanging columella. These subtle facial features render the diagnosis difficult to make in isolation with certainty. Our results expand the mutational and clinical spectrum of this rare disease, confirm that THOC6 is an intellectual disability causing gene, while providing insight into the importance of the THO complex in neurodevelopment. © 2016 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  6. Congenital Hereditary Endothelial Dystrophy Caused by SLC4A11 Mutations Progresses to Harboyan Syndrome

    Science.gov (United States)

    Siddiqui, Salina; Zenteno, Juan Carlos; Rice, Aine; Chacón-Camacho, Oscar; Naylor, Steven G.; Rivera-de la Parra, David; Spokes, David M.; James, Nigel; Toomes, Carmel; Inglehearn, Chris F.

    2013-01-01

    Purpose: Homozygous mutations in SLC4A11 cause 2 rare recessive conditions: congenital hereditary endothelial dystrophy (CHED), affecting the cornea alone, and Harboyan syndrome consisting of corneal dystrophy and sensorineural hearing loss. In addition, adult-onset Fuchs endothelial corneal dystrophy (FECD) is associated with dominant mutations in SLC4A11. In this report, we investigate whether patients with CHED go on to develop hearing loss and whether their parents, who are carriers of an SLC4A11 mutation, show signs of having FECD. Methods: Patients with CHED were screened for mutations in the SLC4A11 gene and underwent audiometric testing. The patients and their parents underwent a clinical examination and specular microscopy. Results: Molecular analyses confirmed SLC4A11 mutations in 4 affected individuals from 3 families. All the patients were found to have varying degrees of sensorineural hearing loss at a higher frequency range. Guttate lesions were seen in 2 of the 4 parents who were available for examination. Conclusions: Our observations suggest that CHED caused by homozygous SLC4A11 mutations progresses to Harboyan syndrome, but the severity of this may vary considerably. Patients with CHED should therefore be monitored for progressive hearing loss. We could not determine conclusively whether the parents of the patients with CHED were at increased risk of developing late-onset FECD. PMID:24351571

  7. A mutation in separase causes genome instability and increased susceptibility to epithelial cancer

    OpenAIRE

    Shepard, Jennifer L.; Amatruda, James F.; Finkelstein, David; Ziai, James; Finley, K. Rose; Stern, Howard M.; Chiang, Ken; Hersey, Candace; Barut, Bruce; Freeman, Jennifer L.; Lee, Charles; Glickman, Jonathan N.; Kutok, Jeffery L; Aster, Jon C; Zon, Leonard I.

    2007-01-01

    Proper chromosome segregation is essential for maintenance of genomic integrity and instability resulting from failure of this process may contribute to cancer. Here, we demonstrate that a mutation in the mitotic regulator separase is responsible for the cell cycle defects seen in the zebrafish mutant, cease&desist (cds). Analysis of cds homozygous mutant embryos reveals high levels of polyploidy and aneuploidy, spindle defects, and a mitotic exit delay. Carcinogenesis studies demonstrated th...

  8. Mutations in PCYT1A Cause Spondylometaphyseal Dysplasia with Cone-Rod Dystrophy

    OpenAIRE

    Yamamoto, Guilherme L.; Baratela, Wagner A.R.; Almeida, Tatiana F.; Lazar, Monize; Afonso, Clara L.; Oyamada, Maria K.; Suzuki, Lisa; Oliveira, Luiz A.N.; Ramos, Ester S.; Kim, Chong A.; Passos-Bueno, Maria Rita; Bertola, Débora R.

    2014-01-01

    Spondylometaphyseal dysplasia with cone-rod dystrophy is a rare autosomal-recessive disorder characterized by severe short stature, progressive lower-limb bowing, flattened vertebral bodies, metaphyseal involvement, and visual impairment caused by cone-rod dystrophy. Whole-exome sequencing of four individuals affected by this disorder from two Brazilian families identified two previously unreported homozygous mutations in PCYT1A. This gene encodes the alpha isoform of the phosphate cytidylylt...

  9. Kinetics of Hydrothermal Inactivation of Endotoxins ▿

    Science.gov (United States)

    Li, Lixiong; Wilbur, Chris L.; Mintz, Kathryn L.

    2011-01-01

    A kinetic model was established for the inactivation of endotoxins in water at temperatures ranging from 210°C to 270°C and a pressure of 6.2 × 106 Pa. Data were generated using a bench scale continuous-flow reactor system to process feed water spiked with endotoxin standard (Escherichia coli O113:H10). Product water samples were collected and quantified by the Limulus amebocyte lysate assay. At 250°C, 5-log endotoxin inactivation was achieved in about 1 s of exposure, followed by a lower inactivation rate. This non-log-linear pattern is similar to reported trends in microbial survival curves. Predictions and parameters of several non-log-linear models are presented. In the fast-reaction zone (3- to 5-log reduction), the Arrhenius rate constant fits well at temperatures ranging from 120°C to 250°C on the basis of data from this work and the literature. Both biphasic and modified Weibull models are comparable to account for both the high and low rates of inactivation in terms of prediction accuracy and the number of parameters used. A unified representation of thermal resistance curves for a 3-log reduction and a 3 D value associated with endotoxin inactivation and microbial survival, respectively, is presented. PMID:21193667

  10. Incidence of the endothelin receptor B mutation that causes lethal white foal syndrome in white-patterned horses.

    Science.gov (United States)

    Santschi, E M; Vrotsos, P D; Purdy, A K; Mickelson, J R

    2001-01-01

    To determine incidence of the Ile118Lys endothelin receptor B (EDNRB) mutation responsible for overo lethal white syndrome (OLWS) and its association with specific types of white patterning. 945 horses of white-patterned bloodlines and 55 solid-colored horses of other breeds. Horses were genotyped by use of allele-specific polymerase chain reaction to determine incidence of the Ile118Lys EDNRB mutation. Genotypes detected were homozygous Ile118, homozygous Lys118, and heterozygous. All foals with OLWS were homozygous for the Ile118Lys EDNRB mutation, and adults that were homozygous were not found. White patterning was strongly associated with EDNRB genotype. Color patterns with highest incidence (> 94%) of heterozygotes were frame overo, highly white calico overo, and frame blend overo. White-patterned bloodlines with lowest incidence of heterozygotes (white calico overo, splashed white overo, nonframe blend overo, and breeding-stock solid. The mutation was not detected in solid-colored horses from breeds without white patterning. In homozygotes, the Ile118Lys EDNRB mutation causes OLWS. In heterozygotes, the mutation is usually responsible for a frame overo phenotype. The frame pattern can be combined with other white patterns, making accurate estimation of EDNRB genotype by visual inspection difficult. Wide range of incidence of heterozygotes in various subtypes of white-patterned horses indicates different genetic control of these color patterns. Determination of EDNRB genotype by use of a DNA-based test is the only way to determine with certainty whether white-patterned horses can produce a foal affected with OLWS.

  11. High prevalence of leptin and melanocortin-4 receptor gene mutations in children with severe obesity from Pakistani consanguineous families.

    Science.gov (United States)

    Saeed, Sadia; Butt, Taeed A; Anwer, Mehwish; Arslan, Muhammad; Froguel, Philippe

    2012-05-01

    Recessive or co-dominant single-gene mutations disrupting leptin melanocortin pathway cause severe obesity and hyperphagia. Since Pakistan has a very high rate of consanguinity, therefore, a significantly higher incidence of monogenic obesity is expected in its population. We have assessed the incidence of LEP and MC4R mutations and associated hormonal profiles, in a cohort of randomly selected Pakistani children with early onset of severe obesity. Sixty two unrelated children of consanguineous parents, with a weight-for-age percentile >97 were recruited in the study. Screening for mutations in the coding regions of LEP and MC4R was performed by direct sequencing. Serum hormone concentrations were determined by immunoassay. LEP mutations were found in 16.1% of the probands. Of these, 9 probands carried the homozygous frameshift mutation, G133_VfsX14, whereas one patient had a homozygous mutation involving deletion of 3 base pairs, (I35del). In these probands, leptin levels were very low or undetectable and insulin levels were increased in 33%. Homozygous MC4R mutations, M161T and I316S, identified separately in 2 subjects (3.2%), were associated with severe obesity, hyperphagia, hyperleptinemia and hyperinsulinemia. The heterozygous M161T sibling had normal body weight and hormone levels and the parents were only mildly overweight. Based on genetic analysis of LEP and MC4R genes only, we elucidated genetic causality of severe obesity in 20% of our patients confirming high prevalence of monogenic form of obesity in this consanguineous population. Co-dominancy of MC4R is exacerbated in this group with non-penetrance of obesity in heterozygous loss-of-function MC4R mutation carriers. The sub-ethnic specificity of LEP mutation, G133_VfsX14, suggests a founder effect. Copyright © 2012 Elsevier Inc. All rights reserved.

  12. Mutation Analysis of Consanguineous Moroccan Patients with Parkinson’s Disease Combining Microarray and Gene Panel

    Directory of Open Access Journals (Sweden)

    Ahmed Bouhouche

    2017-10-01

    Full Text Available During the last two decades, 15 different genes have been reported to be responsible for the monogenic form of Parkinson’s disease (PD, representing a worldwide frequency of 5–10%. Among them, 10 genes have been associated with autosomal recessive PD, with PRKN and PINK1 being the most frequent. In a cohort of 145 unrelated Moroccan PD patients enrolled since 2013, 19 patients were born from a consanguineous marriage, of which 15 were isolated cases and 4 familial. One patient was homozygous for the common LRRK2 G2019S mutation and the 18 others who did not carry this mutation were screened for exon rearrangements in the PRKN gene using Affymetrix Cytoscan HD microarray. Two patients were determined homozygous for PRKN exon-deletions, while another patient presented with compound heterozygous inheritance (3/18, 17%. Two other patients showed a region of homozygosity covering the 1p36.12 locus and were sequenced for the candidate PINK1 gene, which revealed two homozygous point mutations: the known Q456X mutation in exon 7 and a novel L539F variation in exon 8. The 13 remaining patients were subjected to next-generation sequencing (NGS that targeted a panel of 22 PD-causing genes and overlapping phenotypes. NGS data showed that two unrelated consanguineous patients with juvenile-onset PD (12 and 13 years carried the same homozygous stop mutation W258X in the ATP13A2 gene, possibly resulting from a founder effect; and one patient with late onset (76 years carried a novel heterozygous frameshift mutation in SYNJ1. Clinical analysis showed that patients with the ATP13A2 mutation developed juvenile-onset PD with a severe phenotype, whereas patients having either PRKN or PINK1 mutations displayed early-onset PD with a relatively mild phenotype. By identifying pathogenic mutations in 45% (8/18 of our consanguineous Moroccan PD series, we demonstrate that the combination of chromosomal microarray analysis and NGS is a powerful approach to

  13. Novel mutations of HSD17B3 in three Chinese patients with 46,XY Disorders of Sex Development.

    Science.gov (United States)

    Yu, Bingqing; Liu, Zhaoxiang; Mao, Jiangfeng; Wang, Xi; Zheng, Junjie; Xiong, Shuyu; Cui, Mingxuan; Ma, Wanlu; Huang, Qibin; Xu, Hongli; Huang, Bingkun; Nie, Min; Wu, Xueyan

    2017-10-01

    17β-Hydroxysteroid dehydrogenase type 3 (17β-HSD3) converts the inactive Δ4-androstenedione (A) to testosterone (T). Its deficiency is the most common testosterone biosynthesis defect that results in 46,XY Disorders Of Sex Development (DSD). However, the disease is difficult to distinguish from other 46,XY DSD for similar clinical phenotypes. Therefore, genetic testing provides good criteria for the diagnosis of the disease. In this study, HSD17B3 gene was examined in 3 unrelated Chinese patients with 46,XY DSD. Direct sequencing and quantitative PCR of HSD17B3 gene revealed the presence of a compound heterozygous mutation (p.I60T/exon1 deletion) in Patient 1, a homozygous (p.I60T) mutation in Patient 2 and a frameshift mutation (p.V25Efs∗54) and an exon1 deletion in Patient 3. All of the mutations have not been reported previously. These novel mutations may expand the mutation database of HSD17B3 gene and provide us new insights into the molecular mechanism of 17β-HSD3 deficiency. It is noteworthy that when direct sequence analysis showed a rare homozygous mutation in patients with non-consanguineous parents, "apparent homozygosity" should be taken into an account and the intragenic deletion should be screened. In addition, when single mutation was found in patients with disease in recessive heredity mode, the intragenic deletion should also be screened. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Two linked polymorphic mutations (A(TA)7TAA and T-3279G) of UGT1A1 as the principal cause of Gilbert syndrome.

    Science.gov (United States)

    Maruo, Yoshihiro; D'Addario, Carlos; Mori, Asami; Iwai, Masaru; Takahashi, Hiroko; Sato, Hiroshi; Takeuchi, Yoshihiro

    2004-11-01

    Gilbert syndrome is a mild hereditary unconjugated hyperbilirubinemia caused by mutations in the bilirubin UDP-glucuronosyltransferase gene (UGT1A1). The mutation, A(TA)7TAA, is thought to be the sole cause of the syndrome in Caucasians, but an enhancer polymorphism (T-3279G) that lowers transcriptional activity has recently been reported. We have tested the linkage of the two mutations in 11 Caucasians and 12 Japanese patients who were homozygous for A(TA)7TAA. All 23 patients were also homozygous for T-3279G, indicating that T-3279G and A(TA)7TAA were linked. The decrease in transcription caused by both mutations together may be essential to the syndrome.

  15. Effect of the proprotein convertase subtilisin/kexin 9 monoclonal antibody, AMG 145, in homozygous familial hypercholesterolemia.

    Science.gov (United States)

    Stein, Evan A; Honarpour, Narimon; Wasserman, Scott M; Xu, Feng; Scott, Rob; Raal, Frederick J

    2013-11-05

    Homozygous familial hypercholesterolemia is a rare, serious disorder with a substantial reduction in low-density lipoprotein (LDL) receptor function, severely elevated LDL cholesterol, cardiovascular disease, and often death in childhood. Response to conventional drug therapies is modest. Monoclonal antibodies to proprotein convertase subtilisin/kexin 9 (PCSK9) reduce LDL cholesterol in heterozygous familial hypercholesterolemia. The effect in homozygous familial hypercholesterolemia is unknown and uncertain. We evaluated the efficacy and safety of AMG 145 in an open-label, single-arm, multicenter, dose-scheduling pilot study in patients with homozygous familial hypercholesterolemia. Eight patients with LDL receptor-negative or -defective homozygous familial hypercholesterolemia on stable drug therapy were treated with subcutaneous 420 mg AMG 145 every 4 weeks for ≥12 weeks, followed by 420 mg AMG 145 every 2 weeks for an additional 12 weeks. All patients completed both treatment periods. Mean change from baseline in LDL cholesterol at week 12 was -16.5% (range, 5.2% to -43.6%; P=0.0781) and -13.9% (range, 39.9% to -43.3%; P=0.1484) with 4- and 2-week dosing, respectively. No reduction was seen in the 2 receptor-negative patients. Over the treatment periods, mean±SD LDL cholesterol reductions in the 6 LDL receptor-defective patients were 19.3±16% and 26.3±20% with 4- and 2-week dosing, respectively (P=0.0313 for both values), ranging from 4% to 48% with 2-week dosing. No serious side effects were reported. This study demonstrates significant and dose-related LDL cholesterol lowering with a PCSK9 monoclonal antibody in homozygous familial hypercholesterolemia patients with defective LDL receptor activity but no reduction in those who were receptor negative.

  16. MRI at 3 Tesla detects no evidence for ischemic brain damage in intensively treated patients with homozygous familial hypercholesterolemia

    Energy Technology Data Exchange (ETDEWEB)

    Schmitz, Stephan A.; O' Regan, Declan P.; Fitzpatrick, Julie; Hajnal, Joseph V. [Hammersmith Hospital Campus, Imaging Sciences Department, MRC Clinical Sciences Centre, Faculty of Medicine, Imperial College, London (United Kingdom); Neuwirth, Clare; Potter, Elizabeth; Tosi, Isabella; Naoumova, Rossi P. [MRC Clinical Sciences Centre, Clinical Research Facility, London (United Kingdom); Hammersmith Hospital, Lipid Clinic, London (United Kingdom)

    2007-11-15

    Homozygous familial hypercholesterolemia (FH) is considered a model disease for excessive plasma cholesterol levels. Patients with untreated homozygous FH have a markedly increased risk for premature atherosclerosis. The frequency and extent of ischemic brain damage detectable by high-field magnetic resonance imaging (MRI) after long-term intensive treatment are unknown. In a case control study, five patients with homozygous FH (one male and four females; mean age: 23.6 {+-} 9.2, range: 12-36 years; mean pre-treatment serum total cholesterol level: 26.9 {+-} 3.24 mmol/L; all patients with documented atherosclerotic plaques in the carotid arteries) and five age- and sex-matched healthy controls were studied. All patients had been on maximal lipid-lowering medication since early childhood, and four of them were also on treatment with low-density lipoprotein (LDL) apheresis at bi-weekly intervals. Brain MRI was performed at 3 Tesla field strength with fluid-attenuated T2-weighted inversion recovery and T1-weighted spin-echo MR pulse sequences and subsequently evaluated by two independent readers. The maximal lipid-lowering treatment reduced the total serum cholesterol by more than 50% in the patients, but their serum concentrations were still 3.6-fold higher than those found in the controls (11.9 {+-} 4.2 vs. 4.5 {+-} 0.5 mmol/L; p < 0.0047). No brain abnormality was observed in any of the patients with homozygous FH. Homozygous FH patients on intensive cholesterol-lowering therapy have no evidence of ischemic brain damage at 3 Tesla MRI despite the remaining high cholesterol levels. (orig.)

  17. Inactivation of Transcriptional Regulators during Within-Household Evolution of Escherichia coli.

    Science.gov (United States)

    Kisiela, Dagmara I; Radey, Matthew; Paul, Sandip; Porter, Stephen; Polukhina, Kseniya; Tchesnokova, Veronika; Shevchenko, Sofiya; Chan, Diana; Aziz, Maliha; Johnson, Timothy J; Price, Lance B; Johnson, James R; Sokurenko, Evgeni V

    2017-07-01

    We analyzed the within-household evolution of two household-associated Escherichia coli strains from pandemic clonal group ST131-H30, using isolates recovered from five individuals within two families, each of which had a distinct strain. Family 1's strain was represented by a urine isolate from the index patient (older sister) with recurrent cystitis and a blood isolate from her younger sister with fatal urosepsis. Family 2's strain was represented by a urine isolate from the index patient (father) with pyelonephritis and renal abscesses, blood and kidney drainage isolates from the daughter with emphysematous pyelonephritis, and urine and fecal isolates from the mother with cystitis. Collectively, the several variants of each family's strain had accumulated a total of 8 (family 1) and 39 (family 2) point mutations; no two isolates were identical. Of the 47 total mutations, 36 resulted in amino acid changes or truncation of coded proteins. Fourteen such mutations (39%) targeted genes encoding transcriptional regulators, and 9 (25%) involved DNA-binding transcription factors (TFs), which significantly exceeded the relative contribution of TF genes to the isolates' genomes (∼6%). At least one-half of the transcriptional regulator mutations were inactivating, based on phenotypic and/or transcriptional analysis. In particular, inactivating mutations in the global regulator LrhA (repressor of type 1 fimbriae and flagella) occurred in the blood isolates from both households and increased the virulence of E. coli strains in a murine sepsis model. The results indicate that E. coli undergoes adaptive evolution between and/or within hosts, generating subpopulations with distinctive phenotypes and virulence potential.IMPORTANCE The clonal evolution of bacterial strains associated with interhost transmission is poorly understood. We characterized the genome sequences of clonal descendants of two Escherichia coli strains, recovered at different time points from multiple

  18. Loss-of-function mutations in SCN4A cause severe foetal hypokinesia or 'classical' congenital myopathy

    DEFF Research Database (Denmark)

    Zaharieva, Irina T; Thor, Michael G; Oates, Emily C

    2016-01-01

    and periodic paralysis. Using whole exome sequencing, we identified homozygous or compound heterozygous SCN4A mutations in a cohort of 11 individuals from six unrelated kindreds with congenital myopathy. Affected members developed in utero- or neonatal-onset muscle weakness of variable severity. In seven cases...

  19. Silent and symptomatic primary carnitine deficiency within the same family due to identical mutations in the organic cation/carnitine transporter OCTN2

    NARCIS (Netherlands)

    Spiekerkoetter, U.; Huener, G.; Baykal, T.; Demirkol, M.; Duran, M.; Wanders, R.; Nezu, J.; Mayatepek, E.

    2003-01-01

    A family of Turkish origin with primary systemic carnitine deficiency in the father and his two sons is described. In all three individuals, the same homozygous mutation in the OCTN2 gene (R471H) was present and carnitine uptake in fibroblasts was deficient. Whereas one boy became symptomatic with a

  20. Gene expression in hypothalamus, liver and adipose tissues and feed intake response to melanocortin-4 receptor (MC4R) agonist in pigs expressing (MC4R) mutations

    Science.gov (United States)

    Transcriptional profiling was used to identify genes and pathways that responded to intracerebroventricular (ICV) injection of melanocortin-4 receptor (MC4R) agonist, NDP-MSH, in pigs homozygous for the missense mutation in the MC4R, D298 allele (n = 12), N298 allele (n = 12) or heterozygous (n = 12...

  1. A novel treatment of cystic fibrosis acting on-target: cysteamine plus epigallocatechin gallate for the autophagy-dependent rescue of class II-mutated CFTR

    OpenAIRE

    Tosco, A.; De Gregorio, F.; Esposito, S.; Stefano, D; Sana, I; Ferrari, E.; Sepe, A.; Salvadori, L.; Buonpensiero, P.; Di Pasqua, A.; Grassia, R; Leone, C.A.; Guido, S; Rosa, G.; Lusa, S

    2016-01-01

    We previously reported that the combination of two safe proteostasis regulators, cysteamine and epigallocatechin gallate (EGCG), can be used to improve deficient expression of the cystic fibrosis transmembrane conductance regulator (CFTR) in patients homozygous for the CFTR Phe508del mutation. Here we provide the proof-of-concept that this combination treatment restored CFTR function and reduced lung inflammation (P

  2. Genetic mutations in early-onset Parkinson's disease Mexican patients: molecular testing implications.

    Science.gov (United States)

    Monroy-Jaramillo, Nancy; Guerrero-Camacho, Jorge Luis; Rodríguez-Violante, Mayela; Boll-Woehrlen, Marie-Catherine; Yescas-Gómez, Petra; Alonso-Vilatela, María Elisa; López-López, Marisol

    2014-04-01

    Mutations in PARK2, PINK1, and DJ-1 have been associated with autosomal recessive early-onset Parkinson's disease. Here, we report the prevalence of sequence and structural mutations in these three main recessive genes in Mexican Mestizo patients. The complete sequences of these three genes were analyzed by homo/heteroduplex DNA formation and direct sequencing; exon dosage was determined by multiplex ligation-dependent probe amplification and real-time PCR in 127 patients belonging to 122 families and 120 healthy Mexican Mestizo controls. All individuals had been previously screened for the three most common LRRK2 mutations. The presence of two mutations in compound heterozygous or homozygous genotypes was found in 16 unrelated patients, 10 had mutations in PARK2, six in PINK1, and none in DJ-1. Two PARK2-PINK1 and one PARK2-LRRK2 digenic cases were observed. Novel mutations were identified in PARK2 and PINK1 genes, including PINK1 duplication for the first time. Exon dosage deletions were the most frequent mutations in PARK2 (mainly in exons 9 and 12), followed by those in PINK1. The high prevalence of heterozygous mutations in PARK2 (12.3%) and the novel heterozygous and homozygous point mutations in PINK1 observed in familial and sporadic cases from various states of Mexico support the concept that single heterozygous mutations in recessive Parkinson's disease genes play a pathogenic role. These data have important implications for genetic counseling of Mexican Mestizo patients with early-onset Parkinson's disease. The presence of digenic inheritance underscores the importance of studying several genes in this disease. A step-ordered strategy for molecular diagnosis is proposed. © 2014 Wiley Periodicals, Inc.

  3. Clonal Heterogeneity Influences the Fate of New Adaptive Mutations

    Directory of Open Access Journals (Sweden)

    Ignacio Vázquez-García

    2017-10-01

    Full Text Available The joint contribution of pre-existing and de novo genetic variation to clonal adaptation is poorly understood but essential to designing successful antimicrobial or cancer therapies. To address this, we evolve genetically diverse populations of budding yeast, S. cerevisiae, consisting of diploid cells with unique haplotype combinations. We study the asexual evolution of these populations under selective inhibition with chemotherapeutic drugs by time-resolved whole-genome sequencing and phenotyping. All populations undergo clonal expansions driven by de novo mutations but remain genetically and phenotypically diverse. The clones exhibit widespread genomic instability, rendering recessive de novo mutations homozygous and refining pre-existing variation. Finally, we decompose the fitness contributions of pre-existing and de novo mutations by creating a large recombinant library of adaptive mutations in an ensemble of genetic backgrounds. Both pre-existing and de novo mutations substantially contribute to fitness, and the relative fitness of pre-existing variants sets a selective threshold for new adaptive mutations.

  4. Clinical characteristics and mutation analysis of propionic acidemia in Thailand.

    Science.gov (United States)

    Vatanavicharn, Nithiwat; Liammongkolkul, Somporn; Sakamoto, Osamu; Kamolsilp, Mahattana; Sathienkijkanchai, Achara; Wasant, Pornswan

    2014-02-01

    Propionic acidemia (PA) is caused by a deficiency of propionyl CoA carboxylase. A characteristic urine organic acid profile includes 3-hydroxypropionate, methylcitrate, tiglylglycine, and propionylglycine. The diagnosis of PA is confirmed by detection of mutations in the PCCA or PCCB genes. We herein report the clinical and molecular findings of four Thai patients with PA. Clinical findings of four Thai patients with PA were retrospectively reviewed. Urine organic acids were analyzed by gas chromatography-mass spectrometry. PCR-sequencing analyses of encoding exons and intron/exon boundaries of the PCCA and PCCB genes were performed. All patients had neonatal onset of PA. One patient died of cardiomyopathy, and another one of pneumonia and metabolic decompensation. The remainder experienced significant neurocognitive impairment. Mutation analysis of the PCCA gene identified homozygous c.1284+1G>A in patient 1, c.230G>A (p.R77Q) and c.1855C>T (p.R619X) in patient 2, homozygous c.2125T>C (p.S709P) in patient 3, and only one mutant allele, c.231+1G>T in patient 4. No PCCB mutation was identified. Four mutations including c.230G>A, c.231+1G>T, c.1855C>T, and c.2125T>C have not been reported previously. The clinical and molecular study of these Thai patients provided additional knowledge of the genotype and phenotype characteristics of PA. The results of the study suggested that PCCA mutations in Asian populations were distinct from those of other populations.

  5. phoU Inactivation in Pseudomonas aeruginosa Enhances Accumulation of ppGpp and Polyphosphate

    Science.gov (United States)

    de Almeida, Luiz Gustavo; Ortiz, Julia Helena; Schneider, René P.

    2015-01-01

    Inorganic polyphosphate (polyP) is a linear polymer composed of several molecules of orthophosphate (Pi) linked by energy-rich phosphoanhydride bonds. In Pseudomonas aeruginosa, Pi is taken up by the ABC transporter Pst, encoded by an operon consisting of five genes. The first four genes encode proteins involved in the transport of Pi and the last gene of the operon, phoU, codes for a protein which exact function is unknown. We show here that the inactivation of phoU in P. aeruginosa enhanced Pi removal from the medium and polyP accumulation. The phoU mutant also accumulated high levels of the alarmone guanosine tetraphosphate (ppGpp), which in turn increased the buildup of polyP. In addition, phoU inactivation had several pleiotropic effects, such as reduced growth rate and yield and increased sensitivity to antibiotics and stresses. However, biofilm formation was not affected by the phoU mutation. PMID:25710363

  6. Inactivation of glutathione peroxidase by benzaldehyde.

    Science.gov (United States)

    Tabatabaie, T; Floyd, R A

    1996-12-01

    Chronic benzaldehyde exposure is known to cause central nervous system (CNS) disturbances. Previous studies have shown that benzaldehyde causes the formation of reactive oxygen species (ROS) in rat synaptosomal fractions. Benzaldehyde has also been implicated in ROS formation in the CNS of rats treated with toluene. We have found that benzaldehyde effectively inactivates the antioxidant enzyme glutathione peroxidase (Ki approximately 15 microM), but has no effect on the other antioxidant enzymes tested: catalase, superoxide dismutase, and glutathione reductase. This effect has been found to be specific to benzaldehyde since other structurally related and unrelated aldehydes tested were found to be devoid of inactivating capacity toward glutathione peroxidase. Since glutathione peroxidase is the main enzyme responsible for removal of hydrogen peroxide and organic hydroperoxides in brain, its inactivation by benzaldehyde may be a main contributor to the observed ROS formation and the observed neurotoxicity caused by either benzaldehyde or toluene exposure.

  7. A Turkish family with Sjögren-Larsson syndrome caused by a novel ALDH3A2 mutation

    Directory of Open Access Journals (Sweden)

    Faruk Incecik

    2013-01-01

    Full Text Available Sjögren-Larsson syndrome (SLS is an inherited neurocutaneous disorder caused by mutations in the aldehyde dehydrogenase family 3 member A2 (ALDH3A2 gene that encodes fatty aldehyde dehydrogenase. Affected patients display ichthyosis, mental retardation, and spastic diplegia. More than 70 mutations in ALDH3A2 have been discovered in SLS patients. We diagnosed two brothers age of 12 and 20 years with characteristic features of this rare syndrome. Magnetic resonance imaging showed demyelinating disease in both of them. We described a novel homozygous, c. 835 T > A (p.Y279N mutation in exon 6 in two patients.

  8. Triple A or Allgrove syndrome. A case report with ophthalmic abnormalities and a novel mutation in the AAAS gene.

    Science.gov (United States)

    Villanueva-Mendoza, Cristina; artínez-Guzmán, Oswaldo; Rivera-Parra, David; Zenteno, Juan Carlos

    2009-03-01

    Triple A syndrome is a rare autosomal recessive disease characterized by achalasia, alacrima, adrenocorticotrophic hormone resistant adrenal failure and some neurologic abnormalities. We report a nine year old patient with alacrima, optic atrophy and achalasia with mutation in the AAAS gene. PCR amplification of the complete coding sequence as well as the exon-intron junctions of AAAS gene was performed in DNA from the patient and his parents. AAAS gene analysis demonstrated a homozygous A to G mutation at nucleotide position 122 in exon 1 in DNA from the patient. The novel mutation described confirms the diagnosis.

  9. Recessive mutations in PTHR1 cause contrasting skeletal dysplasias in Eiken and Blomstrand syndromes

    DEFF Research Database (Denmark)

    Duchatelet, Sabine; Ostergaard, Elsebet; Cortes, Dina

    2005-01-01

    Eiken syndrome is a rare autosomal recessive skeletal dysplasia. We identified a truncation mutation in the C-terminal cytoplasmic tail of the parathyroid hormone (PTH)/PTH-related peptide (PTHrP) type 1 receptor (PTHR1) gene as the cause of this syndrome. Eiken syndrome differs from Jansen...... and Blomstrand chondrodysplasia and from enchondromatosis, which are all syndromes caused by PTHR1 mutations. Notably, the skeletal features are opposite to those in Blomstrand chondrodysplasia, which is caused by inactivating recessive mutations in PTHR1. To our knowledge, this is the first description...... of opposite manifestations resulting from distinct recessive mutations in the same gene....

  10. Prenatal ultrasound monitoring of homozygous α0-thalassemia-induced fetal anemia.

    Science.gov (United States)

    Lee, Helena H L; Mak, Annisa S L; Poon, C F; Leung, K Y

    2017-02-01

    A noninvasive approach by serial ultrasound examination at 12-15, 18, and 30 weeks of gestation can be used to exclude homozygous α0-thalassemia-induced fetal anemia. At 12-15 weeks of gestation, the predictive values for the fetal cardio-thoracic ratio were better than that for the placental thickness. At 16-20 weeks of gestation, measuring middle cerebral artery peak systolic velocity is associated with a low false-positive rate. However, the false-positive rate of this noninvasive approach can be about 3%, requiring an invasive test to confirm the diagnosis. A false-negative may result in a delay in diagnosis. The success of this noninvasive approach depends on an accurate measurement of the fetal cardiothoracic ratio which can be improved by adequate training and subsequent quality control. Currently, there is a lack of data reporting the performance of a noninvasive approach before 12 weeks of gestation. Copyright © 2016. Published by Elsevier Ltd.

  11. Impact of LDL apheresis on aortic root atheroma in children with homozygous familial hypercholesterolemia.

    Science.gov (United States)

    Lefort, Bruno; Saheb, Samir; Bruckert, Eric; Giraud, Christine; Hequet, Olivier; Hankard, Régis

    2015-03-01

    Homozygous familial hypercholesterolemia (HFH) is a rare genetic disease leading to early onset atherosclerosis, due to high concentrations of LDL-C in the blood. Aortic root atheromas may be complicated by obstruction to left ventricle outflow or coronary stenosis. The aim of this study was to describe the progression of aortic root atheroma in patients requiring lipoprotein apheresis before 16 years of age and to examine the requirement of these patients for aortic surgery. Clinical reports, lipid profiles and echocardiogram results were obtained retrospectively for patients with HFH from three French hemapheresis centers. Data are presented as group medians. Twenty patients were included, of which 53% had aortic root atheroma (as assessed by echocardiogram) before starting lipoprotein apheresis. These patients began lipoprotein apheresis later than children without aortic root atheroma (10.3 years old [range 5.6-15.9 years] vs. 5.0 years old [range 4.5-11.6 years], respectively, p aortic root atheroma had progressed in 64% of patients. Five patients needed surgery for aortic stenosis, which was associated with a coronary artery by-pass for two of them. There were significantly more operations among patients with an aortic root atheroma at the beginning of lipoprotein apheresis than among patients without preexisting lesions (p aortic root atheroma should reduce the requirement for aortic surgery. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  12. Homozygous SMN2 deletion is a protective factor in the Swedish ALS population.

    Science.gov (United States)

    Corcia, Philippe; Ingre, Caroline; Blasco, Helene; Press, Rayomand; Praline, Julien; Antar, Catherine; Veyrat-Durebex, Charlotte; Guettard, Yves-Olivier; Camu, William; Andersen, Peter M; Vourc'h, Patrick; Andres, Christian R

    2012-05-01

    Abnormal survival motor neuron 1 (SMN1)-copy number has been associated with an increased risk of amyotrophic lateral sclerosis (ALS) in French and Dutch population studies. The aim of this study was to determine whether SMN gene copy number increases the risk of ALS or modulates its phenotype in a cohort of Swedish sporadic ALS (SALS) patients. In all, 502 Swedes with SALS and 502 Swedish controls matched for gender and age were enrolled. SMN1 and SMN2 gene copy numbers were studied by a semi-quantitative PCR method. A genotype-phenotype comparison was performed in order to determine whether SMN genes modulate the phenotype of ALS. The results were also compared with our previously reported French cohort of ALS patients. There was no difference between Swedish patients and controls in the frequency of SMN1 and SMN2 copy numbers. The frequency of SMN1 gene copies differed significantly between the French and Swedish ALS populations. The duration of the disease was significantly longer in the Swedish cohort with homozygous deletions of SMN2 when compared with the French cohort. Abnormal SMN1 gene copy number cannot be considered as a universal genetic susceptibility factor for SALS and this result underlines the importance of reproducing association gene studies in groups from different origins. We also suggest that SMN2 gene copy number might have different effects on ALS progression in disparate human populations.

  13. Homozygous hemoglobin S (HbSS) presenting with bilateral facial nerve palsy: a case report.

    Science.gov (United States)

    Ogundunmade, Babatunde Gbolahan; Jasper, Unyime Sunday

    2014-10-16

    Bilateral facial nerve palsy is a relatively rare presentation and often points to a serious underlying medical condition. Several studies have reported presentation of bilateral facial nerve palsy in association with Lyme disease, Guillain-Barre syndrome, systemic lupus erythematosus, human immunodeficiency virus, sarcoidosis, diabetes and Hanson disease. While unilateral facial nerve palsy is sometimes associated with hemiplegia in sickle cell patients, no case of bilateral facial nerve palsy have been reported in the literature. A 29-year-old black African woman who is a known homozygous haemoglobin S (HbSS) presented with bilateral facial nerve palsy. She had the said condition 2 months post delivery of her first child and reported for physiotherapy 3 months post incidence. The pre-treatment House Brackmann Facial Grading Scale (HBFGS) Scores were 3 for right side and 4 for left side. This patient was not on any medication for the facial palsy. After 4 sessions of combination therapy consisting of faradism, facial exercises and massage there was remarkable improvement in the neurological status of the facial muscles. The post treatment House Brackmann Facial Grading Scale score was 2 bilaterally. Bilateral facial nerve palsy may be an initial presentation of sickle cell anemia patients in the absence of other overt clinical presentations. Therefore sickle cell anemia should be considered among others, in the differential diagnosis of bilateral facial nerve palsy. Furthermore, this case report has highlighted the important role of physiotherapy in the management of bilateral facial nerve palsy.

  14. Homozygous sequence variants in the WNT10B gene underlie split hand/foot malformation

    Directory of Open Access Journals (Sweden)

    Asmat Ullah

    2018-01-01

    Full Text Available Abstract Split-hand/split-foot malformation (SHFM, also known as ectrodactyly is a rare genetic disorder. It is a clinically and genetically heterogeneous group of limb malformations characterized by absence/hypoplasia and/or median cleft of hands and/or feet. To date, seven genes underlying SHFM have been identified. This study described four consanguineous families (A-D segregating SHFM in an autosomal recessive manner. Linkage in the families was established to chromosome 12p11.1–q13.13 harboring WNT10B gene. Sequence analysis identified a novel homozygous nonsense variant (p.Gln154* in exon 4 of the WNT10B gene in two families (A and B. In the other two families (C and D, a previously reported variant (c.300_306dupAGGGCGG; p.Leu103Argfs*53 was detected. This study further expands the spectrum of the sequence variants reported in the WNT10B gene, which result in the split hand/foot malformation.

  15. Stanol esters attenuate the aggravating effect of dietary cholesterol on atherosclerosis in homozygous Watanabe rabbits

    DEFF Research Database (Denmark)

    Schrøder, Malene; Husche, Constanze; Pilegaard, Kirsten

    2009-01-01

    with dietary cholesterol. A total of 36 rabbits, 6 weeks of age, with initial plasma cholesterol of 22.5 mmol/L were assigned to two treatment groups fed a standard rabbit chow with 1 g/kg cholesterol or this diet added 34 g/kg stanol ester, respectively, for 16 weeks. Plasma cholesterol was measured initially......Plant stanols are marketed as natural means to lower blood cholesterol in humans; hence the effect on combined familial hyperlipidemia is not known. The objective was to investigate the effect of stanol esters on blood lipids and aortic atherosclerosis in homozygous WHHL rabbits challenged...... and at termination, also in lipoproteins. Aortic atherosclerosis was evaluated as cholesterol content and area covered by plaque. Plasma cholesterol was not significantly different between the groups at termination (35.7 mmol/L vs. 35.5 mmol/L). A significant increase in LDL was seen (13.1 mmol/L vs. 16.5 mmol...

  16. Pulmonary Embolism in a Sarcoidosis Patient Double Heterozygous for Methylenetetrahydrofolate Reductase Gene Polymorphisms and Factor V Leiden and Homozygous for the D-Allele of Angiotensin Converting Enzyme Gene

    Directory of Open Access Journals (Sweden)

    Nadim El-Majzoub

    2015-01-01

    Full Text Available Sarcoidosis is a multisystem granulomatous disease of unknown etiology and pathogenesis. It presents in patients younger than 40 years of age. The lungs are the most commonly affected organ. Till the present day, there is no single specific test that will accurately diagnose sarcoidosis; as a result, the diagnosis of sarcoidosis relies on a combination of clinical, radiologic, and histologic findings. Patients with sarcoidosis have been found to have an increased risk of pulmonary embolism compared to the normal population. MTHFR and factor V Leiden mutations have been reported to increase the risk of thrombosis in patients. We hereby present a case of a middle aged man with sarcoidosis who developed a right main pulmonary embolism and was found to be double heterozygous for methylenetetrahydrofolate reductase gene polymorphisms and factor V Leiden and homozygous for the D-allele of the angiotensin converting enzyme gene.

  17. Kinetics of Hydrothermal Inactivation of Endotoxins ▿

    OpenAIRE

    Li, Lixiong; Wilbur, Chris L.; Mintz, Kathryn L.

    2011-01-01

    A kinetic model was established for the inactivation of endotoxins in water at temperatures ranging from 210°C to 270°C and a pressure of 6.2 × 106 Pa. Data were generated using a bench scale continuous-flow reactor system to process feed water spiked with endotoxin standard (Escherichia coli O113:H10). Product water samples were collected and quantified by the Limulus amebocyte lysate assay. At 250°C, 5-log endotoxin inactivation was achieved in about 1 s of exposure, followed by a lower ina...

  18. Role of FAAH-like anandamide transporter in anandamide inactivation.

    Directory of Open Access Journals (Sweden)

    Kwannok Leung

    Full Text Available The endocannabinoid system modulates numerous physiological processes including nociception and reproduction. Anandamide (AEA is an endocannabinoid that is inactivated by cellular uptake followed by intracellular hydrolysis by fatty acid amide hydrolase (FAAH. Recently, FAAH-like anandamide transporter (FLAT, a truncated and catalytically-inactive variant of FAAH, was proposed to function as an intracellular AEA carrier and mediate its delivery to FAAH for hydrolysis. Pharmacological inhibition of FLAT potentiated AEA signaling and produced antinociceptive effects. Given that endocannabinoids produce analgesia through central and peripheral mechanisms, the goal of the current work was to examine the expression of FLAT in the central and peripheral nervous systems. In contrast to the original report characterizing FLAT, expression of FLAT was not observed in any of the tissues examined. To investigate the role of FLAT as a putative AEA binding protein, FLAT was generated from FAAH using polymerase chain reaction and further analyzed. Despite its low cellular expression, FLAT displayed residual catalytic activity that was sensitive to FAAH inhibitors and abolished following mutation of its catalytic serine. Overexpression of FLAT potentiated AEA cellular uptake and this appeared to be dependent upon its catalytic activity. Immunofluorescence revealed that FLAT localizes primarily to intracellular membranes and does not contact the plasma membrane, suggesting that its capability to potentiate AEA uptake may stem from its enzymatic rather than transport activity. Collectively, our data demonstrate that FLAT does not serve as a global intracellular AEA carrier, although a role in mediating localized AEA inactivation in mammalian tissues cannot be ruled out.

  19. MSA prions exhibit remarkable stability and resistance to inactivation.

    Science.gov (United States)

    Woerman, Amanda L; Kazmi, Sabeen A; Patel, Smita; Freyman, Yevgeniy; Oehler, Abby; Aoyagi, Atsushi; Mordes, Daniel A; Halliday, Glenda M; Middleton, Lefkos T; Gentleman, Steve M; Olson, Steven H; Prusiner, Stanley B

    2018-01-01

    In multiple system atrophy (MSA), progressive neurodegeneration results from the protein α-synuclein misfolding into a self-templating prion conformation that spreads throughout the brain. MSA prions are transmissible to transgenic (Tg) mice expressing mutated human α-synuclein (TgM83+/-), inducing neurological disease following intracranial inoculation with brain homogenate from deceased patient samples. Noting the similarities between α-synuclein prions and PrP scrapie (PrPSc) prions responsible for Creutzfeldt-Jakob disease (CJD), we investigated MSA transmission under conditions known to result in PrPSc transmission. When peripherally exposed to MSA via the peritoneal cavity, hind leg muscle, and tongue, TgM83+/- mice developed neurological signs accompanied by α-synuclein prions in the brain. Iatrogenic CJD, resulting from PrPSc prion adherence to surgical steel instruments, has been investigated by incubating steel sutures in contaminated brain homogenate before implantation into mouse brain. Mice studied using this model for MSA developed disease, whereas wire incubated in control homogenate had no effect on the animals. Notably, formalin fixation did not inactivate α-synuclein prions. Formalin-fixed MSA patient samples also transmitted disease to TgM83+/- mice, even after incubating in fixative for 244 months. Finally, at least 10% sarkosyl was found to be the concentration necessary to partially inactivate MSA prions. These results demonstrate the robustness of α-synuclein prions to denaturation. Moreover, they establish the parallel characteristics between PrPSc and α-synuclein prions, arguing that clinicians should exercise caution when working with materials that might contain α-synuclein prions to prevent disease.

  20. Inactivation of SDH and FH cause loss of 5hmC and increased H3K9me3 in paraganglioma/pheochromocytoma and smooth muscle tumors

    NARCIS (Netherlands)

    Hoekstra, A.S.; Graaff, M.A. de; Bruijn, I.H. Briaire-de; Ras, C.; Seifar, R.M.; Minderhout, I. van; Cornelisse, C.J.; Hogendoorn, P.C.; Breuning, M.H.; Suijker, J.; Korpershoek, E.; Kunst, H.P.M.; Frizzell, N.; Devilee, P.; Bayley, J.P.M.; Bovee, J.V.

    2015-01-01

    Succinate dehydrogenase (SDH) and fumarate hydratase (FH) are tricarboxylic acid (TCA) cycle enzymes and tumor suppressors. Loss-of-function mutations give rise to hereditary paragangliomas/pheochromocytomas and hereditary leiomyomatosis and renal cell carcinoma. Inactivation of SDH and FH results

  1. Inactivation of SDH and FH cause loss of 5hmC and increased H3K9me3 in paraganglioma/pheochromocytoma and smooth muscle tumors

    NARCIS (Netherlands)

    A.S. Hoekstra (Attje S.); M.A. de Graaff (Marieke A.); I.H. Briaire-de Bruijn (Inge H.); C. Ras (Cor); R.A. Seifar (Reza Maleki); I.J.H.M. van Minderhout (Ivonne); C.J. Cornelisse; P.C.W. Hogendoorn (Pancras C. W.); M.H. Breuning (Martijn); J. Suijker (Johnny); E. Korpershoek (Esther); H.P.M. Kunst (Henricus P.M.); N. Frizzell (Norma); P. Devilee (Peter); J.P. Bayley; J.V.M.G. Bovée (Judith)

    2015-01-01

    textabstractSuccinate dehydrogenase (SDH) and fumarate hydratase (FH) are tricarboxylic acid (TCA) cycle enzymes and tumor suppressors. Loss-of-function mutations give rise to hereditary paragangliomas/pheochromocytomas and hereditary leiomyomatosis and renal cell carcinoma. Inactivation of SDH and

  2. Studies of X inactivation and isodisomy in twins provide further evidence that the X chromosomes is not involved in Rett syndrome

    Energy Technology Data Exchange (ETDEWEB)

    Migeon, B.R.; Dunn, M.A.; Schmeckpeper, B.J.; Naidu, S. [Johns Hophins Univ., Baltimore, MD (United States); Thomas, G. [Johns Hopkins Univ., Baltimore, MD (United States)]|[Kennedy-Kreiger Institute, Baltimore, MD (United States)

    1995-03-01

    Rett syndrome (RS), a progressive encephalopathy with onset in infancy, has been attributed to an X-linked mutation, mainly on the basis of its occurrence almost exclusively in females and its concordance in female MZ twins. The underlying mechanisms proposed are an X-linked dominant mutation with male lethality, uniparental disomy of the X chromosome, and/or some disturbance in the process of X inactivation leading to unequal distribution of cells expressing maternal or paternal alleles (referred to as a {open_quotes}nonrandom{close_quotes} or {open_quotes}skewed {close_quotes} inactivation). To determine if the X chromosome is in fact involved in RS, we studied a group of affected females including three pairs of MZ twins, two concordant for RS and one uniquely discordant for RS. Analysis of X-inactivation patterns confirms the frequent nonrandom X inactivation previously observed in MZ twins but indicates that this is independent of RS. Analysis of 29 RS females reveals not one instance of uniparental X disomy, extending the observations previously reported. Therefore, our findings contribute no support for the hypothesis that RS is an X-linked disorder. Furthermore, the concordant phenotype in most MZ females twins with RS, which has not been observed in female twins with known X-linked mutations, argues against an X mutation. 41 refs., 2 figs.

  3. RB1 gene mutation up-date, a meta-analysis based on 932 reported mutations available in a searchable database

    Directory of Open Access Journals (Sweden)

    Pestaña Ángel

    2005-11-01

    Full Text Available Abstract Background Retinoblastoma, a prototype of hereditary cancer, is the most common intraocular tumour in children and potential cause of blindness from therapeutic eye ablation, second tumours in germ line carrier's survivors, and even death when left untreated. The molecular scanning of RB1 in search of germ line mutations lead to the publication of more than 900 mutations whose knowledge is important for genetic counselling and the characterization of phenotypic-genotypic relationships. Results A searchable database (RBGMdb has been constructed with 932 published RB1 mutations. The spectrum of these mutations has been analyzed with the following results: 1 the retinoblastoma protein is frequently inactivated by deletions and nonsense mutations while missense mutations are the main inactivating event in most genetic diseases. 2 Near 40% of RB1 gene mutations are recurrent and gather in sixteen hot points, including twelve nonsense, two missense and three splicing mutations. The remainder mutations are scattered along RB1, being most frequent in exons 9, 10, 14, 17, 18, 20, and 23. 3 The analysis of RB1 mutations by country of origin of the patients identifies two groups in which the incidence of nonsense and splicing mutations show differences extremely significant, and suggest the involvement of predisposing ethnic backgrounds. 4 A significant association between late age at diagnosis and splicing mutations in bilateral retinoblastoma patients suggests the occurrence of a delayed-onset genotype. 5 Most of the reported mutations in low-penetrance families fall in three groups: a Mutations in regulatory sequences at the promoter resulting in low expression of a normal Rb; b Missense and in-frame deletions affecting non-essential sequence motifs which result in a partial inactivation of Rb functions; c Splicing mutations leading to the reduction of normal mRNA splicing or to alternative splicing involving either true oncogenic or defective

  4. Homozygous premature truncation of the HERG protein : the human HERG knockout

    NARCIS (Netherlands)

    Hoorntje, T.; Alders, M.; van Tintelen, P.; van der Lip, K.; Sreeram, N.; van der Wal, A.; Mannens, M.; Wilde, A.

    1999-01-01

    Background-In long-QT syndrome (LQTS), heterozygosity for a mutation in 1 of the K(+) channel genes leads to prolongation of the cardiac action potential, because the aberrant protein exhibits "loss of function." HERG, which is involved in LQT2, is the gene encoding the rapid component of the

  5. Homozygous and heterozygous disruptions of ANK3: at the crossroads of neurodevelopmental and psychiatric disorders

    NARCIS (Netherlands)

    Iqbal, Z.; Vandeweyer, G.; Voet, M. van der; Waryah, A.M.; Zahoor, M.Y.; Besseling, J.A.; Roca, L.T.; Silfhout, A.T. van; Nijhof, B.; Kramer, J.M.; Aa, N. van der; Ansar, M.; Peeters, H.; Helsmoortel, C.; Gilissen, C.F.H.A.; Vissers, L.E.L.M.; Veltman, J.A.; Brouwer, A.P.M. de; Kooy, R. van; Riazuddin, S.; Schenck, A.; Bokhoven, H. van; Rooms, L.

    2013-01-01

    AnkyrinG, encoded by the ANK3 gene, is involved in neuronal development and signaling. It has previously been implicated in bipolar disorder and schizophrenia by association studies. Most recently, de novo missense mutations in this gene were identified in autistic patients. However, the causative

  6. Plasma lipoprotein(a) levels in patients with homozygous autosomal dominant hypercholesterolemia

    NARCIS (Netherlands)

    Sjouke, B.; Yahya, R.; Tanck, M.W.T.; Defesche, J.C.; Graaf, J. de; Wiegman, A.; Kastelein, J.J.; Mulder, M.T.; Hovingh, G.K.; Roeters van Lennep, J.E.

    2017-01-01

    BACKGROUND: Patients with autosomal dominant hypercholesterolemia (ADH), caused by mutations in either low-density lipoprotein receptor (LDLR), apolipoprotein B (APOB), or proprotein convertase subtilisin-kexin type 9 (PCSK9) are characterized by high low-density lipoprotein cholesterol levels and

  7. Inactivation of C4orf26 in toothless placental mammals.

    Science.gov (United States)

    Springer, Mark S; Starrett, James; Morin, Phillip A; Lanzetti, Agnese; Hayashi, Cheryl; Gatesy, John

    2016-02-01

    Previous studies have reported inactivated copies of six enamel-related genes (AMBN, AMEL, AMTN, ENAM, KLK4, MMP20) and one dentin-related gene (DSPP) in one or more toothless vertebrates and/or vertebrates with enamelless teeth, thereby providing evidence that these genes are enamel or tooth-specific with respect to their critical functions that are maintained by natural selection. Here, we employ available genome sequences for edentulous and enamelless mammals to evaluate the enamel specificity of four genes (WDR72, SLC24A4, FAM83H, C4orf26) that have been implicated in amelogenesis imperfecta, a condition in which proper enamel formation is abrogated during tooth development. Coding sequences for WDR72, SCL24A4, and FAM83H are intact in four edentulous taxa (Chinese pangolin, three baleen whales) and three taxa (aardvark, nine-banded armadillo, Hoffmann's two-toed sloth) with enamelless teeth, suggesting that these genes have critical functions beyond their involvement in tooth development. By contrast, genomic data for C4orf26 reveal inactivating mutations in pangolin and bowhead whale as well as evidence for deletion of this gene in two minke whale species. Hybridization capture of exonic regions and PCR screens provide evidence for inactivation of C4orf26 in eight additional baleen whale species. However, C4orf26 is intact in all three species with enamelless teeth that were surveyed, as well as in 95 additional mammalian species with enamel-capped teeth. Estimates of selection intensity suggest that dN/dS ratios on branches leading to taxa with enamelless teeth are similar to the dN/dS ratio on branches leading to taxa with enamel-capped teeth. Based on these results, we conclude that C4orf26 is tooth-specific, but not enamel-specific, with respect to its essential functions that are maintained by natural selection. A caveat is that an alternative splice site variant, which translates exon 3 in a different reading frame, is putatively functional in

  8. Disease-causing mutations in exon 11 of the medium-chain acyl-CoA dehydrogenase gene

    DEFF Research Database (Denmark)

    Andresen, B S; Jensen, T G; Bross, P

    1994-01-01

    . Our results show that exon 11 is not especially mutation prone. We demonstrate that two of the identified disease-causing mutations can be detected by restriction enzyme digestion of the PCR product from the assay for the G985 mutation, a discovery that makes this assay even more useful than before......Medium-chain acyl-CoA dehydrogenase (MCAD) deficiency is the most commonly recognized defect of the mitochondrial beta-oxidation in humans. It is a potentially fatal, autosomal recessive inherited defect. Most patients with MCAD deficiency are homozygous for a single disease-causing mutation (G985....... On the basis of expression of wild-type and mutant MCAD protein in COS-7 cells, we show that the identified mutations abolish MCAD enzyme activity and that they therefore must be disease causing. The M301T, S311R, and K304E mutations are located in helix H, which makes up part of the dimer-dimer interface...

  9. Generalized pustular psoriasis in infant with heterozygous mutation in the IL36RN gene successfully treated with infliximab

    DEFF Research Database (Denmark)

    Glerup, Mia; Herlin, Troels; Veirum, Jens Erik

    or DITRA genetic testing for IL1RN and IL36RN gene mutations was initiated. The girl was found to be heterozygous for a mutation in the IL36RN gene (exon 5, c 338C>T p Ser113Leu) whereas the IL1RN gene (mutated in DIRA patients) was normal. Additionally, a heterozygous mutation in the NLRP3 gene was also......Generalized pustular psoriasis in infant with heterozygous mutation in the IL36RN gene successfully treated with infliximab.M. Glerup1, J.E. Veirum1, L. Iversen2, M. Christiansen3, T. Herlin1.Departments of 1Pediatrics and 2Dermatology, and 3Clinical Immunology, Aarhus University Hospital, Denmark...... Background: Homozygous missense mutation in the IL36RN gene resulting in deficiency of interleukin-36-receptor antagonist (DITRA) is phenotypically presented as severe generalized pustular psoriasis starting in early childhood. Compound heterozygous cases have been described with the same DITRA phenotype...

  10. Identification of a breast cancer family double heterozygote for RAD51C and BRCA2 gene mutations

    DEFF Research Database (Denmark)

    Ahlborn, Lise B; Steffensen, Ane Y; Jønson, Lars

    2015-01-01

    Next-generation sequencing has entered routine genetic testing of hereditary breast cancer. It has provided the opportunity to screen multiple genes simultaneously, and consequently has identified new complex genotypes. Here we report the first identification of a woman double heterozygote...... for mutations in the RAD51C and BRCA2 genes. The RAD51C missense mutation p.Arg258His has previously been identified in a homozygous state in a patient with Fanconi anemia. This mutation is known to affect the DNA repair function of the RAD51C protein. The BRCA2 p.Leu3216Leu synonymous mutation has not been...... described before and mini-gene splicing experiments revealed that the mutation results in skipping of exon 26 containing a part of the DNA-binding domain. We conclude that the woman has two potential disease-causing mutations and that predictive testing of family members should include both the RAD51C...

  11. Phenotypic diversity in patients with lipodystrophy associated with LMNA mutations.

    Science.gov (United States)

    Mory, Patricia B; Crispim, Felipe; Freire, Maria Beatriz S; Salles, João Eduardo N; Valério, Cynthia M; Godoy-Matos, Amelio F; Dib, Sérgio A; Moisés, Regina S

    2012-09-01

    Mutations in LMNA have been linked to diverse disorders called laminopathies, which display heterogeneous phenotypes and include diseases affecting muscles, axonal neurons, progeroid syndromes, and lipodystrophies. Among the lipodystrophies, LMNA mutations have been reported most frequently in patients with familial partial lipodystrophy (FPLD) of the Dunnigan variety; however, phenotypic heterogeneity in the pattern of body fat loss has been observed. In this study, we searched for LMNA mutations in patients with various forms of lipodystrophy. We studied 21 unrelated individuals with lipodystrophy. Subjects underwent a complete clinical evaluation and were classified as typical FPLD (n=12), atypical partial lipodystrophy (n=7), or generalized lipodystrophy (n=2). Molecular analysis of LMNA gene, analysis of body fat by dual-energy X-ray absorptiometry, and biochemical measurements were performed. ALL PATIENTS WITH TYPICAL FPLD WERE FOUND TO CARRY LMNA MUTATIONS: seven patients harbored the heterozygous p.R482W (c.1444C>T), two patients harbored the p.R482Q (c.1445G>A), and two individuals harbored the novel heterozygous variant p.N466D (c.1396A>G), all in exon 8. Also, a homozygous p.R584H (c.1751 G>A) mutation in exon 11 was found. Among patients with atypical partial lipodystrophy, two of them were found to have LMNA mutations: a novel heterozygous p.R582C variation (c.1744 C>T) in exon 11 and a heterozygous substitution p.R349W (c.1045C>T) in exon 6. Among patients with generalized lipodystrophy, only one harbored LMNA mutation, a heterozygous p.T10I (c.29C>T) in exon 1. We have identified LMNA mutations in phenotypically diverse lipodystrophies. Also, our study broadens the spectrum of LMNA mutations in lipodystrophy.

  12. A rare homozygous MFSD8 single-base-pair deletion and frameshift in the whole genome sequence of a Chinese Crested dog with neuronal ceroid lipofuscinosis.

    Science.gov (United States)

    Guo, Juyuan; O'Brien, Dennis P; Mhlanga-Mutangadura, Tendai; Olby, Natasha J; Taylor, Jeremy F; Schnabel, Robert D; Katz, Martin L; Johnson, Gary S

    2015-01-03

    The neuronal ceroid lipofuscinoses are heritable lysosomal storage diseases characterized by progressive neurological impairment and the accumulation of autofluorescent storage granules in neurons and other cell types. Various forms of human neuronal ceroid lipofuscinosis have been attributed to mutations in at least 13 different genes. So far, mutations in the canine orthologs of 7 of these genes have been identified in DNA from dogs with neuronal ceroid lipofuscinosis. The identification of new causal mutations could lead to the establishment of canine models to investigate the pathogenesis of the corresponding human neuronal ceroid lipofuscinoses and to evaluate and optimize therapeutic interventions for these fatal human diseases. We obtained blood and formalin-fixed paraffin-embedded brain sections from a rescue dog that was reported to be a young adult Chinese Crested. The dog was euthanized at approximately 19 months of age as a consequence of progressive neurological decline that included blindness, anxiety, and cognitive impairment. A diagnosis of neuronal ceroid lipofuscinosis was made based on neurological signs, magnetic resonance imaging of the brain, and fluorescence microscopic and electron microscopic examination of brain sections. We isolate