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Sample records for gln1069arg mutation impairs

  1. Selected missense mutations impair frataxin processing in Friedreich ataxia.

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    Clark, Elisia; Butler, Jill S; Isaacs, Charles J; Napierala, Marek; Lynch, David R

    2017-08-01

    Frataxin (FXN) is a highly conserved mitochondrial protein. Reduced FXN levels cause Friedreich ataxia, a recessive neurodegenerative disease. Typical patients carry GAA repeat expansions on both alleles, while a subgroup of patients carry a missense mutation on one allele and a GAA repeat expansion on the other. Here, we report that selected disease-related FXN missense mutations impair FXN localization, interaction with mitochondria processing peptidase, and processing. Immunocytochemical studies and subcellular fractionation were performed to study FXN import into the mitochondria and examine the mechanism by which mutations impair FXN processing. Coimmunoprecipitation was performed to study the interaction between FXN and mitochondrial processing peptidase. A proteasome inhibitor was used to model traditional therapeutic strategies. In addition, clinical profiles of subjects with and without point mutations were compared in a large natural history study. FXN I 154F and FXN G 130V missense mutations decrease FXN 81-210 levels compared with FXN WT , FXN R 165C , and FXN W 155R , but do not block its association with mitochondria. FXN I 154F and FXN G 130V also impair FXN maturation and enhance the binding between FXN 42-210 and mitochondria processing peptidase. Furthermore, blocking proteosomal degradation does not increase FXN 81-210 levels. Additionally, impaired FXN processing also occurs in fibroblasts from patients with FXN G 130V . Finally, clinical data from patients with FXN G 130V and FXN I 154F mutations demonstrates a lower severity compared with other individuals with Friedreich ataxia. These data suggest that the effects on processing associated with FXN G 130V and FXN I 154F mutations lead to higher levels of partially processed FXN, which may contribute to the milder clinical phenotypes in these patients.

  2. Visual impairment in FOXG1-mutated individuals and mice.

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    Boggio, E M; Pancrazi, L; Gennaro, M; Lo Rizzo, C; Mari, F; Meloni, I; Ariani, F; Panighini, A; Novelli, E; Biagioni, M; Strettoi, E; Hayek, J; Rufa, A; Pizzorusso, T; Renieri, A; Costa, M

    2016-06-02

    The Forkead Box G1 (FOXG1 in humans, Foxg1 in mice) gene encodes for a DNA-binding transcription factor, essential for the development of the telencephalon in mammalian forebrain. Mutations in FOXG1 have been reported to be involved in the onset of Rett Syndrome, for which sequence alterations of MECP2 and CDKL5 are known. While visual alterations are not classical hallmarks of Rett syndrome, an increasing body of evidence shows visual impairment in patients and in MeCP2 and CDKL5 animal models. Herein we focused on the functional role of FOXG1 in the visual system of animal models (Foxg1(+/Cre) mice) and of a cohort of subjects carrying FOXG1 mutations or deletions. Visual physiology of Foxg1(+/Cre) mice was assessed by visually evoked potentials, which revealed a significant reduction in response amplitude and visual acuity with respect to wild-type littermates. Morphological investigation showed abnormalities in the organization of excitatory/inhibitory circuits in the visual cortex. No alterations were observed in retinal structure. By examining a cohort of FOXG1-mutated individuals with a panel of neuro-ophthalmological assessments, we found that all of them exhibited visual alterations compatible with high-level visual dysfunctions. In conclusion our data show that Foxg1 haploinsufficiency results in an impairment of mouse and human visual cortical function. Copyright © 2016 IBRO. Published by Elsevier Ltd. All rights reserved.

  3. Hearing impairment and renal failure associated with RMND1 mutations

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    Ravn, Kirstine; Neland, Mette; Wibrand, Flemming

    2016-01-01

    Recently, two research groups reported that mutations in RMND1 were associated with encephalopathy, elevated lactate, hypotonia, and in some patients seizures or myoclonia in individuals from two consanguineous families. A combined respiratory chain deficiency and a defect in mitochondrial protein...

  4. Autism-associated neuroligin-3 mutations commonly impair striatal circuits to boost repetitive behaviors.

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    Rothwell, Patrick E; Fuccillo, Marc V; Maxeiner, Stephan; Hayton, Scott J; Gokce, Ozgun; Lim, Byung Kook; Fowler, Stephen C; Malenka, Robert C; Südhof, Thomas C

    2014-07-03

    In humans, neuroligin-3 mutations are associated with autism, whereas in mice, the corresponding mutations produce robust synaptic and behavioral changes. However, different neuroligin-3 mutations cause largely distinct phenotypes in mice, and no causal relationship links a specific synaptic dysfunction to a behavioral change. Using rotarod motor learning as a proxy for acquired repetitive behaviors in mice, we found that different neuroligin-3 mutations uniformly enhanced formation of repetitive motor routines. Surprisingly, neuroligin-3 mutations caused this phenotype not via changes in the cerebellum or dorsal striatum but via a selective synaptic impairment in the nucleus accumbens/ventral striatum. Here, neuroligin-3 mutations increased rotarod learning by specifically impeding synaptic inhibition onto D1-dopamine receptor-expressing but not D2-dopamine receptor-expressing medium spiny neurons. Our data thus suggest that different autism-associated neuroligin-3 mutations cause a common increase in acquired repetitive behaviors by impairing a specific striatal synapse and thereby provide a plausible circuit substrate for autism pathophysiology. Copyright © 2014 Elsevier Inc. All rights reserved.

  5. Study of modifiers factors associated to mitochondrial mutations in individuals with hearing impairment

    International Nuclear Information System (INIS)

    Sousa de Moraes, Vanessa Cristine; Alexandrino, Fabiana; Andrade, Paula Baloni; Camara, Marilia Fontenele; Sartorato, Edi Lucia

    2009-01-01

    Hearing impairment is the most prevalent sensorial deficit in the general population. Congenital deafness occurs in about 1 in 1000 live births, of which approximately 50% has hereditary cause in development countries. Non-syndromic deafness can be caused by mutations in both nuclear and mitochondrial genes. Mutations in mtDNA have been associated with aminoglycoside-induced and non-syndromic deafness in many families worldwide. However, the nuclear background influences the phenotypic expression of these pathogenic mutations. Indeed, it has been proposed that nuclear modifier genes modulate the phenotypic manifestation of the mitochondrial A1555G mutation in the MTRNR1 gene. The both putative nuclear modifiers genes TRMU and MTO1 encoding a highly conserved mitochondrial related to tRNA modification. It has been hypothesizes that human TRMU and also MTO1 nuclear genes may modulate the phenotypic manifestation of deafness-associated mitochondrial mutations. The aim of this work was to elucidate the contribution of mitochondrial mutations, nuclear modifier genes mutations and aminoglycoside exposure in the deafness phenotype. Our findings suggest that the genetic background of individuals may play an important role in the pathogenesis of deafness-associated with mitochondrial mutation and aminoglycoside-induced.

  6. ADAM10 missense mutations potentiate β-amyloid accumulation by impairing prodomain chaperone function.

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    Suh, Jaehong; Choi, Se Hoon; Romano, Donna M; Gannon, Moira A; Lesinski, Andrea N; Kim, Doo Yeon; Tanzi, Rudolph E

    2013-10-16

    The generation of Aβ, the main component of senile plaques in Alzheimer's disease (AD), is precluded by α-secretase cleavage within the Aβ domain of the amyloid precursor protein (APP). We identified two rare mutations (Q170H and R181G) in the prodomain of the metalloprotease, ADAM10, that cosegregate with late-onset AD (LOAD). Here, we addressed the pathogenicity of these mutations in transgenic mice expressing human ADAM10 in brain. In Tg2576 AD mice, both mutations attenuated α-secretase activity of ADAM10 and shifted APP processing toward β-secretase-mediated cleavage, while enhancing Aβ plaque load and reactive gliosis. We also demonstrated ADAM10 expression potentiates adult hippocampal neurogenesis, which is reduced by the LOAD mutations. Mechanistically, both LOAD mutations impaired the molecular chaperone activity of ADAM10 prodomain. Collectively, these findings suggest that diminished α-secretase activity, owing to LOAD ADAM10 prodomain mutations, leads to AD-related pathology, strongly supporting ADAM10 as a promising therapeutic target for this devastating disease. Copyright © 2013 Elsevier Inc. All rights reserved.

  7. Impaired replication stress response in cells from immunodeficiency patients carrying Cernunnos/XLF mutations.

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    Michal Schwartz

    Full Text Available Non-Homologous End Joining (NHEJ is one of the two major pathways of DNA Double Strand Breaks (DSBs repair. Mutations in human NHEJ genes can lead to immunodeficiency due to its role in V(DJ recombination in the immune system. In addition, most patients carrying mutations in NHEJ genes display developmental anomalies which are likely the result of a general defect in repair of endogenously induced DSBs such as those arising during normal DNA replication. Cernunnos/XLF is a recently identified NHEJ gene which is mutated in immunodeficiency with microcephaly patients. Here we aimed to investigate whether Cernunnos/XLF mutations disrupt the ability of patient cells to respond to replication stress conditions. Our results demonstrate that Cernunnos/XLF mutated cells and cells downregulated for Cernunnos/XLF have increased sensitivity to conditions which perturb DNA replication. In addition, under replication stress, these cells exhibit impaired DSB repair and increased accumulation of cells in G2/M. Moreover Cernunnos/XLF mutated and down regulated cells display greater chromosomal instability, particularly at fragile sites, under replication stress conditions. These results provide evidence for the role of Cernunnos/XLF in repair of DSBs and maintenance of genomic stability under replication stress conditions. This is the first study of a NHEJ syndrome showing association with impaired cellular response to replication stress conditions. These findings may be related to the clinical features in these patients which are not due to the V(DJ recombination defect. Additionally, in light of the emerging important role of replication stress in the early stages of cancer development, our findings may provide a mechanism for the role of NHEJ in preventing tumorigenesis.

  8. Mutation of Dcdc2 in mice leads to impairments in auditory processing and memory ability.

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    Truong, D T; Che, A; Rendall, A R; Szalkowski, C E; LoTurco, J J; Galaburda, A M; Holly Fitch, R

    2014-11-01

    Dyslexia is a complex neurodevelopmental disorder characterized by impaired reading ability despite normal intellect, and is associated with specific difficulties in phonological and rapid auditory processing (RAP), visual attention and working memory. Genetic variants in Doublecortin domain-containing protein 2 (DCDC2) have been associated with dyslexia, impairments in phonological processing and in short-term/working memory. The purpose of this study was to determine whether sensory and behavioral impairments can result directly from mutation of the Dcdc2 gene in mice. Several behavioral tasks, including a modified pre-pulse inhibition paradigm (to examine auditory processing), a 4/8 radial arm maze (to assess/dissociate working vs. reference memory) and rotarod (to examine sensorimotor ability and motor learning), were used to assess the effects of Dcdc2 mutation. Behavioral results revealed deficits in RAP, working memory and reference memory in Dcdc2(del2/del2) mice when compared with matched wild types. Current findings parallel clinical research linking genetic variants of DCDC2 with specific impairments of phonological processing and memory ability. © 2014 John Wiley & Sons Ltd and International Behavioural and Neural Genetics Society.

  9. Intracellular HIV-1 Gag localization is impaired by mutations in the nucleocapsid zinc fingers

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    Muriaux Delphine

    2007-08-01

    Full Text Available Abstract Background The HIV-1 nucleocapsid protein (NC is formed of two CCHC zinc fingers flanked by highly basic regions. HIV-1 NC plays key roles in virus structure and replication via its nucleic acid binding and chaperoning properties. In fact, NC controls proviral DNA synthesis by reverse transcriptase (RT, gRNA dimerization and packaging, and virion assembly. Results We previously reported a role for the first NC zinc finger in virion structure and replication 1. To investigate the role of both NC zinc fingers in intracellular Gag trafficking, and in virion assembly, we generated series of NC zinc fingers mutations. Results show that all Zinc finger mutations have a negative impact on virion biogenesis and maturation and rendered defective the mutant viruses. The NC zinc finger mutations caused an intracellular accumulation of Gag, which was found either diffuse in the cytoplasm or at the plasma membrane but not associated with endosomal membranes as for wild type Gag. Evidences are also provided showing that the intracellular interactions between NC-mutated Gag and the gRNA were impaired. Conclusion These results show that Gag oligomerization mediated by gRNA-NC interactions is required for correct Gag trafficking, and assembly in HIV-1 producing cells and the release of infectious viruses.

  10. Hypomorphic mutation in mouse Nppc gene causes retarded bone growth due to impaired endochondral ossification

    International Nuclear Information System (INIS)

    Tsuji, Takehito; Kondo, Eri; Yasoda, Akihiro; Inamoto, Masataka; Kiyosu, Chiyo; Nakao, Kazuwa; Kunieda, Tetsuo

    2008-01-01

    Long bone abnormality (lbab/lbab) is a spontaneous mutant mouse characterized by dwarfism with shorter long bones. A missense mutation was reported in the Nppc gene, which encodes C-type natriuretic peptide (CNP), but it has not been confirmed whether this mutation is responsible for the dwarf phenotype. To verify that the mutation causes the dwarfism of lbab/lbab mice, we first investigated the effect of CNP in lbab/lbab mice. By transgenic rescue with chondrocyte-specific expression of CNP, the dwarf phenotype in lbab/lbab mice was completely compensated. Next, we revealed that CNP derived from the lbab allele retained only slight activity to induce cGMP production through its receptor. Histological analysis showed that both proliferative and hypertrophic zones of chondrocytes in the growth plate of lbab/lbab mice were markedly reduced. Our results demonstrate that lbab/lbab mice have a hypomorphic mutation in the Nppc gene that is responsible for dwarfism caused by impaired endochondral ossification

  11. VPS35 Deficiency or Mutation Causes Dopaminergic Neuronal Loss by Impairing Mitochondrial Fusion and Function

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    Fu-Lei Tang

    2015-09-01

    Full Text Available Vacuolar protein sorting-35 (VPS35 is a retromer component for endosomal trafficking. Mutations of VPS35 have been linked to familial Parkinson’s disease (PD. Here, we show that specific deletion of the VPS35 gene in dopamine (DA neurons resulted in PD-like deficits, including loss of DA neurons and accumulation of α-synuclein. Intriguingly, mitochondria became fragmented and dysfunctional in VPS35-deficient DA neurons, phenotypes that could be restored by expressing VPS35 wild-type, but not PD-linked mutant. Concomitantly, VPS35 deficiency or mutation increased mitochondrial E3 ubiquitin ligase 1 (MUL1 and, thus, led to mitofusin 2 (MFN2 degradation and mitochondrial fragmentation. Suppression of MUL1 expression ameliorated MFN2 reduction and DA neuron loss but not α-synuclein accumulation. These results provide a cellular mechanism for VPS35 dysfunction in mitochondrial impairment and PD pathogenesis.

  12. Retinitis Pigmentosa Mutations in Bad Response to Refrigeration 2 (Brr2) Impair ATPase and Helicase Activity.

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    Ledoux, Sarah; Guthrie, Christine

    2016-06-03

    Brr2 is an RNA-dependent ATPase required to unwind the U4/U6 snRNA duplex during spliceosome assembly. Mutations within the ratchet helix of the Brr2 RNA binding channel result in a form of degenerative human blindness known as retinitis pigmentosa (RP). The biochemical consequences of these mutations on Brr2's RNA binding, helicase, and ATPase activity have not yet been characterized. Therefore, we identified the largest construct of Brr2 that is soluble in vitro, which truncates the first 247 amino acids of the N terminus (Δ247-Brr2), to characterize the effects of the RP mutations on Brr2 activity. The Δ247-Brr2 RP mutants exhibit a gradient of severity of weakened RNA binding, reduced helicase activity, and reduced ATPase activity compared with wild type Δ247-Brr2. The globular C-terminal Jab1/Mpn1-like domain of Prp8 increases the ability of Δ247-Brr2 to bind the U4/U6 snRNA duplex at high pH and increases Δ247-Brr2's RNA-dependent ATPase activity and the extent of RNA unwinding. However, this domain of Prp8 does not differentially affect the Δ247-Brr2 RP mutants compared with the wild type Δ247-Brr2. When stimulated by Prp8, wild type Δ247-Brr2 is able to unwind long stable duplexes in vitro, and even the RP mutants capable of binding RNA with tight affinity are incapable of fully unwinding short duplex RNAs. Our data suggest that the RP mutations within the ratchet helix impair Brr2 translocation through RNA helices. © 2016 by The American Society for Biochemistry and Molecular Biology, Inc.

  13. Identification of a novel mutation in WFS1 in a family affected by low-frequency hearing impairment

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    Kunz, Juergen; Marquez-Klaka, Ben; Uebe, Steffen; Volz-Peters, Anja; Berger, Roswitha; Rausch, Peter

    2003-04-09

    Previously we confirmed linkage of autosomal dominantly inherited low-frequency sensorineural hearing impairment (LFSNHI) in a German family to the genetic locus DFNA6/DFNA14 on chromosome 4p16.3 close to the markers D4S432 and D4S431. Analysis of data from the Human Genome Project, showed that WFS1 is located in this region. Mutations in WFS1 are known to be responsible for Wolfram syndrome (DIDMOAD, MIM no. 606201), which follows an autosomal recessive trait. Studies in low-frequency hearing loss families showed that mutations in WFS1 were responsible for the phenotype. In all affected family members analysed, we detected a missense mutation in WFS1 (K705N) and therefore confirm the finding that the majority of mutations responsible for LFSNHI are missense mutations which localise to the C-terminal domain of the protein.

  14. Identification of a novel mutation in WFS1 in a family affected by low-frequency hearing impairment

    International Nuclear Information System (INIS)

    Kunz, Juergen; Marquez-Klaka, Ben; Uebe, Steffen; Volz-Peters, Anja; Berger, Roswitha; Rausch, Peter

    2003-01-01

    Previously we confirmed linkage of autosomal dominantly inherited low-frequency sensorineural hearing impairment (LFSNHI) in a German family to the genetic locus DFNA6/DFNA14 on chromosome 4p16.3 close to the markers D4S432 and D4S431. Analysis of data from the Human Genome Project, showed that WFS1 is located in this region. Mutations in WFS1 are known to be responsible for Wolfram syndrome (DIDMOAD, MIM no. 606201), which follows an autosomal recessive trait. Studies in low-frequency hearing loss families showed that mutations in WFS1 were responsible for the phenotype. In all affected family members analysed, we detected a missense mutation in WFS1 (K705N) and therefore confirm the finding that the majority of mutations responsible for LFSNHI are missense mutations which localise to the C-terminal domain of the protein

  15. Mutations in Alström protein impair terminal differentiation of cardiomyocytes.

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    Shenje, Lincoln T; Andersen, Peter; Halushka, Marc K; Lui, Cecillia; Fernandez, Laviel; Collin, Gayle B; Amat-Alarcon, Nuria; Meschino, Wendy; Cutz, Ernest; Chang, Kenneth; Yonescu, Raluca; Batista, Denise A S; Chen, Yan; Chelko, Stephen; Crosson, Jane E; Scheel, Janet; Vricella, Luca; Craig, Brian D; Marosy, Beth A; Mohr, David W; Hetrick, Kurt N; Romm, Jane M; Scott, Alan F; Valle, David; Naggert, Jürgen K; Kwon, Chulan; Doheny, Kimberly F; Judge, Daniel P

    2014-03-04

    Cardiomyocyte cell division and replication in mammals proceed through embryonic development and abruptly decline soon after birth. The process governing cardiomyocyte cell cycle arrest is poorly understood. Here we carry out whole-exome sequencing in an infant with evidence of persistent postnatal cardiomyocyte replication to determine the genetic risk factors. We identify compound heterozygous ALMS1 mutations in the proband, and confirm their presence in her affected sibling, one copy inherited from each heterozygous parent. Next, we recognize homozygous or compound heterozygous truncating mutations in ALMS1 in four other children with high levels of postnatal cardiomyocyte proliferation. Alms1 mRNA knockdown increases multiple markers of proliferation in cardiomyocytes, the percentage of cardiomyocytes in G2/M phases, and the number of cardiomyocytes by 10% in cultured cells. Homozygous Alms1-mutant mice have increased cardiomyocyte proliferation at 2 weeks postnatal compared with wild-type littermates. We conclude that deficiency of Alström protein impairs postnatal cardiomyocyte cell cycle arrest.

  16. Mutational spectrum of the WFS1 gene in Wolfram syndrome, nonsyndromic hearing impairment, diabetes mellitus, and psychiatric disease

    NARCIS (Netherlands)

    Cryns, K; Sivakumaran, TA; Van den Ouweland, JMW; Pennings, RJE; Cremers, CWRJ; Flothmann, K; Young, TL; Smith, RJH; Lesperance, MM; Van Camp, G

    2003-01-01

    WFS1 is a novel gene and encodes an 890 amino-acid glycoprotein (wolframin), predominantly localized in the endoplasmic reticulum. Mutations in WFS1 underlie autosomal recessive Wolfram syndrome and autosomal dominant low frequency sensorineural hearing impairment (LFSNHI) DFNA6/14. In addition,

  17. Mutational spectrum of the WFS1 gene in Wolfram syndrome, nonsyndromic hearing impairment, diabetes mellitus, and psychiatric disease.

    NARCIS (Netherlands)

    Cryns, K.; Sivakumaran, T.A.; Ouweland, J.M.W. van den; Pennings, R.J.E.; Cremers, C.W.R.J.; Flothmann, K.; Young, T.L.; Smith, R.J.H.; Lesperance, M.M.; Camp, G. van

    2003-01-01

    WFS1 is a novel gene and encodes an 890 amino-acid glycoprotein (wolframin), predominantly localized in the endoplasmic reticulum. Mutations in WFS1 underlie autosomal recessive Wolfram syndrome and autosomal dominant low frequency sensorineural hearing impairment (LFSNHI) DFNA6/14. In addition,

  18. Mutations affecting the SAND domain of DEAF1 cause intellectual disability with severe speech impairment and behavioral problems.

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    Vulto-van Silfhout, Anneke T; Rajamanickam, Shivakumar; Jensik, Philip J; Vergult, Sarah; de Rocker, Nina; Newhall, Kathryn J; Raghavan, Ramya; Reardon, Sara N; Jarrett, Kelsey; McIntyre, Tara; Bulinski, Joseph; Ownby, Stacy L; Huggenvik, Jodi I; McKnight, G Stanley; Rose, Gregory M; Cai, Xiang; Willaert, Andy; Zweier, Christiane; Endele, Sabine; de Ligt, Joep; van Bon, Bregje W M; Lugtenberg, Dorien; de Vries, Petra F; Veltman, Joris A; van Bokhoven, Hans; Brunner, Han G; Rauch, Anita; de Brouwer, Arjan P M; Carvill, Gemma L; Hoischen, Alexander; Mefford, Heather C; Eichler, Evan E; Vissers, Lisenka E L M; Menten, Björn; Collard, Michael W; de Vries, Bert B A

    2014-05-01

    Recently, we identified in two individuals with intellectual disability (ID) different de novo mutations in DEAF1, which encodes a transcription factor with an important role in embryonic development. To ascertain whether these mutations in DEAF1 are causative for the ID phenotype, we performed targeted resequencing of DEAF1 in an additional cohort of over 2,300 individuals with unexplained ID and identified two additional individuals with de novo mutations in this gene. All four individuals had severe ID with severely affected speech development, and three showed severe behavioral problems. DEAF1 is highly expressed in the CNS, especially during early embryonic development. All four mutations were missense mutations affecting the SAND domain of DEAF1. Altered DEAF1 harboring any of the four amino acid changes showed impaired transcriptional regulation of the DEAF1 promoter. Moreover, behavioral studies in mice with a conditional knockout of Deaf1 in the brain showed memory deficits and increased anxiety-like behavior. Our results demonstrate that mutations in DEAF1 cause ID and behavioral problems, most likely as a result of impaired transcriptional regulation by DEAF1. Copyright © 2014 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  19. Meta-analysis of SHANK Mutations in Autism Spectrum Disorders: a gradient of severity in cognitive impairments.

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    Leblond, Claire S; Nava, Caroline; Polge, Anne; Gauthier, Julie; Huguet, Guillaume; Lumbroso, Serge; Giuliano, Fabienne; Stordeur, Coline; Depienne, Christel; Mouzat, Kevin; Pinto, Dalila; Howe, Jennifer; Lemière, Nathalie; Durand, Christelle M; Guibert, Jessica; Ey, Elodie; Toro, Roberto; Peyre, Hugo; Mathieu, Alexandre; Amsellem, Frédérique; Rastam, Maria; Gillberg, I Carina; Rappold, Gudrun A; Holt, Richard; Monaco, Anthony P; Maestrini, Elena; Galan, Pilar; Heron, Delphine; Jacquette, Aurélia; Afenjar, Alexandra; Rastetter, Agnès; Brice, Alexis; Devillard, Françoise; Assouline, Brigitte; Laffargue, Fanny; Lespinasse, James; Chiesa, Jean; Rivier, François; Bonneau, Dominique; Regnault, Beatrice; Zelenika, Diana; Delepine, Marc; Lathrop, Mark; Sanlaville, Damien; Schluth-Bolard, Caroline; Edery, Patrick; Perrin, Laurence; Tabet, Anne Claude; Schmeisser, Michael J; Boeckers, Tobias M; Coleman, Mary; Sato, Daisuke; Szatmari, Peter; Scherer, Stephen W; Rouleau, Guy A; Betancur, Catalina; Leboyer, Marion; Gillberg, Christopher; Delorme, Richard; Bourgeron, Thomas

    2014-09-01

    SHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD), but their prevalence and clinical relevance remain to be determined. Here, we performed a new screen and a meta-analysis of SHANK copy-number and coding-sequence variants in ASD. Copy-number variants were analyzed in 5,657 patients and 19,163 controls, coding-sequence variants were ascertained in 760 to 2,147 patients and 492 to 1,090 controls (depending on the gene), and, individuals carrying de novo or truncating SHANK mutations underwent an extensive clinical investigation. Copy-number variants and truncating mutations in SHANK genes were present in ∼1% of patients with ASD: mutations in SHANK1 were rare (0.04%) and present in males with normal IQ and autism; mutations in SHANK2 were present in 0.17% of patients with ASD and mild intellectual disability; mutations in SHANK3 were present in 0.69% of patients with ASD and up to 2.12% of the cases with moderate to profound intellectual disability. In summary, mutations of the SHANK genes were detected in the whole spectrum of autism with a gradient of severity in cognitive impairment. Given the rare frequency of SHANK1 and SHANK2 deleterious mutations, the clinical relevance of these genes remains to be ascertained. In contrast, the frequency and the penetrance of SHANK3 mutations in individuals with ASD and intellectual disability-more than 1 in 50-warrant its consideration for mutation screening in clinical practice.

  20. Meta-analysis of SHANK Mutations in Autism Spectrum Disorders: a gradient of severity in cognitive impairments.

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    Claire S Leblond

    2014-09-01

    Full Text Available SHANK genes code for scaffold proteins located at the post-synaptic density of glutamatergic synapses. In neurons, SHANK2 and SHANK3 have a positive effect on the induction and maturation of dendritic spines, whereas SHANK1 induces the enlargement of spine heads. Mutations in SHANK genes have been associated with autism spectrum disorders (ASD, but their prevalence and clinical relevance remain to be determined. Here, we performed a new screen and a meta-analysis of SHANK copy-number and coding-sequence variants in ASD. Copy-number variants were analyzed in 5,657 patients and 19,163 controls, coding-sequence variants were ascertained in 760 to 2,147 patients and 492 to 1,090 controls (depending on the gene, and, individuals carrying de novo or truncating SHANK mutations underwent an extensive clinical investigation. Copy-number variants and truncating mutations in SHANK genes were present in ∼1% of patients with ASD: mutations in SHANK1 were rare (0.04% and present in males with normal IQ and autism; mutations in SHANK2 were present in 0.17% of patients with ASD and mild intellectual disability; mutations in SHANK3 were present in 0.69% of patients with ASD and up to 2.12% of the cases with moderate to profound intellectual disability. In summary, mutations of the SHANK genes were detected in the whole spectrum of autism with a gradient of severity in cognitive impairment. Given the rare frequency of SHANK1 and SHANK2 deleterious mutations, the clinical relevance of these genes remains to be ascertained. In contrast, the frequency and the penetrance of SHANK3 mutations in individuals with ASD and intellectual disability-more than 1 in 50-warrant its consideration for mutation screening in clinical practice.

  1. Alpha-synuclein mutations impair axonal regeneration in models of Parkinson´s disease

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    Lars eTönges

    2014-09-01

    Full Text Available The dopaminergic (DAergic nigrostriatal tract has an intrinsic regenerative capacity which can be impaired in Parkinson’s disease (PD. Alpha-synuclein (aSyn is a major pathogenic component in PD but its impact on DAergic axonal regeneration is largely unknown. In this study, we expressed pathogenic variants of human aSyn by means of recombinant adeno-associated viral vectors in experimental paradigms of DAergic regeneration. In a scratch lesion model in vitro, both aSyn(A30P and aSyn(A53T significantly reduced DAergic neurite regeneration and induced loss of TH-immunopositive cells while aSyn(WT showed only minor cellular neurotoxic effects. The striatal density of TH-immunopositive axons in the striatal 6-OHDA lesion mouse model was attenuated only by aSyn(A30P. However, striatal expression levels of the regeneration marker GAP-43 in TH-immunopositive fibers were reduced by both aSyn(A30P and aSyn(A53T, but not by aSyn(WT which was associated with an activation of the ROCK signaling pathway. Nigral DAergic cell loss was only mildly enhanced by additional overexpression of aSyn variants. Our findings indicate that mutations of aSyn have a strong impact on the regenerative capacity of DAergic neurons, which may contribute to their pathogenic effects.

  2. Molecular Etiology of Hearing Impairment in Inner Mongolia: mutations in SLC26A4 gene and relevant phenotype analysis

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    Wu Bailin

    2008-11-01

    Full Text Available Abstract Background The molecular etiology of hearing impairment in Chinese has not been thoroughly investigated. Study of GJB2 gene revealed that 30.4% of the patients with hearing loss in Inner Mongolia carried GJB2 mutations. The SLC26A4 gene mutations and relevant phenotype are analyzed in this study. Methods One hundred and thirty-five deaf patients were included. The coding exons of SLC26A4 gene were sequence analyzed in 111 patients, not including 22 patients carrying bi-allelic GJB2 mutations or one patient carrying a known GJB2 dominant mutation as well as one patient with mtDNA 1555A>G mutation. All patients with SLC26A4 mutations or variants were subjected to high resolution temporal bone CT scan and those with confirmed enlarged vestibular aqueduct and/or other inner ear malformation were then given further ultrasound scan of thyroid and thyroid hormone assays. Results Twenty-six patients (19.26%, 26/135 were found carrying SLC26A4 mutation. Among them, 17 patients with bi-allelic SLC26A4 mutations were all confirmed to have EVA or other inner ear malformation by CT scan. Nine patients were heterozygous for one SLC26A4 mutation, including 3 confirmed to be EVA or EVA and Mondini dysplasia by CT scan. The most common mutation, IVS7-2A>G, accounted for 58.14% (25/43 of all SLC26A4 mutant alleles. The shape and function of thyroid were confirmed to be normal by thyroid ultrasound scan and thyroid hormone assays in 19 of the 20 patients with EVA or other inner ear malformation except one who had cystoid change in the right side of thyroid. No Pendred syndrome was diagnosed. Conclusion In Inner Mongolia, China, mutations in SLC26A4 gene account for about 12.6% (17/135 of the patients with hearing loss. Together with GJB2 (23/135, SLC26A4 are the two most commonly mutated genes causing deafness in this region. Pendred syndrome is not detected in this deaf population. We established a new strategy that detects SLC26A4 mutations prior to the

  3. Molecular Etiology of Hearing Impairment in Inner Mongolia: mutations in SLC26A4 gene and relevant phenotype analysis

    Science.gov (United States)

    Dai, Pu; Yuan, Yongyi; Huang, Deliang; Zhu, Xiuhui; Yu, Fei; Kang, Dongyang; Yuan, Huijun; Wu, Bailin; Han, Dongyi; Wong, Lee-Jun C

    2008-01-01

    Background The molecular etiology of hearing impairment in Chinese has not been thoroughly investigated. Study of GJB2 gene revealed that 30.4% of the patients with hearing loss in Inner Mongolia carried GJB2 mutations. The SLC26A4 gene mutations and relevant phenotype are analyzed in this study. Methods One hundred and thirty-five deaf patients were included. The coding exons of SLC26A4 gene were sequence analyzed in 111 patients, not including 22 patients carrying bi-allelic GJB2 mutations or one patient carrying a known GJB2 dominant mutation as well as one patient with mtDNA 1555A>G mutation. All patients with SLC26A4 mutations or variants were subjected to high resolution temporal bone CT scan and those with confirmed enlarged vestibular aqueduct and/or other inner ear malformation were then given further ultrasound scan of thyroid and thyroid hormone assays. Results Twenty-six patients (19.26%, 26/135) were found carrying SLC26A4 mutation. Among them, 17 patients with bi-allelic SLC26A4 mutations were all confirmed to have EVA or other inner ear malformation by CT scan. Nine patients were heterozygous for one SLC26A4 mutation, including 3 confirmed to be EVA or EVA and Mondini dysplasia by CT scan. The most common mutation, IVS7-2A>G, accounted for 58.14% (25/43) of all SLC26A4 mutant alleles. The shape and function of thyroid were confirmed to be normal by thyroid ultrasound scan and thyroid hormone assays in 19 of the 20 patients with EVA or other inner ear malformation except one who had cystoid change in the right side of thyroid. No Pendred syndrome was diagnosed. Conclusion In Inner Mongolia, China, mutations in SLC26A4 gene account for about 12.6% (17/135) of the patients with hearing loss. Together with GJB2 (23/135), SLC26A4 are the two most commonly mutated genes causing deafness in this region. Pendred syndrome is not detected in this deaf population. We established a new strategy that detects SLC26A4 mutations prior to the temporal bone CT scan to

  4. A novel mutation in CDK5RAP2 gene causes primary microcephaly with speech impairment and sparse eyebrows in a consanguineous Pakistani family

    DEFF Research Database (Denmark)

    Abdullah, Uzma; Farooq, Muhammad; Mang, Yuan

    2017-01-01

    2 mutations is still under explored as only eleven families have been reported worldwide. Here, we analyzed a consanguineous Pakistani MCPH family, characterized by moderate to severe intellectual disability, speech impairment, moderately short stature and sparse eyebrows. Whole exome sequencing...

  5. Indian hedgehog mutations causing brachydactyly type A1 impair Hedgehog signal transduction at multiple levels

    Science.gov (United States)

    Ma, Gang; Yu, Jiang; Xiao, Yue; Chan, Danny; Gao, Bo; Hu, Jianxin; He, Yongxing; Guo, Shengzhen; Zhou, Jian; Zhang, Lingling; Gao, Linghan; Zhang, Wenjuan; Kang, Yan; Cheah, Kathryn SE; Feng, Guoyin; Guo, Xizhi; Wang, Yujiong; Zhou, Cong-zhao; He, Lin

    2011-01-01

    Brachydactyly type A1 (BDA1), the first recorded Mendelian autosomal dominant disorder in humans, is characterized by a shortening or absence of the middle phalanges. Heterozygous missense mutations in the Indian Hedgehog (IHH) gene have been identified as a cause of BDA1; however, the biochemical consequences of these mutations are unclear. In this paper, we analyzed three BDA1 mutations (E95K, D100E, and E131K) in the N-terminal fragment of Indian Hedgehog (IhhN). Structural analysis showed that the E95K mutation changes a negatively charged area to a positively charged area in a calcium-binding groove, and that the D100E mutation changes the local tertiary structure. Furthermore, we showed that the E95K and D100E mutations led to a temperature-sensitive and calcium-dependent instability of IhhN, which might contribute to an enhanced intracellular degradation of the mutant proteins via the lysosome. Notably, all three mutations affected Hh binding to the receptor Patched1 (PTC1), reducing its capacity to induce cellular differentiation. We propose that these are common features of the mutations that cause BDA1, affecting the Hh tertiary structure, intracellular fate, binding to the receptor/partners, and binding to extracellular components. The combination of these features alters signaling capacity and range, but the impact is likely to be variable and mutation-dependent. The potential variation in the signaling range is characterized by an enhanced interaction with heparan sulfate for IHH with the E95K mutation, but not the E131K mutation. Taken together, our results suggest that these IHH mutations affect Hh signaling at multiple levels, causing abnormal bone development and abnormal digit formation. PMID:21537345

  6. Dync1h1 Mutation Causes Proprioceptive Sensory Neuron Loss and Impaired Retrograde Axonal Transport of Dorsal Root Ganglion Neurons.

    Science.gov (United States)

    Zhao, Jing; Wang, Yi; Xu, Huan; Fu, Yuan; Qian, Ting; Bo, Deng; Lu, Yan-Xin; Xiong, Yi; Wan, Jun; Zhang, Xiang; Dong, Qiang; Chen, Xiang-Jun

    2016-07-01

    Sprawling (Swl) is a radiation-induced mutation which has been identified to have a nine base pair deletion in dynein heavy chain 1 (DYNC1H1: encoded by a single gene Dync1h1). This study is to investigate the phenotype and the underlying mechanism of the Dync1h1 mutant. To display the phenotype of Swl mutant mice, we examined the embryos of homozygous (Swl/Swl) and heterozygous (Swl/+) mice and their postnatal dorsal root ganglion (DRG) of surviving Swl/+ mice. The Swl/+ mice could survive for a normal life span, while Swl/Swl could only survive till embryonic (E) 8.5 days. Excessive apoptosis of Swl/+ DRG neurons was revealed during E11.5-E15.5 days, and the peak rate was at E13.5 days. In vitro study of mutated DRG neurons showed impaired retrograde transport of dynein-driven nerve growth factor (NGF). Mitochondria, another dynein-driven cargo, demonstrated much slower retrograde transport velocity in Swl/+ neurons than in wild-type (WT) neurons. Nevertheless, the Swl, Loa, and Cra mutations did not affect homodimerization of DYNC1H1. The Swl/Swl mutation of Dync1h1 gene led to embryonic mal-development and lethality, whereas the Swl/+ DRG neurons demonstrated deficient retrograde transport in dynein-driven cargos and excessive apoptosis during mid- to late-developmental stages. The underlying mechanism of the mutation may not be due to impaired homodimerization of DYNC1H1. © 2016 John Wiley & Sons Ltd.

  7. Manifestation of x-radiation induced sex-linked recessive lethal mutation impairing the development of imaginal disks and gonads in Drosophila Melanogaster

    International Nuclear Information System (INIS)

    Abeleva, Eh.A.; Ivanov, A.I.

    1982-01-01

    A study was made of Drosophila melanogaster mutations impairing the development of imaginal disks. The state of gonads in these mutants was not studied. Using X-radiation a lethal mutation in X chromosome was obtained that induced degeneration of imaginal disks at the 3d stage of larva development. The gonads of the mutants at this stage of development vary in size. The transplantation tests showed that the mutation manifests itself in both the imaginal disks and the gonads

  8. Sex-related hearing impairment in Wolfram syndrome patients identified by inactivating WFS1 mutations

    NARCIS (Netherlands)

    Pennings, RJE; Huygen, PLM; van den Ouweland, JMW; Cryns, K; Dikkeschei, LD; Van Camp, G; Cremers, CWRJ

    2004-01-01

    This study examined the audiovestibular profile of 11 Wolfram syndrome patients (4 males, 7 females) from 7 families, with identified WFS1 mutations, and the audiometric profile of 17 related heterozygous carriers of WFS1 mutations. Patients with Wolfram syndrome showed a downsloping audiogram and

  9. Sex-related hearing impairment in Wolfram syndrome patients identified by inactivating WFS1 mutations.

    NARCIS (Netherlands)

    Pennings, R.J.E.; Huygen, P.L.M.; Ouweland, J.M.W. van den; Cryns, K.; Dikkeschei, L.D.; Camp, G. van; Cremers, C.W.R.J.

    2004-01-01

    This study examined the audiovestibular profile of 11 Wolfram syndrome patients (4 males, 7 females) from 7 families, with identified WFS1 mutations, and the audiometric profile of 17 related heterozygous carriers of WFS1 mutations. Patients with Wolfram syndrome showed a downsloping audiogram and

  10. Axonal transport of TDP-43 mRNA granules in neurons is impaired by ALS-causing mutations

    Science.gov (United States)

    Carrasco, Monica A.; Williams, Luis A.; Winborn, Christina S.; Han, Steve S. W.; Kiskinis, Evangelos; Winborn, Brett; Freibaum, Brian D.; Kanagaraj, Anderson; Clare, Alison J.; Badders, Nisha M.; Bilican, Bilada; Chaum, Edward; Chandran, Siddharthan; Shaw, Christopher E.; Eggan, Kevin C.; Maniatis, Tom; Taylor, J. Paul

    2014-01-01

    Summary The RNA binding protein TDP-43 regulates RNA metabolism at multiple levels, including transcription, RNA splicing, and mRNA stability. TDP-43 is a major component of the cytoplasmic inclusions characteristic of amyotrophic lateral sclerosis and some types of frontotemporal lobar degeneration. The importance of TDP-43 in disease is underscored by the fact that dominant missense mutations are sufficient to cause disease, although the role of TDP-43 in pathogenesis is unknown. Here we show that TDP-43 forms cytoplasmic mRNP granules that undergo bidirectional, microtubule-dependent transport in neurons in vitro and in vivo and facilitate delivery of target mRNA to distal neuronal compartments. TDP-43 mutations impair this mRNA transport function in vivo and in vitro, including in stem cell-derived motor neurons from ALS patients bearing any one of three different TDP-43 ALS-causing mutations. Thus, TDP43 mutations that cause ALS lead to partial loss of a novel cytoplasmic function of TDP-43. PMID:24507191

  11. A Novel Locus Harbouring a Functional CD164 Nonsense Mutation Identified in a Large Danish Family with Nonsyndromic Hearing Impairment

    DEFF Research Database (Denmark)

    Nyegaard, Mette; Rendtorff, Nanna D; Nielsen, Morten S

    2015-01-01

    Nonsyndromic hearing impairment (NSHI) is a highly heterogeneous condition with more than eighty known causative genes. However, in the clinical setting, a large number of NSHI families have unexplained etiology, suggesting that there are many more genes to be identified. In this study we used SNP......-based linkage analysis and follow up microsatellite markers to identify a novel locus (DFNA66) on chromosome 6q15-21 (LOD 5.1) in a large Danish family with dominantly inherited NSHI. By locus specific capture and next-generation sequencing, we identified a c.574C>T heterozygous nonsense mutation (p.R192......-genome and exome sequence data. The predicted effect of the mutation was a truncation of the last six C-terminal residues of the cytoplasmic tail of CD164, including a highly conserved canonical sorting motif (YXX phi). In whole blood from an affected individual, we found by RT-PCR both the wild...

  12. Hearing impairment caused by mutations in two different genes responsible for nonsyndromic and syndromic hearing loss within a single family.

    Science.gov (United States)

    Niepokój, Katarzyna; Rygiel, Agnieszka M; Jurczak, Piotr; Kujko, Aleksandra A; Śniegórska, Dominika; Sawicka, Justyna; Grabarczyk, Alicja; Bal, Jerzy; Wertheim-Tysarowska, Katarzyna

    2018-02-01

    Usher syndrome is rare genetic disorder impairing two human senses, hearing and vision, with the characteristic late onset of vision loss. This syndrome is divided into three types. In all cases, the vision loss is postlingual, while loss of hearing is usually prelingual. The vestibular functions may also be disturbed in Usher type 1 and sometimes in type 3. Vestibular areflexia is helpful in making a proper diagnosis of the syndrome, but, often, the syndrome is misdiagnosed as a nonsyndromic hearing loss. Here, we present a Polish family with hearing loss, which was clinically classified as nonsyndromic. After excluding mutations in the DFNB1 locus, we implemented the next-generation sequencing method and revealed that hearing loss was syndromic and mutations in the USH2A gene indicate Usher syndrome. This research highlights the importance of molecular analysis in establishing a clinical diagnosis of congenital hearing loss.

  13. Homozygous SLC6A17 Mutations Cause Autosomal-Recessive Intellectual Disability with Progressive Tremor, Speech Impairment, and Behavioral Problems

    OpenAIRE

    Iqbal, Zafar; Willemsen, Marjolein H.; Papon, Marie-Amélie; Musante, Luciana; Benevento, Marco; Hu, Hao; Venselaar, Hanka; Wissink-Lindhout, Willemijn M.; Vulto-van Silfhout, Anneke T.; Vissers, Lisenka E.L.M.; de Brouwer, Arjan P.M.; Marouillat, Sylviane; Wienker, Thomas F.; Ropers, Hans Hilger; Kahrizi, Kimia

    2015-01-01

    We report on Dutch and Iranian families with affected individuals who present with moderate to severe intellectual disability and additional phenotypes including progressive tremor, speech impairment, and behavioral problems in certain individuals. A combination of exome sequencing and homozygosity mapping revealed homozygous mutations c.484G>A (p.Gly162Arg) and c.1898C>G (p.Pro633Arg) in SLC6A17. SLC6A17 is predominantly expressed in the brain, encodes a synaptic vesicular transporter of neu...

  14. Mitochondrial impairment observed in fibroblasts from South African Parkinson’s disease patients with parkin mutations

    Energy Technology Data Exchange (ETDEWEB)

    Merwe, Celia van der, E-mail: celiavdm@sun.ac.za [Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Loos, Ben [Department of Physiological Sciences, Faculty of Science, Stellenbosch University, Stellenbosch (South Africa); Swart, Chrisna [Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Kinnear, Craig [Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); MRC Centre for Molecular and Cellular Biology and the DST/NRF Centre of Excellence for Biomedical TB Research, Stellenbosch University, Cape Town (South Africa); Henning, Franclo [Division of Neurology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Merwe, Lize van der [Division of Molecular Biology and Human Genetics, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Department of Statistics, University of the Western Cape, Cape Town (South Africa); Pillay, Komala [National Health Laboratory Services (NHLS) Histopathology Laboratory, Red Cross Children’s Hospital, Cape Town (South Africa); Muller, Nolan [Division of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Zaharie, Dan [Neuropathology Unit, Division of Anatomical Pathology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); Engelbrecht, Lize [Cell Imaging Unit, Central Analytical Facility, Stellenbosch University, Cape Town (South Africa); Carr, Jonathan [Division of Neurology, Faculty of Medicine and Health Sciences, Stellenbosch University, Cape Town (South Africa); and others

    2014-05-02

    Highlights: • Mitochondrial dysfunction observed in patients with parkin-null mutations. • Mitochondrial ATP levels were decreased. • Electron-dense vacuoles were observed in the patients. • Mitochondria from muscle biopsies appeared within normal limits. • One patient did not show these defects possibly due to compensatory mechanisms. - Abstract: Parkinson’s disease (PD), defined as a neurodegenerative disorder, is characterized by the loss of dopaminergic neurons in the substantia nigra in the midbrain. Loss-of-function mutations in the parkin gene are a major cause of autosomal recessive, early-onset PD. Parkin has been implicated in the maintenance of healthy mitochondria, although previous studies show conflicting findings regarding mitochondrial abnormalities in fibroblasts from patients harboring parkin-null mutations. The aim of the present study was to determine whether South African PD patients with parkin mutations exhibit evidence for mitochondrial dysfunction. Fibroblasts were cultured from skin biopsies obtained from three patients with homozygous parkin-null mutations, two heterozygous mutation carriers and two wild-type controls. Muscle biopsies were obtained from two of the patients. The muscle fibers showed subtle abnormalities such as slightly swollen mitochondria in focal areas of the fibers and some folding of the sarcolemma. Although no differences in the degree of mitochondrial network branching were found in the fibroblasts, ultrastructural abnormalities were observed including the presence of electron-dense vacuoles. Moreover, decreased ATP levels which are consistent with mitochondrial dysfunction were observed in the patients’ fibroblasts compared to controls. Remarkably, these defects did not manifest in one patient, which may be due to possible compensatory mechanisms. These results suggest that parkin-null patients exhibit features of mitochondrial dysfunction. Involvement of mitochondria as a key role player in PD

  15. Mitochondrial impairment observed in fibroblasts from South African Parkinson’s disease patients with parkin mutations

    International Nuclear Information System (INIS)

    Merwe, Celia van der; Loos, Ben; Swart, Chrisna; Kinnear, Craig; Henning, Franclo; Merwe, Lize van der; Pillay, Komala; Muller, Nolan; Zaharie, Dan; Engelbrecht, Lize; Carr, Jonathan

    2014-01-01

    Highlights: • Mitochondrial dysfunction observed in patients with parkin-null mutations. • Mitochondrial ATP levels were decreased. • Electron-dense vacuoles were observed in the patients. • Mitochondria from muscle biopsies appeared within normal limits. • One patient did not show these defects possibly due to compensatory mechanisms. - Abstract: Parkinson’s disease (PD), defined as a neurodegenerative disorder, is characterized by the loss of dopaminergic neurons in the substantia nigra in the midbrain. Loss-of-function mutations in the parkin gene are a major cause of autosomal recessive, early-onset PD. Parkin has been implicated in the maintenance of healthy mitochondria, although previous studies show conflicting findings regarding mitochondrial abnormalities in fibroblasts from patients harboring parkin-null mutations. The aim of the present study was to determine whether South African PD patients with parkin mutations exhibit evidence for mitochondrial dysfunction. Fibroblasts were cultured from skin biopsies obtained from three patients with homozygous parkin-null mutations, two heterozygous mutation carriers and two wild-type controls. Muscle biopsies were obtained from two of the patients. The muscle fibers showed subtle abnormalities such as slightly swollen mitochondria in focal areas of the fibers and some folding of the sarcolemma. Although no differences in the degree of mitochondrial network branching were found in the fibroblasts, ultrastructural abnormalities were observed including the presence of electron-dense vacuoles. Moreover, decreased ATP levels which are consistent with mitochondrial dysfunction were observed in the patients’ fibroblasts compared to controls. Remarkably, these defects did not manifest in one patient, which may be due to possible compensatory mechanisms. These results suggest that parkin-null patients exhibit features of mitochondrial dysfunction. Involvement of mitochondria as a key role player in PD

  16. Impaired growth and intracranial calcifications in autosomal dominant hypocalcemia caused by a GNA11 mutation.

    Science.gov (United States)

    Tenhola, Sirpa; Voutilainen, Raimo; Reyes, Monica; Toiviainen-Salo, Sanna; Jüppner, Harald; Mäkitie, Outi

    2016-09-01

    Autosomal dominant hypocalcemia (ADH) is characterized by hypocalcemia and inappropriately low PTH concentrations. ADH type 1 is caused by activating mutations in the calcium-sensing receptor (CASR), a G-protein-coupled receptor signaling through α11 (Gα11) and αq (Gαq) subunits. Heterozygous activating mutations in GNA11, the gene encoding Gα11, underlie ADH type 2. This study describes disease characteristics in a family with ADH caused by a gain-of-function mutation in GNA11. A three-generation family with seven members (3 adults, 4 children) presenting with ADH. Biochemical parameters of calcium metabolism, clinical, genetic and brain imaging findings were analyzed. Sanger sequencing revealed a heterozygous GNA11 missense mutation (c.1018G>A, p.V340M) in all seven hypocalcemic subjects, but not in the healthy family members (n=4). The adult patients showed clinical symptoms of hypocalcemia, while the children were asymptomatic. Plasma ionized calcium ranged from 0.95 to 1.14mmol/L, yet plasma PTH was inappropriately low for the degree of hypocalcemia. Serum 25OHD was normal. Despite hypocalcemia 1,25(OH)2D and urinary calcium excretion were inappropriately in the reference range. None of the patients had nephrocalcinosis. Two adults and one child (of the two MRI scanned children) had distinct intracranial calcifications. All affected subjects had short stature (height s.d. scores ranging from -3.4 to -2.3 vs -0.5 in the unaffected children). The identified GNA11 mutation results in biochemical abnormalities typical for ADH. Additional features, including short stature and early intracranial calcifications, cosegregated with the mutation. These findings may indicate a wider role for Gα11 signaling besides calcium regulation. © 2016 European Society of Endocrinology.

  17. Cognitive impairment in the preclinical stage of dementia in FTD-3 CHMP2B mutation carriers

    DEFF Research Database (Denmark)

    Stokholm, Jette; Teasdale, Thomas W; Johannsen, Peter

    2013-01-01

    -3). Subjects were assessed with neuropsychological tests in 2002, 2005 and 2010. RESULTS: Cross-sectional analyses showed that the mutation carriers scored lower on tests of psychomotor speed, working memory, executive functions and verbal memory than a control group consisting of not-at-risk family...... members and spouses. Longitudinal analyses showed a gradual decline in psychomotor speed, working memory capacity and global executive measures in the group of non-demented mutation carriers that was not found in the control group. In contrast, there were no significant group differences in domain scores...

  18. First de novo ANK3 nonsense mutation in a boy with intellectual disability, speech impairment and autistic features.

    Science.gov (United States)

    Kloth, Katja; Denecke, Jonas; Hempel, Maja; Johannsen, Jessika; Strom, Tim M; Kubisch, Christian; Lessel, Davor

    2017-09-01

    Ankyrin-G, encoded by ANK3, plays an important role in neurodevelopment and neuronal function. There are multiple isoforms of Ankyrin-G resulting in differential tissue expression and function. Heterozygous missense mutations in ANK3 have been associated with autism spectrum disorder. Further, in three siblings a homozygous frameshift mutation affecting only the longest isoform and a patient with a balanced translocation disrupting all isoforms were documented. The latter four patients were affected by a variable degree of intellectual disability, attention deficit hyperactivity disorder and autism. Here, we report on a boy with speech impairment, intellectual disability, autistic features, macrocephaly, macrosomia, chronic hunger and an altered sleeping pattern. By trio-whole-exome sequencing, we identified the first de novo nonsense mutation affecting all ANK3 transcripts. Thus, our data expand the phenotype of ANK3-associated diseases and suggest an isoform-based, phenotypic continuum between dominant and recessive ANK3-associated pathologies. Copyright © 2017. Published by Elsevier Masson SAS.

  19. Homozygous SLC6A17 Mutations Cause Autosomal-Recessive Intellectual Disability with Progressive Tremor, Speech Impairment, and Behavioral Problems

    Science.gov (United States)

    Iqbal, Zafar; Willemsen, Marjolein H.; Papon, Marie-Amélie; Musante, Luciana; Benevento, Marco; Hu, Hao; Venselaar, Hanka; Wissink-Lindhout, Willemijn M.; Vulto-van Silfhout, Anneke T.; Vissers, Lisenka E.L.M.; de Brouwer, Arjan P.M.; Marouillat, Sylviane; Wienker, Thomas F.; Ropers, Hans Hilger; Kahrizi, Kimia; Nadif Kasri, Nael; Najmabadi, Hossein; Laumonnier, Frédéric; Kleefstra, Tjitske; van Bokhoven, Hans

    2015-01-01

    We report on Dutch and Iranian families with affected individuals who present with moderate to severe intellectual disability and additional phenotypes including progressive tremor, speech impairment, and behavioral problems in certain individuals. A combination of exome sequencing and homozygosity mapping revealed homozygous mutations c.484G>A (p.Gly162Arg) and c.1898C>G (p.Pro633Arg) in SLC6A17. SLC6A17 is predominantly expressed in the brain, encodes a synaptic vesicular transporter of neutral amino acids and glutamate, and plays an important role in the regulation of glutamatergic synapses. Prediction programs and 3D modeling suggest that the identified mutations are deleterious to protein function. To directly test the functional consequences, we investigated the neuronal subcellular localization of overexpressed wild-type and mutant variants in mouse primary hippocampal neuronal cells. Wild-type protein was present in soma, axons, dendrites, and dendritic spines. p.Pro633Arg altered SLC6A17 was found in soma and proximal dendrites but did not reach spines. p.Gly162Arg altered SLC6A17 showed a normal subcellular distribution but was associated with an abnormal neuronal morphology mainly characterized by the loss of dendritic spines. In summary, our genetic findings implicate homozygous SLC6A17 mutations in autosomal-recessive intellectual disability, and their pathogenic role is strengthened by genetic evidence and in silico and in vitro functional analyses. PMID:25704603

  20. Opinions of hearing parents about the causes of hearing impairment of their children with biallelic GJB2 mutations.

    Science.gov (United States)

    Solovyev, Aisen V; Dzhemileva, Lilya U; Posukh, Olga L; Barashkov, Nikolay A; Bady-Khoo, Marita S; Lobov, Semen L; Popova, Natalya Yu; Romanov, Georgii P; Sazonov, Nikolay N; Bondar, Alexander A; Morozov, Igor V; Tomsky, Mikhail I; Fedorova, Sardana A; Khusnutdinova, Elza K

    2017-07-01

    Hereditary hearing impairment (HI) caused by recessive GJB2 mutations is a frequent sensory disorder. The results of the molecular-based studies of HI are widely used in various genetic test systems. However, the ethical aspects are less described than the genetic aspects. The concerns expressed by individuals from groups with genetic risks must be included in the counseling of patients and their families. For evaluation of subjective opinions of hearing parents about the presumed causes of HI of their children, we analyze the cohort of parents having children with confirmed hereditary HI caused by biallelic recessive GJB2 mutations (in a homozygous or a compound heterozygous state). This study included 70 deaf children with HI due to mutations in the GJB2 gene and 91 questionnaires about the presumed causes of their deafness filled by their parents. Most of the parents at 78% (CI 68.4-85.4%) attributed their children's HI to "non-hereditary" causes and 22% (CI 14.7-31.6%) to "hereditary" causes (p < 0.05). Therefore, the prior opinions of the parents did not correspond to positive GJB2 genetic testing results. The subjective opinions of parents are probably partly based on family history, since respondents with deaf relatives in their pedigree more likely supposed hereditary causes for HI in their children than the respondents without deaf relatives (p < 0.001).

  1. Association of Early-Onset Spasticity and Risk for Cognitive Impairment With Mutations at Amino Acid 499 in SPAST.

    Science.gov (United States)

    Gillespie, Meredith K; Humphreys, Peter; McMillan, Hugh J; Boycott, Kym M

    2018-04-01

    Hereditary spastic paraplegia is a phenotypically and genetically heterogeneous group of neurodegenerative disorders characterized by lower extremity weakness and spasticity. Spastic paraplegia 4 (SPG4), caused by heterozygous mutations in the gene SPAST, typically causes a late-onset, uncomplicated form of hereditary spastic paraplegia in affected individuals. Additional clinical features in SPG4 have been reported on occasion, but no genotype-phenotype correlation has been established. Through targeted clinical testing, we identified 2 unrelated female patients with the same de novo p.Arg499His mutation in SPAST. Both patients presented with early-onset spasticity resulting in delayed motor milestones, which led to a diagnosis of cerebral palsy in one child and tethered cord in the other. Review of the literature identified several patients with mutations at amino acid 499 and early-onset symptoms associated with a risk of cognitive impairment. Early and accurate diagnosis of children with early-onset spasticity is important for informed prognosis and genetic counselling.

  2. A deleterious Nav1.1 mutation selectively impairs telencephalic inhibitory neurons derived from Dravet Syndrome patients

    Science.gov (United States)

    Sun, Yishan; Paşca, Sergiu P; Portmann, Thomas; Goold, Carleton; Worringer, Kathleen A; Guan, Wendy; Chan, Karen C; Gai, Hui; Vogt, Daniel; Chen, Ying-Jiun J; Mao, Rong; Chan, Karrie; Rubenstein, John LR; Madison, Daniel V; Hallmayer, Joachim; Froehlich-Santino, Wendy M; Bernstein, Jonathan A; Dolmetsch, Ricardo E

    2016-01-01

    Dravet Syndrome is an intractable form of childhood epilepsy associated with deleterious mutations in SCN1A, the gene encoding neuronal sodium channel Nav1.1. Earlier studies using human induced pluripotent stem cells (iPSCs) have produced mixed results regarding the importance of Nav1.1 in human inhibitory versus excitatory neurons. We studied a Nav1.1 mutation (p.S1328P) identified in a pair of twins with Dravet Syndrome and generated iPSC-derived neurons from these patients. Characterization of the mutant channel revealed a decrease in current amplitude and hypersensitivity to steady-state inactivation. We then differentiated Dravet-Syndrome and control iPSCs into telencephalic excitatory neurons or medial ganglionic eminence (MGE)-like inhibitory neurons. Dravet inhibitory neurons showed deficits in sodium currents and action potential firing, which were rescued by a Nav1.1 transgene, whereas Dravet excitatory neurons were normal. Our study identifies biophysical impairments underlying a deleterious Nav1.1 mutation and supports the hypothesis that Dravet Syndrome arises from defective inhibitory neurons. DOI: http://dx.doi.org/10.7554/eLife.13073.001 PMID:27458797

  3. Spinal muscular atrophy pathogenic mutations impair the axonogenic properties of axonal-survival of motor neuron.

    Science.gov (United States)

    Locatelli, Denise; d'Errico, Paolo; Capra, Silvia; Finardi, Adele; Colciaghi, Francesca; Setola, Veronica; Terao, Mineko; Garattini, Enrico; Battaglia, Giorgio

    2012-05-01

    The axonal survival of motor neuron (a-SMN) protein is a truncated isoform of SMN1, the spinal muscular atrophy (SMA) disease gene. a-SMN is selectively localized in axons and endowed with remarkable axonogenic properties. At present, the role of a-SMN in SMA is unknown. As a first step to verify a link between a-SMN and SMA, we investigated by means of over-expression experiments in neuroblastoma-spinal cord hybrid cell line (NSC34) whether SMA pathogenic mutations located in the N-terminal part of the protein affected a-SMN function. We demonstrated here that either SMN1 missense mutations or small intragenic re-arrangements located in the Tudor domain consistently altered the a-SMN capability of inducing axonal elongation in vitro. Mutated human a-SMN proteins determined in almost all NSC34 motor neurons the growth of short axons with prominent morphologic abnormalities. Our data indicate that the Tudor domain is critical in dictating a-SMN function possibly because it is an association domain for proteins involved in axon growth. They also indicate that Tudor domain mutations are functionally relevant not only for FL-SMN but also for a-SMN, raising the possibility that also a-SMN loss of function may contribute to the pathogenic steps leading to SMA. © 2012 The Authors. Journal of Neurochemistry © 2012 International Society for Neurochemistry.

  4. Functional characterization of the protein C A267T mutation: evidence for impaired secretion due to defective intracellular transport

    Directory of Open Access Journals (Sweden)

    Tjeldhorn Lena

    2010-09-01

    Full Text Available Abstract Background Activated protein C (PC is a serine protease that regulates blood coagulation by inactivating coagulation factors Va and VIIIa. PC deficiency is an autosomally inherited disorder associated with a high risk of recurrent venous thrombosis. The aim of the study was to explore the mechanisms responsible for severe PC deficiency in a patient with the protein C A267T mutation by in-vitro expression studies. Results Huh7 and CHO-K1 cells were transiently transfected with expression vectors containing wild-type (WT PC and mutated PC (A267T PC cDNAs. PC mRNA levels were assessed by qRT-PCR and the PC protein levels were measured by ELISA. The mRNA levels of WT PC and A267T PC were similar, while the intracellular protein level of A267T PC was moderately decreased compared to WT PC. The secretion of A267T PC into the medium was severely impaired. No differences in molecular weights were observed between WT and A267T PC before and after treatment with endo-β-N-acetylglucosaminidase. Proteasomal and lysosomal degradations were examined using lactacystin and bafilomycin, respectively, and revealed that A267T PC was slightly more susceptible for proteasomal degradation than WT PC. Intracellular co-localization analysis indicated that A267T PC was mainly located in the endoplasmic reticulum (ER, whereas WT PC was observed in both ER and Golgi. Conclusions In contrast to what has been reported for other PC mutants, intracellular degradation of A267T PC was not the main/dominant mechanism underlying the reduced intracellular and secretion levels of PC. Our results indicate that the A267T mutation most likely caused misfolding of PC, which might lead to increased retention of the mutated PC in ER.

  5. Production of infectious genotype 1b virus particles in cell culture and impairment by replication enhancing mutations.

    Directory of Open Access Journals (Sweden)

    Thomas Pietschmann

    2009-06-01

    Full Text Available With the advent of subgenomic hepatitis C virus (HCV replicons, studies of the intracellular steps of the viral replication cycle became possible. These RNAs are capable of self-amplification in cultured human hepatoma cells, but save for the genotype 2a isolate JFH-1, efficient replication of these HCV RNAs requires replication enhancing mutations (REMs, previously also called cell culture adaptive mutations. These mutations cluster primarily in the central region of non-structural protein 5A (NS5A, but may also reside in the NS3 helicase domain or at a distinct position in NS4B. Most efficient replication has been achieved by combining REMs residing in NS3 with distinct REMs located in NS4B or NS5A. However, in spite of efficient replication of HCV genomes containing such mutations, they do not support production of infectious virus particles. By using the genotype 1b isolate Con1, in this study we show that REMs interfere with HCV assembly. Strongest impairment of virus formation was found with REMs located in the NS3 helicase (E1202G and T1280I as well as NS5A (S2204R, whereas a highly adaptive REM in NS4B still allowed virus production although relative levels of core release were also reduced. We also show that cells transfected with the Con1 wild type genome or the genome containing the REM in NS4B release HCV particles that are infectious both in cell culture and in vivo. Our data provide an explanation for the in vitro and in vivo attenuation of cell culture adapted HCV genomes and may open new avenues for the development of fully competent culture systems covering the therapeutically most relevant HCV genotypes.

  6. Spastic paraplegia and OXPHOS impairment caused by mutations in paraplegin, a nuclear-encoded mitochondrial metalloprotease.

    Science.gov (United States)

    Casari, G; De Fusco, M; Ciarmatori, S; Zeviani, M; Mora, M; Fernandez, P; De Michele, G; Filla, A; Cocozza, S; Marconi, R; Dürr, A; Fontaine, B; Ballabio, A

    1998-06-12

    Hereditary spastic paraplegia (HSP) is characterized by progressive weakness and spasticity of the lower limbs due to degeneration of corticospinal axons. We found that patients from a chromosome 16q24.3-linked HSP family are homozygous for a 9.5 kb deletion involving a gene encoding a novel protein, named Paraplegin. Two additional Paraplegin mutations, both resulting in a frameshift, were found in a complicated and in a pure form of HSP. Paraplegin is highly homologous to the yeast mitochondrial ATPases, AFG3, RCA1, and YME1, which have both proteolytic and chaperon-like activities at the inner mitochondrial membrane. Immunofluorescence analysis and import experiments showed that Paraplegin localizes to mitochondria. Analysis of muscle biopsies from two patients carrying Paraplegin mutations showed typical signs of mitochondrial OXPHOS defects, thus suggesting a mechanism for neurodegeneration in HSP-type disorders.

  7. Axonal Transport of TDP-43 mRNA Granules Is Impaired by ALS-Causing Mutations

    OpenAIRE

    Alami, Nael H.; Smith, Rebecca B.; Carrasco, Monica A.; Williams, Luis A.; Winborn, Christina S.; Han, Steve S.W.; Kiskinis, Evangelos; Winborn, Brett; Freibaum, Brian D.; Kanagaraj, Anderson; Clare, Alison J.; Badders, Nisha M.; Bilican, Bilada; Chaum, Edward; Chandran, Siddharthan

    2014-01-01

    The RNA binding protein TDP-43 regulates RNA metabolism at multiple levels, including transcription, RNA splicing, and mRNA stability. TDP-43 is a major component of the cytoplasmic inclusions characteristic of amyotrophic lateral sclerosis and some types of frontotemporal lobar degeneration. The importance of TDP-43 in disease is underscored by the fact that dominant missense mutations are sufficient to cause disease, although the role of TDP-43 in pathogenesis is unknown. ...

  8. Mutations in Alström Protein Impair Terminal Differentiation of Cardiomyocytes

    OpenAIRE

    Shenje, Lincoln T.; Andersen, Peter; Halushka, Marc K.; Lui, Cecillia; Fernandez, Laviel; Collin, Gayle B.; Amat-Alarcon, Nuria; Meschino, Wendy; Cutz, Ernest; Chang, Kenneth; Yonescu, Raluca; Batista, Denise A. S.; Chen, Yan; Chelko, Stephen; Crosson, Jane E.

    2014-01-01

    Cardiomyocyte cell division and replication in mammals proceed through embryonic development and abruptly decline soon after birth. The process governing cardiomyocyte cell cycle arrest is poorly understood. Here we carry out whole exome sequencing in an infant with evidence of persistent postnatal cardiomyocyte replication to determine the genetic risk factors. We identify compound heterozygous ALMS1 mutations in the proband, and confirm their presence in her affected sibling, one copy inher...

  9. Mutations in OTOF, CLDN14 & SLC26A4 genes as major causes of hearing impairment in Dhadkai village, Jammu & Kashmir, India

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    Nishtha Pandey

    2017-01-01

    Interpretation & conclusions: This study suggested considerable genetic heterogeneity in the causation of hearing loss in Dhadkai. Recessive mutations were observed in at least three genes causing hearing loss: OTOF (p.R708X, SLC26A4 (p.Y556X and CLDN14 (p.V85D. Mutation p.R708X appeared to be the major cause of hearing impairment in Dhadkai.

  10. Juvenile-onset Sporadic Amyotrophic Lateral Sclerosis with a Frameshift FUS Gene Mutation Presenting Unique Neuroradiological Findings and Cognitive Impairment.

    Science.gov (United States)

    Hirayanagi, Kimitoshi; Sato, Masayuki; Furuta, Natsumi; Makioka, Kouki; Ikeda, Yoshio

    2016-01-01

    A 24-year-old Japanese woman developed anterocollis, weakness of the proximal arms, and subsequent cognitive impairment. A neurological examination revealed amyotrophic lateral sclerosis (ALS) without a family history. Systemic muscle atrophy progressed rapidly. Cerebral MRI clearly exhibited high signal intensities along the bilateral pyramidal tracts. An analysis of the FUS gene revealed a heterozygous two-base pair deletion, c.1507-1508delAG (p.G504WfsX515). A subset of juvenile-onset familial/sporadic ALS cases with FUS gene mutations reportedly demonstrates mental retardation or learning difficulty. Our study emphasizes the importance of conducting a FUS gene analysis in juvenile-onset ALS cases, even when no family occurrence is confirmed.

  11. Homozygous SLC6A17 mutations cause autosomal-recessive intellectual disability with progressive tremor, speech impairment, and behavioral problems.

    Science.gov (United States)

    Iqbal, Zafar; Willemsen, Marjolein H; Papon, Marie-Amélie; Musante, Luciana; Benevento, Marco; Hu, Hao; Venselaar, Hanka; Wissink-Lindhout, Willemijn M; Vulto-van Silfhout, Anneke T; Vissers, Lisenka E L M; de Brouwer, Arjan P M; Marouillat, Sylviane; Wienker, Thomas F; Ropers, Hans Hilger; Kahrizi, Kimia; Nadif Kasri, Nael; Najmabadi, Hossein; Laumonnier, Frédéric; Kleefstra, Tjitske; van Bokhoven, Hans

    2015-03-05

    We report on Dutch and Iranian families with affected individuals who present with moderate to severe intellectual disability and additional phenotypes including progressive tremor, speech impairment, and behavioral problems in certain individuals. A combination of exome sequencing and homozygosity mapping revealed homozygous mutations c.484G>A (p.Gly162Arg) and c.1898C>G (p.Pro633Arg) in SLC6A17. SLC6A17 is predominantly expressed in the brain, encodes a synaptic vesicular transporter of neutral amino acids and glutamate, and plays an important role in the regulation of glutamatergic synapses. Prediction programs and 3D modeling suggest that the identified mutations are deleterious to protein function. To directly test the functional consequences, we investigated the neuronal subcellular localization of overexpressed wild-type and mutant variants in mouse primary hippocampal neuronal cells. Wild-type protein was present in soma, axons, dendrites, and dendritic spines. p.Pro633Arg altered SLC6A17 was found in soma and proximal dendrites but did not reach spines. p.Gly162Arg altered SLC6A17 showed a normal subcellular distribution but was associated with an abnormal neuronal morphology mainly characterized by the loss of dendritic spines. In summary, our genetic findings implicate homozygous SLC6A17 mutations in autosomal-recessive intellectual disability, and their pathogenic role is strengthened by genetic evidence and in silico and in vitro functional analyses. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  12. Tyr120Asp mutation alters domain flexibility and dynamics of MeCP2 DNA binding domain leading to impaired DNA interaction: Atomistic characterization of a Rett syndrome causing mutation.

    Science.gov (United States)

    D'Annessa, Ilda; Gandaglia, Anna; Brivio, Elena; Stefanelli, Gilda; Frasca, Angelisa; Landsberger, Nicoletta; Di Marino, Daniele

    2018-05-01

    Mutations in the X-linked MECP2 gene represent the main origin of Rett syndrome, causing a profound intellectual disability in females. MeCP2 is an epigenetic transcriptional regulator containing two main functional domains: a methyl-CpG binding domain (MBD) and a transcription repression domain (TRD). Over 600 pathogenic mutations were reported to affect the whole protein; almost half of missense mutations affect the MBD. Understanding the impact of these mutations on the MBD structure and interaction with DNA will foster the comprehension of their pathogenicity and possibly genotype/phenotype correlation studies. Herein, we use molecular dynamics simulations to obtain a detailed view of the dynamics of WT and mutated MBD in the presence and absence of DNA. The pathogenic mutation Y120D is used as paradigm for our studies. Further, since the Y120 residue was previously found to be a phosphorylation site, we characterize the dynamic profile of the MBD also in the presence of Y120 phosphorylation (pY120). We found that addition of a phosphate group to Y120 or mutation in aspartic acid affect domain mobility that samples an alternative conformational space with respect to the WT, leading to impaired ability to interact with DNA. Experimental assays showing a significant reduction in the binding affinity between the mutated MBD and the DNA confirmed our predictions. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. GJB2 (Connexin-26) mutations are not frequent among hearing impaired patients in East Greenland

    DEFF Research Database (Denmark)

    Homoe, P.; Koch, A.; Rendtorff, Nanna Dahl

    2012-01-01

    Objective: Investigate genetic causes of HI among the Inuit populations in the Arctic with a high prevalence of hearing impairment (HI). Design: A cross-sectional survey with population-based controls. Study sample: Forty-five patients, with sensorineural or mixed HI and an available blood sample...... for GJB2 sequencing from DNA, were selected from 166 East Greenlanders by specialist audiology examination, including pure-tone air and bone conduction audiometry from 125 Hz to 8000 Hz. Controls were 108 East- and 109 West-Greenlanders. Results: Forty-five patients with HI were included, 24 males and 21...

  14. Human surfactant protein A2 gene mutations impair dimmer/trimer assembly leading to deficiency in protein sialylation and secretion.

    Directory of Open Access Journals (Sweden)

    Yi Song

    Full Text Available Surfactant protein A2 (SP-A2 plays an essential role in surfactant metabolism and lung host defense. SP-A2 mutations in the carbohydrate recognition domain have been related to familial pulmonary fibrosis and can lead to a recombinant protein secretion deficiency in vitro. In this study, we explored the molecular mechanism of protein secretion deficiency and the subsequent biological effects in CHO-K1 cells expressing both wild-type and several different mutant forms of SP-A2. We demonstrate that the SP-A2 G231V and F198S mutants impair the formation of dimmer/trimer SP-A2 which contributes to the protein secretion defect. A deficiency in sialylation, but not N-linked glycosylation, is critical to the observed dimmer/trimer impairment-induced secretion defect. Furthermore, both mutant forms accumulate in the ER and form NP-40-insoluble aggregates. In addition, the soluble mutant SP-A2 could be partially degraded through the proteasome pathway but not the lysosome or autophagy pathway. Intriguingly, 4-phenylbutyrate acid (4-PBA, a chemical chaperone, alleviates aggregate formation and partially rescued the protein secretion of SP-A2 mutants. In conclusion, SP-A2 G231V and F198S mutants impair the dimmer/trimer assembly, which contributes to the protein sialylation and secretion deficiency. The intracellular protein mutants could be partially degraded through the proteasome pathway and also formed aggregates. The treatment of the cells with 4-PBA resulted in reduced aggregation and rescued the secretion of mutant SP-A2.

  15. A combination of two truncating mutations in USH2A causes more severe and progressive hearing impairment in Usher syndrome type IIa

    NARCIS (Netherlands)

    Hartel, B.P.; Lofgren, M.; Huygen, P.L.; Guchelaar, I.; Lo, A.N.K.N.; Sadeghi, A.M.; van Wijk, E.; Tranebjaerg, L.; Kremer, H.; Kimberling, W.J.; Cremers, C.W.R.J.; Moller, C.; Pennings, R.J.

    2016-01-01

    OBJECTIVES: Usher syndrome is an inherited disorder that is characterized by hearing impairment (HI), retinitis pigmentosa, and in some cases vestibular dysfunction. Usher syndrome type IIa is caused by mutations in USH2A. HI in these patients is highly heterogeneous and the present study evaluates

  16. COPA mutations impair ER-Golgi transport causing hereditary autoimmune-mediated lung disease and arthritis

    Science.gov (United States)

    Watkin, Levi B.; Jessen, Birthe; Wiszniewski, Wojciech; Vece, Timothy; Jan, Max; Sha, Youbao; Thamsen, Maike; Santos-Cortez, Regie L. P.; Lee, Kwanghyuk; Gambin, Tomasz; Forbes, Lisa; Law, Christopher S.; Stray-Petersen, Asbjørg; Cheng, Mickie H.; Mace, Emily M.; Anderson, Mark S.; Liu, Dongfang; Tang, Ling Fung; Nicholas, Sarah K.; Nahmod, Karen; Makedonas, George; Canter, Debra; Kwok, Pui-Yan; Hicks, John; Jones, Kirk D.; Penney, Samantha; Jhangiani, Shalini N.; Rosenblum, Michael D.; Dell, Sharon D.; Waterfield, Michael R.; Papa, Feroz R.; Muzny, Donna M.; Zaitlen, Noah; Leal, Suzanne M.; Gonzaga-Jauregui, Claudia; Boerwinkle, Eric; Eissa, N. Tony; Gibbs, Richard A.; Lupski, James R.; Orange, Jordan S.; Shum, Anthony K.

    2015-01-01

    Advances in genomics have allowed unbiased genetic studies of human disease with unexpected insights into the molecular mechanisms of cellular immunity and autoimmunity1. We performed whole exome sequencing (WES) and targeted sequencing in patients with an apparent Mendelian syndrome of autoimmune disease characterized by high-titer autoantibodies, inflammatory arthritis and interstitial lung disease (ILD). In five families, we identified four unique deleterious variants in the Coatomer subunit alpha (COPA) gene all located within the same functional domain. We hypothesized that mutant COPA leads to a defect in intracellular transport mediated by coat protein complex I (COPI)2–4. We show that COPA variants impair binding of proteins targeted for retrograde Golgi to ER transport and demonstrate that expression of mutant COPA leads to ER stress and the upregulation of Th17 priming cytokines. Consistent with this pattern of cytokine expression, patients demonstrated a significant skewing of CD4+ T cells toward a T helper 17 (Th17) phenotype, an effector T cell population implicated in autoimmunity5,6. Our findings uncover an unexpected molecular link between a vesicular transport protein and a syndrome of autoimmunity manifested by lung and joint disease. These findings provide a unique opportunity to understand how alterations in cellular homeostasis caused by a defect in the intracellular trafficking pathway leads to the generation of human autoimmune disease. PMID:25894502

  17. A mutation in the glutamate-rich region of RNA-binding motif protein 20 causes dilated cardiomyopathy through missplicing of titin and impaired Frank-Starling mechanism

    DEFF Research Database (Denmark)

    Beqqali, Abdelaziz; Bollen, I. A. E.; Rasmussen, T. B.

    2016-01-01

    Mutations in the RS-domain of RNA-binding motif protein 20 (RBM20) have recently been identified to segregate with aggressive forms of familial dilated cardiomyopathy (DCM). Loss of RBM20 in rats results in missplicing of the sarcomeric gene titin (TTN). The functional and physiological consequen......Mutations in the RS-domain of RNA-binding motif protein 20 (RBM20) have recently been identified to segregate with aggressive forms of familial dilated cardiomyopathy (DCM). Loss of RBM20 in rats results in missplicing of the sarcomeric gene titin (TTN). The functional and physiological...... consequences of RBM20 mutations outside the mutational hotspot of RBM20 have not been explored to date. In this study, we investigated the pathomechanism of DCM caused by a novel RBM20 mutation in human cardiomyocytes. We identified a family with DCM carrying a mutation (RBM20(E913K/+)) in a glutamate...... to the early onset, and malignant course of DCM caused by RBM20 mutations. Altogether, our results demonstrate that heterozygous loss of RBM20 suffices to profoundly impair myocyte biomechanics by its disturbance of TTN splicing....

  18. Mutation in rod PDE6 linked to congenital stationary night blindness impairs the enzyme inhibition by its gamma-subunit.

    Science.gov (United States)

    Muradov, Khakim G; Granovsky, Alexey E; Artemyev, Nikolai O

    2003-03-25

    Photoreceptor cGMP phosphodiesterase (PDE6) is the effector enzyme in the vertebrate visual transduction cascade. The activity of rod PDE6 catalytic alpha- and beta-subunits is blocked in the dark by two inhibitory Pgamma-subunits. The inhibition is released upon light-stimulation of photoreceptor cells. Mutation H258N in PDE6beta has been linked to congenital stationary night blindness (CSNB) in a large Danish family (Rambusch pedigree) (Gal, A., Orth, U., Baehr, W., Schwinger, E., and Rosenberg, T. (1994) Nat. Genet. 7, 64-67.) We have analyzed the consequences of this mutation for PDE6 function using a Pgamma-sensitive PDE6alpha'/PDE5 chimera, Chi16. Biochemical analysis of the H257N mutant, an equivalent of PDE6betaH258N, demonstrates that this substitution does not alter the ability of chimeric PDE to dimerize or the enzyme's catalytic properties. The sensitivity of H257N to a competitive inhibitor zaprinast was also unaffected. However, the mutant displayed a significant impairment in the inhibitory interaction with Pgamma, which was apparent from a approximately 20-fold increase in the K(i) value (46 nM) and incomplete maximal inhibition. The inhibitory defect of H257N is not due to perturbation of noncatalytic cGMP binding to the PDE6alpha' GAF domains. The noncatalytic cGMP-binding characteristics of the H257N mutant were similar to those of the parent PDE6alpha'/PDE5 chimera. Since rod PDE6 in the Rambusch CSNB is a catalytic heterodimer of the wild-type PDE6alpha and mutant PDE6beta, Chi16 and H257N were coexpressed, and a heterodimeric PDE, Chi16/H257N, was isolated. It displayed two Pgamma inhibitory sites with the K(i) values of 5 and 57 nM. Our results support the hypothesis that mutation H258N in PDE6beta causes CSNB through incomplete inhibition of PDE6 activity by Pgamma, which leads to desensitization of rod photoreceptors.

  19. A Novel Mutation in Isoform 3 of the Plasma Membrane Ca2+ Pump Impairs Cellular Ca2+ Homeostasis in a Patient with Cerebellar Ataxia and Laminin Subunit 1α Mutations.

    Science.gov (United States)

    Calì, Tito; Lopreiato, Raffaele; Shimony, Joshua; Vineyard, Marisa; Frizzarin, Martina; Zanni, Ginevra; Zanotti, Giuseppe; Brini, Marisa; Shinawi, Marwan; Carafoli, Ernesto

    2015-06-26

    The particular importance of Ca(2+) signaling to neurons demands its precise regulation within their cytoplasm. Isoform 3 of the plasma membrane Ca(2+) ATPase (the PMCA3 pump), which is highly expressed in brain and cerebellum, plays an important role in the regulation of neuronal Ca(2+). A genetic defect of the PMCA3 pump has been described in one family with X-linked congenital cerebellar ataxia. Here we describe a novel mutation in the ATP2B3 gene in a patient with global developmental delay, generalized hypotonia and cerebellar ataxia. The mutation (a R482H replacement) impairs the Ca(2+) ejection function of the pump. It reduces the ability of the pump expressed in model cells to control Ca(2+) transients generated by cell stimulation and impairs its Ca(2+) extrusion function under conditions of low resting cytosolic Ca(2+) as well. In silico analysis of the structural effect of the mutation suggests a reduced stabilization of the portion of the pump surrounding the mutated residue in the Ca(2+)-bound state. The patient also carries two missense mutations in LAMA1, encoding laminin subunit 1α. On the basis of the family pedigree of the patient, the presence of both PMCA3 and laminin subunit 1α mutations appears to be necessary for the development of the disease. Considering the observed defect in cellular Ca(2+) homeostasis and the previous finding that PMCAs act as digenic modulators in Ca(2+)-linked pathologies, the PMCA3 dysfunction along with LAMA1 mutations could act synergistically to cause the neurological phenotype. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. A Novel Mutation in Isoform 3 of the Plasma Membrane Ca2+ Pump Impairs Cellular Ca2+ Homeostasis in a Patient with Cerebellar Ataxia and Laminin Subunit 1α Mutations*

    Science.gov (United States)

    Calì, Tito; Lopreiato, Raffaele; Shimony, Joshua; Vineyard, Marisa; Frizzarin, Martina; Zanni, Ginevra; Zanotti, Giuseppe; Brini, Marisa; Shinawi, Marwan; Carafoli, Ernesto

    2015-01-01

    The particular importance of Ca2+ signaling to neurons demands its precise regulation within their cytoplasm. Isoform 3 of the plasma membrane Ca2+ ATPase (the PMCA3 pump), which is highly expressed in brain and cerebellum, plays an important role in the regulation of neuronal Ca2+. A genetic defect of the PMCA3 pump has been described in one family with X-linked congenital cerebellar ataxia. Here we describe a novel mutation in the ATP2B3 gene in a patient with global developmental delay, generalized hypotonia and cerebellar ataxia. The mutation (a R482H replacement) impairs the Ca2+ ejection function of the pump. It reduces the ability of the pump expressed in model cells to control Ca2+ transients generated by cell stimulation and impairs its Ca2+ extrusion function under conditions of low resting cytosolic Ca2+ as well. In silico analysis of the structural effect of the mutation suggests a reduced stabilization of the portion of the pump surrounding the mutated residue in the Ca2+-bound state. The patient also carries two missense mutations in LAMA1, encoding laminin subunit 1α. On the basis of the family pedigree of the patient, the presence of both PMCA3 and laminin subunit 1α mutations appears to be necessary for the development of the disease. Considering the observed defect in cellular Ca2+ homeostasis and the previous finding that PMCAs act as digenic modulators in Ca2+-linked pathologies, the PMCA3 dysfunction along with LAMA1 mutations could act synergistically to cause the neurological phenotype. PMID:25953895

  1. Identification of a Novel TECTA mutation in a Chinese DFNA8/12 family with prelingual progressive sensorineural hearing impairment.

    Directory of Open Access Journals (Sweden)

    Zhengyue Li

    Full Text Available Tectorial membrane, an extracellular matrix of the cochlea, plays a crucial role in the transmission of sound to the sensory hair cells. Alpha-tectorin is the most important noncollagenous component of the tectorial membrane and the otolith membrane in the maculae of the vestibular system. Defects in TECTA, the gene encodes alpha-tectorin, are cause of both dominant (DFNA8/12 and recessive (DFNB21 forms of deafness. Here, we report a three-generation Chinese family characterized by prelingual progressive sensorineural hearing impairment. We mapped the disease locus to chromosome 11q23-24 region, overlapping with the DFNA8/12 locus. Sequencing of candidate gene TECTA revealed a heterozygous c.5945C>A substitution in exon 19, causing amino acid substitution of Ala to Asp at a conservative position 1982. The A1982D substitution is consistent with hearing loss in this Chinese family and has not been found in 200 random control chromosomes. To our knowledge, this is the first TECTA mutation identified in Chinese population. Our data provides additional molecular and clinical information for establishing a better genotype-phenotype understanding of DFNA8/12.

  2. Association of HFE common mutations with Parkinson's disease, Alzheimer's disease and mild cognitive impairment in a Portuguese cohort

    Directory of Open Access Journals (Sweden)

    Morgadinho Ana S

    2006-07-01

    Full Text Available Abstract Background Pathological brain iron deposition has been implicated as a source of neurotoxic reactive oxygen species in Alzheimer (AD and Parkinson diseases (PD. Iron metabolism is associated with the gene hemochromatosis (HFE Human genome nomenclature committee ID:4886, and mutations in HFE are a cause of the iron mismetabolism disease, hemochromatosis. Several reports have tested the association of HFE variants with neurodegenerative diseases, such as AD and PD with conflicting results. Methods Genotypes were analysed for the two most common variants of HFE in a series of 130 AD, 55 Mild Cognitive Impairment (MCI and 132 PD patients. Additionally, a series of 115 healthy age-matched controls was also screened. Results A statistically significant association was found in the PD group when compared to controls, showing that the presence of the C282Y variant allele may confer higher risk for developing the disease. Conclusion Taken together these results suggest that the common variants in HFE may be a risk factor for PD, but not for AD in the Portuguese population.

  3. Mitochondrial Dysfunction Contributes to Impaired Insulin Secretion in INS-1 Cells with Dominant-negative Mutations of HNF-1α and in HNF-1α-deficient Islets*

    OpenAIRE

    Pongratz, Rebecca L.; Kibbey, Richard G.; Kirkpatrick, Clare L.; Zhao, Xiaojian; Pontoglio, Marco; Yaniv, Moshe; Wollheim, Claes B.; Shulman, Gerald I.; Cline, Gary W.

    2009-01-01

    Maturity Onset Diabetes of the Young-type 3 (MODY-3) has been linked to mutations in the transcription factor hepatic nuclear factor (HNF)-1α, resulting in deficiency in glucose-stimulated insulin secretion. In INS-1 cells overexpressing doxycycline-inducible HNF-1α dominant-negative (DN-) gene mutations, and islets from Hnf-1α knock-out mice, insulin secretion was impaired in response to glucose (15 mm) and other nutrient secretagogues. Decreased rates of insulin secretion in response to glu...

  4. Identification of a novel homozygous mutation in MYO3A in a Chinese family with DFNB30 non-syndromic hearing impairment.

    Science.gov (United States)

    Qu, Ronggui; Sang, Qing; Xu, Yao; Feng, Ruizhi; Jin, Li; He, Lin; Wang, Lei

    2016-05-01

    Hearing loss is a common sensory impairment. Several genetic loci or genes responsible for non-syndrome hearing loss have been identified, including the well-known deafness genes GJB2, MT-RNR1 and SLC26A4. MYO3A belongs to the myosin superfamily. Previously only three mutations in this gene have been found in an Isreali family with DFNB30, in which patients demonstrated progressive hearing loss. In this study, we characterized a consanguineous Kazakh family with congenital hearing loss. By targeted sequence capture and next-generation sequencing, we identified a homozygous mutation and did bioinformatics analysis to this mutation. A homozygous mutation, MYO3A:c.1841C>T (p.S614F), was identified to be responsible for the disease. Ser614 is located in the motor domain of MYO3A that is highly conserved among different species. Molecular modeling predicts that the conserved Ser614 may play an important role in maintaining the stability of β-sheet and the interaction between neighboring β-strand. This is the second report on MYO3A mutations in deafness and the first report in China. The finding help facilitate establishing a better relationship between MYO3A mutation and hearing phenotypes. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Pathogenic mutations of the human mitochondrial citrate carrier SLC25A1 lead to impaired citrate export required for lipid, dolichol, ubiquinone and sterol synthesis.

    Science.gov (United States)

    Majd, Homa; King, Martin S; Smith, Anthony C; Kunji, Edmund R S

    2018-01-01

    Missense mutations of the human mitochondrial citrate carrier, encoded by the SLC25A1 gene, lead to an autosomal recessive neurometabolic disorder characterised by neonatal-onset encephalopathy with severe muscular weakness, intractable seizures, respiratory distress, and lack of psychomotor development, often resulting in early death. Here, we have measured the effect of all twelve known pathogenic mutations on the transport activity. The results show that nine mutations abolish transport of citrate completely, whereas the other three reduce the transport rate by >70%, indicating that impaired citrate transport is the most likely primary cause of the disease. Some mutations may be detrimental to the structure of the carrier, whereas others may impair key functional elements, such as the substrate binding site and the salt bridge network on the matrix side of the carrier. To understand the consequences of impaired citrate transport on metabolism, the substrate specificity was also determined, showing that the human citrate carrier predominantly transports citrate, isocitrate, cis-aconitate, phosphoenolpyruvate and malate. Although D-2- and L-2 hydroxyglutaric aciduria is a metabolic hallmark of the disease, it is unlikely that the citrate carrier plays a significant role in the removal of hydroxyglutarate from the cytosol for oxidation to oxoglutarate in the mitochondrial matrix. In contrast, computer simulations of central metabolism predict that the export of citrate from the mitochondrion cannot be fully compensated by other pathways, restricting the cytosolic production of acetyl-CoA that is required for the synthesis of lipids, sterols, dolichols and ubiquinone, which in turn explains the severe disease phenotypes. Copyright © 2017. Published by Elsevier B.V.

  6. Spontaneous mutation of Dock7 results in lower trabecular bone mass and impaired periosteal expansion in aged female Misty mice.

    Science.gov (United States)

    Le, Phuong T; Bishop, Kathleen A; Maridas, David E; Motyl, Katherine J; Brooks, Daniel J; Nagano, Kenichi; Baron, Roland; Bouxsein, Mary L; Rosen, Clifford J

    2017-12-01

    Misty mice (m/m) have a loss of function mutation in Dock7 gene, a guanine nucleotide exchange factor, resulting in low bone mineral density, uncoupled bone remodeling and reduced bone formation. Dock7 has been identified as a modulator of osteoblast number and in vitro osteogenic differentiation in calvarial osteoblast culture. In addition, m/m exhibit reduced preformed brown adipose tissue innervation and temperature as well as compensatory increase in beige adipocyte markers. While the low bone mineral density phenotype is in part due to higher sympathetic nervous system (SNS) drive in young mice, it is unclear what effect aging would have in mice homozygous for the mutation in the Dock7 gene. We hypothesized that age-related trabecular bone loss and periosteal envelope expansion would be altered in m/m. To test this hypothesis, we comprehensively characterized the skeletal phenotype of m/m at 16, 32, 52, and 78wks of age. When compared to age-matched wild-type control mice (+/+), m/m had lower areal bone mineral density (aBMD) and areal bone mineral content (aBMC). Similarly, both femoral and vertebral BV/TV, Tb.N, and Conn.D were decreased in m/m while there was also an increase in Tb.Sp. As low bone mineral density and decreased trabecular bone were already present at 16wks of age in m/m and persisted throughout life, changes in age-related trabecular bone loss were not observed highlighting the role of Dock7 in controlling trabecular bone acquisition or bone loss prior to 16wks of age. Cortical thickness was also lower in the m/m across all ages. Periosteal and endosteal circumferences were higher in m/m compared to +/+ at 16wks. However, endosteal and periosteal expansion were attenuated in m/m, resulting in m/m having lower periosteal and endosteal circumferences by 78wks of age compared to +/+, highlighting the critical role of Dock7 in appositional bone expansion. Histomorphometry revealed that osteoblasts were nearly undetectable in m/m and marrow

  7. Calmodulin is essential for cardiac IKS channel gating and assembly: impaired function in long-QT mutations

    DEFF Research Database (Denmark)

    Shamgar, Liora; Ma, Lijuan; Schmitt, Nicole

    2006-01-01

    The slow IKS K+ channel plays a major role in repolarizing the cardiac action potential and consists of the assembly of KCNQ1 and KCNE1 subunits. Mutations in either KCNQ1 or KCNE1 genes produce the long-QT syndrome, a life-threatening ventricular arrhythmia. Here, we show that long-QT mutations ...

  8. Mutations affecting the SAND domain of DEAF1 cause intellectual disability with severe speech impairment and behavioral problems

    NARCIS (Netherlands)

    Silfhout, A.T. van; Rajamanickam, S.; Jensik, P.J.; Vergult, S.; Rocker, N. de; Newhall, K.J.; Raghavan, R.; Reardon, S.N.; Jarrett, K.; McIntyre, T.; Bulinski, J.; Ownby, S.L.; Huggenvik, J.I.; McKnight, G.S.; Rose, G.M.; Cai, X; Willaert, A.; Zweier, C.; Endele, S.; Ligt, J. de; Bon, B.W.M. van; Lugtenberg, D.; Vries, P.F. de; Veltman, J.A.; Bokhoven, H. van; Brunner, H.G.; Rauch, A.; Brouwer, A.P.M. de; Carvill, G.L.; Hoischen, A.; Mefford, H.C.; Eichler, E.E.; Vissers, L.E.L.M.; Menten, B.; Collard, M.W.; Vries, L.B.A. de

    2014-01-01

    Recently, we identified in two individuals with intellectual disability (ID) different de novo mutations in DEAF1, which encodes a transcription factor with an important role in embryonic development. To ascertain whether these mutations in DEAF1 are causative for the ID phenotype, we performed

  9. A combination of two truncating mutations in USH2A causes more severe and progressive hearing impairment in Usher syndrome type IIa

    DEFF Research Database (Denmark)

    Hartel, Bas P.; Lofgren, Maria; Huygen, Patrick L. M.

    2016-01-01

    Objectives Usher syndrome is an inherited disorder that is characterized by hearing impairment (HI), retinitis pigmentosa, and in some cases vestibular dysfunction. Usher syndrome type IIa is caused by mutations in USH2A. HI in these patients is highly heterogeneous and the present study evaluates...... the effects of different types of USH2A mutations on the audiometric phenotype. Data from two large centres of expertise on Usher Syndrome in the Netherlands and Sweden were combined in order to create a large combined sample of patients to identify possible genotype-phenotype correlations. Design...... A retrospective study on HI in 110 patients (65 Dutch and 45 Swedish) genetically diagnosed with Usher syndrome type IIa. We used methods especially designed for characterizing and testing differences in audiological phenotype between patient subgroups. These methods included Age Related Typical Audiograms (ARTA...

  10. Gene structure and mutations of glutaryl-coenzyme A dehydrogenase: impaired association of enzyme subunits that is due to an A421V substitution causes glutaric acidemia type I in the Amish.

    Science.gov (United States)

    Biery, B J; Stein, D E; Morton, D H; Goodman, S I

    1996-11-01

    The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span approximately 7 kb. Fibroblast DNA from 64 unrelated glutaric acidemia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms found in 7 of its 11 exons. Several mutations were found in more than one patient, but no one prevalent mutation was detected in the general population. As expected from pedigree analysis, a single mutant allele causes GA1 in the Old Order Amish of Lancaster County, Pennsylvania. Several mutations have been expressed in Escherichia coli, and all produce diminished enzyme activity. Reduced activity in GCD encoded by the A421V mutation in the Amish may be due to impaired association of enzyme subunits.

  11. Mitochondrial Dysfunction Contributes to Impaired Insulin Secretion in INS-1 Cells with Dominant-negative Mutations of HNF-1α and in HNF-1α-deficient Islets*

    Science.gov (United States)

    Pongratz, Rebecca L.; Kibbey, Richard G.; Kirkpatrick, Clare L.; Zhao, Xiaojian; Pontoglio, Marco; Yaniv, Moshe; Wollheim, Claes B.; Shulman, Gerald I.; Cline, Gary W.

    2009-01-01

    Maturity Onset Diabetes of the Young-type 3 (MODY-3) has been linked to mutations in the transcription factor hepatic nuclear factor (HNF)-1α, resulting in deficiency in glucose-stimulated insulin secretion. In INS-1 cells overexpressing doxycycline-inducible HNF-1α dominant-negative (DN-) gene mutations, and islets from Hnf-1α knock-out mice, insulin secretion was impaired in response to glucose (15 mm) and other nutrient secretagogues. Decreased rates of insulin secretion in response to glutamine plus leucine and to methyl pyruvate, but not potassium depolarization, indicate defects specific to mitochondrial metabolism. To identify the biochemical mechanisms responsible for impaired insulin secretion, we used 31P NMR measured mitochondrial ATP synthesis (distinct from glycolytic ATP synthesis) together with oxygen consumption measurements to determine the efficiency of mitochondrial oxidative phosphorylation. Mitochondrial uncoupling was significantly higher in DN-HNF-1α cells, such that rates of ATP synthesis were decreased by approximately one-half in response to the secretagogues glucose, glutamine plus leucine, or pyruvate. In addition to closure of the ATP-sensitive K+ channels with mitochondrial ATP synthesis, mitochondrial production of second messengers through increased anaplerotic flux has been shown to be critical for coupling metabolism to insulin secretion. 13C-Isotopomer analysis and tandem mass spectrometry measurement of Krebs cycle intermediates revealed a negative impact of DN-HNF-1α and Hnf-1α knock-out on mitochondrial second messenger production with glucose but not amino acids. Taken together, these results indicate that, in addition to reduced glycolytic flux, uncoupling of mitochondrial oxidative phosphorylation contributes to impaired nutrient-stimulated insulin secretion with either mutations or loss of HNF-1α. PMID:19376774

  12. N1421K mutation in the glycoprotein Ib binding domain impairs ristocetin- and botrocetin-mediated binding of von Willebrand factor to platelets

    DEFF Research Database (Denmark)

    Lanke, E.; Kristoffersson, A.C.; Isaksson, C.

    2008-01-01

    , moderately decreased plasma factor VIII (FVIII) and VWF levels, and disproportionately low-plasma VWF:RCo levels. The patients were found to be heterozygous for the novel N1421K mutation, caused by a 4263C > G transversion in exon 28 of the VWF gene coding for the A1 domain. Botrocetin- and ristocetin-mediated...... binding of plasma VWF to GPIb were reduced in the patients. In vitro mutagenesis and expression in COS-7 cells confirmed the impairment of the mutant in botrocetin- and ristocetin-mediated VWF binding to GPIb. VWF collagen binding capacity was unaffected in plasma from the heterozygous individuals as well...

  13. The FTD-like syndrome causing TREM2 T66M mutation impairs microglia function, brain perfusion, and glucose metabolism.

    Science.gov (United States)

    Kleinberger, Gernot; Brendel, Matthias; Mracsko, Eva; Wefers, Benedikt; Groeneweg, Linda; Xiang, Xianyuan; Focke, Carola; Deußing, Maximilian; Suárez-Calvet, Marc; Mazaheri, Fargol; Parhizkar, Samira; Pettkus, Nadine; Wurst, Wolfgang; Feederle, Regina; Bartenstein, Peter; Mueggler, Thomas; Arzberger, Thomas; Knuesel, Irene; Rominger, Axel; Haass, Christian

    2017-07-03

    Genetic variants in the triggering receptor expressed on myeloid cells 2 (TREM2) increase the risk for several neurodegenerative diseases including Alzheimer's disease and frontotemporal dementia (FTD). Homozygous TREM2 missense mutations, such as p.T66M, lead to the FTD-like syndrome, but how they cause pathology is unknown. Using CRISPR/Cas9 genome editing, we generated a knock-in mouse model for the disease-associated Trem2 p.T66M mutation. Consistent with a loss-of-function mutation, we observe an intracellular accumulation of immature mutant Trem2 and reduced generation of soluble Trem2 similar to patients with the homozygous p.T66M mutation. Trem2 p.T66M knock-in mice show delayed resolution of inflammation upon in vivo lipopolysaccharide stimulation and cultured macrophages display significantly reduced phagocytic activity. Immunohistochemistry together with in vivo TSPO small animal positron emission tomography (μPET) demonstrates an age-dependent reduction in microglial activity. Surprisingly, perfusion magnetic resonance imaging and FDG-μPET imaging reveal a significant reduction in cerebral blood flow and brain glucose metabolism. Thus, we demonstrate that a TREM2 loss-of-function mutation causes brain-wide metabolic alterations pointing toward a possible function of microglia in regulating brain glucose metabolism. © 2017 The Authors.

  14. Novel hypomorphic mutation in IKBKG impairs NEMO-ubiquitylation causing ectodermal dysplasia, immunodeficiency, incontinentia pigmenti, and immune thrombocytopenic purpura.

    Science.gov (United States)

    Ramírez-Alejo, Noé; Alcántara-Montiel, Julio C; Yamazaki-Nakashimada, Marco; Duran-McKinster, Carola; Valenzuela-León, Paola; Rivas-Larrauri, Francisco; Cedillo-Barrón, Leticia; Hernández-Rivas, Rosaura; Santos-Argumedo, Leopoldo

    2015-10-01

    NF-κB essential modulator (NEMO) is a component of the IKK complex, which participates in the activation of the NF-κB pathway. Hypomorphic mutations in the IKBKG gene result in different forms of anhidrotic ectodermal dysplasia with immunodeficiency (EDA-ID) in males without affecting carrier females. Here, we describe a hypomorphic and missense mutation, designated c.916G>A (p.D306N), which affects our patient, his mother, and his sister. This mutation did not affect NEMO expression; however, an immunoprecipitation assay revealed reduced ubiquitylation upon CD40-stimulation in the patient's cells. Functional studies have demonstrated reduced phosphorylation and degradation of IκBα, affecting NF-κB recruitment into the nucleus. The patient presented with clinical features of ectodermal dysplasia, immunodeficiency, and immune thrombocytopenic purpura, the latter of which has not been previously reported in a patient with NEMO deficiency. His mother and sister displayed incontinentia pigmenti indicating that, in addition to amorphic mutations, hypomorphic mutations in NEMO can affect females. Copyright © 2015 Elsevier Inc. All rights reserved.

  15. Homozygous SLC6A17 Mutations Cause Autosomal-Recessive Intellectual Disability with Progressive Tremor, Speech Impairment, and Behavioral Problems

    NARCIS (Netherlands)

    Iqbal, Z.; Willemsen, M.H.; Papon, M.A.; Musante, L.; Benevento, M.; Hu, H; Venselaar, H.; Wissink-Lindhout, W.M.; Silfhout, A.T. van; Vissers, L.E.L.M.; Brouwer, A.P.M. de; Marouillat, S.; Wienker, T.F.; Ropers, H.H.; Kahrizi, K.; Nadif Kasri, N.; Najmabadi, H.; Laumonnier, F.; Kleefstra, T.; Bokhoven, H. van

    2015-01-01

    We report on Dutch and Iranian families with affected individuals who present with moderate to severe intellectual disability and additional phenotypes including progressive tremor, speech impairment, and behavioral problems in certain individuals. A combination of exome sequencing and homozygosity

  16. A combination of two truncating mutations in USH2A causes more severe and progressive hearing impairment in Usher syndrome type IIa.

    Science.gov (United States)

    Hartel, Bas P; Löfgren, Maria; Huygen, Patrick L M; Guchelaar, Iris; Lo-A-Njoe Kort, Nicole; Sadeghi, Andre M; van Wijk, Erwin; Tranebjærg, Lisbeth; Kremer, Hannie; Kimberling, William J; Cremers, Cor W R J; Möller, Claes; Pennings, Ronald J E

    2016-09-01

    Usher syndrome is an inherited disorder that is characterized by hearing impairment (HI), retinitis pigmentosa, and in some cases vestibular dysfunction. Usher syndrome type IIa is caused by mutations in USH2A. HI in these patients is highly heterogeneous and the present study evaluates the effects of different types of USH2A mutations on the audiometric phenotype. Data from two large centres of expertise on Usher Syndrome in the Netherlands and Sweden were combined in order to create a large combined sample of patients to identify possible genotype-phenotype correlations. A retrospective study on HI in 110 patients (65 Dutch and 45 Swedish) genetically diagnosed with Usher syndrome type IIa. We used methods especially designed for characterizing and testing differences in audiological phenotype between patient subgroups. These methods included Age Related Typical Audiograms (ARTA) and a method to evaluate the difference in the degree of HI developed throughout life between subgroups. Cross-sectional linear regression analysis of last-visit audiograms for the best hearing ear demonstrated a gradual decline of hearing over decades. The congenital level of HI was in the range of 16-33 dB at 0.25-0.5 kHz, and in the range of 51-60 dB at 1-8 kHz. The annual threshold deterioration was in the range of 0.4-0.5 dB/year at 0.25-2 kHz and in the range of 0.7-0.8 dB/year at 4-8 kHz. Patients with two truncating mutations, including homozygotes for the common c.2299delG mutation, developed significantly more severe HI throughout life than patients with one truncating mutation combined with one nontruncating mutation, and patients with two nontruncating mutations. The results have direct implications for patient counselling in terms of prognosis of hearing and may serve as baseline measures for future (genetic) therapeutic interventions. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Age-Related Hearing Impairment (ARHI) associated with GJB2 single mutation IVS1+1G>A in the Yakut population isolate in Eastern Siberia.

    Science.gov (United States)

    Barashkov, Nikolay A; Teryutin, Fedor M; Pshennikova, Vera G; Solovyev, Aisen V; Klarov, Leonid A; Solovyeva, Natalya A; Kozhevnikov, Andrei A; Vasilyeva, Lena M; Fedotova, Elvira E; Pak, Maria V; Lekhanova, Sargylana N; Zakharova, Elena V; Savvinova, Kyunney E; Gotovtsev, Nyurgun N; Rafailo, Adyum M; Luginov, Nikolay V; Alexeev, Anatoliy N; Posukh, Olga L; Dzhemileva, Lilya U; Khusnutdinova, Elza K; Fedorova, Sardana A

    2014-01-01

    Age-Related Hearing Impairment (ARHI) is one of the frequent sensory disorders registered in 50% of individuals over 80 years. ARHI is a multifactorial disorder due to environmental and poor-known genetic components. In this study, we present the data on age-related hearing impairment of 48 heterozygous carriers of mutation IVS1+1G>A (GJB2 gene) and 97 subjects with GJB2 genotype wt/wt in the Republic of Sakha/Yakutia (Eastern Siberia, Russia). This subarctic territory was found as the region with the most extensive accumulation of mutation IVS1+1G>A in the world as a result of founder effect in the unique Yakut population isolate. The GJB2 gene resequencing and detailed audiological analysis in the frequency range 0.25, 0.5, 1.0, 2.0, 4.0, 8.0 kHz were performed in all examined subjects that allowed to investigate genotype-phenotype correlations between the presence of single mutation IVS1+1G>A and hearing of subjects from examined groups. We revealed the linear correlation between increase of average hearing thresholds at speech frequencies (PTA0.5,1.0,2.0,4.0 kHz) and age of individuals with GJB2 genotype IVS1+1G>A/wt (rs = 0.499, p = 0.006860 for males and rs = 0.427, p = 0.000277 for females). Moreover, the average hearing thresholds on high frequency (8.0 kHz) in individuals with genotype IVS1+1G>A/wt (both sexes) were significantly worse than in individuals with genotype wt/wt (pA/wt was estimated to be ∼40 years (rs = 0.504, p = 0.003). These findings demonstrate that the single IVS1+1G>A mutation (GJB2) is associated with age-related hearing impairment (ARHI) of the IVS1+1G>A carriers in the Yakuts.

  18. Age-Related Hearing Impairment (ARHI associated with GJB2 single mutation IVS1+1G>A in the Yakut population isolate in Eastern Siberia.

    Directory of Open Access Journals (Sweden)

    Nikolay A Barashkov

    Full Text Available Age-Related Hearing Impairment (ARHI is one of the frequent sensory disorders registered in 50% of individuals over 80 years. ARHI is a multifactorial disorder due to environmental and poor-known genetic components. In this study, we present the data on age-related hearing impairment of 48 heterozygous carriers of mutation IVS1+1G>A (GJB2 gene and 97 subjects with GJB2 genotype wt/wt in the Republic of Sakha/Yakutia (Eastern Siberia, Russia. This subarctic territory was found as the region with the most extensive accumulation of mutation IVS1+1G>A in the world as a result of founder effect in the unique Yakut population isolate. The GJB2 gene resequencing and detailed audiological analysis in the frequency range 0.25, 0.5, 1.0, 2.0, 4.0, 8.0 kHz were performed in all examined subjects that allowed to investigate genotype-phenotype correlations between the presence of single mutation IVS1+1G>A and hearing of subjects from examined groups. We revealed the linear correlation between increase of average hearing thresholds at speech frequencies (PTA0.5,1.0,2.0,4.0 kHz and age of individuals with GJB2 genotype IVS1+1G>A/wt (rs = 0.499, p = 0.006860 for males and rs = 0.427, p = 0.000277 for females. Moreover, the average hearing thresholds on high frequency (8.0 kHz in individuals with genotype IVS1+1G>A/wt (both sexes were significantly worse than in individuals with genotype wt/wt (pA/wt was estimated to be ∼40 years (rs = 0.504, p = 0.003. These findings demonstrate that the single IVS1+1G>A mutation (GJB2 is associated with age-related hearing impairment (ARHI of the IVS1+1G>A carriers in the Yakuts.

  19. Impaired riboflavin transport due to missense mutations in SLC52A2 causes Brown-Vialetto-Van Laere syndrome

    OpenAIRE

    Haack, Tobias B.; Makowski, Christine; Yao, Yoshiaki; Graf, Elisabeth; Hempel, Maja; Wieland, Thomas; Tauer, Ulrike; Ahting, Uwe; Mayr, Johannes A.; Freisinger, Peter; Yoshimatsu, Hiroki; Inui, Ken; Strom, Tim M.; Meitinger, Thomas; Yonezawa, Atsushi

    2012-01-01

    Brown-Vialetto-Van Laere syndrome (BVVLS [MIM 211530]) is a rare neurological disorder characterized by infancy onset sensorineural deafness and ponto-bulbar palsy. Mutations in SLC52A3 (formerly C20orf54), coding for riboflavin transporter 2 (hRFT2), have been identified as the molecular genetic correlate in several individuals with BVVLS. Exome sequencing of just one single case revealed that compound heterozygosity for two pathogenic mutations in the SLC52A2 gene coding for riboflavin tran...

  20. Frequency of c.35delG Mutation in GJB2 Gene (Connexin 26 in Syrian Patients with Nonsyndromic Hearing Impairment

    Directory of Open Access Journals (Sweden)

    Hazem Kaheel

    2017-01-01

    Full Text Available Background. Hearing impairments (HI are the most common birth defect worldwide. Very large numbers of genes have been identified but the most profound is GJB2. The clinical interest regarding this gene is very pronounced due to its high carrier frequency (0.5–5.4% across different ethnic groups. This study aimed to determine the prevalence of common GJB2 mutations in Syrian patients with profound sensorineural HI. Methods. We carried out PCR, restriction enzyme based screening, and sequencing of 132 Syrian patients diagnosed clinically with hereditary deafness for different GJB2 mutations. Results. The result revealed that, in GJB2 gene, c.35delG is the most prevalent among affected studied subjects (13.64%, followed by c.457G>A (2.4%. Conclusion. The benefit of this study on the one hand is its first report of prelingual deafness causative gene mutations identified by sequencing technology in the Syrian families. It is obvious from the results that the deployment in biomedical research is highly effective and has a great impact on the ability to uncover the cause of genetic variation in different genetic diseases.

  1. Mice with an Oncogenic HRAS Mutation are Resistant to High-Fat Diet-Induced Obesity and Exhibit Impaired Hepatic Energy Homeostasis

    Directory of Open Access Journals (Sweden)

    Daiju Oba

    2018-01-01

    Full Text Available Costello syndrome is a “RASopathy” that is characterized by growth retardation, dysmorphic facial appearance, hypertrophic cardiomyopathy and tumor predisposition. >80% of patients with Costello syndrome harbor a heterozygous germline G12S mutation in HRAS. Altered metabolic regulation has been suspected because patients with Costello syndrome exhibit hypoketotic hypoglycemia and increased resting energy expenditure, and their growth is severely retarded. To examine the mechanisms of energy reprogramming by HRAS activation in vivo, we generated knock-in mice expressing a heterozygous Hras G12S mutation (HrasG12S/+ mice as a mouse model of Costello syndrome. On a high-fat diet, HrasG12S/+ mice developed a lean phenotype with microvesicular hepatic steatosis, resulting in early death compared with wild-type mice. Under starvation conditions, hypoketosis and elevated blood levels of long-chain fatty acylcarnitines were observed, suggesting impaired mitochondrial fatty acid oxidation. Our findings suggest that the oncogenic Hras mutation modulates energy homeostasis in vivo.

  2. Herpes Simplex Virus 1 Mutant with Point Mutations in UL39 Is Impaired for Acute Viral Replication in Mice, Establishment of Latency, and Explant-Induced Reactivation.

    Science.gov (United States)

    Mostafa, Heba H; Thompson, Thornton W; Konen, Adam J; Haenchen, Steve D; Hilliard, Joshua G; Macdonald, Stuart J; Morrison, Lynda A; Davido, David J

    2018-04-01

    In the process of generating herpes simplex virus 1 (HSV-1) mutations in the viral regulatory gene encoding infected cell protein 0 (ICP0), we isolated a viral mutant, termed KOS-NA, that was severely impaired for acute replication in the eyes and trigeminal ganglia (TG) of mice, defective in establishing a latent infection, and reactivated poorly from explanted TG. To identify the secondary mutation(s) responsible for the impaired phenotypes of this mutant, we sequenced the KOS-NA genome and noted that it contained two nonsynonymous mutations in UL39 , which encodes the large subunit of ribonucleotide reductase, ICP6. These mutations resulted in lysine-to-proline (residue 393) and arginine-to-histidine (residue 950) substitutions in ICP6. To determine whether alteration of these amino acids was responsible for the KOS-NA phenotypes in vivo , we recombined the wild-type UL39 gene into the KOS-NA genome and rescued its acute replication phenotypes in mice. To further establish the role of UL39 in KOS-NA's decreased pathogenicity, the UL39 mutations were recombined into HSV-1 (generating UL39 mut ), and this mutant virus showed reduced ocular and TG replication in mice comparable to that of KOS-NA. Interestingly, ICP6 protein levels were reduced in KOS-NA-infected cells relative to the wild-type protein. Moreover, we observed that KOS-NA does not counteract caspase 8-induced apoptosis, unlike wild-type strain KOS. Based on alignment studies with other HSV-1 ICP6 homologs, our data suggest that amino acid 950 of ICP6 likely plays an important role in ICP6 accumulation and inhibition of apoptosis, consequently impairing HSV-1 pathogenesis in a mouse model of HSV-1 infection. IMPORTANCE HSV-1 is a major human pathogen that infects ∼80% of the human population and can be life threatening to infected neonates or immunocompromised individuals. Effective therapies for treatment of recurrent HSV-1 infections are limited, which emphasizes a critical need to understand in

  3. Vigorous physical activity impairs myocardial function in patients with arrhythmogenic right ventricular cardiomyopathy and in mutation positive family members

    DEFF Research Database (Denmark)

    Saberniak, Jørg; Hasselberg, Nina E; Borgquist, Rasmus

    2014-01-01

    patients and 45 mutation-positive family members. Athletes were defined as subjects with ≥4 h vigorous exercise/week [≥1440 metabolic equivalents (METs × minutes/week)] during a minimum of 6 years. Athlete definition was fulfilled in 37/110 (34%) subjects. We assessed right ventricular (RV) and left...

  4. Early microgliosis precedes neuronal loss and behavioural impairment in mice with a frontotemporal dementia-causing CHMP2B mutation

    DEFF Research Database (Denmark)

    Clayton, Emma L.; Mancuso, Renzo; Nielsen, Troels Tolstrup

    2017-01-01

    Frontotemporal dementia (FTD)-causing mutations in the CHMP2B gene lead to the generation of mutant C-terminally truncated CHMP2B. We report that transgenic mice expressing endogenous levels of mutant CHMP2B developed late-onset brain volume loss associated with frank neuronal loss and FTD-like c...

  5. Founder effect in the Horn of Africa for an insulin receptor mutation that may impair receptor recycling

    DEFF Research Database (Denmark)

    Raffan, E; Soos, M A; Rocha, N

    2011-01-01

    Genetic insulin receptoropathies are a rare cause of severe insulin resistance. We identified the Ile119Met missense mutation in the insulin receptor INSR gene, previously reported in a Yemeni kindred, in four unrelated patients with Somali ancestry. We aimed to investigate a possible genetic...

  6. Loss-of-function mutations in ATP6V0A2 impair vesicular trafficking, tropoelastin secretion and cell survival.

    NARCIS (Netherlands)

    Hucthagowder, V.; Morava, E.; Kornak, U.; Lefeber, D.J.; Fischer, B.; Dimopoulou, A.; Aldinger, A.; Choi, J.; Davis, E.C.; Abuelo, D.N.; Adamowicz, M.; Al-Aama, J.Y.; Basel-Vanagaite, L.; Fernandez, B.; Greally, M.T.; Gillessen-Kaesbach, G.; Kayserili, H.; Lemyre, E.; Tekin, M.; Turkmen, S.; Tuysuz, B.; Yuksel-Konuk, B.; Mundlos, S.; Maldergem, L. van; Wevers, R.A.; Urban, Z.

    2009-01-01

    Autosomal recessive cutis laxa type 2 (ARCL2), a syndrome of growth and developmental delay and redundant, inelastic skin, is caused by mutations in the a2 subunit of the vesicular ATPase H+-pump (ATP6V0A2). The goal of this study was to define the disease mechanisms that lead to connective tissue

  7. A novel mutation in the WFS1 gene identified in a Taiwanese family with low-frequency hearing impairment

    Directory of Open Access Journals (Sweden)

    Chung Shing-Fang

    2007-05-01

    Full Text Available Abstract Background Wolfram syndrome gene 1 (WFS1 accounts for most of the familial nonsyndromic low-frequency sensorineural hearing loss (LFSNHL which is characterized by sensorineural hearing losses equal to and below 2000 Hz. The current study aimed to contribute to our understanding of the molecular basis of LFSNHL in an affected Taiwanese family. Methods The Taiwanese family with LFSNHL was phenotypically characterized using audiologic examination and pedigree analysis. Genetic characterization was performed by direct sequencing of WFS1 and mutation analysis. Results Pure tone audiometry confirmed that the family members affected with LFSNHL had a bilateral sensorineural hearing loss equal to or below 2000 Hz. The hearing loss threshold of the affected members showed no progression, a characteristic that was consistent with a mutation in the WFS1 gene located in the DFNA6/14/38 locus. Pedigree analysis showed a hereditarily autosomal dominant pattern characterized by a full penetrance. Among several polymorphisms, a missense mutation Y669H (2005T>C in exon 8 of WFS1 was identified in members of a Taiwanese family diagnosed with LFSNHL but not in any of the control subjects. Conclusion We discovered a novel heterozygous missense mutation in exon 8 of WFS1 (i.e., Y669H which is likely responsible for the LFSNHL phenotype in this particular Taiwanese family.

  8. Depolarized inactivation overcomes impaired activation to produce DRG neuron hyperexcitability in a Nav1.7 mutation in a patient with distal limb pain.

    Science.gov (United States)

    Huang, Jianying; Yang, Yang; Dib-Hajj, Sulayman D; van Es, Michael; Zhao, Peng; Salomon, Jody; Drenth, Joost P H; Waxman, Stephen G

    2014-09-10

    Sodium channel Nav1.7, encoded by SCN9A, is expressed in DRG neurons and regulates their excitability. Genetic and functional studies have established a critical contribution of Nav1.7 to human pain disorders. We have now characterized a novel Nav1.7 mutation (R1279P) from a female human subject with distal limb pain, in which depolarized fast inactivation overrides impaired activation to produce hyperexcitability and spontaneous firing in DRG neurons. Whole-cell voltage-clamp recordings in human embryonic kidney (HEK) 293 cells demonstrated that R1279P significantly depolarizes steady-state fast-, slow-, and closed-state inactivation. It accelerates deactivation, decelerates inactivation, and facilitates repriming. The mutation increases ramp currents in response to slow depolarizations. Our voltage-clamp analysis showed that R1279P depolarizes channel activation, a change that was supported by our multistate structural modeling. Because this mutation confers both gain-of-function and loss-of-function attributes on the Nav1.7 channel, we tested the impact of R1279P expression on DRG neuron excitability. Current-clamp studies reveal that R1279P depolarizes resting membrane potential, decreases current threshold, and increases firing frequency of evoked action potentials within small DRG neurons. The populations of spontaneously firing and repetitively firing neurons were increased by expressing R1279P. These observations indicate that the dominant proexcitatory gating changes associated with this mutation, including depolarized steady-state fast-, slow-, and closed-state inactivation, faster repriming, and larger ramp currents, override the depolarizing shift of activation, to produce hyperexcitability and spontaneous firing of nociceptive neurons that underlie pain. Copyright © 2014 the authors 0270-6474/14/3412328-13$15.00/0.

  9. Metabolite profiles reveal energy failure and impaired beta-oxidation in liver of mice with complex III deficiency due to a BCS1L mutation.

    Directory of Open Access Journals (Sweden)

    Heike Kotarsky

    Full Text Available BACKGROUND & AIMS: Liver is a target organ in many mitochondrial disorders, especially if the complex III assembly factor BCS1L is mutated. To reveal disease mechanism due to such mutations, we have produced a transgenic mouse model with c.232A>G mutation in Bcs1l, the causative mutation for GRACILE syndrome. The homozygous mice develop mitochondrial hepatopathy with steatosis and fibrosis after weaning. Our aim was to assess cellular mechanisms for disease onset and progression using metabolomics. METHODS: With mass spectrometry we analyzed metabolite patterns in liver samples obtained from homozygotes and littermate controls of three ages. As oxidative stress might be a mechanism for mitochondrial hepatopathy, we also assessed H(2O(2 production and expression of antioxidants. RESULTS: Homozygotes had a similar metabolic profile at 14 days of age as controls, with the exception of slightly decreased AMP. At 24 days, when hepatocytes display first histopathological signs, increases in succinate, fumarate and AMP were found associated with impaired glucose turnover and beta-oxidation. At end stage disease after 30 days, these changes were pronounced with decreased carbohydrates, high levels of acylcarnitines and amino acids, and elevated biogenic amines, especially putrescine. Signs of oxidative stress were present in end-stage disease. CONCLUSIONS: The findings suggest an early Krebs cycle defect with increases of its intermediates, which might play a role in disease onset. During disease progression, carbohydrate and fatty acid metabolism deteriorate leading to a starvation-like condition. The mouse model is valuable for further investigations on mechanisms in mitochondrial hepatopathy and for interventions.

  10. ZC4H2 Mutations Are Associated with Arthrogryposis Multiplex Congenita and Intellectual Disability through Impairment of Central and Peripheral Synaptic Plasticity

    Science.gov (United States)

    Hirata, Hiromi; Nanda, Indrajit; van Riesen, Anne; McMichael, Gai; Hu, Hao; Hambrock, Melanie; Papon, Marie-Amélie; Fischer, Ute; Marouillat, Sylviane; Ding, Can; Alirol, Servane; Bienek, Melanie; Preisler-Adams, Sabine; Grimme, Astrid; Seelow, Dominik; Webster, Richard; Haan, Eric; MacLennan, Alastair; Stenzel, Werner; Yap, Tzu Ying; Gardner, Alison; Nguyen, Lam Son; Shaw, Marie; Lebrun, Nicolas; Haas, Stefan A.; Kress, Wolfram; Haaf, Thomas; Schellenberger, Elke; Chelly, Jamel; Viot, Géraldine; Shaffer, Lisa G.; Rosenfeld, Jill A.; Kramer, Nancy; Falk, Rena; El-Khechen, Dima; Escobar, Luis F.; Hennekam, Raoul; Wieacker, Peter; Hübner, Christoph; Ropers, Hans-Hilger; Gecz, Jozef; Schuelke, Markus; Laumonnier, Frédéric; Kalscheuer, Vera M.

    2013-01-01

    Arthrogryposis multiplex congenita (AMC) is caused by heterogeneous pathologies leading to multiple antenatal joint contractures through fetal akinesia. Understanding the pathophysiology of this disorder is important for clinical care of the affected individuals and genetic counseling of the families. We thus aimed to establish the genetic basis of an AMC subtype that is associated with multiple dysmorphic features and intellectual disability (ID). We used haplotype analysis, next-generation sequencing, array comparative genomic hybridization, and chromosome breakpoint mapping to identify the pathogenic mutations in families and simplex cases. Suspected disease variants were verified by cosegregation analysis. We identified disease-causing mutations in the zinc-finger gene ZC4H2 in four families affected by X-linked AMC plus ID and one family affected by cerebral palsy. Several heterozygous females were also affected, but to a lesser degree. Furthermore, we found two ZC4H2 deletions and one rearrangement in two female and one male unrelated simplex cases, respectively. In mouse primary hippocampal neurons, transiently produced ZC4H2 localized to the postsynaptic compartment of excitatory synapses, and the altered protein influenced dendritic spine density. In zebrafish, antisense-morpholino-mediated zc4h2 knockdown caused abnormal swimming and impaired α-motoneuron development. All missense mutations identified herein failed to rescue the swimming defect of zebrafish morphants. We conclude that ZC4H2 point mutations, rearrangements, and small deletions cause a clinically variable broad-spectrum neurodevelopmental disorder of the central and peripheral nervous systems in both familial and simplex cases of both sexes. Our results highlight the importance of ZC4H2 for genetic testing of individuals presenting with ID plus muscle weakness and minor or major forms of AMC. PMID:23623388

  11. Impaired riboflavin transport due to missense mutations in SLC52A2 causes Brown-Vialetto-Van Laere syndrome.

    Science.gov (United States)

    Haack, Tobias B; Makowski, Christine; Yao, Yoshiaki; Graf, Elisabeth; Hempel, Maja; Wieland, Thomas; Tauer, Ulrike; Ahting, Uwe; Mayr, Johannes A; Freisinger, Peter; Yoshimatsu, Hiroki; Inui, Ken; Strom, Tim M; Meitinger, Thomas; Yonezawa, Atsushi; Prokisch, Holger

    2012-11-01

    Brown-Vialetto-Van Laere syndrome (BVVLS [MIM 211530]) is a rare neurological disorder characterized by infancy onset sensorineural deafness and ponto-bulbar palsy. Mutations in SLC52A3 (formerly C20orf54), coding for riboflavin transporter 2 (hRFT2), have been identified as the molecular genetic correlate in several individuals with BVVLS. Exome sequencing of just one single case revealed that compound heterozygosity for two pathogenic mutations in the SLC52A2 gene coding for riboflavin transporter 3 (hRFT3), another member of the riboflavin transporter family, is also associated with BVVLS. Overexpression studies confirmed that the gene products of both mutant alleles have reduced riboflavin transport activities. While mutations in SLC52A3 cause decreased plasma riboflavin levels, concordant with a role of SLC52A3 in riboflavin uptake from food, the SLC52A2-mutant individual had normal plasma riboflavin concentrations, a finding in line with a postulated function of SLC52A2 in riboflavin uptake from blood into target cells. Our results contribute to the understanding of human riboflavin metabolism and underscore its role in the pathogenesis of BVVLS, thereby providing a rational basis for a high-dose riboflavin treatment.

  12. The Mass1frings mutation underlies early onset hearing impairment in BUB/BnJ mice, a model for the auditory pathology of Usher syndrome IIC

    Science.gov (United States)

    Johnson, K.R.; Zheng, Q.Y.; Weston, M.D.; Ptacek, L.J.; Noben-Trauth, K.

    2010-01-01

    The human ortholog of the gene responsible for audiogenic seizure susceptibility in Frings and BUB/BnJ mice (mouse gene symbol Mass1) recently was shown to underlie Usher syndrome type IIC (USH2C). Here we report that the Mass1frings mutation is responsible for the early onset hearing impairment of BUB/BnJ mice. We found highly significant linkage of Mass1 with ABR threshold variation among mice from two backcrosses involving BUB/BnJ mice with mice of strains CAST/EiJ and MOLD/RkJ. We also show an additive effect of the Cdh23 locus in modulating the progression of hearing loss in backcross mice. Together, these two loci account for more than 70% of the total ABR threshold variation among the backcross mice at all ages. The modifying effect of the strain-specific Cdh23ahl variant may account for the hearing and audiogenic seizure differences observed between Frings and BUB/BnJ mice, which share the Mass1frings mutation. During postnatal cochlear development in BUB/BnJ mice, stereocilia bundles develop abnormally and remain immature and splayed into adulthood, corresponding with the early onset hearing impairment associated with Mass1frings. Progressive base–apex hair cell degeneration occurs at older ages, corresponding with the age-related hearing loss associated with Cdh23ahl. The molecular basis and pathophysiology of hearing loss suggest BUB/BnJ and Frings mice as models to study cellular and molecular mechanisms underlying USH2C auditory pathology. PMID:15820310

  13. Mutations in Mll2, an H3K4 Methyltransferase, Result in Insulin Resistance and Impaired Glucose Tolerance in Mice

    Science.gov (United States)

    Schröter, David; Matthews, Helen C.; Bogani, Debora; Moir, Lee; Long, Anna; Church, Christopher; Hugill, Alison; Anstee, Quentin M.; Goldin, Rob; Thursz, Mark; Hollfelder, Florian; Cox, Roger D.

    2013-01-01

    We employed a random mutagenesis approach to identify novel monogenic determinants of type 2 diabetes. Here we show that haplo-insufficiency of the histone methyltransferase myeloid-lineage leukemia (Mll2/Wbp7) gene causes type 2 diabetes in the mouse. We have shown that mice heterozygous for two separate mutations in the SET domain of Mll2 or heterozygous Mll2 knockout mice were hyperglycaemic, hyperinsulinaemic and developed non-alcoholic fatty liver disease. Consistent with previous Mll2 knockout studies, mice homozygous for either ENU mutation (or compound heterozygotes) died during embryonic development at 9.5–14.5 days post coitum. Heterozygous deletion of Mll2 induced in the adult mouse results in a normal phenotype suggesting that changes in chromatin methylation during development result in the adult phenotype. Mll2 has been shown to regulate a small subset of genes, a number of which Neurod1, Enpp1, Slc27a2, and Plcxd1 are downregulated in adult mutant mice. Our results demonstrate that histone H3K4 methyltransferase Mll2 is a component of the genetic regulation necessary for glucose homeostasis, resulting in a specific disease pattern linking chromatin modification with causes and progression of type 2 diabetes, providing a basis for its further understanding at the molecular level. PMID:23826075

  14. Mutations in Mll2, an H3K4 methyltransferase, result in insulin resistance and impaired glucose tolerance in mice.

    Directory of Open Access Journals (Sweden)

    Michelle Goldsworthy

    Full Text Available We employed a random mutagenesis approach to identify novel monogenic determinants of type 2 diabetes. Here we show that haplo-insufficiency of the histone methyltransferase myeloid-lineage leukemia (Mll2/Wbp7 gene causes type 2 diabetes in the mouse. We have shown that mice heterozygous for two separate mutations in the SET domain of Mll2 or heterozygous Mll2 knockout mice were hyperglycaemic, hyperinsulinaemic and developed non-alcoholic fatty liver disease. Consistent with previous Mll2 knockout studies, mice homozygous for either ENU mutation (or compound heterozygotes died during embryonic development at 9.5-14.5 days post coitum. Heterozygous deletion of Mll2 induced in the adult mouse results in a normal phenotype suggesting that changes in chromatin methylation during development result in the adult phenotype. Mll2 has been shown to regulate a small subset of genes, a number of which Neurod1, Enpp1, Slc27a2, and Plcxd1 are downregulated in adult mutant mice. Our results demonstrate that histone H3K4 methyltransferase Mll2 is a component of the genetic regulation necessary for glucose homeostasis, resulting in a specific disease pattern linking chromatin modification with causes and progression of type 2 diabetes, providing a basis for its further understanding at the molecular level.

  15. Mutation in the B chain coding region is associated with impaired proinsulin conversion in a family with hyperproinsulinemia

    International Nuclear Information System (INIS)

    Chan, S.J.; Seino, S.; Gruppuso, P.A.; Schwartz, R.; Steiner, D.F.

    1987-01-01

    A family has recently been described in which hyperproinsulinemia is inherited in an autosomal dominant pattern, suggesting a structural abnormality in the proinsulin molecule as the basis for this disorder. However, unlike two previous kindreds with a similar syndrome, the serum proinsulin-like material in this family did not appear to be an intermediate conversion product but instead behaved like normal human proinsulin by several criteria. To further characterize this disorder the authors isolated and sequenced the insulin gene of the propositus. Leukocyte DNA was cloned in λgt-WES and recombinants containing the two insulin alleles, λMD41 and λMD51, were isolated by plaque hybridization. DNA sequencing of λMD51 showed that it contained the normal coding sequence for human preproinsulin. Sequence analysis of λMD41, however, revealed a single nucleotide substitution in the codon for residue 10 of proinsulin (CAC → GAC) that predicts the exchange of aspartic acid for histidine in the insulin B chain region. This mutation was also found in an insulin allele cloned from a second affected family member (propositus's father). These results strongly implicate this mutation as the cause of the hyperproinsulinemia in this family. Inhibition of the conversion of proinsulin to insulin may be related to altered folding and/or self-association properties of the [Asp 10 ]proinsulin

  16. WDR81 mutations cause extreme microcephaly and impair mitotic progression in human fibroblasts and Drosophila neural stem cells.

    Science.gov (United States)

    Cavallin, Mara; Rujano, Maria A; Bednarek, Nathalie; Medina-Cano, Daniel; Bernabe Gelot, Antoinette; Drunat, Severine; Maillard, Camille; Garfa-Traore, Meriem; Bole, Christine; Nitschké, Patrick; Beneteau, Claire; Besnard, Thomas; Cogné, Benjamin; Eveillard, Marion; Kuster, Alice; Poirier, Karine; Verloes, Alain; Martinovic, Jelena; Bidat, Laurent; Rio, Marlene; Lyonnet, Stanislas; Reilly, M Louise; Boddaert, Nathalie; Jenneson-Liver, Melanie; Motte, Jacques; Doco-Fenzy, Martine; Chelly, Jamel; Attie-Bitach, Tania; Simons, Matias; Cantagrel, Vincent; Passemard, Sandrine; Baffet, Alexandre; Thomas, Sophie; Bahi-Buisson, Nadia

    2017-10-01

    Microlissencephaly is a rare brain malformation characterized by congenital microcephaly and lissencephaly. Microlissencephaly is suspected to result from abnormalities in the proliferation or survival of neural progenitors. Despite the recent identification of six genes involved in microlissencephaly, the pathophysiological basis of this condition remains poorly understood. We performed trio-based whole exome sequencing in seven subjects from five non-consanguineous families who presented with either microcephaly or microlissencephaly. This led to the identification of compound heterozygous mutations in WDR81, a gene previously associated with cerebellar ataxia, intellectual disability and quadrupedal locomotion. Patient phenotypes ranged from severe microcephaly with extremely reduced gyration with pontocerebellar hypoplasia to moderate microcephaly with cerebellar atrophy. In patient fibroblast cells, WDR81 mutations were associated with increased mitotic index and delayed prometaphase/metaphase transition. Similarly, in vivo, we showed that knockdown of the WDR81 orthologue in Drosophila led to increased mitotic index of neural stem cells with delayed mitotic progression. In summary, we highlight the broad phenotypic spectrum of WDR81-related brain malformations, which include microcephaly with moderate to extremely reduced gyration and cerebellar anomalies. Our results suggest that WDR81 might have a role in mitosis that is conserved between Drosophila and humans. © The Author (2017). Published by Oxford University Press on behalf of the Guarantors of Brain. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. AP1S3 Mutations Are Associated with Pustular Psoriasis and Impaired Toll-like Receptor 3 Trafficking

    Science.gov (United States)

    Setta-Kaffetzi, Niovi; Simpson, Michael A.; Navarini, Alexander A.; Patel, Varsha M.; Lu, Hui-Chun; Allen, Michael H.; Duckworth, Michael; Bachelez, Hervé; Burden, A. David; Choon, Siew-Eng; Griffiths, Christopher E.M.; Kirby, Brian; Kolios, Antonios; Seyger, Marieke M.B.; Prins, Christa; Smahi, Asma; Trembath, Richard C.; Fraternali, Franca; Smith, Catherine H.; Barker, Jonathan N.; Capon, Francesca

    2014-01-01

    Adaptor protein complex 1 (AP-1) is an evolutionary conserved heterotetramer that promotes vesicular trafficking between the trans-Golgi network and the endosomes. The knockout of most murine AP-1 complex subunits is embryonically lethal, so the identification of human disease-associated alleles has the unique potential to deliver insights into gene function. Here, we report two founder mutations (c.11T>G [p.Phe4Cys] and c.97C>T [p.Arg33Trp]) in AP1S3, the gene encoding AP-1 complex subunit σ1C, in 15 unrelated individuals with a severe autoinflammatory skin disorder known as pustular psoriasis. Because the variants are predicted to destabilize the 3D structure of the AP-1 complex, we generated AP1S3-knockdown cell lines to investigate the consequences of AP-1 deficiency in skin keratinocytes. We found that AP1S3 silencing disrupted the endosomal translocation of the innate pattern-recognition receptor TLR-3 (Toll-like receptor 3) and resulted in a marked inhibition of downstream signaling. These findings identify pustular psoriasis as an autoinflammatory phenotype caused by defects in vesicular trafficking and demonstrate a requirement of AP-1 for Toll-like receptor homeostasis. PMID:24791904

  18. Induced pluripotent stem cells with NOTCH1 gene mutation show impaired differentiation into smooth muscle and endothelial cells: Implications for bicuspid aortic valve-related aortopathy.

    Science.gov (United States)

    Jiao, Jiao; Tian, Weihua; Qiu, Ping; Norton, Elizabeth L; Wang, Michael M; Chen, Y Eugene; Yang, Bo

    2018-03-12

    The NOTCH1 gene mutation has been identified in bicuspid aortic valve patients. We developed an in vitro model with human induced pluripotent stem cells (iPSCs) to evaluate the role of NOTCH1 in smooth muscle and endothelial cell (EC) differentiation. The iPSCs were derived from a patient with a normal tricuspid aortic valve and aorta. The NOTCH1 gene was targeted in iPSCs with the Clustered Regularly Interspaced Short Palindromic Repeats/CRISPR-associated protein 9 nuclease (Cas9) system. The NOTCH1 -/- (NOTCH1 homozygous knockout) and isogenic control iPSCs (wild type) were differentiated into neural crest stem cells (NCSCs) and into cardiovascular progenitor cells (CVPCs). The NCSCs were differentiated into smooth muscle cells (SMCs). The CVPCs were differentiated into ECs. The differentiations of SMCs and ECs were compared between NOTCH1 -/- and wild type cells. The expression of NCSC markers (SRY-related HMG-box 10 and transcription factor AP-2 alpha) was significantly lower in NOTCH1 -/- NCSCs than in wild type NCSCs. The SMCs derived from NOTCH1 -/- NCSCs showed immature morphology with smaller size and decreased expression of all SMC-specific contractile proteins. In NOTCH1 -/- CVPCs, the expression of ISL1, NKX2.5, and MYOCD was significantly lower than that in isogenic control CVPCs, indicating impaired differentiation from iPSCs to CVPCs. The NOTCH1 -/- ECs derived from CVPCs showed significantly lower expression of cluster of differentiation 105 and cluster of differentiation 31 mRNA and protein, indicating a defective differentiation process. NOTCH1 is critical in SMC and EC differentiation of iPSCs through NCSCs and CVPCs, respectively. NOTCH1 gene mutations might potentially contribute to the development of thoracic aortic aneurysms by affecting SMC differentiation in some patients with bicuspid aortic valve. Copyright © 2018 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  19. Impaired Malate and Fumarate Accumulation Due to the Mutation of the Tonoplast Dicarboxylate Transporter Has Little Effects on Stomatal Behavior.

    Science.gov (United States)

    Medeiros, David B; Barros, Kallyne A; Barros, Jessica Aline S; Omena-Garcia, Rebeca P; Arrivault, Stéphanie; Sanglard, Lílian M V P; Detmann, Kelly C; Silva, Willian Batista; Daloso, Danilo M; DaMatta, Fábio M; Nunes-Nesi, Adriano; Fernie, Alisdair R; Araújo, Wagner L

    2017-11-01

    Malate is a central metabolite involved in a multiplicity of plant metabolic pathways, being associated with mitochondrial metabolism and playing significant roles in stomatal movements. Vacuolar malate transport has been characterized at the molecular level and is performed by at least one carrier protein and two channels in Arabidopsis ( Arabidopsis thaliana ) vacuoles. The absence of the Arabidopsis tonoplast Dicarboxylate Transporter (tDT) in the tdt knockout mutant was associated previously with an impaired accumulation of malate and fumarate in leaves. Here, we investigated the consequences of this lower accumulation on stomatal behavior and photosynthetic capacity as well as its putative metabolic impacts. Neither the stomatal conductance nor the kinetic responses to dark, light, or high CO 2 were highly affected in tdt plants. In addition, we did not observe any impact on stomatal aperture following incubation with abscisic acid, malate, or citrate. Furthermore, an effect on photosynthetic capacity was not observed in the mutant lines. However, leaf mitochondrial metabolism was affected in the tdt plants. Levels of the intermediates of the tricarboxylic acid cycle were altered, and increases in both light and dark respiration were observed. We conclude that manipulation of the tonoplastic organic acid transporter impacted mitochondrial metabolism, while the overall stomatal and photosynthetic capacity were unaffected. © 2017 American Society of Plant Biologists. All Rights Reserved.

  20. Mutations in the β-Subunit of the RNA Polymerase Impair the Surface-Associated Motility and Virulence of Acinetobacter baumannii.

    Science.gov (United States)

    Pérez-Varela, María; Corral, Jordi; Vallejo, Juan Andrés; Rumbo-Feal, Soraya; Bou, Germán; Aranda, Jesús; Barbé, Jordi

    2017-08-01

    Acinetobacter baumannii is a major cause of antibiotic-resistant nosocomial infections worldwide. In this study, several rifampin-resistant spontaneous mutants obtained from the A. baumannii ATCC 17978 strain that differed in their point mutations in the rpoB gene, encoding the β-subunit of the RNA polymerase, were isolated. All the mutants harboring amino acid substitutions in position 522 or 540 of the RpoB protein were impaired in surface-associated motility and had attenuated virulence in the fertility model of Caenorhabditis elegans The transcriptional profile of these mutants included six downregulated genes encoding proteins homologous to transporters and metabolic enzymes widespread among A. baumannii clinical isolates. The construction of knockout mutants in each of the six downregulated genes revealed a significant reduction in the surface-associated motility and virulence of four of them in the A. baumannii ATCC 17978 strain, as well as in the virulent clinical isolate MAR002. Taken together, our results provide strong evidence of the connection between motility and virulence in this multiresistant nosocomial pathogen. Copyright © 2017 American Society for Microbiology.

  1. Bone structure in two adult subjects with impaired minor spliceosome function resulting from RNU4ATAC mutations causing microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1).

    Science.gov (United States)

    Krøigård, Anne Bruun; Frost, Morten; Larsen, Martin Jakob; Ousager, Lilian Bomme; Frederiksen, Anja Lisbeth

    2016-11-01

    Microcephalic osteodysplastic primordial dwarfism type 1 (MOPD1), or Taybi-Linder syndrome is characterized by distinctive skeletal dysplasia, severe intrauterine and postnatal growth retardation, microcephaly, dysmorphic features, and neurological malformations. It is an autosomal recessive disorder caused by homozygous or compound heterozygous mutations in the RNU4ATAC gene resulting in impaired function of the minor spliceosome. Here, we present the first report on bone morphology, bone density and bone microstructure in two adult MOPD1 patients and applied radiographs, dual energy X-ray absorptiometry, high-resolution peripheral quantitative computed tomography and biochemical evaluation. The MOPD1 patients presented with short stature, low BMI but normal macroscopic bone configuration. Bone mineral density was low. Compared to Danish reference data, total bone area, cortical bone area, cortical thickness, total bone density, cortical bone density, trabecular bone density and trabecular bone volume per tissue volume (BV/TV) were all low. These findings may correlate to the short stature and low body weight of the MOPD1 patients. Our findings suggest that minor spliceosome malfunction may be associated with altered bone modelling. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  2. High prevalence of impaired glucose homeostasis and myopathy in asymptomatic and oligosymptomatic 3243A>G mitochondrial DNA mutation-positive subjects

    DEFF Research Database (Denmark)

    Frederiksen, A.L.; Jeppesen, T.D.; Vissing, J.

    2009-01-01

    combinations. Consequently, it is difficult to predict the "phenotypic risk profile" of 3243A>G mutation-positive subjects. The 3243A>G mutation coexists in cells with wild-type mtDNA, a phenomenon called heteroplasmy. The marked variability in mutation loads in different tissues is the main explanation...

  3. ENU-mutagenesis mice with a non-synonymous mutation in Grin1 exhibit abnormal anxiety-like behaviors, impaired fear memory, and decreased acoustic startle response

    Science.gov (United States)

    2013-01-01

    Background The Grin1 (glutamate receptor, ionotropic, NMDA1) gene expresses a subunit of N-methyl-D-aspartate (NMDA) receptors that is considered to play an important role in excitatory neurotransmission, synaptic plasticity, and brain development. Grin1 is a candidate susceptibility gene for neuropsychiatric disorders, including schizophrenia, bipolar disorder, and attention deficit/hyperactivity disorder (ADHD). In our previous study, we examined an N-ethyl-N-nitrosourea (ENU)-generated mutant mouse strain (Grin1Rgsc174/Grin1+) that has a non-synonymous mutation in Grin1. These mutant mice showed hyperactivity, increased novelty-seeking to objects, and abnormal social interactions. Therefore, Grin1Rgsc174/Grin1+ mice may serve as a potential animal model of neuropsychiatric disorders. However, other behavioral characteristics related to these disorders, such as working memory function and sensorimotor gating, have not been fully explored in these mutant mice. In this study, to further investigate the behavioral phenotypes of Grin1Rgsc174/Grin1+ mice, we subjected them to a comprehensive battery of behavioral tests. Results There was no significant difference in nociception between Grin1Rgsc174/Grin1+ and wild-type mice. The mutants did not display any abnormalities in the Porsolt forced swim and tail suspension tests. We confirmed the previous observations that the locomotor activity of these mutant mice increased in the open field and home cage activity tests. They displayed abnormal anxiety-like behaviors in the light/dark transition and the elevated plus maze tests. Both contextual and cued fear memory were severely deficient in the fear conditioning test. The mutant mice exhibited slightly impaired working memory in the eight-arm radial maze test. The startle amplitude was markedly decreased in Grin1Rgsc174/Grin1+ mice, whereas no significant differences between genotypes were detected in the prepulse inhibition (PPI) test. The mutant mice showed no obvious

  4. Mutation for nonsyndromic mental retardation in the trans-2-enoyl-CoA reductase TER gene involved in fatty acid elongation impairs the enzyme activity and stability, leading to change in sphingolipid profile.

    Science.gov (United States)

    Abe, Kensuke; Ohno, Yusuke; Sassa, Takayuki; Taguchi, Ryo; Çalışkan, Minal; Ober, Carole; Kihara, Akio

    2013-12-20

    Very long-chain fatty acids (VLCFAs, chain length >C20) exist in tissues throughout the body and are synthesized by repetition of the fatty acid (FA) elongation cycle composed of four successive enzymatic reactions. In mammals, the TER gene is the only gene encoding trans-2-enoyl-CoA reductase, which catalyzes the fourth reaction in the FA elongation cycle. The TER P182L mutation is the pathogenic mutation for nonsyndromic mental retardation. This mutation substitutes a leucine for a proline residue at amino acid 182 in the TER enzyme. Currently, the mechanism by which the TER P182L mutation causes nonsyndromic mental retardation is unknown. To understand the effect of this mutation on the TER enzyme and VLCFA synthesis, we have biochemically characterized the TER P182L mutant enzyme using yeast and mammalian cells transfected with the TER P182L mutant gene and analyzed the FA elongation cycle in the B-lymphoblastoid cell line with the homozygous TER P182L mutation (TER(P182L/P182L) B-lymphoblastoid cell line). We have found that TER P182L mutant enzyme exhibits reduced trans-2-enoyl-CoA reductase activity and protein stability, thereby impairing VLCFA synthesis and, in turn, altering the sphingolipid profile (i.e. decreased level of C24 sphingomyelin and C24 ceramide) in the TER(P182L/P182L) B-lymphoblastoid cell line. We have also found that in addition to the TER enzyme-catalyzed fourth reaction, the third reaction in the FA elongation cycle is affected by the TER P182L mutation. These findings provide new insight into the biochemical defects associated with this genetic mutation.

  5. Carriers of loss-of-function mutations in EXT display impaired pancreatic beta-cell reserve due to smaller pancreas volume.

    Directory of Open Access Journals (Sweden)

    Sophie J Bernelot Moens

    Full Text Available Exotosin (EXT proteins are involved in the chain elongation step of heparan sulfate (HS biosynthesis, which is intricately involved in organ development. Loss of function mutations (LOF in EXT1 and EXT2 result in hereditary exostoses (HME. Interestingly, HS plays a role in pancreas development and beta-cell function, and genetic variations in EXT2 are associated with an increased risk for type 2 diabetes mellitus. We hypothesized that loss of function of EXT1 or EXT2 in subjects with hereditary multiple exostoses (HME affects pancreatic insulin secretion capacity and development. We performed an oral glucose tolerance test (OGTT followed by hyperglycemic clamps to investigate first-phase glucose-stimulated insulin secretion (GSIS in HME patients and age and gender matched non-affected relatives. Pancreas volume was assessed with magnetic resonance imaging (MRI. OGTT did not reveal significant differences in glucose disposal, but there was a markedly lower GSIS in HME subjects during hyperglycemic clamp (iAUC HME: 0.72 [0.46-1.16] vs. controls 1.53 [0.69-3.36] nmol·l-1·min-1, p<0.05. Maximal insulin response following arginine challenge was also significantly attenuated (iAUC HME: 7.14 [4.22-10.5] vs. controls 10.2 [7.91-12.70] nmol·l-1·min-1 p<0.05, indicative of an impaired beta-cell reserve. MRI revealed a significantly smaller pancreatic volume in HME subjects (HME: 72.0±15.8 vs. controls 96.5±26.0 cm3 p = 0.04. In conclusion, loss of function of EXT proteins may affect beta-cell mass and insulin secretion capacity in humans, and render subjects at a higher risk of developing type 2 diabetes when exposed to environmental risk factors.

  6. Effects of hemochromatosis and transferrin gene mutations on peripheral iron dyshomeostasis in Mild Cognitive Impairment and Alzheimer’s and Parkinson’s diseases

    Directory of Open Access Journals (Sweden)

    Stefania eMariani

    2013-08-01

    Full Text Available Deregulation of iron metabolism has been observed in patients with neurodegenerative diseases. We have carried out a molecular analysis investigating the interaction between iron specific gene variants [transferrin (TF, P589S, hemochromatosis (HFE C282Y and H63D], iron biochemical variables [iron, Tf, ceruloplasmin (Cp, Cp:Tf ratio and % of Tf saturation (% Tf-sat] Impairment (MCI, 78 Parkinson’s disease (PD patients and 139 healthy controls to investigate mechanisms of iron regulation or toxicity. No difference in genetic variant distributions between patients and controls was found in our Italian sample, but the stratification for the APOE e4 allele revealed that among the APOE e4 carriers was higher the frequency of those carriers of at least a mutated TF P589S allele. Decreased Tf in both AD and MCI and increased Cp:Tf ratio in AD vs. controls were detected. A multinomial logistic regression model revealed that increased iron and Cp:Tf ratio and being man instead of woman increased the risk of having PD, that increased values of Cp:Tf ratio corresponded to a 4-fold increase of the relative risk of having MCI, while higher Cp levels were protective for PD and MCI. Our study has some limitations: the small size of the sample, one ethnic group considered, the rarity of some alleles which prevent the statistical power of some genetic analysis. Even though they need confirmation in larger cohorts, our data suggest the hypothesis that deregulation of iron metabolism, in addition to other factors, has some effect on the PD disease risk.

  7. High prevalence of impaired glucose homeostasis and myopathy in asymptomatic and oligosymptomatic 3243A>G mitochondrial DNA mutation-positive subjects

    DEFF Research Database (Denmark)

    Frederiksen, A.L.; Jeppesen, T.D.; Vissing, J.

    2009-01-01

    controls were subjected to an oral glucose tolerance test. Twenty-six adult 3243A>G carriers with unknown myopathy status and 17 healthy controls had a maximal cycle test and a muscle biopsy performed. The mutation loads were quantified in blood and muscle biopsies and correlated to the clinical......INTRODUCTION: The point mutation of 3243A>G mtDNA is the most frequent cause of mitochondrial diabetes, often presenting as the syndrome maternally inherited diabetes and deafness (MIDD). The mutation may also cause myopathy, ataxia, strokes, ophthalmoplegia, epilepsy, and cardiomyopathy in various...... combinations. Consequently, it is difficult to predict the "phenotypic risk profile" of 3243A>G mutation-positive subjects. The 3243A>G mutation coexists in cells with wild-type mtDNA, a phenomenon called heteroplasmy. The marked variability in mutation loads in different tissues is the main explanation...

  8. De novo mutations in the motor domain of KIF1A cause cognitive impairment, spastic paraparesis, axonal neuropathy, and cerebellar atrophy

    NARCIS (Netherlands)

    Lee, Jae Ran; Srour, Myriam; Kim, Doyoun; Hamdan, Fadi F.; Lim, So Hee; Brunel-Guitton, Catherine; Décarie, Jean Claude; Rossignol, Elsa; Mitchell, Grant A.; Schreiber, Allison; Moran, Rocio; Van Haren, Keith; Richardson, Randal; Nicolai, Joost; Oberndorff, Karin M E J; Wagner, Justin D.; Boycott, Kym M.; Rahikkala, Elisa; Junna, Nella; Tyynismaa, Henna; Cuppen, Inge; Verbeek, Nienke E.; Stumpel, Connie T R M; Willemsen, Michel A.; de Munnik, Sonja A.; Rouleau, Guy A.; Kim, Eunjoon; Kamsteeg, Erik Jan; Kleefstra, Tjitske; Michaud, Jacques L.

    2015-01-01

    KIF1A is a neuron-specific motor protein that plays important roles in cargo transport along neurites. Recessive mutations in KIF1A were previously described in families with spastic paraparesis or sensory and autonomic neuropathy type-2. Here, we report 11 heterozygous de novo missense mutations

  9. A mouse genetic model for familial cholestasis caused by ATP8B1 mutations reveals perturbed bile salt homeostasis but no impairment in bile secretion

    NARCIS (Netherlands)

    Pawlikowska, Ludmila; Groen, Annemiek; Eppens, Elaine F.; Kunne, Cindy; Ottenhoff, Roelof; Looije, Norbert; Knisely, A. S.; Killeen, Nigel P.; Bull, Laura N.; Elferink, Ronald P. J. Oude; Freimer, Nelson B.

    2004-01-01

    Mutations in ATP8B1, a broadly expressed P-type ATPase, result, through unknown mechanisms, in disorders of bile secretion. These disorders vary in severity from mild and episodic to progressive with liver failure. We generated Atp8b1(G308V/G308V) mutant mice, which carry a mutation orthologous to

  10. Non-syndromic hearing impairment in India: high allelic heterogeneity among mutations in TMPRSS3, TMC1, USHIC, CDH23 and TMIE.

    Directory of Open Access Journals (Sweden)

    Aparna Ganapathy

    Full Text Available Mutations in the autosomal genes TMPRSS3, TMC1, USHIC, CDH23 and TMIE are known to cause hereditary hearing loss. To study the contribution of these genes to autosomal recessive, non-syndromic hearing loss (ARNSHL in India, we examined 374 families with the disorder to identify potential mutations. We found four mutations in TMPRSS3, eight in TMC1, ten in USHIC, eight in CDH23 and three in TMIE. Of the 33 potentially pathogenic variants identified in these genes, 23 were new and the remaining have been previously reported. Collectively, mutations in these five genes contribute to about one-tenth of ARNSHL among the families examined. New mutations detected in this study extend the allelic heterogeneity of the genes and provide several additional variants for structure-function correlation studies. These findings have implications for early DNA-based detection of deafness and genetic counseling of affected families in the Indian subcontinent.

  11. Identification and molecular modelling of a mutation in the motor head domain of myosin VIIA in a family with autosomal dominant hearing impairment (DFNA11)

    NARCIS (Netherlands)

    Luijendijk, M.W.J.; Wijk, E. van; Bischoff, A.M.L.C.; Krieger, E.; Huygen, P.L.M.; Pennings, R.J.E.; Brunner, H.G.; Cremers, C.W.R.J.; Cremers, F.P.M.; Kremer, J.M.J.

    2004-01-01

    Myosin VIIA is an unconventional myosin that has been implicated in Usher syndrome type 1B, atypical Usher syndrome, non-syndromic autosomal recessive hearing impairment (DFNB2) and autosomal dominant hearing impairment (DFNA11). Here, we present a family with non-syndromic autosomal dominant

  12. Identification and molecular modelling of a mutation in the motor head domain of myosin VIIA in a family with autosomal dominant hearing impairment (DFNA11).

    NARCIS (Netherlands)

    Luijendijk, M.W.J.; Wijk, E. van; Bischoff, A.M.L.C.; Krieger, E.; Huygen, P.L.M.; Pennings, R.J.E.; Brunner, H.G.; Cremers, C.W.R.J.; Cremers, F.P.M.; Kremer, J.M.J.

    2004-01-01

    Myosin VIIA is an unconventional myosin that has been implicated in Usher syndrome type 1B, atypical Usher syndrome, non-syndromic autosomal recessive hearing impairment (DFNB2) and autosomal dominant hearing impairment (DFNA11). Here, we present a family with non-syndromic autosomal dominant

  13. Cubilin P1297L mutation associated with hereditary megaloblastic anemia 1 causes impaired recognition of intrinsic factor-vitamin B(12) by cubilin

    DEFF Research Database (Denmark)

    Kristiansen, M; Aminoff, M; Jacobsen, Christian

    2000-01-01

    Megaloblastic anemia 1 (MGA1) is an autosomal recessive disorder caused by the selective intestinal malabsorption of intrinsic factor (IF) and vitamin B(12)/cobalamin (Cbl) in complex. Most Finnish patients with MGA1 carry the disease-specific P1297L mutation (FM1) in the IF-B(12) receptor, cubilin......-IF-Cbl in cubilin-expressing epithelial cells. In conclusion, the data presented show a substantial loss in affinity of the FM1 mutant form of the IF-Cbl binding region of cubilin. This now explains the malabsorption of Cbl and Cbl-dependent anemia in MGA1 patients with the FM1 mutation. (Blood. 2000...

  14. Missense mutations in IHH impair Indian Hedgehog signaling in C3H10T1/2 cells: Implications for brachydactyly type A1, and new targets for Hedgehog signaling.

    Science.gov (United States)

    Guo, Shengzhen; Zhou, Jian; Gao, Bo; Hu, Jianxin; Wang, Hongsheng; Meng, Junwei; Zhao, Xinzhi; Ma, Gang; Lin, Chuwen; Xiao, Yue; Tang, Wei; Zhu, Xuming; Cheah, Kathryn S E; Feng, Guoying; Chan, Danny; He, Lin

    2010-01-01

    Heterozygous missense mutations in IHH result in Brachydactyly type A1 (BDA1; OMIM 112500), a condition characterized by the shortening of digits due to hypoplasia/aplasia of the middle phalanx. Indian Hedgehog signaling regulates the proliferation and differentiation of chondrocytes and is essential for endochondral bone formation. Analyses of activated IHH signaling in C3H10T1/2 cells showed that three BDA1-associated mutations (p.E95K, p.D100E and p.E131K) severely impaired the induction of targets such as Ptch1 and Gli1. However, this was not a complete loss of function, suggesting that these mutations may affect the interaction with the receptor PTCH1 or its partners, with an impact on the induction potency. From comparative microarray expression analyses and quantitative real-time PCR, we identified three additional targets, Sostdc1, Penk1 and Igfbp5, which were also severely affected. Penk1 and Igfbp5 were confirmed to be regulated by GLI1, while the induction of Sostdc1 by IHH is independent of GLI1. SOSTDC1 is a BMP antagonist, and altered BMP signaling is known to affect digit formation. The role of Penk1 and Igfbp5 in skeletogenesis is not known. However, we have shown that both Penk1 and Igfbp5 are expressed in the interzone region of the developing joint of mouse digits, providing another link for a role for IHH signaling in the formation of the distal digits.

  15. A novel heterozygous mutation in the STAT1 SH2 domain causes chronic mucocutaneous candidiasis, atypically diverse infections, autoimmunity, and impaired cytokine regulation

    NARCIS (Netherlands)

    K. Meesilpavikkai (Kornvalee); W.A. Dik (Willem); B. Schrijver (Benjamin); N.M. Nagtzaam (Nicole); A.L. Rijswijk (Angelique); G.J.A. Driessen (Gertjan); P.J. van der Spek (Peter); P.M. van Hagen (Martin); V.A.S.H. Dalm (Virgil)

    2017-01-01

    textabstractChronic mucocutaneous candidiasis (CMC) is a primary immunodeficiency characterized by persistent or recurrent skin and mucosal surface infections with Candida species. Different gene mutations leading to CMC have been identified. These include various heterozygous gain-of-function (GOF)

  16. Patient-specific mutations impair BESTROPHIN1’s essential role in mediating Ca2+-dependent Cl- currents in human RPE

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yao [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Zhang, Yu [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Xu, Yu [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Department of Ophthalmology, Xinhua Hospital affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China; Kittredge, Alec [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Ward, Nancy [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States; Chen, Shoudeng [Molecular Imaging Center, Department of Experimental Medicine, The Fifth Affiliated Hospital of Sun Yat-sen University, Zhuhai, China; Tsang, Stephen H. [Jonas Children’s Vision Care, and Bernard and Shirlee Brown Glaucoma Laboratory, Department of Ophthalmology and Pathology & Cell Biology, Edward S. Harkness Eye Institute, New York Presbyterian Hospital/Columbia University, New York, United States; Yang, Tingting [Department of Pharmacology and Physiology, School of Medicine and Dentistry, University of Rochester, Rochester, United States

    2017-10-24

    Mutations in the human BEST1 gene lead to retinal degenerative diseases displaying progressive vision loss and even blindness. BESTROPHIN1, encoded by BEST1, is predominantly expressed in retinal pigment epithelium (RPE), but its physiological role has been a mystery for the last two decades. Using a patient-specific iPSC-based disease model and interdisciplinary approaches, we comprehensively analyzed two distinct BEST1 patient mutations, and discovered mechanistic correlations between patient clinical phenotypes, electrophysiology in their RPEs, and the structure and function of BESTROPHIN1 mutant channels. Our results revealed that the disease-causing mechanism of BEST1 mutations is centered on the indispensable role of BESTROPHIN1 in mediating the long speculated Ca2+-dependent Cl- current in RPE, and demonstrate that the pathological potential of BEST1 mutations can be evaluated and predicted with our iPSC-based ‘disease-in-a-dish’ approach. Moreover, we demonstrated that patient RPE is rescuable with viral gene supplementation, providing a proof-of-concept for curing BEST1-associated diseases.

  17. Synonymous mutations in RNASEH2A create cryptic splice sites impairing RNase H2 enzyme function in Aicardi-Goutières syndrome.

    Science.gov (United States)

    Rice, Gillian I; Reijns, Martin A M; Coffin, Stephanie R; Forte, Gabriella M A; Anderson, Beverley H; Szynkiewicz, Marcin; Gornall, Hannah; Gent, David; Leitch, Andrea; Botella, Maria P; Fazzi, Elisa; Gener, Blanca; Lagae, Lieven; Olivieri, Ivana; Orcesi, Simona; Swoboda, Kathryn J; Perrino, Fred W; Jackson, Andrew P; Crow, Yanick J

    2013-08-01

    Aicardi-Goutières syndrome is an inflammatory disorder resulting from mutations in TREX1, RNASEH2A/2B/2C, SAMHD1, or ADAR1. Here, we provide molecular, biochemical, and cellular evidence for the pathogenicity of two synonymous variants in RNASEH2A. Firstly, the c.69G>A (p.Val23Val) mutation causes the formation of a splice donor site within exon 1, resulting in an out of frame deletion at the end of exon 1, leading to reduced RNase H2 protein levels. The second mutation, c.75C>T (p.Arg25Arg), also introduces a splice donor site within exon 1, and the internal deletion of 18 amino acids. The truncated protein still forms a heterotrimeric RNase H2 complex, but lacks catalytic activity. However, as a likely result of leaky splicing, a small amount of full-length active protein is apparently produced in an individual homozygous for this mutation. Recognition of the disease causing status of these variants allows for diagnostic testing in relevant families. © 2013 WILEY PERIODICALS, INC.

  18. Impaired peroxisome proliferator-activated receptor γ function through mutation of a conserved salt bridge (R425C) in familial partial lipodystrophy

    NARCIS (Netherlands)

    Jeninga, E.H.; van Beekum, P.O; van Dijk, A.D.J.; Hamers, N.; Bonvin, A.M.J.J.; Berger, R.; Kalkhoven, E.

    2007-01-01

    The nuclear receptor peroxisome proliferator-activated receptor (PPAR) γ plays a key role in the regulation of glucose and lipid metabolism in adipocytes by regulating their differentiation, maintenance, and function. A heterozygous mutation in the PPARG gene, which changes an arginine residue at

  19. Depolarized Inactivation Overcomes Impaired Activation to Produce DRG Neuron Hyperexcitability in a Nav1.7 Mutation in a Patient with Distal Limb Pain

    NARCIS (Netherlands)

    Huang, J.; Yang, Y; Dib-Hajj, S.D.; Es, M. van; Zhao, P.; Salomon, J.; Drenth, J.P.; Waxman, S.G.

    2014-01-01

    Sodium channel Nav1.7, encoded by SCN9A, is expressed in DRG neurons and regulates their excitability. Genetic and functional studies have established a critical contribution of Nav1.7 to human pain disorders. We have now characterized a novel Nav1.7 mutation (R1279P) from a female human subject

  20. Identification of p.A684V missense mutation in the WFS1 gene as a frequent cause of autosomal dominant optic atrophy and hearing impairment

    DEFF Research Database (Denmark)

    Rendtorff, Nanna D; Lodahl, Marianne; Boulahbel, Houda

    2011-01-01

    DNA deletions were detected in muscle from one p.A684V patient analyzed. Finally, wolframin p.A684V mutant ectopically expressed in HEK cells showed reduced protein levels compared to wild-type wolframin, strongly indicating that the mutation is disease-causing. Our data support OA and SNHL...

  1. Mutations in valosin-containing protein (VCP) decrease ADP/ATP translocation across the mitochondrial membrane and impair energy metabolism in human neurons.

    Science.gov (United States)

    Ludtmann, Marthe H R; Arber, Charles; Bartolome, Fernando; de Vicente, Macarena; Preza, Elisavet; Carro, Eva; Houlden, Henry; Gandhi, Sonia; Wray, Selina; Abramov, Andrey Y

    2017-05-26

    Mutations in the gene encoding valosin-containing protein (VCP) lead to multisystem proteinopathies including frontotemporal dementia. We have previously shown that patient-derived VCP mutant fibroblasts exhibit lower mitochondrial membrane potential, uncoupled respiration, and reduced ATP levels. This study addresses the underlying basis for mitochondrial uncoupling using VCP knockdown neuroblastoma cell lines, induced pluripotent stem cells (iPSCs), and iPSC-derived cortical neurons from patients with pathogenic mutations in VCP Using fluorescent live cell imaging and respiration analysis we demonstrate a VCP mutation/knockdown-induced dysregulation in the adenine nucleotide translocase, which results in a slower rate of ADP or ATP translocation across the mitochondrial membranes. This deregulation can explain the mitochondrial uncoupling and lower ATP levels in VCP mutation-bearing neurons via reduced ADP availability for ATP synthesis. This study provides evidence for a role of adenine nucleotide translocase in the mechanism underlying altered mitochondrial function in VCP-related degeneration, and this new insight may inform efforts to better understand and manage neurodegenerative disease and other proteinopathies. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  2. A new mitochondrial point mutation in the transfer RNA(Lys) gene associated with progressive external ophthalmoplegia with impaired respiratory regulation.

    Science.gov (United States)

    Wolf, Joachim; Obermaier-Kusser, Bert; Jacobs, Martina; Milles, Cornelia; Mörl, Mario; von Pein, Harald D; Grau, Armin J; Bauer, Matthias F

    2012-05-15

    We report a novel heteroplasmic point mutation G8299A in the gene for mitochondrial tRNA(Lys) in a patient with progressive external ophthalmoplegia complicated by recurrent respiratory insufficiency. Biochemical analysis of respiratory chain complexes in muscle homogenate showed a combined complex I and IV deficiency. The transition does not represent a known neutral polymorphism and affects a position in the tRNA acceptor stem which is conserved in primates, leading to a destabilization of this functionally important domain. In vitro analysis of an essential maturation step of the tRNA transcript indicates the probable pathogenicity of this mutation. We hypothesize that there is a causal relationship between the novel G8299A transition and progressive external ophthalmoplegia with recurrent respiratory failure due to a depressed respiratory drive. Copyright © 2012 Elsevier B.V. All rights reserved.

  3. Differential Motor Neuron Impairment and Axonal Regeneration in Sporadic and Familiar Amyotrophic Lateral Sclerosis with SOD-1 Mutations: Lessons from Neurophysiology

    OpenAIRE

    Bocci, Tommaso; Pecori, Chiara; Giorli, Elisa; Briscese, Lucia; Tognazzi, Silvia; Caleo, Matteo; Sartucci, Ferdinando

    2011-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a degenerative disorder of the motor system. About 10% of cases are familial and 20% of these families have point mutations in the Cu/Zn superoxide dismutase 1 (SOD-1) gene. SOD-1 catalyses the superoxide radical (O−2) into hydrogen peroxide and molecular oxygen. The clinical neurophysiology in ALS plays a fundamental role in differential diagnosis between the familial and sporadic forms and in the assessment of its severity and progression. Sixty ALS pa...

  4. Impaired action potential initiation in GABAergic interneurons causes hyperexcitable networks in an epileptic mouse model carrying a human Na(V)1.1 mutation.

    Science.gov (United States)

    Hedrich, Ulrike B S; Liautard, Camille; Kirschenbaum, Daniel; Pofahl, Martin; Lavigne, Jennifer; Liu, Yuanyuan; Theiss, Stephan; Slotta, Johannes; Escayg, Andrew; Dihné, Marcel; Beck, Heinz; Mantegazza, Massimo; Lerche, Holger

    2014-11-05

    Mutations in SCN1A and other ion channel genes can cause different epileptic phenotypes, but the precise mechanisms underlying the development of hyperexcitable networks are largely unknown. Here, we present a multisystem analysis of an SCN1A mouse model carrying the NaV1.1-R1648H mutation, which causes febrile seizures and epilepsy in humans. We found a ubiquitous hypoexcitability of interneurons in thalamus, cortex, and hippocampus, without detectable changes in excitatory neurons. Interestingly, somatic Na(+) channels in interneurons and persistent Na(+) currents were not significantly changed. Instead, the key mechanism of interneuron dysfunction was a deficit of action potential initiation at the axon initial segment that was identified by analyzing action potential firing. This deficit increased with the duration of firing periods, suggesting that increased slow inactivation, as recorded for recombinant mutated channels, could play an important role. The deficit in interneuron firing caused reduced action potential-driven inhibition of excitatory neurons as revealed by less frequent spontaneous but not miniature IPSCs. Multiple approaches indicated increased spontaneous thalamocortical and hippocampal network activity in mutant mice, as follows: (1) more synchronous and higher-frequency firing was recorded in primary neuronal cultures plated on multielectrode arrays; (2) thalamocortical slices examined by field potential recordings revealed spontaneous activities and pathological high-frequency oscillations; and (3) multineuron Ca(2+) imaging in hippocampal slices showed increased spontaneous neuronal activity. Thus, an interneuron-specific generalized defect in action potential initiation causes multisystem disinhibition and network hyperexcitability, which can well explain the occurrence of seizures in the studied mouse model and in patients carrying this mutation. Copyright © 2014 the authors 0270-6474/14/3414874-16$15.00/0.

  5. Mutation in WDR4 impairs tRNA m(7)G46 methylation and causes a distinct form of microcephalic primordial dwarfism.

    Science.gov (United States)

    Shaheen, Ranad; Abdel-Salam, Ghada M H; Guy, Michael P; Alomar, Rana; Abdel-Hamid, Mohamed S; Afifi, Hanan H; Ismail, Samira I; Emam, Bayoumi A; Phizicky, Eric M; Alkuraya, Fowzan S

    2015-09-28

    Primordial dwarfism is a state of extreme prenatal and postnatal growth deficiency, and is characterized by marked clinical and genetic heterogeneity. Two presumably unrelated consanguineous families presented with an apparently novel form of primordial dwarfism in which severe growth deficiency is accompanied by distinct facial dysmorphism, brain malformation (microcephaly, agenesis of corpus callosum, and simplified gyration), and severe encephalopathy with seizures. Combined autozygome/exome analysis revealed a novel missense mutation in WDR4 as the likely causal variant. WDR4 is the human ortholog of the yeast Trm82, an essential component of the Trm8/Trm82 holoenzyme that effects a highly conserved and specific (m(7)G46) methylation of tRNA. The human mutation and the corresponding yeast mutation result in a significant reduction of m(7)G46 methylation of specific tRNA species, which provides a potential mechanism for primordial dwarfism associated with this lesion, since reduced m(7)G46 modification causes a growth deficiency phenotype in yeast. Our study expands the number of biological pathways underlying primordial dwarfism and adds to a growing list of human diseases linked to abnormal tRNA modification.

  6. An engineered tale-transcription factor rescues transcription of factor VII impaired by promoter mutations and enhances its endogenous expression in hepatocytes.

    Science.gov (United States)

    Barbon, Elena; Pignani, Silvia; Branchini, Alessio; Bernardi, Francesco; Pinotti, Mirko; Bovolenta, Matteo

    2016-06-24

    Tailored approaches to restore defective transcription responsible for severe diseases have been poorly explored. We tested transcription activator-like effectors fused to an activation domain (TALE-TFs) in a coagulation factor VII (FVII) deficiency model. In this model, the deficiency is caused by the -94C > G or -61T > G mutation, which abrogate the binding of Sp1 or HNF-4 transcription factors. Reporter assays in hepatoma HepG2 cells naturally expressing FVII identified a single TALE-TF (TF4) that, by targeting the region between mutations, specifically trans-activated both the variant (>100-fold) and wild-type (20-40-fold) F7 promoters. Importantly, in the genomic context of transfected HepG2 and transduced primary hepatocytes, TF4 increased F7 mRNA and protein levels (2- to 3-fold) without detectable off-target effects, even for the homologous F10 gene. The ectopic F7 expression in renal HEK293 cells was modestly affected by TF4 or by TALE-TF combinations. These results provide experimental evidence for TALE-TFs as gene-specific tools useful to counteract disease-causing promoter mutations.

  7. Differential motor neuron impairment and axonal regeneration in sporadic and familiar amyotrophic lateral sclerosis with SOD-1 mutations: lessons from neurophysiology.

    Science.gov (United States)

    Bocci, Tommaso; Pecori, Chiara; Giorli, Elisa; Briscese, Lucia; Tognazzi, Silvia; Caleo, Matteo; Sartucci, Ferdinando

    2011-01-01

    Amyotrophic Lateral Sclerosis (ALS) is a degenerative disorder of the motor system. About 10% of cases are familial and 20% of these families have point mutations in the Cu/Zn superoxide dismutase 1 (SOD-1) gene. SOD-1 catalyses the superoxide radical (O(-2)) into hydrogen peroxide and molecular oxygen. The clinical neurophysiology in ALS plays a fundamental role in differential diagnosis between the familial and sporadic forms and in the assessment of its severity and progression. Sixty ALS patients (34 males; 26 females) were enrolled in the study and examined basally (T0) and every 4 months (T1, T2, and T3). Fifteen of these patients are SOD-1 symptomatic mutation carriers (nine males, six females). We used Macro-EMG and Motor Unit Number Estimation (MUNE) in order to evaluate the neuronal loss and the re-innervation process at the onset of disease and during follow-up period. SOD-1 mutation carriers have a higher number of motor units at the moment of diagnosis when compared with the sporadic form, despite a more dramatic drop in later stages. Moreover, in familiar SOD-1 ALS there is not a specific time interval in which the axonal regeneration can balance the neuronal damage. Taken together, these results strengthen the idea of a different pathogenetic mechanism at the base of sALS and fALS.

  8. Differential Motor Neuron Impairment and Axonal Regeneration in Sporadic and Familiar Amyotrophic Lateral Sclerosis with SOD-1 Mutations: Lessons from Neurophysiology

    Directory of Open Access Journals (Sweden)

    Tommaso Bocci

    2011-12-01

    Full Text Available Amyotrophic Lateral Sclerosis (ALS is a degenerative disorder of the motor system. About 10% of cases are familial and 20% of these families have point mutations in the Cu/Zn superoxide dismutase 1 (SOD-1 gene. SOD-1 catalyses the superoxide radical (O−2 into hydrogen peroxide and molecular oxygen. The clinical neurophysiology in ALS plays a fundamental role in differential diagnosis between the familial and sporadic forms and in the assessment of its severity and progression. Sixty ALS patients (34 males; 26 females were enrolled in the study and examined basally (T0 and every 4 months (T1, T2, and T3. Fifteen of these patients are SOD-1 symptomatic mutation carriers (nine males, six females. We used Macro-EMG and Motor Unit Number Estimation (MUNE in order to evaluate the neuronal loss and the re-innervation process at the onset of disease and during follow-up period. Results and Discussion: SOD-1 mutation carriers have a higher number of motor units at the moment of diagnosis when compared with the sporadic form, despite a more dramatic drop in later stages. Moreover, in familiar SOD-1 ALS there is not a specific time interval in which the axonal regeneration can balance the neuronal damage. Taken together, these results strengthen the idea of a different pathogenetic mechanism at the base of sALS and fALS.

  9. Compound heterozygous mutations (p.Leu13Pro and p.Tyr294*) associated with factor VII deficiency cause impaired secretion through ineffective translocation and extensive intracellular degradation of factor VII.

    Science.gov (United States)

    Suzuki, Keijiro; Sugawara, Takeshi; Ishida, Yoji; Suwabe, Akira

    2013-02-01

    Congenital coagulation factor VII (FVII) deficiency is a rare coagulation disease. We investigated the molecular mechanisms of this FVII deficiency in a patient with compound heterozygous mutations. A 22-year-old Japanese female was diagnosed with asymptomatic FVII deficiency. The FVII activity and antigen were greatly reduced (activity, 13.0%; antigen, 10.8%). We analyzed the F7 gene of this patient and characterized mutant FVII proteins using in vitro expression studies. Sequence analysis revealed that the patient was compound heterozygous with a point mutation (p.Leu13Pro) in the central hydrophobic core of the signal peptides and a novel non-sense mutation (p.Tyr294*) in the catalytic domain. Expression studies revealed that mutant FVII with p.Leu13Pro (FVII13P) showed less accumulation in the cells (17.5%) and less secretion into the medium (64.8%) than wild type showed. Truncated FVII resulting from p.Tyr294* (FVII294X) was also decreased in the cells (32.0%), but was not secreted into the medium. Pulse-chase experiments revealed that both mutants were extensively degraded intracellularly compared to wild type. The majority of FVII13P cannot translocate into endoplasmic reticulum (ER). However, a small amount of FVII13P was processed normally with post-translational modifications and was secreted into the medium. The fact that FVII294X was observed only in ER suggests that it is retained in ER. Proteasome apparently plays a central role in these degradations. These findings demonstrate that both mutant FVIIs impaired secretion through ineffective translocation to and retention in ER with extensive intracellular degradation, resulting in an insufficient phenotype. Copyright © 2012 Elsevier Ltd. All rights reserved.

  10. A novel familial mutation in the PCSK1 gene that alters the oxyanion hole residue of proprotein convertase 1/3 and impairs its enzymatic activity.

    Directory of Open Access Journals (Sweden)

    Michael Wilschanski

    Full Text Available Four siblings presented with congenital diarrhea and various endocrinopathies. Exome sequencing and homozygosity mapping identified five regions, comprising 337 protein-coding genes that were shared by three affected siblings. Exome sequencing identified a novel homozygous N309K mutation in the proprotein convertase subtilisin/kexin type 1 (PCSK1 gene, encoding the neuroendocrine convertase 1 precursor (PC1/3 which was recently reported as a cause of Congenital Diarrhea Disorder (CDD. The PCSK1 mutation affected the oxyanion hole transition state-stabilizing amino acid within the active site, which is critical for appropriate proprotein maturation and enzyme activity. Unexpectedly, the N309K mutant protein exhibited normal, though slowed, prodomain removal and was secreted from both HEK293 and Neuro2A cells. However, the secreted enzyme showed no catalytic activity, and was not processed into the 66 kDa form. We conclude that the N309K enzyme is able to cleave its own propeptide but is catalytically inert against in trans substrates, and that this variant accounts for the enteric and systemic endocrinopathies seen in this large consanguineous kindred.

  11. Parkinson's disease brain mitochondria have impaired respirasome assembly, age-related increases in distribution of oxidative damage to mtDNA and no differences in heteroplasmic mtDNA mutation abundance

    Directory of Open Access Journals (Sweden)

    Keeney Paula M

    2009-09-01

    Full Text Available Abstract Background Sporadic Parkinson's disease (sPD is a nervous system-wide disease that presents with a bradykinetic movement disorder and is frequently complicated by depression and cognitive impairment. sPD likely has multiple interacting causes that include increased oxidative stress damage to mitochondrial components and reduced mitochondrial bioenergetic capacity. We analyzed mitochondria from postmortem sPD and CTL brains for evidence of oxidative damage to mitochondrial DNA (mtDNA, heteroplasmic mtDNA point mutations and levels of electron transport chain proteins. We sought to determine if sPD brains possess any mtDNA genotype-respiratory phenotype relationships. Results Treatment of sPD brain mtDNA with the mitochondrial base-excision repair enzyme 8-oxyguanosine glycosylase-1 (hOGG1 inhibited, in an age-dependent manner, qPCR amplification of overlapping ~2 kbase products; amplification of CTL brain mtDNA showed moderate sensitivity to hOGG1 not dependent on donor age. hOGG1 mRNA expression was not different between sPD and CTL brains. Heteroplasmy analysis of brain mtDNA using Surveyor nuclease® showed asymmetric distributions and levels of heteroplasmic mutations across mtDNA but no patterns that statistically distinguished sPD from CTL. sPD brain mitochondria displayed reductions of nine respirasome proteins (respiratory complexes I-V. Reduced levels of sPD brain mitochondrial complex II, III and V, but not complex I or IV proteins, correlated closely with rates of NADH-driven electron flow. mtDNA levels and PGC-1α expression did not differ between sPD and CTL brains. Conclusion PD brain mitochondria have reduced mitochondrial respiratory protein levels in complexes I-V, implying a generalized defect in respirasome assembly. These deficiencies do not appear to arise from altered point mutational burden in mtDNA or reduction of nuclear signaling for mitochondrial biogenesis, implying downstream etiologies. The origin of age

  12. Gene structure and mutations of glutaryl-coenzyme A dehydrogenase: impaired association of enzyme subunits that is due to an A421V substitution causes glutaric acidemia type I in the Amish.

    OpenAIRE

    Biery, B. J.; Stein, D. E.; Morton, D. H.; Goodman, S. I.

    1996-01-01

    The structure of the human glutaryl coenzyme A dehydrogenase (GCD) gene was determined to contain 11 exons and to span approximately 7 kb. Fibroblast DNA from 64 unrelated glutaric acidemia type I (GA1) patients was screened for mutations by PCR amplification and analysis of SSCP. Fragments with altered electrophoretic mobility were subcloned and sequenced to detect mutations that caused GA1. This report describes the structure of the GCD gene, as well as point mutations and polymorphisms fou...

  13. Identification and Structural Characterization of I84C and I84A Mutations That Are Associated with High-Level Resistance to Human Immunodeficiency Virus Protease Inhibitors and Impair Viral Replication▿

    Science.gov (United States)

    Mo, Hongmei; Parkin, Neil; Stewart, Kent D.; Lu, Liangjun; Dekhtyar, Tatyana; Kempf, Dale J.; Molla, Akhteruzzaman

    2007-01-01

    Two novel human immunodeficiency virus protease mutations, I84C and I84A, were identified in patient isolates. The mutants with I84C displayed high-level resistance (median, at least 56-fold) to nelfinavir and saquinavir, but the majority remained susceptible to lopinavir. In contrast, isolates with the I84A mutation exhibited ≥33-fold median increased levels of resistance to nelfinavir, indinavir, amprenavir, ritonavir, lopinavir, saquinavir, and atazanavir. Isolates with the I84A or I84C mutation tended to be more resistant than the isolates with the I84V mutation. Modeling of the structure of the mutant proteases indicated that the I84V, I84C, and I84A mutations all create unoccupied volume in the active site, with I84A introducing the greatest change in the accessible surface area from that of the wild-type structure. PMID:17101675

  14. Lysosomal impairment in Parkinson's disease.

    Science.gov (United States)

    Dehay, Benjamin; Martinez-Vicente, Marta; Caldwell, Guy A; Caldwell, Kim A; Yue, Zhenyue; Cookson, Mark R; Klein, Christine; Vila, Miquel; Bezard, Erwan

    2013-06-01

    Impairment of autophagy-lysosomal pathways (ALPs) is increasingly regarded as a major pathogenic event in neurodegenerative diseases, including Parkinson's disease (PD). ALP alterations are observed in sporadic PD brains and in toxic and genetic rodent models of PD-related neurodegeneration. In addition, PD-linked mutations and post-translational modifications of α-synuclein impair its own lysosomal-mediated degradation, thereby contributing to its accumulation and aggregation. Furthermore, other PD-related genes, such as leucine-rich repeat kinase-2 (LRRK2), parkin, and phosphatase and tensin homolog (PTEN)-induced putative kinase 1 (PINK1), have been mechanistically linked to alterations in ALPs. Conversely, mutations in lysosomal-related genes, such as glucocerebrosidase (GBA) and lysosomal type 5 P-type ATPase (ATP13A2), have been linked to PD. New data offer mechanistic molecular evidence for such a connection, unraveling a causal link between lysosomal impairment, α-synuclein accumulation, and neurotoxicity. First, PD-related GBA deficiency/mutations initiate a positive feedback loop in which reduced lysosomal function leads to α-synuclein accumulation, which, in turn, further decreases lysosomal GBA activity by impairing the trafficking of GBA from the endoplasmic reticulum-Golgi to lysosomes, leading to neurodegeneration. Second, PD-related mutations/deficiency in the ATP13A2 gene lead to a general lysosomal impairment characterized by lysosomal membrane instability, impaired lysosomal acidification, decreased processing of lysosomal enzymes, reduced degradation of lysosomal substrates, and diminished clearance of autophagosomes, collectively contributing to α-synuclein accumulation and cell death. According to these new findings, primary lysosomal defects could potentially account for Lewy body formation and neurodegeneration in PD, laying the groundwork for the prospective development of new neuroprotective/disease-modifying therapeutic strategies

  15. Visual Impairment

    Science.gov (United States)

    ... site Sitio para adolescentes Body Mind Sexual Health Food & Fitness Diseases & Conditions Infections Drugs & Alcohol School & Jobs Sports Expert Answers (Q&A) Staying Safe Videos for Educators Search English Español Visual Impairment KidsHealth / For Teens / Visual Impairment What's in ...

  16. Partial rescue of in vivo insulin signalling in skeletal muscle by impaired insulin clearance in heterozygous carriers of a mutation in the insulin receptor gene

    DEFF Research Database (Denmark)

    Højlund, K.; Wojtaszewski, Jørgen; Birk, Jesper Bratz

    2006-01-01

    AIMS/HYPOTHESIS: Recently we reported the coexistence of postprandial hypoglycaemia and moderate insulin resistance in heterozygous carriers of the Arg1174Gln mutation in the insulin receptor gene (INSR). Controlled studies of in vivo insulin signalling in humans with mutant INSR are unavailable,...

  17. Impaired Driving

    Science.gov (United States)

    ... Get the Facts What Works: Strategies to Increase Car Seat and Booster Seat ... narcotics. 3 That’s one percent of the 111 million self-reported episodes of alcohol-impaired driving among U.S. ...

  18. Mutation of Asp(171) and Asp(262) of the chemokine receptor CXCR4 impairs its coreceptor function for human immunodeficiency virus-1 entry and abrogates the antagonistic activity of AMD3100

    DEFF Research Database (Denmark)

    Hatse, S; Princen, K; Gerlach, L O

    2001-01-01

    by mutational analysis. We established a set of stably transfected U87.CD4 cell lines expressing different mutant forms of CXCR4 (i.e., CXCR4[WT], CXCR4[D171N], CXCR4[D262N], CXCR4[D171N,D262N], and CXCR4[H281A]), to compare the activity of the compound against mutated versus wild-type CXCR4. We found...... by substitution of Asp(171) and/or Asp(262) by neutral asparagine residue(s). Both aspartates, but most particularly Asp(262), also proved essential for the anti-HIV-1 activity of AMD3100 against the viruses NL4.3, IIIB, and HE. In contrast, substitution of His(281) by a neutral alanine potentiated...

  19. Impairment of the transition from proliferative stage to prehypertrophic stage in chondrogenic differentiation of human induced pluripotent stem cells harboring the causative mutation of achondroplasia in fibroblast growth factor receptor 3

    Directory of Open Access Journals (Sweden)

    Naohiro Horie

    2017-06-01

    Conclusions: These results suggested that chondrocyte maturation was impaired between the proliferative stage and prehypertrophic stage in the chondrocytes of ACH. The development of chemical compounds which affect the specific maturation stage of chondrocytes is expected to contribute to the ACH treatment, and FGFR3 genome-edited hiPSCs will be a valuable tool in such research studies.

  20. Physical Impairment

    Science.gov (United States)

    Trewin, Shari

    Many health conditions can lead to physical impairments that impact computer and Web access. Musculoskeletal conditions such as arthritis and cumulative trauma disorders can make movement stiff and painful. Movement disorders such as tremor, Parkinsonism and dystonia affect the ability to control movement, or to prevent unwanted movements. Often, the same underlying health condition also has sensory or cognitive effects. People with dexterity impairments may use a standard keyboard and mouse, or any of a wide range of alternative input mechanisms. Examples are given of the diverse ways that specific dexterity impairments and input mechanisms affect the fundamental actions of Web browsing. As the Web becomes increasingly sophisticated, and physically demanding, new access features at the Web browser and page level will be necessary.

  1. High incidence of GJB2 gene mutations among assortatively mating ...

    Indian Academy of Sciences (India)

    High incidence of GJB2 gene mutations among assortatively mating hearing impaired families in Kerala: future implications. Amritkumar Pavithra, Justin Margret Jeffrey, Jayasankaran Chandru, Arabandi Ramesh and C. R. Srikumari Srisailapathy. J. Genet. 93, 207–213. Table 1. Consolidated table of GJB2 mutation status ...

  2. Structural changes induced by L50P and I61T single mutations of ubiquitin affect cell cycle progression while impairing its regulatory and degradative functions in Saccharomyces cerevisiae.

    Science.gov (United States)

    Doshi, Ankita; Sharma, Mrinal; Prabha, C Ratna

    2017-06-01

    Posttranslational conjugation of ubiquitin to proteins either regulates their function directly or concentration through ubiquitination dependent degradation. High degree of conservation of ubiquitin's sequence implies structural and functional importance of the conserved residues. Ubiquitin gene of Saccharomyces cerevisiae was evolved in vitro by us to study the significance of conserved residues. Present study investigates the structural changes in the protein resulting from the single mutations UbS20F, UbA46S, UbL50P, UbI61T and their functional consequences in the SUB60 strain of S. cerevisiae. Expression of UbL50P and UbI61T decreased Cdc28 protein kinase, enhanced Fus3 levels, caused dosage dependent lethality and at sublethal level produced drastic effects on stress tolerance, protein sorting, protein degradation by ubiquitin fusion degradation pathway and by lysosomes. UbS20F and UbA46S produced insignificant effects over the cells. All four mutations of ubiquitin were incorporated into polyubiquitin. However, polyubiquitination with K63 linkage decreased significantly in cells expressing UbL50P and UbI61T. Structural studies on UbL50P and UbI61T revealed distorted structure with greatly reduced α-helical and elevated β-sheet contents, while UbS20F and UbA46S show mild structural alterations. Our results on functional efficacy of ubiquitin in relation to structural integrity may be useful for designing inhibitors to investigate and modulate eukaryotic cellular dynamics. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Association between loss-of-function mutations in the filaggrin gene and self-reported food allergy and alcohol sensitivity

    DEFF Research Database (Denmark)

    Linneberg, Allan René; Fenger, Runa V; Husemoen, Lise Lotte Nystrup

    2013-01-01

    Loss-of-function mutations of the filaggrin (FLG) gene cause an impaired skin barrier and increase the risk of atopic dermatitis. Interestingly, FLG mutations have also been found to be associated with a high risk of peanut allergy.......Loss-of-function mutations of the filaggrin (FLG) gene cause an impaired skin barrier and increase the risk of atopic dermatitis. Interestingly, FLG mutations have also been found to be associated with a high risk of peanut allergy....

  4. Audiometric Characteristics of a Dutch DFNA10 Family With Mid-Frequency Hearing Impairment

    NARCIS (Netherlands)

    Beelen, E. van; Oonk, A.M.M.; Leijendeckers, J.M.; Hoefsloot, E.H.; Pennings, R.J.E.; Feenstra, I.; Dieker, H.J.; Huygen, P.L.M.; Snik, A.F.M.; Kremer, H.; Kunst, H.P.M.

    2016-01-01

    OBJECTIVES: Mutations in EYA4 can cause nonsyndromic autosomal dominant sensorineural hearing impairment (DFNA10) or a syndromic variant with hearing impairment and dilated cardiomyopathy. A mutation in EYA4 was found in a Dutch family, causing DFNA10. This study is focused on characterizing the

  5. External ear anomalies and hearing impairment in Noonan Syndrome.

    Science.gov (United States)

    van Trier, Dorothée C; van Nierop, Josephine; Draaisma, Jos M Th; van der Burgt, Ineke; Kunst, Henricus; Croonen, Ellen A; Admiraal, Ronald J C

    2015-06-01

    This is the first cohort in which hearing impairment and external ear anomalies in Noonan Syndrome are described extensively. Retrospective analysis of the otorhinolaryngological and clinical genetic data from 97 Noonan Syndrome (NS) patients. Forty-four NS patients were seen by an otorhinolaryngologist for the analysis of hearing impairment. In our cohort 80 of the 97 patients were genetically tested. In 71 of these mutations were found: in 48 patients a mutation in PTPN11, in 10 patients in SOS1, in 5 patients in SHOC2, in 5 patients in RAF1, in 1 patient in MAP2K2, in 1 patient in KRAS and in 1 patient in A2ML1. External ear anomalies were reported in 75 NS patients (77%). In 69 patients the ears were low-set, 28 patients had posteriorly rotated ears, 14 patients showed protruding ears and 18 had thickened helices. Hearing impairment was detected in 34 NS patients. Nine patients had sensorineural hearing impairment, two a permanent conductive hearing impairment, two other patients had mixed hearing impairment and 20 patients had conductive hearing impairment in the past, caused by otitis media with effusion. Their temporary conductive hearing impairment resolved between the ages of 2 and 18 years. Sensorineural hearing impairment varied between mild high-frequency hearing impairment and profound (uni- and bilateral) hearing impairment and was progressive in three patients. Four NS patients received cochlear implants for their severe sensorineural hearing impairment. The cohort is small for genotype-phenotype correlations, but sensorineural hearing impairment, especially the bilateral severe hearing impairment, was only seen in patients with a PTPN11 mutation. NS is characterized by dysmorphic external ear anomalies and both sensorineural and conductive hearing impairment. Audiological examinations are recommended in all patients with Noonan Syndrome. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  6. New mutations affecting induced mutagenesis in yeast.

    Science.gov (United States)

    Lawrence, C W; Krauss, B R; Christensen, R B

    1985-01-01

    Previously isolated mutations in baker's yeast, Saccharomyces cerevisiae, that impair induced mutagenesis were all identified with the aid of tests that either exclusively or predominantly detect base-pair substitutions. To avoid this bias, we have screened 11 366 potentially mutant clones for UV-induced reversion of the frameshift allele, his4-38, and have identified 10 mutants that give much reduced yields of revertants. Complementation and recombination tests show that 6 of these carry mutations at the previously known REV1, REV1 and REV3 loci, while the remaining 4 define 3 new genes, REV4 (2 mutations), REV5 and REV6. The rev4 mutations are readily suppressed in many genetic backgrounds and, like the rev5 mutation, impart only a limited deficiency for induced mutagenesis: it is likely, therefore that the REV4+ and REV5+ gene functions are only remotely concerned with this process. The rev6 mutants have a more general deficiency, however, as well as marked sensitivity to UV and an increased spontaneous mutation rate, properties that suggest the REV6 gene is directly involved in mutation induction. The REV5 gene is located about 1 cM proximal to CYC1 on chromosome X.

  7. Impaired folding and subunit assembly as disease mechanism

    DEFF Research Database (Denmark)

    Bross, P; Andresen, B S; Gregersen, N

    1998-01-01

    folding is a common effect of missense mutations occurring in genetic diseases, (ii) increasing the level of available chaperones may augment the level of functional mutant protein in vivo, and (iii) one mutation may have multiple effects. The interplay between the chaperones assisting folding......Rapid progress in DNA technology has entailed the possibility of readily detecting mutations in disease genes. In contrast to this, techniques to characterize the effects of mutations are still very time consuming. It has turned out that many of the mutations detected in disease genes are missense...... mutations. Characterization of the effect of these mutations is particularly important in order to establish that they are disease causing and to estimate their severity. We use the experiences with investigation of medium-chain acyl-CoA dehydrogenase deficiency as an example to illustrate that (i) impaired...

  8. Common Variable Immunodeficiency Caused by FANC Mutations.

    Science.gov (United States)

    Sekinaka, Yujin; Mitsuiki, Noriko; Imai, Kohsuke; Yabe, Miharu; Yabe, Hiromasa; Mitsui-Sekinaka, Kanako; Honma, Kenichi; Takagi, Masatoshi; Arai, Ayako; Yoshida, Kenichi; Okuno, Yusuke; Shiraishi, Yuichi; Chiba, Kenichi; Tanaka, Hiroko; Miyano, Satoru; Muramatsu, Hideki; Kojima, Seiji; Hira, Asuka; Takata, Minoru; Ohara, Osamu; Ogawa, Seishi; Morio, Tomohiro; Nonoyama, Shigeaki

    2017-07-01

    Common variable immunodeficiency (CVID) is the most common adult-onset primary antibody deficiency disease due to various causative genes. Several genes, which are known to be the cause of different diseases, have recently been reported as the cause of CVID in patients by performing whole exome sequencing (WES) analysis. Here, we found FANC gene mutations as a cause of adult-onset CVID in two patients. B cells were absent and CD4 + T cells were skewed toward CD45RO + memory T cells. T-cell receptor excision circles (TRECs) and signal joint kappa-deleting recombination excision circles (sjKRECs) were undetectable in both patients. Both patients had no anemia, neutropenia, or thrombocytopenia. Using WES, we identified compound heterozygous mutations of FANCE in one patient and homozygous mutation of FANCA in another patient. The impaired function of FANC protein complex was confirmed by a monoubiquitination assay and by chromosome fragility test. We then performed several immunological evaluations including quantitative lymphocyte analysis and TRECs/sjKRECs analysis for 32 individuals with Fanconi anemia (FA). In total, 22 FA patients (68.8%) were found to have immunological abnormalities, suggesting that such immunological findings may be common in FA patients. These data indicate that FANC mutations are involved in impaired lymphogenesis probably by the accumulation of DNA replication stress, leading to CVID. It is important to diagnose FA because it drastically changes clinical management. We propose that FANC mutations can cause isolated immunodeficiency in addition to bone marrow failure and malignancy.

  9. Neurocognitive Profiles in Duchenne Muscular Dystrophy and Gene Mutation Site

    Science.gov (United States)

    D’Angelo, Maria Grazia; Lorusso, Maria Luisa; Civati, Federica; Comi, Giacomo Pietro; Magri, Francesca; Del Bo, Roberto; Guglieri, Michela; Molteni, Massimo; Turconi, Anna Carla; Bresolin, Nereo

    2011-01-01

    The presence of nonprogressive cognitive impairment is recognized as a common feature in a substantial proportion of patients with Duchenne muscular dystrophy. To investigate the possible role of mutations along the dystrophin gene affecting different brain dystrophin isoforms and specific cognitive profiles, 42 school-age children affected with Duchenne muscular dystrophy, subdivided according to sites of mutations along the dystrophin gene, underwent a battery of tests tapping a wide range of intellectual, linguistic, and neuropsychologic functions. Full-scale intelligence quotient was approximately 1 S.D. below the population average in the whole group of dystrophic children. Patients with Duchenne muscular dystrophy and mutations located in the distal portion of the dystrophin gene (involving the 140-kDa brain protein isoform, called Dp140) were generally more severely affected and expressed different patterns of strengths and impairments, compared with patients with Duchenne muscular dystrophy and mutations located in the proximal portion of the dystrophin gene (not involving Dp140). Patients with Duchenne muscular dystrophy and distal mutations demonstrated specific impairments in visuospatial functions and visual memory (which seemed intact in proximally mutated patients) and greater impairment in syntactic processing. PMID:22000308

  10. Germline cytotoxic lymphocytes defective mutations in Chinese patients with lymphoma.

    Science.gov (United States)

    Chen, Xue; Zhang, Yang; Wang, Fang; Wang, Mangju; Teng, Wen; Lin, Yuehui; Han, Xiangping; Jin, Fangyuan; Xu, Yuanli; Cao, Panxiang; Fang, Jiancheng; Zhu, Ping; Tong, Chunrong; Liu, Hongxing

    2017-11-01

    Certain patients with lymphoma may harbor mutations in perforin 1 (PRF1), unc-13 homolog D (UNC13D), syntaxin 11 (STX11), STXBP2 (syntaxin binding protein 2) or SH2 domain containing 1A (SH2D1A), which causes functional defects of cytotoxic lymphocytes. Data regarding the association between genetic defects and the development of lymphoma in Chinese patients are limited to date. In the present study, 90 patients with lymphoma were analyzed for UNC13D, PRF1, STXBP2, STX11, SH2D1A and X-linked inhibitor of apoptosis. Mutations were observed in 24 (26.67%) patients; 16 patients exhibited mutations in UNC13D, 7 exhibited PRF1 mutations, and 1 exhibited monoallelic mutation in STX11. UNC13D c.2588G>A/p.G863D mutation was detected in 9 patients (10.00%) and in 4/210 controls (1.90%). This mutation was predicted to be pathogenic and it predominantly existed in the Chinese population. These findings suggest that impaired cytotoxic machinery may represent a predisposing factor for the development of lymphoma. Furthermore, these data describe a distinct mutation spectrum in Chinese patients with lymphoma, whereby UNC13D is the most frequently mutated gene. In addition, these findings suggest UNC13D c.2588G>A mutation is a founder mutation in Chinese patients.

  11. Deletion mutations of bacteriophage

    International Nuclear Information System (INIS)

    Ryo, Yeikou

    1975-01-01

    Resolution of mutation mechanism with structural changes of DNA was discussed through the studies using bacteriophage lambda. One of deletion mutations inductions of phage lambda is the irradiation of ultraviolet ray. It is not clear if the inductions are caused by errors in reparation of ultraviolet-induced damage or by the activation of int gene. Because the effective site of int gene lies within the regions unnecessary for existing, it is considered that int gene is connected to deletion mutations induction. A certain system using prophage complementarity enables to detect deletion mutations at essential hereditary sites and to solve the relations of deletion mutations with other recombination system, DNA reproduction and repairment system. Duplication and multiplication of hereditary elements were discussed. If lambda deletion mutations of the system, which can control recombination, reproduction and repairment of added DNA, are constructed, mutations mechanism with great changes of DNA structure can be solved by phage lambda. (Ichikawa, K.)

  12. Cortical visual impairment

    OpenAIRE

    Koželj, Urša

    2013-01-01

    In this thesis we discuss cortical visual impairment, diagnosis that is in the developed world in first place, since 20 percent of children with blindness or low vision are diagnosed with it. The objectives of the thesis are to define cortical visual impairment and the definition of characters suggestive of the cortical visual impairment as well as to search for causes that affect the growing diagnosis of cortical visual impairment. There are a lot of signs of cortical visual impairment. ...

  13. Better plants through mutations

    International Nuclear Information System (INIS)

    1988-01-01

    This is a public relations film describing problems associated with the genetic improvement of crop plants through induced mutations. Mutations are the ultimate source of genetic variation in plants. Mutation induction is now established as a practical tool in plant breeding. The Joint FAO/IAEA Division and the IAEA's laboratory at Seibersdorf have supported research and practical implementation of mutation breeding of both seed propagated and vegetatively propagated plants. Plant biotechnology based on in vitro culture and recombinant DNA technology will make a further significant contribution to plant breeding

  14. Association between nucleotide mutation of eNOS gene and serum ...

    African Journals Online (AJOL)

    Galaxy

    2013-05-15

    May 15, 2013 ... spasm among Japanese (Nakayama et al., 1999; Casas et al., 2006). It is believed that these mutations might result in altered NO metabolism and impaired .... ship between T-786C mutation of eNOS gene and CAD specifically in the Iranian population. To our knowledge, this polymorphism has never been ...

  15. Mutation and premating isolation

    Science.gov (United States)

    Woodruff, R. C.; Thompson, J. N. Jr

    2002-01-01

    While premating isolation might be traceable to different genetic mechanisms in different species, evidence supports the idea that as few as one or two genes may often be sufficient to initiate isolation. Thus, new mutation can theoretically play a key role in the process. But it has long been thought that a new isolation mutation would fail, because there would be no other individuals for the isolation-mutation-carrier to mate with. We now realize that premeiotic mutations are very common and will yield a cluster of progeny carrying the same new mutant allele. In this paper, we discuss the evidence for genetically simple premating isolation barriers and the role that clusters of an isolation mutation may play in initiating allopatric, and even sympatric, species divisions.

  16. Mild Cognitive Impairment (MCI)

    Science.gov (United States)

    Mild cognitive impairment (MCI) Overview Mild cognitive impairment (MCI) is an intermediate stage between the expected cognitive decline of normal aging and the more-serious decline of dementia. It ...

  17. Adapting for Impaired Patrons.

    Science.gov (United States)

    Schuyler, Michael

    1999-01-01

    Describes how a library, with an MCI Corporation grant, approached the process of setting up computers for the visually impaired. Discusses preparations, which included hiring a visually-impaired user as a consultant and contacting the VIP (Visually Impaired Persons) group; equipment; problems with the graphical user interface; and training.…

  18. Mitochondrial phenylalanyl-tRNA synthetase mutations underlie fatal infantile Alpers encephalopathy

    DEFF Research Database (Denmark)

    Elo, Jenni M; Yadavalli, Srujana S; Euro, Liliya

    2012-01-01

    was impaired. Our results imply that the three FARS2 mutations directly impair aminoacylation function and stability of mtPheRS, leading to a decrease in overall tRNA charging capacity. This study establishes a new genetic cause of infantile mitochondrial Alpers encephalopathy and reports a new mitochondrial...

  19. Memory Impairment in Children with Language Impairment

    Science.gov (United States)

    Baird, Gillian; Dworzynski, Katharina; Slonims, Vicky; Simonoff, Emily

    2010-01-01

    Aim: The aim of this study was to assess whether any memory impairment co-occurring with language impairment is global, affecting both verbal and visual domains, or domain specific. Method: Visual and verbal memory, learning, and processing speed were assessed in children aged 6 years to 16 years 11 months (mean 9y 9m, SD 2y 6mo) with current,…

  20. Genetic Mutations in Cancer

    Science.gov (United States)

    Many different types of genetic mutations are found in cancer cells. This infographic outlines certain types of alterations that are present in cancer, such as missense, nonsense, frameshift, and chromosome rearrangements.

  1. AIP mutations and gigantism.

    Science.gov (United States)

    Rostomyan, Liliya; Potorac, Iulia; Beckers, Pablo; Daly, Adrian F; Beckers, Albert

    2017-06-01

    AIP mutations are rare in sporadic acromegaly but they are seen at a higher frequency among certain specific populations of pituitary adenoma patients (pituitary gigantism cases, familial isolated pituitary adenoma (FIPA) kindreds, and patients with macroadenomas who are diagnosed ≤30 years). AIP mutations are most prevalent in patients with pituitary gigantism (29% of this group were found to have mutations in AIP gene). These data support targeted genetic screening for AIP mutations/deletions in these groups of pituitary adenoma patients. Earlier diagnosis of AIP-related acromegaly-gigantism cases enables timely clinical evaluation and treatment, thereby improving outcomes in terms of excessive linear growth and acromegaly comorbidities. Copyright © 2017 Elsevier Masson SAS. All rights reserved.

  2. Mutation breeding in peas

    Energy Technology Data Exchange (ETDEWEB)

    Jaranowski, J [Institute of Genetics and Plant Breeding, Academy of Agriculture, Poznan (Poland); Micke, A [Joint FAO/IAEA Division of Isotope and Radiation Applications of Atomic Energy for Food and Agricultural Development, International Atomic Energy Agency, Vienna (Austria)

    1985-02-01

    The pea as an ancient crop plant still today has wide uses and is an import source of food protein. It is also an important object for genetic studies and as such has been widely used in mutation induction experiments. However, in comparison with cereals this ancient crop plant (like several other grain legumes) has gained relatively little from advances in breeding. The review focuses on the prospects of genetic improvement of pea by induced mutations, discusses principles and gives methodological information. (author)

  3. Mutation breeding in peas

    International Nuclear Information System (INIS)

    Jaranowski, J.; Micke, A.

    1985-01-01

    The pea as an ancient crop plant still today has wide uses and is an import source of food protein. It is also an important object for genetic studies and as such has been widely used in mutation induction experiments. However, in comparison with cereals this ancient crop plant (like several other grain legumes) has gained relatively little from advances in breeding. The review focuses on the prospects of genetic improvement of pea by induced mutations, discusses principles and gives methodological information. (author)

  4. [FANCA gene mutation analysis in Fanconi anemia patients].

    Science.gov (United States)

    Chen, Fei; Peng, Guang-Jie; Zhang, Kejian; Hu, Qun; Zhang, Liu-Qing; Liu, Ai-Guo

    2005-10-01

    To screen the FANCA gene mutation and explore the FANCA protein function in Fanconi anemia (FA) patients. FANCA protein expression and its interaction with FANCF were analyzed using Western blot and immunoprecipitation in 3 cases of FA-A. Genomic DNA was used for MLPA analysis followed by sequencing. FANCA protein was undetectable and FANCA and FANCF protein interaction was impaired in these 3 cases of FA-A. Each case of FA-A contained biallelic pathogenic mutations in FANCA gene. No functional FANCA protein was found in these 3 cases of FA-A, and intragenic deletion, frame shift and splice site mutation were the major pathogenic mutations found in FANCA gene.

  5. Mutator activity in Schizophyllum commune

    Energy Technology Data Exchange (ETDEWEB)

    Shneyour, Y.; Koltin, Y. (Tel Aviv Univ. (Israel). Dept. of Microbiology)

    1983-01-01

    A strain with an elevated level of spontaneous mutations and an especially high rate of reversion at a specific locus (pab/sup -/) was identified. The mutator trait is recessive. UV sensitivity and the absence of a UV-specific endonucleolytic activity were associated with the enhancement of the mutation rate in mutator strains. The endonuclease associated with the regulation of the mutation rate also acted on single-stranded DNA. The molecular weight of this enzyme is about 38,000 daltons.

  6. Autosomal recessive progressive myoclonus epilepsy due to impaired ceramide synthesis.

    Science.gov (United States)

    Ferlazzo, Edoardo; Striano, Pasquale; Italiano, Domenico; Calarese, Tiziana; Gasparini, Sara; Vanni, Nicola; Fruscione, Floriana; Genton, Pierre; Zara, Federico

    2016-09-01

    Autosomal recessive progressive myoclonus epilepsy due to impaired ceramide synthesis is an extremely rare condition, so far reported in a single family of Algerian origin presenting an unusual, severe form of progressive myoclonus epilepsy characterized by myoclonus, generalized tonic-clonic seizures and moderate to severe cognitive impairment, with probable autosomal recessive inheritance. Disease onset was between 6 and 16 years of age. Genetic study allowed to identify a homozygous nonsynonymous mutation in CERS1, the gene encoding ceramide synthase 1, a transmembrane protein of the endoplasmic reticulum (ER), catalyzes the biosynthesis of C18-ceramides. The mutation decreased C18-ceramide levels. In addition, downregulation of CerS1 in neuroblastoma cell line showed activation of ER stress response and induction of proapoptotic pathways. This observation demonstrates that impairment of ceramide biosynthesis underlies neurodegeneration in humans.

  7. Are There Mutator Polymerases?

    Directory of Open Access Journals (Sweden)

    Miguel Garcia-Diaz

    2003-01-01

    Full Text Available DNA polymerases are involved in different cellular events, including genome replication and DNA repair. In the last few years, a large number of novel DNA polymerases have been discovered, and the biochemical analysis of their properties has revealed a long list of intriguing features. Some of these polymerases have a very low fidelity and have been suggested to play mutator roles in different processes, like translesion synthesis or somatic hypermutation. The current view of these processes is reviewed, and the current understanding of DNA polymerases and their role as mutator enzymes is discussed.

  8. MUTATIONS IN CALMODULIN GENES

    DEFF Research Database (Denmark)

    2013-01-01

    The present invention relates to an isolated polynucleotide encoding at least a part of calmodulin and an isolated polypeptide comprising at least a part of a calmodulin protein, wherein the polynucleotide and the polypeptide comprise at least one mutation associated with a cardiac disorder. The ...... the binding of calmodulin to ryanodine receptor 2 and use of such compound in a treatment of an individual having a cardiac disorder. The invention further provides a kit that can be used to detect specific mutations in calmodulin encoding genes....

  9. Criteria for driver impairment

    NARCIS (Netherlands)

    Brookhuis, K.A.; De Waard, D.; Fairclough, S.H

    2003-01-01

    Most traffic accidents can be attributed to driver impairment, e.g. inattention, fatigue, intoxication, etc. It is now technically feasible to monitor and diagnose driver behaviour with respect to impairment with the aid of a limited number of in-vehicle sensors. However, a valid framework for the

  10. Molecular and biochemical characterization of a unique mutation in CCS, the human copper chaperone to superoxide dismutase

    DEFF Research Database (Denmark)

    Huppke, Peter; Brendel, Cornelia; Korenke, Georg Christoph

    2012-01-01

    chaperone mutations have been described to date. We describe a child from a consanguineous family who inherited homozygous mutations in the SLC33A1, encoding an acetyl CoA transporter, and in CCS, encoding the Cu chaperone for superoxide dismutase. The CCS mutation, p.Arg163Trp, predicts substitution...... of a highly conserved arginine residue at position 163, with tryptophan in domain II of CCS, which interacts directly with superoxide dismutase 1 (SOD1). Biochemical analyses of the patient's fibroblasts, mammalian cell transfections, immunoprecipitation assays, and Lys7Δ (CCS homolog) yeast complementation...... support the pathogenicity of the mutation. Expression of CCS was reduced and binding of CCS to SOD1 impaired. As a result, this mutation causes reduced SOD1 activity and may impair other mechanisms important for normal Cu homeostasis. CCS-Arg163Trp represents the primary example of a human mutation...

  11. Hearing impairment in genotyped Wolfram syndrome patients.

    Science.gov (United States)

    Plantinga, Rutger F; Pennings, Ronald J E; Huygen, Patrick L M; Bruno, Rocco; Eller, Philipp; Barrett, Timothy G; Vialettes, Bernard; Paquis-Fluklinger, Veronique; Lombardo, Fortunato; Cremers, Cor W R J

    2008-07-01

    Wolfram syndrome is a progressive neurodegenerative syndrome characterized by the features "DIDMOAD" (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness). We sought to study the audiometric data of genotyped Wolfram syndrome patients with sensorineural hearing impairment. Pure tone threshold data of 23 Wolfram syndrome patients were used for cross-sectional analysis in subgroups (age less than 16 years or between 19 and 25 years, gender, and origin). All subgroups, with 1 exception, showed a fairly similar type of hearing impairment with, on average, thresholds of about 25 dB (range, 0 to 65 dB) at 0.25 to 1 kHz, gently sloping downward to about 60 dB (range, 25 to 95 dB) at 8 kHz. The subgroup of Dutch women, which was excluded from the calculations of the average hearing thresholds, showed a higher degree of hearing impairment. Only the latter subgroup showed progression; however, contrary to the previous longitudinal analysis, progression was not significant in the present cross-sectional analysis, presumably because of the high degree of cross-subject variability. This unique collection of audiometric data from genotyped Wolfram syndrome patients shows no substantial progression in sensorineural hearing impairment with advancing age, no relation to the types of WFS1 mutations identified, and, with exclusion of the subgroup of Dutch female patients, no significant sex-related differences.

  12. Leber's hereditary optic neuropathy is associated with mitochondrial ND1 T3394C mutation

    International Nuclear Information System (INIS)

    Liang, Min; Guan, Minqiang; Zhao, Fuxing; Zhou, Xiangtian; Yuan, Meixia; Tong, Yi; Yang, Li; Wei, Qi-Ping; Sun, Yan-Hong; Lu, Fan; Qu, Jia

    2009-01-01

    We report here the clinical, genetic and molecular characterization of four Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age-of-onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T3394C (Y30H) mutation, which localized at a highly conserved tyrosine at position 30 of ND1, and distinct sets of mtDNA polymorphisms belonging to haplogroups D4b and M9a. The occurrence of T3394C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. However, there was the absence of functionally significant mtDNA mutations in these four Chinese pedigrees carrying the T3394C mutation. Therefore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic expression of the LHON-associated T3394C mutation.

  13. Leber's hereditary optic neuropathy is associated with mitochondrial ND6 T14502C mutation

    International Nuclear Information System (INIS)

    Zhao, Fuxin; Guan, Minqiang; Zhou, Xiangtian; Yuan, Meixia; Liang, Ming; Liu, Qi; Liu, Yan; Zhang, Yongmei; Yang, Li; Tong, Yi; Wei, Qi-Ping; Sun, Yan-Hong; Qu, Jia

    2009-01-01

    We report here the clinical, genetic, and molecular characterization of three Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age of onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T14502C (I58V) mutation, which localized at a highly conserved isoleucine at position 58 of ND6, and distinct sets of mtDNA polymorphisms belonging to haplogroups M10a, F1a1, and H2. The occurrence of T14502C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Here, mtDNA variants I187T in the ND1, A122V in CO1, S99A in the A6, and V254I in CO3 exhibited an evolutionary conservation, indicating a potential modifying role in the development of visual impairment associated with T14502C mutation in those families. Furthermore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic manifestation of the LHON-associated T14502C mutation in these Chinese families.

  14. 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.

  15. A Novel Mutation in ERCC8 Gene Causing Cockayne Syndrome

    Directory of Open Access Journals (Sweden)

    Maryam Taghdiri

    2017-08-01

    Full Text Available Cockayne syndrome (CS is a rare autosomal recessive multisystem disorder characterized by impaired neurological and sensory functions, cachectic dwarfism, microcephaly, and photosensitivity. This syndrome shows a variable age of onset and rate of progression, and its phenotypic spectrum include a wide range of severity. Due to the progressive nature of this disorder, diagnosis can be more important when additional signs and symptoms appear gradually and become steadily worse over time. Therefore, mutation analysis of genes involved in CS pathogenesis can be helpful to confirm the suspected clinical diagnosis. Here, we report a novel mutation in ERCC8 gene in a 16-year-old boy who suffers from poor weight gain, short stature, microcephaly, intellectual disability, and photosensitivity. The patient was born to consanguineous family with no previous documented disease in his parents. To identify disease-causing mutation in the patient, whole exome sequencing utilizing next-generation sequencing on an Illumina HiSeq 2000 platform was performed. Results revealed a novel homozygote mutation in ERCC8 gene (NM_000082: exon 11, c.1122G>C in our patient. Another gene (ERCC6, which is also involved in CS did not have any disease-causing mutations in the proband. The new identified mutation was then confirmed by Sanger sequencing in the proband, his parents, and extended family members, confirming co-segregation with the disease. In addition, different bioinformatics programs which included MutationTaster, I-Mutant v2.0, NNSplice, Combined Annotation Dependent Depletion, The PhastCons, Genomic Evolutationary Rate Profiling conservation score, and T-Coffee Multiple Sequence Alignment predicted the pathogenicity of the mutation. Our study identified a rare novel mutation in ERCC8 gene and help to provide accurate genetic counseling and prenatal diagnosis to minimize new affected individuals in this family.

  16. A Novel Mutation in ERCC8 Gene Causing Cockayne Syndrome.

    Science.gov (United States)

    Taghdiri, Maryam; Dastsooz, Hassan; Fardaei, Majid; Mohammadi, Sanaz; Farazi Fard, Mohammad Ali; Faghihi, Mohammad Ali

    2017-01-01

    Cockayne syndrome (CS) is a rare autosomal recessive multisystem disorder characterized by impaired neurological and sensory functions, cachectic dwarfism, microcephaly, and photosensitivity. This syndrome shows a variable age of onset and rate of progression, and its phenotypic spectrum include a wide range of severity. Due to the progressive nature of this disorder, diagnosis can be more important when additional signs and symptoms appear gradually and become steadily worse over time. Therefore, mutation analysis of genes involved in CS pathogenesis can be helpful to confirm the suspected clinical diagnosis. Here, we report a novel mutation in ERCC8 gene in a 16-year-old boy who suffers from poor weight gain, short stature, microcephaly, intellectual disability, and photosensitivity. The patient was born to consanguineous family with no previous documented disease in his parents. To identify disease-causing mutation in the patient, whole exome sequencing utilizing next-generation sequencing on an Illumina HiSeq 2000 platform was performed. Results revealed a novel homozygote mutation in ERCC8 gene (NM_000082: exon 11, c.1122G>C) in our patient. Another gene ( ERCC6 ), which is also involved in CS did not have any disease-causing mutations in the proband. The new identified mutation was then confirmed by Sanger sequencing in the proband, his parents, and extended family members, confirming co-segregation with the disease. In addition, different bioinformatics programs which included MutationTaster, I-Mutant v2.0, NNSplice, Combined Annotation Dependent Depletion, The PhastCons, Genomic Evolutationary Rate Profiling conservation score, and T-Coffee Multiple Sequence Alignment predicted the pathogenicity of the mutation. Our study identified a rare novel mutation in ERCC8 gene and help to provide accurate genetic counseling and prenatal diagnosis to minimize new affected individuals in this family.

  17. Mutation, somatic mutation and diseases of man

    International Nuclear Information System (INIS)

    Burnet, F.M.

    1976-01-01

    The relevance of the intrinsic mutagenesis for the evolution process, genetic diseases and the process of aging is exemplified. The fundamental reaction is the function of the DNA and the DNA-enzymes like the DNA-polymerases in replication, repair, and transcription. These defects are responsible for the mutation frequency and the genetic drift in the evolution process. They cause genetic diseases like Xeroderma pigmentosum which is described here in detail. The accumulation of structural and functional mistakes leads to diseases of old age, for example to autoimmune diseases and immune suppression. There is a proportionality between the duration of life and the frequency of mistakes in the enzymatic repair system. No possibility of prophylaxis or therapy is seen. Methods for prognosis could be developed. (AJ) [de

  18. Prevalence of mutations and functional analyses of melanocortin 4 receptor variants identified among 750 men with juvenile-onset obesity

    DEFF Research Database (Denmark)

    Larsen, Lesli H; Echwald, Søren Morgenthaler; Sørensen, Thorkild I A

    2005-01-01

    )) for mutations in MC4R. A total of 14 different mutations were identified of which two, Ala219Val and Leu325Phe, were novel variants. The variant receptor, Leu325Phe, was unable to bind [Nle4,d-Phe7]-alphaMSH, whereas the Ala219Val variant showed a significantly impaired melanotan II induction of cAMP, compared...

  19. Leber's hereditary optic neuropathy is associated with the mitochondrial ND4 G11696A mutation in five Chinese families

    International Nuclear Information System (INIS)

    Zhou Xiangtian; Wei Qiping; Yang Li; Tong Yi; Zhao Fuxin; Lu Chunjie; Qian Yaping; Sun Yanghong; Lu Fan; Qu Jia; Guan Minxin

    2006-01-01

    We report here the clinical, genetic, and molecular characterization of five Chinese families with Leber's hereditary optic neuropathy (LHON). Clinical and genetic evaluations revealed the variable severity and age-of-onset in visual impairment in these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical ND4 G11696A mutation associated with LHON. Indeed, this mutation is present in homoplasmy only in the maternal lineage of those pedigrees but not other members of these families. In fact, the occurrence of the G11696A mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Furthermore, the N405D in the ND5 and G5820A in the tRNA Cys , showing high evolutional conservation, may contribute to the phenotypic expression of G11696A mutation in the WZ10 pedigree. However, there was the absence of functionally significant mtDNA mutations in other four Chinese pedigrees carrying the G11696A mutation. Therefore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic expression of the LHON-associated G11696A mutation in these Chinese pedigrees

  20. Mutations and chromosomal aberrations

    International Nuclear Information System (INIS)

    Kihlman, B.A.

    1977-01-01

    The genetic changes of mutations and chromosomal aberrations are discussed. The consequences of both depend not only on the type of genetic change produced but also on the type of cell that is affected and on the development stage of the organism. (C.F.)

  1. Mutations in GABRB3

    DEFF Research Database (Denmark)

    Møller, Rikke S; Wuttke, Thomas V; Helbig, Ingo

    2017-01-01

    OBJECTIVE: To examine the role of mutations in GABRB3 encoding the β3 subunit of the GABAA receptor in individual patients with epilepsy with regard to causality, the spectrum of genetic variants, their pathophysiology, and associated phenotypes. METHODS: We performed massive parallel sequencing ...

  2. Kin Selection - Mutation Balance

    DEFF Research Database (Denmark)

    Dyken, J. David Van; Linksvayer, Timothy Arnold; Wade, Michael J.

    2011-01-01

    selection-mutation balance, which provides an evolutionary null hypothesis for the statics and dynamics of cheating. When social interactions have linear fitness effects and Hamilton´s rule is satisfied, selection is never strong enough to eliminate recurrent cheater mutants from a population, but cheater...

  3. Audiometric Characteristics of a Dutch DFNA10 Family With Mid-Frequency Hearing Impairment.

    Science.gov (United States)

    van Beelen, Eline; Oonk, Anne M M; Leijendeckers, Joop M; Hoefsloot, Elisabeth H; Pennings, Ronald J E; Feenstra, Ilse; Dieker, Hendrik-Jan; Huygen, Patrick L M; Snik, Ad F M; Kremer, Hannie; Kunst, Henricus P M

    2016-01-01

    Mutations in EYA4 can cause nonsyndromic autosomal dominant sensorineural hearing impairment (DFNA10) or a syndromic variant with hearing impairment and dilated cardiomyopathy. A mutation in EYA4 was found in a Dutch family, causing DFNA10. This study is focused on characterizing the hearing impairment in this family. Whole exome sequencing was performed in the proband. In addition, peripheral blood samples were collected from 23 family members, and segregation analyses were performed. All participants underwent otorhinolaryngological examinations and pure-tone audiometry, and 12 participants underwent speech audiometry. In addition, an extended set of audiometric measurements was performed in five family members to evaluate the functional status of the cochlea. Vestibular testing was performed in three family members. Two individuals underwent echocardiography to evaluate the nonsyndromic phenotype. The authors present a Dutch family with a truncating mutation in EYA4 causing a mid-frequency hearing impairment. This mutation (c.464del) leads to a frameshift and a premature stop codon (p.Pro155fsX). This mutation is the most N-terminal mutation in EYA4 found to date. In addition, a missense mutation, predicted to be deleterious, was found in EYA4 in two family members. Echocardiography in two family members revealed no signs of dilated cardiomyopathy. Results of caloric and velocity step tests in three family members showed no abnormalities. Hearing impairment was found to be symmetric and progressive, beginning as a mid-frequency hearing impairment in childhood and developing into a high-frequency, moderate hearing impairment later in life. Furthermore, an extended set of audiometric measurements was performed in five family members. The results were comparable to those obtained in patients with other sensory types of hearing impairments, such as patients with Usher syndrome type IIA and presbyacusis, and not to those obtained in patients with (cochlear

  4. Structural and functional analysis of APOA5 mutations identified in patients with severe hypertriglyceridemia[S

    Science.gov (United States)

    Mendoza-Barberá, Elena; Julve, Josep; Nilsson, Stefan K.; Lookene, Aivar; Martín-Campos, Jesús M.; Roig, Rosa; Lechuga-Sancho, Alfonso M.; Sloan, John H.; Fuentes-Prior, Pablo; Blanco-Vaca, Francisco

    2013-01-01

    During the diagnosis of three unrelated patients with severe hypertriglyceridemia, three APOA5 mutations [p.(Ser232_Leu235)del, p.Leu253Pro, and p.Asp332ValfsX4] were found without evidence of concomitant LPL, APOC2, or GPIHBP1 mutations. The molecular mechanisms by which APOA5 mutations result in severe hypertriglyceridemia remain poorly understood, and the functional impairment/s induced by these specific mutations was not obvious. Therefore, we performed a thorough structural and functional analysis that included follow-up of patients and their closest relatives, measurement of apoA-V serum concentrations, and sequencing of the APOA5 gene in 200 nonhyperlipidemic controls. Further, we cloned, overexpressed, and purified both wild-type and mutant apoA-V variants and characterized their capacity to activate LPL. The interactions of recombinant wild-type and mutated apoA-V variants with liposomes of different composition, heparin, LRP1, sortilin, and SorLA/LR11 were also analyzed. Finally, to explore the possible structural consequences of these mutations, we developed a three-dimensional model of full-length, lipid-free human apoA-V. A complex, wide array of impairments was found in each of the three mutants, suggesting that the specific residues affected are critical structural determinants for apoA-V function in lipoprotein metabolism and, therefore, that these APOA5 mutations are a direct cause of hypertriglyceridemia. PMID:23307945

  5. Mutations in galactosemia

    Energy Technology Data Exchange (ETDEWEB)

    Reichardt, J.K.V. [Univ. of Southern California School of Medicine, Los Angeles, CA (United States)

    1995-10-01

    This Letter raises four issues concerning two papers on galactosemia published in the March 1995 of the Journal. First, table 2 in the paper by Elsas et al. incorrectly attributes seven galactose-l-phosphate uridyl transferase (GALT) mutations (S135L, L195P, K285N, N314D, R333W, R333G, and K334R). The table also fails to mention that others have reported the same two findings attributed to {open_quotes}Leslie et al.; Elsas et al. and in press{close_quotes} and {open_quotes}Leslie et al.; Elsas et al.{close_quotes} The first finding on the prevalence of the Q188R galactosemia mutation in the G/G Caucasian population has also been described by Ng et al., and the second finding on the correlation of the N314D GALT mutation with the Duarte variant was reported by Lin et al. Second, Elsas et al. suggest that the E203K and N314D mutations may {open_quotes}produce intra-allelic complementation when in cis{close_quotes}. This speculation is supported by the activity data of individual III-2 but is inconsistent with the activities of three other individuals I-1, II-1, and III-1 of the same pedigree. The GALT activity measured in these three individuals suggests a dominant negative effect of E203K in E203K-N314D chromosomes, since they all have less than normal activity. Thus, the preponderance of the data in this paper is at odds with the authors speculation. It is worth recalling that Lin et al. also identified four N314D GALT mutations on 95 galactosemic chromosomes examined. A similar situation also appears to be the case in proband III-1 (with genotype E203K-N314D/IVSC) in the Elsas et al. paper. 9 refs.

  6. Mutation breeding newsletter. No. 45

    International Nuclear Information System (INIS)

    2001-07-01

    This issue of the Mutation Breeding newsletter contains 39 articles dealing with radiation induced mutations and chemical mutagenesis techniques in plant breeding programs with the aims of improving crop productivity and disease resistance as well as exploring genetic variabilities

  7. Mutation breeding newsletter. No. 33

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-01-01

    This issue of the newsletter reports a number of research news and research abstracts on application of radiation induced mutation techniques to increase mutagenesis and mutation frequency in plant breeding projects.

  8. Mutation breeding newsletter. No. 33

    International Nuclear Information System (INIS)

    1989-01-01

    This issue of the newsletter reports a number of research news and research abstracts on application of radiation induced mutation techniques to increase mutagenesis and mutation frequency in plant breeding projects

  9. Congenital hearing impairment

    Energy Technology Data Exchange (ETDEWEB)

    Robson, Caroline D. [Children' s Hospital and Harvard Medical School, Division of Neuroradiology, Department of Radiology, Boston, MA (United States)

    2006-04-15

    Establishing the etiology of congenital hearing impairment can significantly improve treatment for certain causes of hearing loss and facilitates genetic counseling. High-resolution CT and MRI have contributed to the evaluation and management of hearing impairment. In addition, with the identification of innumerable genetic loci and genetic defects involved in hearing loss, genetic testing has emerged as an invaluable tool in the assessment of hearing impairment. Some of the common forms of congenital hearing loss are reviewed and their imaging features illustrated. (orig.)

  10. Congenital hearing impairment

    International Nuclear Information System (INIS)

    Robson, Caroline D.

    2006-01-01

    Establishing the etiology of congenital hearing impairment can significantly improve treatment for certain causes of hearing loss and facilitates genetic counseling. High-resolution CT and MRI have contributed to the evaluation and management of hearing impairment. In addition, with the identification of innumerable genetic loci and genetic defects involved in hearing loss, genetic testing has emerged as an invaluable tool in the assessment of hearing impairment. Some of the common forms of congenital hearing loss are reviewed and their imaging features illustrated. (orig.)

  11. Progranulin mutation causes frontotemporal dementia in the Swedish Karolinska family.

    Science.gov (United States)

    Chiang, Huei-Hsin; Rosvall, Lina; Brohede, Jesper; Axelman, Karin; Björk, Behnosh F; Nennesmo, Inger; Robins, Tiina; Graff, Caroline

    2008-11-01

    Frontotemporal dementia (FTD) is a neurodegenerative disease characterized by cognitive impairment, language dysfunction, and/or changes in personality. Recently it has been shown that progranulin (GRN) mutations can cause FTD as well as other neurodegenerative phenotypes. DNA from 30 family members, of whom seven were diagnosed with FTD, in the Karolinska family was available for GRN sequencing. Fibroblast cell mRNA from one affected family member and six control individuals was available for relative quantitative real-time polymerase chain reaction to investigate the effect of the mutation. Furthermore, the cDNA of an affected individual was sequenced. Clinical and neuropathologic findings of a previously undescribed family branch are presented. A frameshift mutation in GRN (g.102delC) was detected in all affected family members and absent in four unaffected family members older than 70 years. Real-time polymerase chain reaction data showed an approximately 50% reduction of GRN fibroblast mRNA in an affected individual. The mutated mRNA transcripts were undetectable by cDNA sequencing. Segregation and RNA analyses showed that the g.102delC mutation, previously reported, causes FTD in the Karolinska family. Our findings add further support to the significance of GRN in FTD etiology and the presence of modifying genes, which emphasize the need for further studies into the mechanisms of clinical heterogeneity. However, the results already call for attention to the complexity of predictive genetic testing of GRN mutations.

  12. A comprehensive characterization of mitochondrial DNA mutations in glioblastoma multiforme.

    Science.gov (United States)

    Vidone, Michele; Clima, Rosanna; Santorsola, Mariangela; Calabrese, Claudia; Girolimetti, Giulia; Kurelac, Ivana; Amato, Laura Benedetta; Iommarini, Luisa; Trevisan, Elisa; Leone, Marco; Soffietti, Riccardo; Morra, Isabella; Faccani, Giuliano; Attimonelli, Marcella; Porcelli, Anna Maria; Gasparre, Giuseppe

    2015-06-01

    Glioblastoma multiforme (GBM) is the most malignant brain cancer in adults, with a poor prognosis, whose molecular stratification still represents a challenge in pathology and clinics. On the other hand, mitochondrial DNA (mtDNA) mutations have been found in most tumors as modifiers of the bioenergetics state, albeit in GBM a characterization of the mtDNA status is lacking to date. Here, a characterization of the burden of mtDNA mutations in GBM samples was performed. First, investigation of tumor-specific vs. non tumor-specific mutations was carried out with the MToolBox bioinformatics pipeline by analyzing 45 matched tumor/blood samples, from whole genome or whole exome sequencing datasets obtained from The Cancer Genome Atlas (TCGA) consortium. Additionally, the entire mtDNA sequence was obtained in a dataset of 104 fresh-frozen GBM samples. Mitochondrial mutations with potential pathogenic interest were prioritized based on heteroplasmic fraction, nucleotide variability, and in silico prediction of pathogenicity. A preliminary biochemical analysis of the activity of mitochondrial respiratory complexes was also performed on fresh-frozen GBM samples. Although a high number of mutations was detected, we report that the large majority of them does not pass the prioritization filters. Therefore, a relatively limited burden of pathogenic mutations is indeed carried by GBM, which did not appear to determine a general impairment of the respiratory chain. This article is part of a Directed Issue entitled: Energy Metabolism Disorders and Therapies. Copyright © 2015 Elsevier Ltd. All rights reserved.

  13. Impairment of ceramide synthesis causes a novel progressive myoclonus epilepsy.

    Science.gov (United States)

    Vanni, Nicola; Fruscione, Floriana; Ferlazzo, Edoardo; Striano, Pasquale; Robbiano, Angela; Traverso, Monica; Sander, Thomas; Falace, Antonio; Gazzerro, Elisabetta; Bramanti, Placido; Bielawski, Jacek; Fassio, Anna; Minetti, Carlo; Genton, Pierre; Zara, Federico

    2014-08-01

    Alterations of sphingolipid metabolism are implicated in the pathogenesis of many neurodegenerative disorders. We identified a homozygous nonsynonymous mutation in CERS1, the gene encoding ceramide synthase 1, in 4 siblings affected by a progressive disorder with myoclonic epilepsy and dementia. CerS1, a transmembrane protein of the endoplasmic reticulum (ER), catalyzes the biosynthesis of C18-ceramides. We demonstrated that the mutation decreases C18-ceramide levels. In addition, we showed that downregulation of CerS1 in a neuroblastoma cell line triggers ER stress response and induces proapoptotic pathways. This study demonstrates that impairment of ceramide biosynthesis underlies neurodegeneration in humans. © 2014 American Neurological Association.

  14. Mutation analysis in the long isoform of USH2A in American patients with Usher Syndrome type II.

    Science.gov (United States)

    Yan, Denise; Ouyang, Xiaomei; Patterson, D Michael; Du, Li Lin; Jacobson, Samuel G; Liu, Xue-Zhong

    2009-12-01

    Usher syndrome type II (USH2) is an autosomal recessive disorder characterized by moderate to severe hearing impairment and progressive visual loss due to retinitis pigmentosa (RP). To identify novel mutations and determine the frequency of USH2A mutations as a cause of USH2, we have carried out mutation screening of all 72 coding exons and exon-intron splice sites of the USH2A gene. A total of 20 USH2 American probands of European descent were analyzed using single strand conformational polymorphism (SSCP) and direct sequencing methods. Ten different USH2A mutations were identified in 55% of the probands, five of which were novel mutations. The detected mutations include three missense, three frameshifts and four nonsense mutations, with c.2299delG/p.E767fs mutation, accounting for 38.9% of the pathological alleles. Two cases were homozygotes, two cases were compound heterozygotes and one case had complex allele with three variants. In seven probands, only one USH2A mutation was detected and no pathological mutation was found in the remaining eight individuals. Altogether, our data support the fact that c.2299delG/p.E767fs is indeed the most common USH2A mutation found in USH2 patients of European Caucasian background. Thus, if screening for mutations in USH2A is considered, it is reasonable to screen for the c.2299delG mutation first.

  15. Impairments to Vision

    Science.gov (United States)

    ... an external Non-Government web site. Impairments to Vision Normal Vision Diabetic Retinopathy Age-related Macular Degeneration In this ... pictures, fixate on the nose to simulate the vision loss. In diabetic retinopathy, the blood vessels in ...

  16. Stormwater Impaired Watersheds

    Data.gov (United States)

    Vermont Center for Geographic Information — Stormwater impaired watersheds occuring on both the Priority Waters (Part D - Completed TMDL) and 303(d) list of waters (Part A - need TMDL) The Vermont State...

  17. Mutational screening of the USH2A gene in Spanish USH patients reveals 23 novel pathogenic mutations

    Directory of Open Access Journals (Sweden)

    Diaz-Llopis Manuel

    2011-10-01

    Full Text Available Abstract Background Usher Syndrome type II (USH2 is an autosomal recessive disorder, characterized by moderate to severe hearing impairment and retinitis pigmentosa (RP. Among the three genes implicated, mutations in the USH2A gene account for 74-90% of the USH2 cases. Methods To identify the genetic cause of the disease and determine the frequency of USH2A mutations in a cohort of 88 unrelated USH Spanish patients, we carried out a mutation screening of the 72 coding exons of this gene by direct sequencing. Moreover, we performed functional minigene studies for those changes that were predicted to affect splicing. Results As a result, a total of 144 DNA sequence variants were identified. Based upon previous studies, allele frequencies, segregation analysis, bioinformatics' predictions and in vitro experiments, 37 variants (23 of them novel were classified as pathogenic mutations. Conclusions This report provide a wide spectrum of USH2A mutations and clinical features, including atypical Usher syndrome phenotypes resembling Usher syndrome type I. Considering only the patients clearly diagnosed with Usher syndrome type II, and results obtained in this and previous studies, we can state that mutations in USH2A are responsible for 76.1% of USH2 disease in patients of Spanish origin.

  18. A novel TECTA mutation in a Dutch DFNA8/12 family confirms genotype-phenotype correlation.

    NARCIS (Netherlands)

    Plantinga, R.F.; Brouwer, A.P.M. de; Huygen, P.L.M.; Kunst, H.P.M.; Kremer, H.; Cremers, C.W.R.J.

    2006-01-01

    A novel TECTA mutation, p.R1890C, was found in a Dutch family with nonsyndromic autosomal dominant sensorineural hearing impairment. In early life, presumably congenital, hearing impairment occurred in the midfrequency range, amounting to about 40 dB at 1 kHz. Speech recognition was good with all

  19. Mutation breeding in pepper

    Energy Technology Data Exchange (ETDEWEB)

    Daskalov, S [Plant Breeding Unit, Joint FAO/IAEA Division of Isotope and Radiation Applications of Atomic Energy for Food and Agricultural Development, Seibersdorf Laboratory, International Atomic Energy Agency, Vienna (Austria)

    1986-03-01

    Pepper (Capsicum sp.) is an important vegetable and spice crop widely grown in tropical as well as in temperate regions. Until recently the improvement programmes were based mainly on using natural sources of germ plasma, crossbreeding and exploiting the heterosis of F{sub 1} hybrids. However, interest in using induced mutations is growing. A great number of agronomically useful mutants as well as mutants valuable for genetic, cytological and physiological studies have been induced and described. In this review information is presented about suitable mutagen treatment procedures with radiation as well as chemicals, M{sub 1} effects, handling the treated material in M{sub 1}, M{sub 2} and subsequent generations, and mutant screening procedures. This is supplemented by a description of reported useful mutants and released cultivars. Finally, general advice is given on when and how to incorporate mutation induction in Capsicum improvement programmes. (author)

  20. Mutation breeding in pepper

    International Nuclear Information System (INIS)

    Daskalov, S.

    1986-01-01

    Pepper (Capsicum sp.) is an important vegetable and spice crop widely grown in tropical as well as in temperate regions. Until recently the improvement programmes were based mainly on using natural sources of germ plasma, crossbreeding and exploiting the heterosis of F 1 hybrids. However, interest in using induced mutations is growing. A great number of agronomically useful mutants as well as mutants valuable for genetic, cytological and physiological studies have been induced and described. In this review information is presented about suitable mutagen treatment procedures with radiation as well as chemicals, M 1 effects, handling the treated material in M 1 , M 2 and subsequent generations, and mutant screening procedures. This is supplemented by a description of reported useful mutants and released cultivars. Finally, general advice is given on when and how to incorporate mutation induction in Capsicum improvement programmes. (author)

  1. Neutral lipid-storage disease with myopathy and extended phenotype with novel PNPLA2 mutation.

    Science.gov (United States)

    Massa, Roberto; Pozzessere, Simone; Rastelli, Emanuele; Serra, Laura; Terracciano, Chiara; Gibellini, Manuela; Bozzali, Marco; Arca, Marcello

    2016-04-01

    Neutral lipid-storage disease with myopathy is caused by mutations in PNPLA2, which produce skeletal and cardiac myopathy. We report a man with multiorgan neutral lipid storage and unusual multisystem clinical involvement, including cognitive impairment. Quantitative brain MRI with voxel-based morphometry and extended neuropsychological assessment were performed. In parallel, the coding sequences and intron/exon boundaries of the PNPLA2 gene were screened by direct sequencing. Neuropsychological assessment revealed global cognitive impairment, and brain MRI showed reduced gray matter volume in the temporal lobes. Molecular characterization revealed a novel homozygous mutation in exon 5 of PNPLA2 (c.714C>A), resulting in a premature stop codon (p.Cys238*). Some PNPLA2 mutations, such as the one described here, may present with an extended phenotype, including brain involvement. In these cases, complete neuropsychological testing, combined with quantitative brain MRI, may help to characterize and quantify cognitive impairment. © 2016 Wiley Periodicals, Inc.

  2. A novel MKRN3 missense mutation causing familial precocious puberty.

    Science.gov (United States)

    de Vries, L; Gat-Yablonski, G; Dror, N; Singer, A; Phillip, M

    2014-12-01

    Central precocious puberty may be familial in about a quarter of the idiopathic cases. However, little is known about the genetic causes responsible for the disorder. In this report we describe a family with central precocious puberty associated with a mutation in the makorin RING-finger protein 3 (MKRN3) gene. A novel missense mutation (p.H420Q) in the imprinted MKRN3 gene was identified in the four affected siblings, in their unaffected father and in his affected mother. An in silico mutant MKRN3 model predicts that the mutation p.H420Q leads to reduced zinc binding and, subsequently, impaired RNA binding. These findings support the fundamental role of the MKRN3 protein in determining pubertal timing. © The Author 2014. Published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  3. Filaggrin loss-of-function mutations and incident cancer

    DEFF Research Database (Denmark)

    Skaaby, T; Husemoen, L L N; Thyssen, J P

    2014-01-01

    BACKGROUND: Loss-of-function mutations in the filaggrin gene (FLG) could have opposing effects on cancer risk, as mutations are associated with both 10% higher serum vitamin D levels, which may protect against cancer, and with impaired skin barrier function, which may lead to higher cancer...... (HR 1·09, 95% CI 0·61-1·94), urinary cancer (HR 1·30, 95% CI 0·51-3·29), malignant melanoma (HR 1·03, 95% CI 0·41-2·58) and NMSC (HR 0·70, 95% CI 0·47-1·05). Among participants aged over 60 years at baseline, we found statistically significant lower risks of all cancers and NMSC among FLG mutation...

  4. A nonsense mutation in FMR1 causing fragile X syndrome

    DEFF Research Database (Denmark)

    Grønskov, Karen; Brøndum-Nielsen, Karen; Dedic, Alma

    2011-01-01

    Fragile X syndrome is a common cause of inherited intellectual disability. It is caused by lack of the FMR1 gene product FMRP. The most frequent cause is the expansion of a CGG repeat located in the 5'UTR of FMR1. Alleles with 200 or more repeats become hypermethylated and transcriptionally silent....... Only few patients with intragenic point mutations in FMR1 have been reported and, currently, routine analysis of patients referred for fragile X syndrome includes solely analysis for repeat expansion and methylation status. We identified a substitution in exon 2 of FMR1, c.80C>A, causing a nonsense...... mutation p.Ser27X, in a patient with classical clinical symptoms of fragile X syndrome. The mother who carried the mutation in heterozygous form presented with mild intellectual impairment. We conclude that further studies including western blot and DNA sequence analysis of the FMR1 gene should...

  5. Mutated hilltop inflation revisited

    Science.gov (United States)

    Pal, Barun Kumar

    2018-05-01

    In this work we re-investigate pros and cons of mutated hilltop inflation. Applying Hamilton-Jacobi formalism we solve inflationary dynamics and find that inflation goes on along the {W}_{-1} branch of the Lambert function. Depending on the model parameter mutated hilltop model renders two types of inflationary solutions: one corresponds to small inflaton excursion during observable inflation and the other describes large field inflation. The inflationary observables from curvature perturbation are in tune with the current data for a wide range of the model parameter. The small field branch predicts negligible amount of tensor to scalar ratio r˜ O(10^{-4}), while the large field sector is capable of generating high amplitude for tensor perturbations, r˜ O(10^{-1}). Also, the spectral index is almost independent of the model parameter along with a very small negative amount of scalar running. Finally we find that the mutated hilltop inflation closely resembles the α -attractor class of inflationary models in the limit of α φ ≫ 1.

  6. Mutation breeding in jute

    International Nuclear Information System (INIS)

    Joshua, D.C.

    1980-01-01

    Mutagenic studies in jute in general dealt with the morphological abnormalities of the M 1 generation in great detail. Of late, induction of a wide spectrum of viable mutations have been reported in different varieties of both the species. Mutations affecting several traits of agronomic importance such as, plant height, time of flowering, fibre yield and quality, resistance to pests and diseases are also available. Cytological analysis of a large collection of induced mutants resulted in the isolation of seven trisomics in an olitorius variety. Several anatomical parameters which are the components of fibre yield, have also received attention. Some mutants with completely altered morphology were used for interpreting the evolution of leaf shape in Tiliaceas and related families. A capsularis variety developed using mutation breeding technique has been released for cultivation. Several others, including derivatives of inter-mutant hybridization have been found to perform well at different locations in the All India Coordinated Trials. Presently, chemical mutagenesis and induction of mutants of physiological significance are receiving considerable attention. The induced variability is being used in genetic and linkage studies. (author)

  7. Calreticulin Mutations in Myeloproliferative Neoplasms

    Directory of Open Access Journals (Sweden)

    Noa Lavi

    2014-10-01

    Full Text Available With the discovery of the JAK2V617F mutation in patients with Philadelphia chromosome-negative (Ph− myeloproliferative neoplasms (MPNs in 2005, major advances have been made in the diagnosis of MPNs, in understanding of their pathogenesis involving the JAK/STAT pathway, and finally in the development of novel therapies targeting this pathway. Nevertheless, it remains unknown which mutations exist in approximately one-third of patients with non-mutated JAK2 or MPL essential thrombocythemia (ET and primary myelofibrosis (PMF. At the end of 2013, two studies identified recurrent mutations in the gene encoding calreticulin (CALR using whole-exome sequencing. These mutations were revealed in the majority of ET and PMF patients with non-mutated JAK2 or MPL but not in polycythemia vera patients. Somatic 52-bp deletions (type 1 mutations and recurrent 5-bp insertions (type 2 mutations in exon 9 of the CALR gene (the last exon encoding the C-terminal amino acids of the protein calreticulin were detected and found always to generate frameshift mutations. All detected mutant calreticulin proteins shared a novel amino acid sequence at the C-terminal. Mutations in CALR are acquired early in the clonal history of the disease, and they cause activation of JAK/STAT signaling. The CALR mutations are the second most frequent mutations in Ph− MPN patients after the JAK2V617F mutation, and their detection has significantly improved the diagnostic approach for ET and PMF. The characteristics of the CALR mutations as well as their diagnostic, clinical, and pathogenesis implications are discussed in this review.

  8. Mitochondrial leukoencephalopathy and complex II deficiency associated with a recessive SDHB mutation with reduced penetrance

    Directory of Open Access Journals (Sweden)

    Anna Ardissone

    2015-12-01

    Full Text Available Mitochondrial disease involving complex II is rare among respiratory chain deficiencies and its genetic cause remains often unknown. Two main clinical presentations are associated with this biochemical defect: mitochondrial encephalomyopathy and susceptibility to tumors. Only one homozygous SDHB mutation has been described in a patient with mitochondrial disorder. We report here two sisters, who presented highly different phenotypes (neurological impairment with leukoencephalopathy vs. asymptomatic status and harbored the same homozygous SDHB mutation, suggesting reduced penetrance.

  9. Damaging de novo mutations diminish motor skills in children on the autism spectrum.

    Science.gov (United States)

    Buja, Andreas; Volfovsky, Natalia; Krieger, Abba M; Lord, Catherine; Lash, Alex E; Wigler, Michael; Iossifov, Ivan

    2018-02-20

    In individuals with autism spectrum disorder (ASD), de novo mutations have previously been shown to be significantly correlated with lower IQ but not with the core characteristics of ASD: deficits in social communication and interaction and restricted interests and repetitive patterns of behavior. We extend these findings by demonstrating in the Simons Simplex Collection that damaging de novo mutations in ASD individuals are also significantly and convincingly correlated with measures of impaired motor skills. This correlation is not explained by a correlation between IQ and motor skills. We find that IQ and motor skills are distinctly associated with damaging mutations and, in particular, that motor skills are a more sensitive indicator of mutational severity than is IQ, as judged by mutational type and target gene. We use this finding to propose a combined classification of phenotypic severity: mild (little impairment of either), moderate (impairment mainly to motor skills), and severe (impairment of both IQ and motor skills). Copyright © 2018 the Author(s). Published by PNAS.

  10. Mutation breeding in chickpea

    International Nuclear Information System (INIS)

    2009-01-01

    Chickpea is an important food legume in Turkey. Turkey is one of the most important gene centers in the world for legumes. The most widely known characteristic of chickpea is that it is an important vegetable protein source used in human and animal nutrition. However, the dry grains of chickpea, has 2-3 times more protein than our traditional food of wheat. In addition, cheakpea is also energy source because of its high carbohydrate content. It is very rich in some vitamin and mineral basis. In the plant breeding, mutation induction has become an effective way of supplementing existing germplasm and improving cultivars. Many successful examples of mutation induction have proved that mutation breeding is an effective and important approach to food legume improvement. The induced mutation technique in chickpea has proved successful and good results have been attained. Realizing the potential of induced mutations, a mutation breeding programme was initiated at the Nuclear Agriculture Section of the Saraykoey Nuclear Research and Training Center in 1994. The purpose of the study was to obtain high yielding chickpea mutants with large seeds, good cooking quality and high protein content. Beside this some characters such as higher adaptation ability, tolerant to cold and drought, increased machinery harvest type, higher yield, resistant to diseases especially to antracnose and pest were investigated too. Parents varieties were ILC-482, AK-7114 and AKCIN-91 (9 % seed moisture content and germination percentage 98 %) in these experiments. The irradiation doses were 0 (control), 50, 100, 150, 200, 250, 300, 350, 400, 500 ve 600 Gy for greenhouse experiments and 0 (control), 50, 100, 150, 200, 250, 300, 350 ve 400 Gy for field experiments, respectively. One thousand seeds for per treatment were sown in the field for the M 1 . At maturity, 3500 single plants were harvested and 20 seeds were taken from each M 1 plant and planted in the following season. During plant growth

  11. Vascular cognitive impairment

    Directory of Open Access Journals (Sweden)

    N.V. Vakhnina

    2014-01-01

    Full Text Available Vascular pathology of the brain is the second most common cause of cognitive impairment after Alzheimer's disease. The article describes the modern concepts of etiology, pathogenetic mechanisms, clinical features and approaches to diagnosis and therapy of vascular cognitive impairment (VCI. Cerebrovascular accident, chronic cerebral circulatory insufficiency and their combination, sometimes in combination with a concomitant neurodegenerative process, are shown to be the major types of brain lesions leading to VCI. The clinical presentation of VCI is characterized by the neuropsychological status dominated by impairment of the executive frontal functions (planning, control, attention in combination with focal neurological symptoms. The diagnosis is based on comparing of the revealed neuropsychological and neurological features with neuroimaging data. Neurometabolic, acetylcholinergic, glutamatergic, and other vasoactive drugs and non-pharmacological methods are widely used to treat VCI. 

  12. Lithium and Renal Impairment

    DEFF Research Database (Denmark)

    Nielsen, René Ernst; Kessing, Lars Vedel; Nolen, Willem A

    2018-01-01

    INTRODUCTION: Lithium is established as an effective treatment of mania, of depression in bipolar and unipolar disorder, and in maintenance treatment of these disorders. However, due to the necessity of monitoring and concerns about irreversible adverse effects, in particular renal impairment......, after long-term use, lithium might be underutilized. METHODS: This study reviewed 6 large observational studies addressing the risk of impaired renal function associated with lithium treatment and methodological issues impacting interpretation of results. RESULTS: An increased risk of renal impairment...... associated with lithium treatment is suggested. This increased risk may, at least partly, be a result of surveillance bias. Additionally, the earliest studies pointed toward an increased risk of end-stage renal disease associated with lithium treatment, whereas the later and methodologically most sound...

  13. Induced mutations in citrus

    International Nuclear Information System (INIS)

    Spiegel-Roy, P.; Vardi, Aliza

    1990-01-01

    Full text: Parthenocarpic tendency is an important prerequisite for successful induction of seedlessness in breeding and especially in mutation breeding. A gene for asynapsis and accompanying seedless fruit has been found by us in inbred progeny of cv. 'Wilking'. Using budwood irradiation by gamma rays, seedless mutants of 'Eureka' and 'Villafranca' lemon (original clone of the latter has 25 seeds) and 'Minneola' tangelo have been obtained. Ovule sterility of the three mutants is nearly complete, with some pollen fertility still remaining. A semi-compact mutant of Shamouti orange has been obtained by irradiation. A programme for inducing seedlessness in easy peeling citrus varieties and selections has been initiated. (author)

  14. Induced skeletal mutations

    International Nuclear Information System (INIS)

    Selby, P.B.

    1979-01-01

    This paper describes a large-scale experiment that, by means of breeding tests, confirmed that many dominant skeletal mutations are induced by large-dose radiation exposure. The author also discusses: (1) the major advantages and disadvantages of the skeletal method in improving estimates of genetic hazard to man; (2) future uses of the skeletal method; (3) direct estimation of risk beyond the first generation using the skeletal method; and (4) the possibility of using the skeletal method as a quick and easy screen for chemical mutagens

  15. Novel USH2A compound heterozygous mutations cause RP/USH2 in a Chinese family.

    Science.gov (United States)

    Liu, Xiaowen; Tang, Zhaohui; Li, Chang; Yang, Kangjuan; Gan, Guanqi; Zhang, Zibo; Liu, Jingyu; Jiang, Fagang; Wang, Qing; Liu, Mugen

    2010-03-17

    To identify the disease-causing gene in a four-generation Chinese family affected with retinitis pigmentosa (RP). Linkage analysis was performed with a panel of microsatellite markers flanking the candidate genetic loci of RP. These loci included 38 known RP genes. The complete coding region and exon-intron boundaries of Usher syndrome 2A (USH2A) were sequenced with the proband DNA to screen the disease-causing gene mutation. Restriction fragment length polymorphism (RFLP) analysis and direct DNA sequence analysis were done to demonstrate co-segregation of the USH2A mutations with the family disease. One hundred normal controls were used without the mutations. The disease-causing gene in this Chinese family was linked to the USH2A locus on chromosome 1q41. Direct DNA sequence analysis of USH2A identified two novel mutations in the patients: one missense mutation p.G1734R in exon 26 and a splice site mutation, IVS32+1G>A, which was found in the donor site of intron 32 of USH2A. Neither the p.G1734R nor the IVS32+1G>A mutation was found in the unaffected family members or the 100 normal controls. One patient with a homozygous mutation displayed only RP symptoms until now, while three patients with compound heterozygous mutations in the family of study showed both RP and hearing impairment. This study identified two novel mutations: p.G1734R and IVS32+1G>A of USH2A in a four-generation Chinese RP family. In this study, the heterozygous mutation and the homozygous mutation in USH2A may cause Usher syndrome Type II or RP, respectively. These two mutations expand the mutant spectrum of USH2A.

  16. Social communication impairments: pragmatics.

    Science.gov (United States)

    Russell, Robert L

    2007-06-01

    Social communication or pragmatic impairments are characterized and illustrated as involving inappropriate or ineffective use of language and gesture in social contexts. Three clinical vignettes illustrate different pragmatic impairments and the wealth of diagnostic information that can be garnered from observation of a child's social communication behavior. Definitions of, and developmental milestones in, domains of pragmatic competence are provided. Several screening instruments are suggested for use in assessing pragmatic competence within the time-frame of a pediatric examination. Frequent comorbid psychiatric conditions are described and a sample of current neurobiologic research is briefly summarized.

  17. Crystal structures of wild-type and mutated cyclophilin B that causes hyperelastosis cutis in the American quarter horse

    Directory of Open Access Journals (Sweden)

    Boudko Sergei P

    2012-11-01

    Full Text Available Abstract Background Hyperelastosis cutis is an inherited autosomal recessive connective tissue disorder. Affected horses are characterized by hyperextensible skin, scarring, and severe lesions along the back. The disorder is caused by a mutation in cyclophilin B. Results The crystal structures of both wild-type and mutated (Gly6->Arg horse cyclophilin B are presented. The mutation neither affects the overall fold of the enzyme nor impairs the catalytic site structure. Instead, it locally rearranges the flexible N-terminal end of the polypeptide chain and also makes it more rigid. Conclusions Interactions of the mutated cyclophilin B with a set of endoplasmic reticulum-resident proteins must be affected.

  18. Mutation Breeding Newsletter. No. 39

    International Nuclear Information System (INIS)

    1992-01-01

    This newsletter contains brief articles on the use of radiation to induce mutations in plants; radiation-induced mutants in Chrysanthemum; disrupting the association between oil and protein content in soybean seeds; mutation studies on bougainvillea; a new pepper cultivar; and the use of mutation induction to improve the quality of yam beans. A short review of the seminar on the use of mutation and related biotechnology for crop improvement in the Middle East and Mediterranean regions, and a description of a Co-ordinated Research Programme on the application of DNA-based marker mutations for the improvement of cereals and other sexually reproduced crop species are also included. Two tables are given: these are based on the ''FAO/IAEA Mutant Varieties Database'' and show the number of mutated varieties and the number of officially released mutant varieties in particular crops/species. Refs and tabs

  19. Xeroderma Pigmentosum-Trichothiodystrophy overlap patient with novel XPD/ERCC2 mutation

    DEFF Research Database (Denmark)

    Kralund, Henrik H; Ousager, Lilian; Jaspers, Nicolaas G

    2013-01-01

    outcome from many of these mutations. We demonstrate a patient, believed to represent an overlap between XP and TTD/CS. In addition to other organ dysfunctions, the young man presented with Photosensitivity, Ichthyosis, Brittle hair, Impaired physical and mental development, Decreased fertility and Short...... appearance also suggested XP, but fibroblast cultures only demonstrated x2 UV-sensitivity with expected NER and TFIIH-activity decrease. Genetic sequencing of the XPD/ERCC2 gene established the patient as heterozygote compound with a novel, N-terminal Y18H mutation and a known C-terminal (TTD) mutation, A725...

  20. NDST1 missense mutations in autosomal recessive intellectual disability.

    Science.gov (United States)

    Reuter, Miriam S; Musante, Luciana; Hu, Hao; Diederich, Stefan; Sticht, Heinrich; Ekici, Arif B; Uebe, Steffen; Wienker, Thomas F; Bartsch, Oliver; Zechner, Ulrich; Oppitz, Cornelia; Keleman, Krystyna; Jamra, Rami Abou; Najmabadi, Hossein; Schweiger, Susann; Reis, André; Kahrizi, Kimia

    2014-11-01

    NDST1 was recently proposed as a candidate gene for autosomal recessive intellectual disability in two families. It encodes a bifunctional GlcNAc N-deacetylase/N-sulfotransferase with important functions in heparan sulfate biosynthesis. In mice, Ndst1 is crucial for embryonic development and homozygous null mutations are perinatally lethal. We now report on two additional unrelated families with homozygous missense NDST1 mutations. All mutations described to date predict the substitution of conserved amino acids in the sulfotransferase domain, and mutation modeling predicts drastic alterations in the local protein conformation. Comparing the four families, we noticed significant overlap in the clinical features, including both demonstrated and apparent intellectual disability, muscular hypotonia, epilepsy, and postnatal growth deficiency. Furthermore, in Drosophila, knockdown of sulfateless, the NDST ortholog, impairs long-term memory, highlighting its function in cognition. Our data confirm NDST1 mutations as a cause of autosomal recessive intellectual disability with a distinctive phenotype, and support an important function of NDST1 in human development. © 2014 Wiley Periodicals, Inc.

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

    Directory of Open Access Journals (Sweden)

    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.

  2. Mutations induced in plant breeding

    International Nuclear Information System (INIS)

    Barriga B, P.

    1984-01-01

    The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented. (Author)

  3. Mutations induced in plant breeding

    Energy Technology Data Exchange (ETDEWEB)

    Barriga B, P. (Universidad Austral de Chile, Valdivia. Inst. de Produccion y Sanidad Vegetal)

    1984-10-01

    The most significant aspects of the use of ionizing radiations in plant breeding are reviewed. Aspects such as basic principles of mutation, expression and selection in obtention of mutants, methods for using induced mutations and sucess achieved with this methodology in plant breeding are reviewed. Results obtained in a program of induced mutation on wheat for high content of protein and lysine at the Universidad Austral de Chile are presented.

  4. Xeroderma Pigmentosum: Low Prevalence of Germline XPA Mutations in a Brazilian XP Population

    Directory of Open Access Journals (Sweden)

    Karina Miranda Santiago

    2015-04-01

    Full Text Available Xeroderma pigmentosum (XP is a rare autosomal recessive disorder characterized by DNA repair defects that cause photophobia, sunlight-induced cancers, and neurodegeneration. Prevalence of germline mutations in the nucleotide excision repair gene XPA vary significantly in different populations. No Brazilian patients have been reported to carry a germline mutation in this gene. In this study, the germline mutational status of XPA was determined in Brazilian patients exhibiting major clinical features of XP syndrome. The study was conducted on 27 unrelated patients from select Brazilian families. A biallelic inactivating transition mutation c.619C>T (p.Arg207Ter was identified in only one patient with a history of neurological impairment and mild skin abnormalities. These findings suggest that XP syndrome is rarely associated with inherited disease-causing XPA mutations in the Brazilian population. Additionally, this report demonstrates the effectiveness of genotype-phenotype correlation as a valuable tool to guide direct genetic screening.

  5. Xeroderma pigmentosum: low prevalence of germline XPA mutations in a Brazilian XP population.

    Science.gov (United States)

    Santiago, Karina Miranda; França de Nóbrega, Amanda; Rocha, Rafael Malagoli; Rogatto, Silvia Regina; Achatz, Maria Isabel

    2015-04-22

    Xeroderma pigmentosum (XP) is a rare autosomal recessive disorder characterized by DNA repair defects that cause photophobia, sunlight-induced cancers, and neurodegeneration. Prevalence of germline mutations in the nucleotide excision repair gene XPA vary significantly in different populations. No Brazilian patients have been reported to carry a germline mutation in this gene. In this study, the germline mutational status of XPA was determined in Brazilian patients exhibiting major clinical features of XP syndrome. The study was conducted on 27 unrelated patients from select Brazilian families. A biallelic inactivating transition mutation c.619C>T (p.Arg207Ter) was identified in only one patient with a history of neurological impairment and mild skin abnormalities. These findings suggest that XP syndrome is rarely associated with inherited disease-causing XPA mutations in the Brazilian population. Additionally, this report demonstrates the effectiveness of genotype-phenotype correlation as a valuable tool to guide direct genetic screening.

  6. PYCR2 Mutations cause a lethal syndrome of microcephaly and failure to thrive.

    Science.gov (United States)

    Zaki, Maha S; Bhat, Gifty; Sultan, Tipu; Issa, Mahmoud; Jung, Hea-Jin; Dikoglu, Esra; Selim, Laila; G Mahmoud, Imam; Abdel-Hamid, Mohamed S; Abdel-Salam, Ghada; Marin-Valencia, Isaac; Gleeson, Joseph G

    2016-07-01

    A study was undertaken to characterize the clinical features of the newly described hypomyelinating leukodystrophy type 10 with microcephaly. This is an autosomal recessive disorder mapped to chromosome 1q42.12 due to mutations in the PYCR2 gene, encoding an enzyme involved in proline synthesis in mitochondria. From several international clinics, 11 consanguineous families were identified with PYCR2 mutations by whole exome or targeted sequencing, with detailed clinical and radiological phenotyping. Selective mutations from patients were tested for effect on protein function. The characteristic clinical presentation of patients with PYCR2 mutations included failure to thrive, microcephaly, craniofacial dysmorphism, progressive psychomotor disability, hyperkinetic movements, and axial hypotonia with variable appendicular spasticity. Patients did not survive beyond the first decade of life. Brain magnetic resonance imaging showed global brain atrophy and white matter T2 hyperintensities. Routine serum metabolic profiles were unremarkable. Both nonsense and missense mutations were identified, which impaired protein multimerization. PYCR2-related syndrome represents a clinically recognizable condition in which PYCR2 mutations lead to protein dysfunction, not detectable on routine biochemical assessments. Mutations predict a poor outcome, probably as a result of impaired mitochondrial function. Ann Neurol 2016;80:59-70. © 2016 American Neurological Association.

  7. Mutation breeding newsletter. No. 43

    International Nuclear Information System (INIS)

    1997-10-01

    This issue of the Newsletter includes articles dealing with radiation induced mutation based plant breeding research findings aimed at improving productivity, disease resistance and tolerance of stress conditions

  8. Mutation breeding in mangosteen

    International Nuclear Information System (INIS)

    Mohd Khalid Mohd Zain

    2002-01-01

    Mangosteen the queen of the tropical fruits is apomitic and only a cultivar is reported and it reproduces asexually. Conventional breeding is not possible and the other methods to create variabilities are through genetic engineering and mutation breeding. The former technique is still in the infantry stage in mangosteen research while the latter has been an established tool in breeding to improve cultivars. In this mutation breeding seeds of mangosteen were irradiated using gamma rays and the LD 50 for mangosteen was determined and noted to be very low at 10 Gy. After sowing in the seedbed, the seedlings were transplanted in polybags and observed in the nursery bed for about one year before planted in the field under old oil palm trees in Station MARDI, Kluang. After evaluation and screening, about 120 mutant mangosteen plants were selected and planted in Kluang. The plants were observed and some growth data taken. There were some mutant plants that have good growth vigour and more vigorous that the control plants. The trial are now in the fourth year and the plants are still in the juvenile stage. (Author)

  9. Mutation breeding in chickpea

    International Nuclear Information System (INIS)

    Sagel, Z.; Tutluer, M. I.; Peskircioglu, H.; Kantoglu, Y.; Kunter, B.

    2009-01-01

    Chickpea is an important food legume in Turkey. Turkey is one of the most important gene centers in the world for legumes. Realizing the potential of induced mutations, a mutation breeding programme was initiated at the Nuclear Agriculture Section of the Saraykoy Nuclear Research and Training Center in 1994. The purpose of the study was to obtain high yielding chickpea mutants with large seeds, good cooking quality and high protein content. Beside this some characters such as higher adaptation ability, tolerant to cold and drought, increased machinery harvest type, higher yield, resistant to diseases especially to antracnose and pest were investigated too. Parent varieties were ILC-482, AK-7114 and AKCIN-91 had been used in these experiments. The irradiation doses were 0 (control), 50, 100, 150, 200, 250, 300, 350 and 400 Gy for field experiments, respectively. As a result of these experiments, two promising mutant lines were chosen and given to the Seed Registration and Certification Center for official registration These two promising mutants were tested at five different locations of Turkey, in 2004 and 2005 years. After 2 years of registration experiments one of outstanding mutants was officially released as mutant chickpea variety under the name TAEK-SAGEL, in 2006. Some basic characteristics of this mutant are; earliness (95-100 day), high yield capacity (180-220 kg/da), high seed protein (22-25 %), first pot height (20-25 cm), 100 seeds weight (42-48 g), cooking time (35-40 min) and resistance to Ascochyta blight.

  10. Diseases associated with growth hormone-releasing hormone receptor (GHRHR) mutations.

    Science.gov (United States)

    Martari, Marco; Salvatori, Roberto

    2009-01-01

    The growth hormone (GH)-releasing hormone (GHRH) receptor (GHRHR) belongs to the G protein-coupled receptors family. It is expressed almost exclusively in the anterior pituitary, where it is necessary for somatotroph cells proliferation and for GH synthesis and secretion. Mutations in the human GHRHR gene (GHRHR) can impair ligand binding and signal transduction, and have been estimated to cause about 10% of autosomal recessive familial isolated growth hormone deficiency (IGHD). Mutations reported to date include five splice donor site mutations, two microdeletions, two nonsense mutations, seven missense mutations, and one mutation in the promoter. These mutations have an autosomal recessive mode of inheritance, and heterozygous individuals do not show signs of IGHD, although the presence of an intermediate phenotype has been hypothesized. Conversely, patients with biallelic mutations have low serum insulin-like growth factor-1 and GH levels (with absent or reduced GH response to exogenous stimuli), resulting--if not treated--in proportionate dwarfism. This chapter reviews the biology of the GHRHR, the mutations that affect its gene and their effects in homozygous and heterozygous individuals. Copyright © 2009 Elsevier Inc. All rights reserved.

  11. Medications and impaired driving.

    Science.gov (United States)

    Hetland, Amanda; Carr, David B

    2014-04-01

    To describe the association of specific medication classes with driving outcomes and provide clinical recommendations. The MEDLINE and EMBASE databases were searched for articles published from January 1973 to June 2013 on classes of medications associated with driving impairment. The search included outcome terms such as automobile driving, motor vehicle crash, driving simulator, and road tests. Only English-language articles that contained findings from observational or interventional designs with ≥ 10 participants were included in this review. Cross-sectional studies, case series, and case reports were excluded. Driving is an important task and activity for the majority of adults. Some commonly prescribed medications have been associated with driving impairment measured by road performance, driving simulation, and/or motor vehicle crashes. This review of 30 studies identified findings with barbiturates, benzodiazepines, hypnotics, antidepressants, opioid and nonsteroidal analgesics, anticonvulsants, antipsychotics, antiparkinsonian agents, skeletal muscle relaxants, antihistamines, anticholinergic medications, and hypoglycemic agents. Additional studies of medication impact on sedation, sleep latency, and psychomotor function, as well as the role of alcohol, are also discussed. Psychotropic agents and those with central nervous system side effects were associated with measures of impaired driving performance. It is difficult to determine if such associations are actually a result of medication use or the medical diagnosis itself. Regardless, clinicians should be aware of the increased risk of impaired driving with specific classes of medications, educate their patients, and/or consider safer alternatives.

  12. Clinical and functional characterization of a patient carrying a compound heterozygous pericentrin mutation and a heterozygous IGF1 receptor mutation.

    Directory of Open Access Journals (Sweden)

    Eva Müller

    Full Text Available Intrauterine and postnatal longitudinal growth is controlled by a strong genetic component that regulates a complex network of endocrine factors integrating them with cellular proliferation, differentiation and apoptotic processes in target tissues, particularly the growth centers of the long bones. Here we report on a patient born small for gestational age (SGA with severe, proportionate postnatal growth retardation, discreet signs of skeletal dysplasia, microcephaly and moyamoya disease. Initial genetic evaluation revealed a novel heterozygous IGF1R p.Leu1361Arg mutation affecting a highly conserved residue with the insulin-like growth factor type 1 receptor suggestive for a disturbance within the somatotropic axis. However, because the mutation did not co-segregate with the phenotype and functional characterization did not reveal an obvious impairment of the ligand depending major IGF1R signaling capabilities a second-site mutation was assumed. Mutational screening of components of the somatotropic axis, constituents of the IGF signaling system and factors involved in cellular proliferation, which are described or suggested to provoke syndromic dwarfism phenotypes, was performed. Two compound heterozygous PCNT mutations (p.[Arg585X];[Glu1774X] were identified leading to the specification of the diagnosis to MOPD II. These investigations underline the need for careful assessment of all available information to derive a firm diagnosis from a sequence aberration.

  13. Clinical and functional characterization of a patient carrying a compound heterozygous pericentrin mutation and a heterozygous IGF1 receptor mutation.

    Science.gov (United States)

    Müller, Eva; Dunstheimer, Desiree; Klammt, Jürgen; Friebe, Daniela; Kiess, Wieland; Kratzsch, Jürgen; Kruis, Tassilo; Laue, Sandy; Pfäffle, Roland; Wallborn, Tillmann; Heidemann, Peter H

    2012-01-01

    Intrauterine and postnatal longitudinal growth is controlled by a strong genetic component that regulates a complex network of endocrine factors integrating them with cellular proliferation, differentiation and apoptotic processes in target tissues, particularly the growth centers of the long bones. Here we report on a patient born small for gestational age (SGA) with severe, proportionate postnatal growth retardation, discreet signs of skeletal dysplasia, microcephaly and moyamoya disease. Initial genetic evaluation revealed a novel heterozygous IGF1R p.Leu1361Arg mutation affecting a highly conserved residue with the insulin-like growth factor type 1 receptor suggestive for a disturbance within the somatotropic axis. However, because the mutation did not co-segregate with the phenotype and functional characterization did not reveal an obvious impairment of the ligand depending major IGF1R signaling capabilities a second-site mutation was assumed. Mutational screening of components of the somatotropic axis, constituents of the IGF signaling system and factors involved in cellular proliferation, which are described or suggested to provoke syndromic dwarfism phenotypes, was performed. Two compound heterozygous PCNT mutations (p.[Arg585X];[Glu1774X]) were identified leading to the specification of the diagnosis to MOPD II. These investigations underline the need for careful assessment of all available information to derive a firm diagnosis from a sequence aberration.

  14. Hearing impairment in Estonia

    DEFF Research Database (Denmark)

    Teek, R; Kruustük, K; Zordania, R

    2013-01-01

    Abstract Purpose: The present study was initiated to establish the etiological causes of early onset hearing loss (HL) among Estonian children between 2000-2009. Methods: The study group consisted of 233 probands who were first tested with an arrayed primer extension assay, which covers 199 mutat...... for 115 Estonian patients (49%). This algorithm may be generalized to other populations for clinical application....... performed. Results: In 110 (47%) cases, the etiology of HL was genetic and in 5 (2%) congenital CMV infection was diagnosed. We found mutations with clinical significance in GJB2 (100 children, 43%) and in 2 mitochondrial genes (2 patients, 1%). A single mutation in SLC26A4 gene was detected in 5 probands...... able to conclude that the found abnormalities are definitely pathogenic (12q13.3-q14.2 and 17q22-23.2 microdeletion), but the pathogenity of 2 other findings (3p26.2 and 1p33 microdeletion) remained unknown. Conclusion: This practical diagnostic algorithm confirmed the etiology of early onset HL...

  15. Intellectual Ability in the Duchenne Muscular Dystrophy and Dystrophin Gene Mutation Location

    Directory of Open Access Journals (Sweden)

    Rasic Milic V.

    2014-12-01

    Full Text Available Duchenne muscular dystrophy (DMD is the most common form of muscular dystrophy during childhood. Mutations in dystrophin (DMD gene are also recognized as a cause of cognitive impairment. We aimed to determine the association between intelligence level and mutation location in DMD genes in Serbian patients with DMD. Forty-one male patients with DMD, aged 3 to 16 years, were recruited at the Clinic for Neurology and Psychiatry for Children and Youth in Belgrade, Serbia. All patients had defined DMD gene deletions or duplications [multiplex ligation- dependent probe amplification (MLPA, polymerase chain reaction (PCR] and cognitive status assessment (Wechsler Intelligence Scale for Children, Brunet-Lezine scale, Vineland-Doll scale. In 37 patients with an estimated full scale intelligence quotient (FSIQ, six (16.22% had borderline intelligence (70impaired (FSIQ <70. The FSIQ was not associated with proximal and distal mutations when boundaries were set at exons 30 and 45. However, FSIQ was statistically significantly associated with mutation location when we assumed their functional consequence on dystrophin isoforms and when mutations in the 5’-untranslated region (5’UTR of Dp140 (exons 45-50 were assigned to affect only Dp427 and Dp260. Mutations affecting Dp140 and Dp71/Dp40 have been associated with more frequent and more severe cognitive impairment. Finally, the same classification of mutations explained the greater proportion of FSIQ variability associated with cumulative loss of dystrophin isoforms. In conclusion, cumulative loss of dystrophin isoforms increases the risk of intellectual impairment in DMD and characterizing the genotype can define necessity of early cognitive interventions in DMD patients.

  16. Studies on mutation techniques in rice breeding

    International Nuclear Information System (INIS)

    Wang Cailian; Chen Qiufang; Jin Wei

    2001-01-01

    Synthetical techniques for improving rice mutation breeding efficiency were studied. The techniques consist of corresponding relationship between radiosensitivity and mutation frequency, choosing appropriate materials, combination of physical and chemical mutagens, mutagenic effects of the new mutagenic agents as proton, ions, synchronous irradiation and space mutation. These techniques and methods for inducing mutations are very valuable to increase inducing mutation efficiency and breeding level

  17. Molecular Mechanisms of Glutamine Synthetase Mutations that Lead to Clinically Relevant Pathologies.

    Directory of Open Access Journals (Sweden)

    Benedikt Frieg

    2016-02-01

    Full Text Available Glutamine synthetase (GS catalyzes ATP-dependent ligation of ammonia and glutamate to glutamine. Two mutations of human GS (R324C and R341C were connected to congenital glutamine deficiency with severe brain malformations resulting in neonatal death. Another GS mutation (R324S was identified in a neurologically compromised patient. However, the molecular mechanisms underlying the impairment of GS activity by these mutations have remained elusive. Molecular dynamics simulations, free energy calculations, and rigidity analyses suggest that all three mutations influence the first step of GS catalytic cycle. The R324S and R324C mutations deteriorate GS catalytic activity due to loss of direct interactions with ATP. As to R324S, indirect, water-mediated interactions reduce this effect, which may explain the suggested higher GS residual activity. The R341C mutation weakens ATP binding by destabilizing the interacting residue R340 in the apo state of GS. Additionally, the mutation is predicted to result in a significant destabilization of helix H8, which should negatively affect glutamate binding. This prediction was tested in HEK293 cells overexpressing GS by dot-blot analysis: Structural stability of H8 was impaired through mutation of amino acids interacting with R341, as indicated by a loss of masking of an epitope in the glutamate binding pocket for a monoclonal anti-GS antibody by L-methionine-S-sulfoximine; in contrast, cells transfected with wild type GS showed the masking. Our analyses reveal complex molecular effects underlying impaired GS catalytic activity in three clinically relevant mutants. Our findings could stimulate the development of ATP binding-enhancing molecules by which the R324S mutant can be repaired extrinsically.

  18. Leber's hereditary optic neuropathy is associated with mitochondrial ND1 T3394C mutation

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Min [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Guan, Minqiang [Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhao, Fuxing; Zhou, Xiangtian [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Yuan, Meixia [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Tong, Yi [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian 350005 (China); Yang, Li [Division of Human Genetics, Cincinnati Children' s Hospital Medical Center, 3333 Burnet Avenue, Cincinnati, OH 45229 (United States); Wei, Qi-Ping; Sun, Yan-Hong [Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology, Beijing 100078 (China); Lu, Fan [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Qu, Jia, E-mail: jqu@wzmc.net [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); and others

    2009-06-05

    We report here the clinical, genetic and molecular characterization of four Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age-of-onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T3394C (Y30H) mutation, which localized at a highly conserved tyrosine at position 30 of ND1, and distinct sets of mtDNA polymorphisms belonging to haplogroups D4b and M9a. The occurrence of T3394C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. However, there was the absence of functionally significant mtDNA mutations in these four Chinese pedigrees carrying the T3394C mutation. Therefore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic expression of the LHON-associated T3394C mutation.

  19. Mutation breeding in soybean

    International Nuclear Information System (INIS)

    Baradjanegara, A.A.

    1983-01-01

    In Indonesia, soybean is one of the important crop after rice. It is generally cultivated in the lowlands and rarely in the highlands. Seeds of soybean variety ORBA were treated with various doses of fast neutrons, gamma rays, EMS and NaN 3 with the aims of studying the mutagen effects in M-1 and M-2 generations and also to select mutants adapted to highland conditions. D-50 doses for gamma rays, fast neutrons and EMS were around 23 krad, 2,300 rad, 0.3%, respectively. Much higher chlorophyll mutation frequency was observed in EMS treatment of 0.3%. Seven mutants were shorter and four early mutants matured from 4 to 20 days earlier than the control plants. Two early mutants were quite adaptable in both the low and highlands and produced better yields than the parental material. (author)

  20. Effect of hsm mutations enhancing spontaneous mutability on induced mutagenesis and mitotic recombination in Saccharomyces cerevisiae yeast

    International Nuclear Information System (INIS)

    Fedorova, I.V.; Koval'tsova, S.V.; Ivanov, E.L.

    1993-01-01

    The authors have studied the effect of five nonallelic hms1-hms5 mutations on the incidence of direct mutations in loci ADE1 and ADE2, induced by UV-radiation, 6-hydroxyl-aminopurine, and nitrosomethylurea. All hms mutants were found to be insensitive to the lethal action of these mutagens. The frequency of UV-induced mutations to adenine dependence was increased in mutants hsm2-1, hsm3-1, hsm5-1, and particularly in hsm1-1, but remained unchanged in hsm4-1 compared to HSM. Mutagenesis induced by 6-hydroxylaminopurine was increased in all mutants studied, particularly in mutant hsm3-1. The authors did not detect any appreciable effect of hsm mutations on mutagenesis induced by nitrosomethylurea. The frequency of spontaneous mitotic conversion to prototrophy was studied in diploids heteroallelic to gene ADE2 and homo- and heterozygous for hsm mutations. Mutation hsm5-1 considerably increased the frequency of conversion for all heteroalleles studied, mutations hsm1-1 and hsm3-1 also considerably increased the conversion frequency, while mutations hsm1-1 and hsm4-1 had little effect on this process. The study of the properties of hsm mutations revealed joint genetic control of spontaneous and induced mutagenesis and recombination in yeast. The possibility that hsm mutations belong to the class of mutations impairing correction of unpaired DNA bases is discussed. 25 refs., 3 figs., 3 tabs

  1. Founder Mutations in Xeroderma Pigmentosum

    Science.gov (United States)

    Tamura, Deborah; DiGiovanna, John J.; Kraemer, Kenneth H.

    2012-01-01

    In this issue, Soufir et al. report a founder mutation in the XPC DNA repair gene in 74% of families with xeroderma pigmentosum (XP) in the Maghreb region (Algeria, Morocco, and Tunisia) of northern Africa. These patients have a high frequency of skin cancer. The presence of this founder mutation provides an opportunity for genetic counseling and early diagnosis of XP. PMID:20463673

  2. Mutations causative of familial hypercholesterolaemia

    DEFF Research Database (Denmark)

    Benn, Marianne; Watts, Gerald F; Tybjærg-Hansen, Anne

    2016-01-01

    causing mutations in 98 098 participants from the general population, the Copenhagen General Population Study. METHODS AND RESULTS: We genotyped for LDLR[W23X;W66G;W556S] and APOB[R3500Q] accounting for 38.7% of pathogenic FH mutations in Copenhagen. Clinical FH assessment excluded mutation information......-cholesterol concentration to discriminate between mutation carriers and non-carriers was 4.4 mmol/L. CONCLUSION: Familial hypercholesterolaemia-causing mutations are estimated to occur in 1:217 in the general population and are best identified by a definite or probable phenotypic diagnosis of FH based on the DLCN criteria....... The prevalence of the four FH mutations was 0.18% (1:565), suggesting a total prevalence of FH mutations of 0.46% (1:217). Using the Dutch Lipid Clinic Network (DLCN) criteria, odds ratios for an FH mutation were 439 (95% CI: 170-1 138) for definite FH, 90 (53-152) for probable FH, and 18 (13-25) for possible FH...

  3. Grammatical Impairments in PPA.

    Science.gov (United States)

    Thompson, Cynthia K; Mack, Jennifer E

    2014-09-01

    Grammatical impairments are commonly observed in the agrammatic subtype of primary progressive aphasia (PPA-G), whereas grammatical processing is relatively preserved in logopenic (PPA-L) and semantic (PPA-S) subtypes. We review research on grammatical deficits in PPA and associated neural mechanisms, with discussion focused on production and comprehension of four aspects of morphosyntactic structure: grammatical morphology, functional categories, verbs and verb argument structure, and complex syntactic structures. We also address assessment of grammatical deficits in PPA, with emphasis on behavioral tests of grammatical processing. Finally, we address research examining the effects of treatment for progressive grammatical impairments. PPA-G is associated with grammatical deficits that are evident across linguistic domains in both production and comprehension. PPA-G is associated with damage to regions including the left inferior frontal gyrus (IFG) and dorsal white matter tracts, which have been linked to impaired comprehension and production of complex sentences. Detailing grammatical deficits in PPA is important for estimating the trajectory of language decline and associated neuropathology. We, therefore, highlight several new assessment tools for examining different aspects of morphosyntactic processing in PPA. Individuals with PPA-G present with agrammatic deficit patterns distinct from those associated with PPA-L and PPA-S, but similar to those seen in agrammatism resulting from stroke, and patterns of cortical atrophy and white matter changes associated with PPA-G have been identified. Methods for clinical evaluation of agrammatism, focusing on comprehension and production of grammatical morphology, functional categories, verbs and verb argument structure, and complex syntactic structures are recommended and tools for this are emerging in the literature. Further research is needed to investigate the real-time processes underlying grammatical impairments in

  4. Leber's hereditary optic neuropathy is associated with mitochondrial ND6 T14502C mutation

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Fuxin [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Guan, Minqiang [Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhou, Xiangtian [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Yuan, Meixia; Liang, Ming [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Liu, Qi [Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Liu, Yan; Zhang, Yongmei [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Yang, Li [Division of Human Genetics, Cincinnati Children' s Hospital Medical Center, Cincinnati, OH 45229 (United States); Tong, Yi [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); The First Affiliated Hospital, Fujian Medical University, Fuzhou, Fujian 350005 (China); Wei, Qi-Ping; Sun, Yan-Hong [Department of Ophthalmology, Dongfang Hospital, Beijing University of Chinese Medicine and Pharmacology, Beijing 100078 (China); Qu, Jia, E-mail: jqu@wzmc.net [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou, Zhejiang 325003 (China); and others

    2009-11-20

    We report here the clinical, genetic, and molecular characterization of three Chinese families with Leber's hereditary optic neuropathy (LHON). There were variable severity and age of onset in visual impairment among these families. Strikingly, there were extremely low penetrances of visual impairment in these Chinese families. Sequence analysis of complete mitochondrial genomes in these pedigrees showed the homoplasmic T14502C (I58V) mutation, which localized at a highly conserved isoleucine at position 58 of ND6, and distinct sets of mtDNA polymorphisms belonging to haplogroups M10a, F1a1, and H2. The occurrence of T14502C mutation in these several genetically unrelated subjects affected by visual impairment strongly indicates that this mutation is involved in the pathogenesis of visual impairment. Here, mtDNA variants I187T in the ND1, A122V in CO1, S99A in the A6, and V254I in CO3 exhibited an evolutionary conservation, indicating a potential modifying role in the development of visual impairment associated with T14502C mutation in those families. Furthermore, nuclear modifier gene(s) or environmental factor(s) may play a role in the phenotypic manifestation of the LHON-associated T14502C mutation in these Chinese families.

  5. The ABCA4 2588G>C Stargardt mutation: single origin and increasing frequency from South-West to North-East Europe.

    NARCIS (Netherlands)

    Maugeri, A.; Flothmann, K.; Hemmrich, N.; Ingvast, S.; Jorge, P.; Paloma, E.; Patel, R.; Rozet, J.M.; Tammur, J.; Testa, F.; Balcells, S.; Bird, A.C.; Brunner, H.G.; Hoyng, C.B.; Metspalu, A.; Simonelli, F.; Allikmets, R.; Bhattacharya, S.S.; Urso, M. D'; Gonzalez-Duarte, R.; Kaplan, J.; Meerman, G.J. te; Santos, R.L.; Schwartz, M.; Camp, G. van; Wadelius, C.; Weber, B.; Cremers, F.P.M.

    2002-01-01

    Inherited retinal dystrophies represent the most important cause of vision impairment in adolescence, affecting approximately 1 out of 3000 individuals. Mutations of the photoreceptor-specific gene ABCA4 (ABCR) are a common cause of retinal dystrophy. A number of mutations have been repeatedly

  6. The ABCA4 2588G > C Stargardt mutation : Single origin and increasing frequency from South-West to North-East Europe

    NARCIS (Netherlands)

    Maugeri, A; Flothmann, K; Hemmrich, N; Ingvast, S; Jorge, P; Paloma, E; Patel, R; Rozet, JM; Tammur, J; Testa, F; Balcells, S; Bird, AC; Brunner, HG; Hoyng, CB; Metspalu, A; Simonelli, F; Allikmets, R; Bhattacharya, SS; D'Urso, M; Gonzalez-Duarte, R; Kaplan, J; Meerman, GJT; Santoss, R; Schwartz, M; Van Camp, G; Wadelius, C; Weber, BHF; Cremers, FPM

    Inherited retinal dystrophies represent the most important cause of vision impairment in adolescence, affecting approximately 1 out of 3000 individuals. Mutations of the photoreceptor-specific gene ABCA4 (ABCR) are a common cause of retinal dystrophy. A number of mutations have been repeatedly

  7. Clinical presentation of atopic dermatitis by filaggrin gene mutation status during the first 7 years of life in a prospective cohort study

    DEFF Research Database (Denmark)

    Giwercman, Charlotte; Rasmussen, Morten Arendt; Thyssen, Jacob B.

    2012-01-01

    Filaggrin null mutations result in impaired skin barrier functions, increase the risk of early onset atopic dermatitis and lead to a more severe and chronic disease. We aimed to characterize the clinical presentation and course of atopic dermatitis associated with filaggrin mutations within...

  8. MPL mutations in myeloproliferative disorders

    DEFF Research Database (Denmark)

    Beer, Philip A.; Campbell, Peter J.; Scott, Linda M.

    2008-01-01

    Activating mutations of MPL exon 10 have been described in a minority of patients with idiopathic myelofibrosis (IMF) or essential thrombocythemia (ET), but their prevalence and clinical significance are unclear. Here we demonstrate that MPL mutations outside exon 10 are uncommon in platelet c......DNA and identify 4 different exon 10 mutations in granulocyte DNA from a retrospective cohort of 200 patients with ET or IMF. Allele-specific polymerase chain reaction was then used to genotype 776 samples from patients with ET entered into the PT-1 studies. MPL mutations were identified in 8.5% of JAK2 V617F......(-) patients and a single V617F(+) patient. Patients carrying the W515K allele had a significantly higher allele burden than did those with the W515L allele, suggesting a functional difference between the 2 variants. Compared with V617F(+) ET patients, those with MPL mutations displayed lower hemoglobin...

  9. Mutation induction by heavy ions

    Science.gov (United States)

    Kiefer, J.; Stoll, U.; Schneider, E.

    1994-10-01

    Mutation induction by heavy ions is compared in yeast and mammalian cells. Since mutants can only be recovered in survivors the influence of inactivation cross sections has to be taken into account. It is shown that both the size of the sensitive cellular site as well as track structure play an important role. Another parameter which influences the probability of mutation induction is repair: Contrary to naive assumptions primary radiation damage does not directly lead to mutations but requires modification to reconstitute the genetic machinery so that mutants can survive. The molecular structure of mutations was analyzed after exposure to deuterons by amplification with the aid of polymerase chain reaction. The results-although preliminary-demonstrate that even with densely ionizing particles a large fraction does not carry big deletions which suggests that point mutations may also be induced by heavy ions.

  10. Mutation breeding in ornamental plants

    International Nuclear Information System (INIS)

    Datta, S.K.

    1990-01-01

    Full text: Mutation induction produced a large number of new promising varieties in ornamental species. 37 new mutants of Chrysanthemum and 14 of rose have been developed by mutations and released for commercialisation. The mutations in flower colour/shape were detected as chimeras in M 1 V 1 , M 1 V 2 , M 1 V 3 generations. The mutation frequency varied with the cultivar and exposure to gamma rays. Comparative analysis of original cultivars and their respective induced mutants on cytomorphological, anatomical and biochemical characters are being carried out for better understanding of the mechanism involved in the origin and evolution of somatic flower colour/shape mutations. Cytological analysis with reference to chromosomal aberrations, chromosome number, ICV, INV and DNA content gave no differences between the original and mutant cultivars. Analysis of florets/petal pigments by TLC and spectrophotometric methods indicated both qualitative and quantitative changes. (author)

  11. Working with impairments

    OpenAIRE

    Maroesjka Versantvoort; Patricia van Echtelt

    2012-01-01

    Original title: Belemmerd aan het werk The Netherlands was long known as a country with high sickness absenteeism rates and a burgeoning group of people who were unfit for work. In response to this, many policy measures have been introduced in recent decades which attempt to limit the benefit volume and foster the reintegration of people with health impairments. What is the position of the Netherlands today in this regard? The main trends in sickness absenteeism, degree of incapacity for work...

  12. Mutational meltdown in laboratory yeast populations

    NARCIS (Netherlands)

    Zeyl, C.; Mizesko, M.; Visser, de J.A.G.M.

    2001-01-01

    In small or repeatedly bottlenecked populations, mutations are expected to accumulate by genetic drift, causing fitness declines. In mutational meltdown models, such fitness declines further reduce population size, thus accelerating additional mutation accumulation and leading to extinction. Because

  13. Age-Related Sensory Impairments and Risk of Cognitive Impairment

    Science.gov (United States)

    Fischer, Mary E; Cruickshanks, Karen J.; Schubert, Carla R; Pinto, Alex A; Carlsson, Cynthia M; Klein, Barbara EK; Klein, Ronald; Tweed, Ted S.

    2016-01-01

    Background/Objectives To evaluate the associations of sensory impairments with the 10-year risk of cognitive impairment. Previous work has primarily focused on the relationship between a single sensory system and cognition. Design The Epidemiology of Hearing Loss Study (EHLS) is a longitudinal, population-based study of aging in the Beaver Dam, WI community. Baseline examinations were conducted in 1993 and follow-up exams have been conducted every 5 years. Setting General community Participants EHLS members without cognitive impairment at EHLS-2 (1998–2000). There were 1,884 participants (mean age = 66.7 years) with complete EHLS-2 sensory data and follow-up information. Measurements Cognitive impairment was a Mini-Mental State Examination score of impairment was a pure-tone average of hearing thresholds (0.5, 1, 2 and 4 kHz) of > 25 decibel Hearing Level in either ear. Visual impairment was Pelli-Robson contrast sensitivity of impairment was a San Diego Odor Identification Test score of impairment were independently associated with cognitive impairment risk [Hearing: Hazard Ratio (HR) = 1.90, 95% Confidence Interval (C.I.) = 1.11, 3.26; Vision: HR = 2.05, 95% C.I. = 1.24, 3.38; Olfaction: HR = 3.92, 95% C.I. = 2.45, 6.26]. However, 85% with hearing impairment, 81% with visual impairment, and 76% with olfactory impairment did not develop cognitive impairment during follow-up. Conclusion The relationship between sensory impairment and cognitive impairment was not unique to one sensory system suggesting sensorineural health may be a marker of brain aging. The development of a combined sensorineurocognitive measure may be useful in uncovering mechanisms of healthy brain aging. PMID:27611845

  14. A case report on ATP6V0A4 gene mutation: Forecast of familial ...

    African Journals Online (AJOL)

    ... screening of recessive forms of dRTA independent of hearing status and offer suitable intervention to treat dRTA as well as diminish the influence of SNHL on the child's learning and communication in daily life. Keywords: Renal tubular acidosis, Homeostasis, Electrolytes, Hearing impairment, ATP6V0A4 gene, Mutation ...

  15. Endophilin mutations block clathrin-mediated endocytosis but not neurotransmitter release

    DEFF Research Database (Denmark)

    Verstreken, Patrik; Kjaerulff, Ole; Lloyd, Thomas E

    2002-01-01

    We have identified mutations in Drosophila endophilin to study its function in vivo. Endophilin is required presynaptically at the neuromuscular junction, and absence of Endophilin dramatically impairs endocytosis in vivo. Mutant larvae that lack Endophilin fail to take up FM1-43 dye in synaptic ...

  16. USH2A mutation analysis in 70 Dutch families with Usher syndrome type II.

    NARCIS (Netherlands)

    Pennings, R.J.E.; Brinke, H. te; Weston, M.D.; Claassen, A.M.W.; Orten, D.J.; Weekamp, H.; Aarem, A. van; Huygen, P.L.M.; Deutman, A.F.; Hoefsloot, L.H.; Cremers, F.P.M.; Cremers, C.W.R.J.; Kimberling, W.J.; Kremer, J.M.J.

    2004-01-01

    Usher syndrome type II (USH2) is characterised by moderate to severe high-frequency hearing impairment, progressive visual loss due to retinitis pigmentosa and intact vestibular responses. Three loci are known for USH2, however, only the gene for USH2a (USH2A) has been identified. Mutation analysis

  17. Autosomal dominant SCN8A mutation with an unusually mild phenotype.

    Science.gov (United States)

    Anand, G; Collett-White, F; Orsini, A; Thomas, S; Jayapal, S; Trump, N; Zaiwalla, Z; Jayawant, S

    2016-09-01

    Mutations in SCN8A, coding for the voltage-gated sodium channel Nav 1.6, have been described in relation to infantile onset epilepsy with developmental delay and cognitive impairment, in particular early onset epileptic encephalopathy (EIEE) type 13. Here we report an infant and his father with early onset focal epileptic seizures but without cognitive or neurological impairment in whom next generation sequence analysis identified a heterozygous mutation (c.5630A > G, p. (Asn1877Ser)) in the SCN8A gene. This mutation, confirmed by Sanger sequence analysis, affects a highly conserved amino acid and in silico tools predicts that it may be pathogenic. The reported infant has a normal developmental profile at 16-month follow-up. His father also had normal development and has no cognitive impairment at 42 years. This is the second known SCN8A mutation associated with a phenotype of benign familial infantile epilepsy. Good seizure control was achieved in our patients with sodium channel blockers. Based on our proband and a recently described group of families with benign familial infantile epilepsy and SCN8A variant we suggest expanding testing to patients with infantile epilepsy and no cognitive impairment. In addition, the same SCN8A variant (c.5630A > G, p. (Asn1877Ser)) is also found in patients with epilepsy and developmental delay highlighting the phenotypic variability and the possible role of other protective genetic factors. Copyright © 2016. Published by Elsevier Ltd.

  18. Brody disease: insights into biochemical features of SERCA1 and identification of a novel mutation.

    NARCIS (Netherlands)

    Vattemi, G.; Gualandi, F.; Oosterhof, A.; Marini, M.; Tonin, P.; Rimessi, P.; Neri, M.; Guglielmi, V.; Russignan, A.; Poli, C.; Kuppevelt, A.H.M.S.M. van; Ferlini, A.; Tomelleri, G.

    2010-01-01

    Brody disease is an inherited disorder of skeletal muscle function characterized by increasing impairment of relaxation during exercise. The autosomal recessive form can be caused by mutations in the ATP2A1 gene, which encodes for the sarcoplasmic/endoplasmic reticulum Ca-ATPase 1 (SERCA1) protein.

  19. Assessment of Hearing Impaired Youth.

    Science.gov (United States)

    Hicks, Doin E., Ed.; And Others

    1980-01-01

    The issue of Directions contains 11 articles on assessment of hearing impaired individuals. Entries have the following titles and authors: "Classroom Assessment Techniques for Hearing Impaired Students--A Literature Review" (B. McKee, M. Hausknecht); "Informal Assessment of Hearing Impaired Students In the Classroom" (B. Culhane, R. Hein);…

  20. Gradual Loss of ACTH Due to a Novel Mutation in LHX4: Comprehensive Mutation Screening in Japanese Patients with Congenital Hypopituitarism

    Science.gov (United States)

    Takagi, Masaki; Ishii, Tomohiro; Inokuchi, Mikako; Amano, Naoko; Narumi, Satoshi; Asakura, Yumi; Muroya, Koji; Hasegawa, Yukihiro; Adachi, Masanori; Hasegawa, Tomonobu

    2012-01-01

    Mutations in transcription factors genes, which are well regulated spatially and temporally in the pituitary gland, result in congenital hypopituitarism (CH) in humans. The prevalence of CH attributable to transcription factor mutations appears to be rare and varies among populations. This study aimed to define the prevalence of CH in terms of nine CH-associated genes among Japanese patients. We enrolled 91 Japanese CH patients for DNA sequencing of POU1F1, PROP1, HESX1, LHX3, LHX4, SOX2, SOX3, OTX2, and GLI2. Additionally, gene copy numbers for POU1F1, PROP1, HESX1, LHX3, and LHX4 were examined by multiplex ligation-dependent probe amplification. The gene regulatory properties of mutant LHX4 proteins were characterized in vitro. We identified two novel heterozygous LHX4 mutations, namely c.249-1G>A, p.V75I, and one common POU1F1 mutation, p.R271W. The patient harboring the c.249-1G>A mutation exhibited isolated growth hormone deficiency at diagnosis and a gradual loss of ACTH, whereas the patient with the p.V75I mutation exhibited multiple pituitary hormone deficiency. In vitro experiments showed that both LHX4 mutations were associated with an impairment of the transactivation capacities of POU1F1 andαGSU, without any dominant-negative effects. The total mutation prevalence in Japanese CH patients was 3.3%. This study is the first to describe, a gradual loss of ACTH in a patient carrying an LHX4 mutation. Careful monitoring of hypothalamic–pituitary -adrenal function is recommended for CH patients with LHX4 mutations. PMID:23029363

  1. GRIN1 mutations cause encephalopathy with infantile-onset epilepsy, and hyperkinetic and stereotyped movement disorders.

    Science.gov (United States)

    Ohba, Chihiro; Shiina, Masaaki; Tohyama, Jun; Haginoya, Kazuhiro; Lerman-Sagie, Tally; Okamoto, Nobuhiko; Blumkin, Lubov; Lev, Dorit; Mukaida, Souichi; Nozaki, Fumihito; Uematsu, Mitsugu; Onuma, Akira; Kodera, Hirofumi; Nakashima, Mitsuko; Tsurusaki, Yoshinori; Miyake, Noriko; Tanaka, Fumiaki; Kato, Mitsuhiro; Ogata, Kazuhiro; Saitsu, Hirotomo; Matsumoto, Naomichi

    2015-06-01

    Recently, de novo mutations in GRIN1 have been identified in patients with nonsyndromic intellectual disability and epileptic encephalopathy. Whole exome sequencing (WES) analysis of patients with genetically unsolved epileptic encephalopathies identified four patients with GRIN1 mutations, allowing us to investigate the phenotypic spectrum of GRIN1 mutations. Eighty-eight patients with unclassified early onset epileptic encephalopathies (EOEEs) with an age of onset stereotypic hand movements were observed in two and three patients, respectively. All the four patients exhibited only nonspecific focal and diffuse epileptiform abnormality, and never showed suppression-burst or hypsarrhythmia during infancy. A de novo mosaic mutation (c.1923G>A) with a mutant allele frequency of 16% (in DNA of blood leukocytes) was detected in one patient. Three mutations were located in the transmembrane domain (3/4, 75%), and one in the extracellular loop near transmembrane helix 1. All the mutations were predicted to impair the function of the NMDA receptor. Clinical features of de novo GRIN1 mutations include infantile involuntary movements, seizures, and hand stereotypies, suggesting that GRIN1 mutations cause encephalopathy resulting in seizures and movement disorders. Wiley Periodicals, Inc. © 2015 International League Against Epilepsy.

  2. Minisequencing mitochondrial DNA pathogenic mutations

    Directory of Open Access Journals (Sweden)

    Carracedo Ángel

    2008-04-01

    Full Text Available Abstract Background There are a number of well-known mutations responsible of common mitochondrial DNA (mtDNA diseases. In order to overcome technical problems related to the analysis of complete mtDNA genomes, a variety of different techniques have been proposed that allow the screening of coding region pathogenic mutations. Methods We here propose a minisequencing assay for the analysis of mtDNA mutations. In a single reaction, we interrogate a total of 25 pathogenic mutations distributed all around the whole mtDNA genome in a sample of patients suspected for mtDNA disease. Results We have detected 11 causal homoplasmic mutations in patients suspected for Leber disease, which were further confirmed by standard automatic sequencing. Mutations m.11778G>A and m.14484T>C occur at higher frequency than expected by change in the Galician (northwest Spain patients carrying haplogroup J lineages (Fisher's Exact test, P-value Conclusion We here developed a minisequencing genotyping method for the screening of the most common pathogenic mtDNA mutations which is simple, fast, and low-cost. The technique is robust and reproducible and can easily be implemented in standard clinical laboratories.

  3. Mutation breeding in malting barley

    Energy Technology Data Exchange (ETDEWEB)

    Hiraki, Makoto; Sanada, Matsuyoshi

    1984-03-01

    The released varieties of malting barley through mutation breeding is more than ten in number, including foreign varieties. In Japan four varieties has been released so far. We started mutation breeding in 1956 together with cross breeding that we employed before. Until now, Gamma 4, Amagi Nijo 1 and Fuji Nijo 2 have been produced from the direct use of induced mutations and Nirasaki Nijo 8 from the indirect use of them. Mutation breeding has been used mainly in the partial improvement of agronomic characteristics since the selection for malting quality was very complicated. As the variety bred by induced mutation is usually equivalent to the original variety in malting quality, both this new variety and the original one could be cultivated in the same area without any problem on later malt production. Particularly when one farmer cultivates barley in an extensive acreage, he can harvest at the best time according to the different maturing time of each variety. From these points of view, mutation breeding is an efficient tool in malting barley breeding. Mutagens we have used so far are X-rays, ..gamma..-rays, neutron and chemicals such as dES. From our experience in selection, the low dose of radiation and chemical mutagens are more effective in selection of point mutation than the high dose of radiation which tends to produce many abnormal but few practical mutants. (author).

  4. HNPCC: Six new pathogenic mutations

    Directory of Open Access Journals (Sweden)

    Epplen Joerg T

    2004-06-01

    Full Text Available Abstract Background Hereditary non-polyposis colorectal cancer (HNPCC is an autosomal dominant disease with a high risk for colorectal and endometrial cancer caused by germline mutations in DNA mismatch-repair genes (MMR. HNPCC accounts for approximately 2 to 5% of all colorectal cancers. Here we present 6 novel mutations in the DNA mismatch-repair genes MLH1, MSH2 and MSH6. Methods Patients with clinical diagnosis of HNPCC were counselled. Tumor specimen were analysed for microsatellite instability and immunohistochemistry for MLH1, MSH2 and MSH6 protein was performed. If one of these proteins was not detectable in the tumor mutation analysis of the corresponding gene was carried out. Results We identified 6 frameshift mutations (2 in MLH1, 3 in MSH2, 1 in MSH6 resulting in a premature stop: two mutations in MLH1 (c.2198_2199insAACA [p.N733fsX745], c.2076_2077delTG [p.G693fsX702], three mutations in MSH2 (c.810_811delGT [p.C271fsX282], c.763_766delAGTGinsTT [p.F255fsX282], c.873_876delGACT [p.L292fsX298] and one mutation in MSH6 (c.1421_1422dupTG [p.C475fsX480]. All six tumors tested for microsatellite instability showed high levels of microsatellite instability (MSI-H. Conclusions HNPCC in families with MSH6 germline mutations may show an age of onset that is comparable to this of patients with MLH1 and MSH2 mutations.

  5. Factor V Leiden Mutation and PT 20210 Mutation Test

    Science.gov (United States)

    ... Disorders Fibromyalgia Food and Waterborne Illness Fungal Infections Gout Graves Disease Guillain-Barré Syndrome Hashimoto Thyroiditis Heart ... Tested? To determine whether you have an inherited gene mutation that increases your risk of developing a ...

  6. Mutations induced by ultraviolet light

    International Nuclear Information System (INIS)

    Pfeifer, Gerd P.; You, Young-Hyun; Besaratinia, Ahmad

    2005-01-01

    The different ultraviolet (UV) wavelength components, UVA (320-400 nm), UVB (280-320 nm), and UVC (200-280 nm), have distinct mutagenic properties. A hallmark of UVC and UVB mutagenesis is the high frequency of transition mutations at dipyrimidine sequences containing cytosine. In human skin cancers, about 35% of all mutations in the p53 gene are transitions at dipyrimidines within the sequence 5'-TCG and 5'-CCG, and these are localized at several mutational hotspots. Since 5'-CG sequences are methylated along the p53 coding sequence in human cells, these mutations may be derived from sunlight-induced pyrimidine dimers forming at sequences that contain 5-methylcytosine. Cyclobutane pyrimidine dimers (CPDs) form preferentially at dipyrimidines containing 5-methylcytosine when cells are irradiated with UVB or sunlight. In order to define the contribution of 5-methylcytosine to sunlight-induced mutations, the lacI and cII transgenes in mouse fibroblasts were used as mutational targets. After 254 nm UVC irradiation, only 6-9% of the base substitutions were at dipyrimidines containing 5-methylcytosine. However, 24-32% of the solar light-induced mutations were at dipyrimidines that contain 5-methylcytosine and most of these mutations were transitions. Thus, CPDs forming preferentially at dipyrimidines with 5-methylcytosine are responsible for a considerable fraction of the mutations induced by sunlight in mammalian cells. Using mouse cell lines harboring photoproduct-specific photolyases and mutational reporter genes, we showed that CPDs (rather than 6-4 photoproducts or other lesions) are responsible for the great majority of UVB-induced mutations. An important component of UVB mutagenesis is the deamination of cytosine and 5-methylcytosine within CPDs. The mutational specificity of long-wave UVA (340-400 nm) is distinct from that of the shorter wavelength UV and is characterized mainly by G to T transversions presumably arising through mechanisms involving oxidized DNA

  7. Radiation mutation breeding

    International Nuclear Information System (INIS)

    Song, Hi Sup; Kim, Jae Sung; Kim, Jin Kyu; Shin, In Chul; Lim, Young Taek

    1998-04-01

    In order to develop an advanced technical knowledge for the selection of better mutants, some of the crops were irradiated and the mutation rate, the survival rate and the method for selction of a mutant were studied. Furthermore, this study aimed to obtain basic data applicable to the development of genetic resources by evaluation and analysis the specific character for selection of the superior mutant and its plant breeding. 1. selection of the mutant with a superior resistance against environment in the principal crops 1) New varieties of mutant rices such as Wonpyeongbyeo, Wongwangbyeo, Winmibyeo, and heogseon chalbeyeo (sticky forma) were registered in the national variety list and made an application to crop variety protection right. They are under review now. 2) We also keep on studying on the number of a grain of 8 lines of excellent mutant rice for the purpose of improvement of breeding . 3) We selected 3 lines which have a resistance to pod and stem blight in large soybean, 31 lines with small grain size and higher yield, 112 lines of soybean of cooking, 7 lines of low lipoxygenase content, and 12 lines with decreased phytic acid content by 20 % compared to the previous level. 2. Selection of advanced Mugunwha (Rose of Sharon) mutant 1) Bagseul, a new variety of mutant, was developed and 30 plantlets of it are being proliferated. 2) Fifty-three lines of a mutant having a various morphologies were selected

  8. Radiation mutation breeding

    Energy Technology Data Exchange (ETDEWEB)

    Song, Hi Sup; Kim, Jae Sung; Kim, Jin Kyu; Shin, In Chul; Lim, Young Taek

    1998-04-01

    In order to develop an advanced technical knowledge for the selection of better mutants, some of the crops were irradiated and the mutation rate, the survival rate and the method for selction of a mutant were studied. Furthermore, this study aimed to obtain basic data applicable to the development of genetic resources by evaluation and analysis the specific character for selection of the superior mutant and its plant breeding. 1. selection of the mutant with a superior resistance against environment in the principal crops 1) New varieties of mutant rices such as Wonpyeongbyeo, Wongwangbyeo, Winmibyeo, and heogseon chalbeyeo (sticky forma) were registered in the national variety list and made an application to crop variety protection right. They are under review now. 2) We also keep on studying on the number of a grain of 8 lines of excellent mutant rice for the purpose of improvement of breeding . 3) We selected 3 lines which have a resistance to pod and stem blight in large soybean, 31 lines with small grain size and higher yield, 112 lines of soybean of cooking, 7 lines of low lipoxygenase content, and 12 lines with decreased phytic acid content by 20 % compared to the previous level. 2. Selection of advanced Mugunwha (Rose of Sharon) mutant 1) Bagseul, a new variety of mutant, was developed and 30 plantlets of it are being proliferated. 2) Fifty-three lines of a mutant having a various morphologies were selected.

  9. Mutation breeding in wheat

    International Nuclear Information System (INIS)

    Amer, I.M.

    2002-01-01

    The study aims to improve the productivity of wheat by using gamma ray (100 - 600 Gy) in mutation breading. Five local varieties were used and the program continued for the Sakha 69 for seven generations. Seeds irradiated with 600 Gy were not germinated in the field, while low doses (100-150 Gy) stimulated the root growth and spike length. The higher doses caused gradual decrease of growth with differences in varieties response. in the second generation, a genetic differences were noticed in most varieties using doses of 100-300 Gy, and the dispike was disappeared when 250 Gy was used. 79 plants from irradiated Sakha 69 were selected according to spike length and the number of grains and planted with the control to test the third generation. differences between the varieties were noticed and 8 mutants with high productivity were selected and evaluated in the fourth and fifth generations with the local variety. The mutants improve the productivity and in particular the mutants Nos.. (19-1), (14-3), and (30-2). The experiment showed the relation between the planting sites and the mutants in the sixth and seven generations

  10. Induced mutations in castor

    International Nuclear Information System (INIS)

    Ganesan, K.; Javad Hussain, H.S.; Vindhiyavarman, P.

    2001-01-01

    Castor (Ricinus communis L.) is an important oilseed crop in India. To create variability mutations were induced in two cultivars 'TMV5' (maturing in 130-140 days) and 'CO1' (perennial type). Gamma rays and diethyl sulphate and ethidium bromide were used for seed treatment. Ten doses, from 100 to 1000 Gy were employed. For chemical mutagenesis five concentrations of mutagenes from 10 to 50 mM were tried. No economic mutants could be isolated after treatment with the chemical mutagens. The following economic mutants were identified in the dose 300 Gy of gamma rays. Annual types from perennial CO 1 castor CO 1 is a perennial variety (8-10 years) with bold seeds (100 seed weight 90 g) and high oil content (57%). Twenty-one lines were isolated with annual types (160-180 days) with high yield potential as well as bold seeds and high oil content. These mutants, identified in M 3 generation were bred true in subsequent generations up to M 8 generation. Critical evaluation of the mutants in yield evaluation trials is in progress

  11. Novel allelic mutations in murine Serca2 induce differential development of squamous cell tumors

    Energy Technology Data Exchange (ETDEWEB)

    Toki, Hideaki; Minowa, Osamu; Inoue, Maki; Motegi, Hiromi; Karashima, Yuko; Ikeda, Ami [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Kaneda, Hideki [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Sakuraba, Yoshiyuki [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Saiki, Yuriko [Department of Molecular Pathology, Tohoku University Graduate School of Medicine, Sendai, Miyagi (Japan); Wakana, Shigeharu [Technology and Development Team for Mouse Phenotype Analysis, Riken BRC, Tsukuba, Ibaraki (Japan); Suzuki, Hiroshi [Department of Biochemistry, Asahikawa Medical University, Asahikawa, Hokkaido (Japan); Gondo, Yoichi [Mutagenesis and Genomics Team, Riken BRC, Tsukuba, Ibaraki (Japan); Shiroishi, Toshihiko [Mammalian Genetics Laboratory, National Institute of Genetics, Mishima, Shizuoka (Japan); Noda, Tetsuo, E-mail: tnoda@jfcr.or.jp [Team for Advanced Development and Evaluation of Human Disease Models, Riken BioResource Center (BRC), Tsukuba, Ibaraki (Japan); Department of Cell Biology, Cancer Institute, The Japanese Foundation for Cancer Research, Tokyo (Japan)

    2016-08-05

    Dominant mutations in the Serca2 gene, which encodes sarco(endo)plasmic reticulum calcium-ATPase, predispose mice to gastrointestinal epithelial carcinoma [1–4] and humans to Darier disease (DD) [14–17]. In this study, we generated mice harboring N-ethyl-N-nitrosourea (ENU)-induced allelic mutations in Serca2: three missense mutations and one nonsense mutation. Mice harboring these Serca2 mutations developed tumors that were categorized as either early onset squamous cell tumors (SCT), with development similar to null-type knockout mice [2,4] (aggressive form; M682, M814), or late onset tumors (mild form; M1049, M1162). Molecular analysis showed no aberration in Serca2 mRNA or protein expression levels in normal esophageal cells of any of the four mutant heterozygotes. There was no loss of heterozygosity at the Serca2 locus in the squamous cell carcinomas in any of the four lines. The effect of each mutation on Ca{sup 2+}-ATPase activity was predicted using atomic-structure models and accumulated mutated protein studies, suggesting that putative complete loss of Serca2 enzymatic activity may lead to early tumor onset, whereas mutations in which Serca2 retains residual enzymatic activity result in late onset. We propose that impaired Serca2 gene product activity has a long-term effect on squamous cell carcinogenesis from onset to the final carcinoma stage through an as-yet unrecognized but common regulatory pathway. -- Highlights: •Novel mutations in murine Serca2 caused early onset or late onset of tumorigenesis. •They also caused higher or lower incidence of Darier Disease phenotype. •3D structure model suggested the former mutations led to severer defect on ATPase. •Driver gene mutations via long-range effect on Ca2+ distributions are suggested.

  12. Mutations in the glucocerebrosidase gene are common in patients with Parkinson's disease from Eastern Canada.

    Science.gov (United States)

    Han, Fabin; Grimes, David A; Li, Fang; Wang, Ting; Yu, Zhe; Song, Na; Wu, Shichao; Racacho, Lemuel; Bulman, Dennis E

    2016-01-01

    Mutations in the β-glucocerebrosidase gene (GBA) have been implicated as a risk factor for Parkinson's disease (PD). However, GBA mutations in PD patients of different ethnic origins were reported to be inconsistent. We sequenced all exons of the GBA gene in 225 PD patients and 110 control individuals from Eastern Canada. Two novel GBA variants of c.-119 A/G and S(-35)N, five known GBA mutations of R120W, N370S, L444P, RecNciI and RecTL mutation (del55/D409H/RecNciI) as well as two non-pathological variants of E326K and T369M were identified from PD patients while only one mutation of S13L and two non-pathological variants of E326K and T369M were found in the control individuals. The frequency of GBA mutations within PD patients (4.4%) is 4.8 times higher than the 0.91% observed in control individuals (X(2) = 2.91, p = 0.088; odds ratio = 4.835; 95% confidence interval = 2.524-9.123). The most common mutations of N370S and L444P accounted for 36.0% (9/25) of all the GBA mutations in this Eastern Canadian PD cohort. The frequency (6.67%) of E326K and T369M in PD patients is comparable to 7.27% in control individuals (X(2) = 0.042, p = 0.8376), further supporting that these two variants have no pathological effects on PD. Phenotype analysis showed that no significant difference in family history, age at onset and cognitive impairment was identified between the GBA mutation carriers and non-GBA mutation carriers. GBA mutations were found to be a common genetic risk factor for PD in Eastern Canadian patients.

  13. FGFR3 mutation causes abnormal membranous ossification in achondroplasia.

    Science.gov (United States)

    Di Rocco, Federico; Biosse Duplan, Martin; Heuzé, Yann; Kaci, Nabil; Komla-Ebri, Davide; Munnich, Arnold; Mugniery, Emilie; Benoist-Lasselin, Catherine; Legeai-Mallet, Laurence

    2014-06-01

    FGFR3 gain-of-function mutations lead to both chondrodysplasias and craniosynostoses. Achondroplasia (ACH), the most frequent dwarfism, is due to an FGFR3-activating mutation which results in impaired endochondral ossification. The effects of the mutation on membranous ossification are unknown. Fgfr3(Y367C/+) mice mimicking ACH and craniofacial analysis of patients with ACH and FGFR3-related craniosynostoses provide an opportunity to address this issue. Studying the calvaria and skull base, we observed abnormal cartilage and premature fusion of the synchondroses leading to modifications of foramen magnum shape and size in Fgfr3(Y367C/+) mice, ACH and FGFR3-related craniosynostoses patients. Partial premature fusion of the coronal sutures and non-ossified gaps in frontal bones were also present in Fgfr3(Y367C/+) mice and ACH patients. Our data provide strong support that not only endochondral ossification but also membranous ossification is severely affected in ACH. Demonstration of the impact of FGFR3 mutations on craniofacial development should initiate novel pharmacological and surgical therapeutic approaches.

  14. [Genetic mutation and clinical features of osteogenesis imperfecta type V].

    Science.gov (United States)

    Guan, Shizhen; Bai, Xue; Wang, Yi; Liu, Zhigang; Ren, Xiuzhi; Zhang, Tianke; Ju, Mingyan; Li, Keqiu; Li, Guang

    2017-12-10

    To explore genetic mutations and clinical features of osteogenesis imperfecta type V. Clinical record of five patients (including one familial case) with osteogenesis imperfecta type V were retrospectively analyzed. Peripheral blood samples of the patients, one family member, as well as healthy controls were collected. Mutation of IFITM5 gene was identified by PCR amplification and Sanger sequencing. A heterozygous mutation (c.-14C>T) in the 5-UTR of the IFITM5 gene was identified in all of the patients and one mother. The clinical findings included frequent fractures and spine and/or extremities deformities, absence of dentinogenesis imperfecta, absence of hearing impairment, and blue sclera in 1 case. Radiographic findings revealed calcification of the interosseous membrane between the radius-ulna in all cases. Hyperplastic callus formation was found in 3 cases. Four had radial-head dislocation. A single heterozygous mutation c.-14C>T was found in the 5-UTR of the IFITM5 gene in 5 patients with osteogensis imperfecta type V. The patients showed specific radiological features including calcification of interosseous membrane, hyperplastic callus formation, and radial-head dislocation.

  15. Germline CYBB mutations that selectively affect macrophages in kindreds with X-linked predisposition to tuberculous mycobacterial disease

    Science.gov (United States)

    Bustamante, Jacinta; Arias, Andres A; Vogt, Guillaume; Picard, Capucine; Galicia, Lizbeth Blancas; Prando, Carolina; Grant, Audrey V; Marchal, Christophe C; Hubeau, Marjorie; Chapgier, Ariane; de Beaucoudrey, Ludovic; Puel, Anne; Feinberg, Jacqueline; Valinetz, Ethan; Jannière, Lucile; Besse, Céline; Boland, Anne; Brisseau, Jean-Marie; Blanche, Stéphane; Lortholary, Olivier; Fieschi, Claire; Emile, Jean-François; Boisson-Dupuis, Stéphanie; Al-Muhsen, Saleh; Woda, Bruce; Newburger, Peter E; Condino-Neto, Antonio; Dinauer, Mary C; Abel, Laurent; Casanova, Jean-Laurent

    2011-01-01

    Germline mutations in CYBB, the human gene encoding the gp91phox subunit of the phagocyte NADPH oxidase, impair the respiratory burst of all types of phagocytes and result in X-linked chronic granulomatous disease (CGD). We report here two kindreds in which otherwise healthy male adults developed X-linked recessive Mendelian susceptibility to mycobacterial disease (MSMD) syndromes. These patients had previously unknown mutations in CYBB that resulted in an impaired respiratory burst in monocyte-derived macrophages but not in monocytes or granulocytes. The macrophage-specific functional consequences of the germline mutation resulted from cell-specific impairment in the assembly of the NADPH oxidase. This ‘experiment of nature’ indicates that CYBB is associated with MSMD and demonstrates that the respiratory burst in human macrophages is a crucial mechanism for protective immunity to tuberculous mycobacteria. PMID:21278736

  16. Hand eczema, atopic dermatitis and filaggrin mutations in adult Danes

    DEFF Research Database (Denmark)

    Heede, Nina G.; Thuesen, Betina H.; Thyssen, Jacob P.

    2017-01-01

    in the general population, especially among individuals with a history of atopic dermatitis. Moreover, self-reported hand eczema and atopic dermatitis were associated with particularly high risk of disability pension among FLG mutation carriers [odds ratio (OR) 4.02 and 95% confidence interval (CI): 1...... with a genetically impaired skin barrier, were associated with disability pension, suggesting that FLG mutations carriers with a history of atopic dermatitis and hand eczema could benefit from early attention with respect to choice of occupation....... a questionnaire about skin symptoms and hand eczema. Socioeconomic variables, including disability pension, and information on work in risk occupations were retrieved from national registries. The reasons for granting disability pension were unknown. Results: Disability pension was associated with hand eczema...

  17. Identification of a Novel Mutation in a Pseudohypoparathyroidism Family

    Directory of Open Access Journals (Sweden)

    Zhi-Min Miao

    2011-01-01

    Full Text Available Pseudohypoparathyroidism type Ia (PHP Ia is defined as a series of disorders characterized by multihormone resistance in end-organs and Albright hereditary osteodystrophy (AHO phenotype. PHP Ia is caused by heterozygous inactivating mutations in GNAS, which encodes the stimulatory G-protein alpha subunit (Gsa. A patient with typical clinical manifestations of pseudohypoparathyroidism (PHP (round face, short stature, centripetal obesity, brachydactyly, and multi-hormone resistance: parathyroid hormone (PTH, thyroid-stimulating hormone (TSH, and gonadotropins presented at our center. The sequence of the GNAS gene from the patient and her families revealed a novel missense mutation (Y318H in the proband and her mother. An in vitro Gsa functional study showed that Gsa function was significantly impaired. These results stress the importance of GNAS gene investigation.

  18. Inflammatory peeling skin syndrome caused a novel mutation in CDSN.

    Science.gov (United States)

    Telem, Dana Fuchs; Israeli, Shirli; Sarig, Ofer; Sprecher, Eli

    2012-04-01

    Generalized peeling skin syndrome (PSS) is a rare autosomal recessive dermatosis manifesting with continuous exfoliation of the stratum corneum. The inflammatory (type B) subtype of PSS was recently found to be caused by deleterious mutations in the CDSN gene encoding corneodesmosin, a major component of desmosomal junctions in the uppermost layers of the epidermis. In the present study, we assessed a 10-month-old baby, who presented with generalized superficial peeling of the skin. Using PCR amplification and direct sequencing, we identified the third PSS-associated mutation in CDSN, a homozygous 4 bp duplication in the second exon of the gene (c.164_167dup GCCT; p.Thr57ProfsX6). These data further support the notion that corneodesmosin deficiency impairs cell-cell adhesion in the upper epidermis, paving the way for an abnormal inflammatory response due to epidermal barrier disruption.

  19. 20 CFR 220.184 - If the annuitant becomes disabled by another impairment(s).

    Science.gov (United States)

    2010-04-01

    ... impairment(s). 220.184 Section 220.184 Employees' Benefits RAILROAD RETIREMENT BOARD REGULATIONS UNDER THE... Activity or Medical Improvement § 220.184 If the annuitant becomes disabled by another impairment(s). If a new severe impairment(s) begins in or before the month in which the last impairment(s) ends, the Board...

  20. Cognitive impairments in epilepsy

    Directory of Open Access Journals (Sweden)

    Aleksandr Anatolyevich Kostylev

    2013-01-01

    Full Text Available Cognitive impairments in epilepsy are a current problem in neurology. The basis of the idea on the pathogenesis of higher nervous system dysfunctions is the interaction of a few factors that include the form and duration of the disease, gender differences, and the impact of antiepileptic therapy. The role of interattack epileptiform changes in the development of cognitive deficit in adults and epileptic encephalopathies in children is discussed. Up-to-date neurophysiological and neuroimaging diagnostic methods allow the detection of new features in the course and progression of higher nervous system dysfunctions in epilepsy.

  1. Cognitive impairment and pragmatics.

    Science.gov (United States)

    Gutiérrez-Rexach, Javier; Schatz, Sara

    2016-01-01

    One of the most important ingredients of felicitous conversation exchanges is the adequate expression of illocutionary force and the achievement of perlocutionary effects, which can be considered essential to the functioning of pragmatic competence. The breakdown of illocutionary and perlocutionary functions is one of the most prominent external features of cognitive impairment in Alzheimer's Disease, with devastating psychological and social consequences for patients, their family and caregivers. The study of pragmatic functions is essential for a proper understanding of the linguistic and communicative aspects of Alzheimer's disease.

  2. Mutation breeding newsletter. No. 22

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  3. Mutation breeding newsletter. No. 34

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1989-07-01

    This issue of the Newsletter presents abstracts and short communications of research results on radiation and chemical induced mutation breeding projects. Positive traits such as disease resistance and increased productivity are highlighted.

  4. Mutation breeding newsletter. No. 29

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  5. Mutation breeding newsletter. No. 15

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  6. Mutation breeding newsletter. No. 5

    International Nuclear Information System (INIS)

    1975-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  7. Mutation breeding newsletter. No. 15

    International Nuclear Information System (INIS)

    1980-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  8. Mutation breeding newsletter. No. 14

    International Nuclear Information System (INIS)

    1979-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  9. Mutation breeding newsletter. No. 16

    International Nuclear Information System (INIS)

    1980-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  10. Mutation breeding newsletter. No. 12

    International Nuclear Information System (INIS)

    1978-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  11. Mutation breeding newsletter. No. 28

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-09-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  12. Mutation breeding newsletter. No. 29

    International Nuclear Information System (INIS)

    1987-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  13. Mutation breeding newsletter. No. 9

    International Nuclear Information System (INIS)

    1977-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  14. Mutation breeding newsletter. No. 7

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1976-01-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  15. Mutation Breeding Newsletter. No. 37

    International Nuclear Information System (INIS)

    1991-01-01

    This newsletter contains a brief account of FAO/IAEA meetings held in 1990 on plant breeding involving the use of induced mutations. It also features a list of commercially available plant cultivars produced by such techniques. Refs and tabs

  16. Mutation breeding newsletter. No. 4

    International Nuclear Information System (INIS)

    1974-08-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  17. Mutation breeding newsletter. No. 18

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  18. Mutation breeding newsletter. No. 9

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  19. Mutation breeding newsletter. No. 34

    International Nuclear Information System (INIS)

    1989-07-01

    This issue of the Newsletter presents abstracts and short communications of research results on radiation and chemical induced mutation breeding projects. Positive traits such as disease resistance and increased productivity are highlighted

  20. Mutation breeding newsletter. No. 24

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1984-07-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  1. Mutation breeding newsletter. No. 32

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  2. Mutation breeding newsletter. No. 36

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1990-07-01

    This issue of the Newsletter presents abstracts and short communications of research results on radiation and chemical induced mutation breeding projects. Positive traits such as disease resistance and increased productivity are highlighted.

  3. Mutation breeding newsletter. No. 3

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1974-01-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  4. Mutation breeding newsletter. No. 3

    International Nuclear Information System (INIS)

    1974-01-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  5. Mutation breeding newsletter. No. 11

    International Nuclear Information System (INIS)

    1978-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  6. Mutation breeding newsletter. No. 6

    International Nuclear Information System (INIS)

    1975-08-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  7. Mutation breeding newsletter. No. 1

    International Nuclear Information System (INIS)

    1972-05-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  8. Mutation breeding newsletter. No. 31

    International Nuclear Information System (INIS)

    1988-03-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  9. Mutation breeding newsletter. No. 44

    International Nuclear Information System (INIS)

    1999-04-01

    This issue of the Newsletter presents research reports on the role of radiation induced mutation and chemical mutagens in improving productivity, disease resistance; cold and salinity tolerance of various crops and ornamental plants

  10. Mutation breeding newsletter. No. 1

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1972-05-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  11. Mutation breeding newsletter. No. 25

    International Nuclear Information System (INIS)

    1985-01-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  12. Mutation breeding newsletter. No. 32

    International Nuclear Information System (INIS)

    1988-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  13. Mutation breeding newsletter. No. 5

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  14. Mutation breeding newsletter. No. 20

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  15. Mutation breeding newsletter. No. 28

    International Nuclear Information System (INIS)

    1986-09-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  16. Mutation breeding newsletter. No. 17

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1981-03-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  17. Mutation breeding newsletter. No. 16

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1980-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  18. Mutation breeding newsletter. No. 8

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1976-09-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  19. Mutation breeding newsletter. No. 4

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1974-08-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  20. Mutation breeding newsletter. No. 12

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1978-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  1. Mutation breeding newsletter. No. 6

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1975-08-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  2. Mutation breeding newsletter. No. 10

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1977-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  3. Mutation breeding newsletter. No. 14

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  4. Mutation breeding newsletter. No. 36

    International Nuclear Information System (INIS)

    1990-07-01

    This issue of the Newsletter presents abstracts and short communications of research results on radiation and chemical induced mutation breeding projects. Positive traits such as disease resistance and increased productivity are highlighted

  5. CHRNE Mutation and Congenital Myasthenia

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2009-01-01

    Full Text Available The CHRNE e1293insG mutation was identified in 14 (60% of 23 North African families with an early onset form of congenital myasthenic syndrome studied at centers in France, Tunisia, Algeria, and UK.

  6. Mutation breeding newsletter. No. 19

    International Nuclear Information System (INIS)

    1982-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  7. Mutation breeding newsletter. No. 7

    International Nuclear Information System (INIS)

    1976-01-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  8. Mutation breeding newsletter. No. 24

    International Nuclear Information System (INIS)

    1984-07-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  9. Mutation breeding newsletter. No. 20

    International Nuclear Information System (INIS)

    1982-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  10. Mutation breeding newsletter. No. 18

    International Nuclear Information System (INIS)

    1981-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  11. Mutation breeding newsletter. No. 31

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1988-03-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  12. Mutation breeding newsletter. No. 27

    International Nuclear Information System (INIS)

    1986-02-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  13. Mutation breeding newsletter. No. 26

    International Nuclear Information System (INIS)

    1985-10-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  14. Mutation breeding newsletter. No. 17

    International Nuclear Information System (INIS)

    1981-03-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  15. Mutation breeding newsletter. No. 30

    International Nuclear Information System (INIS)

    1987-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  16. Mutation breeding newsletter. No. 13

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1979-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  17. Mutation breeding newsletter. No. 30

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1987-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  18. Mutation breeding newsletter. No. 19

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1982-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  19. Mutation breeding newsletter. No. 26

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-10-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  20. Mutation breeding newsletter. No. 25

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1985-01-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  1. Mutation breeding newsletter. No. 23

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1983-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  2. Mutation breeding newsletter. No. 27

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1986-02-01

    This issue of the Newsletter presents reports and research abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  3. Mutation breeding newsletter. No. 2

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1973-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  4. Mutation breeding newsletter. No. 11

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1978-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants.

  5. Mutation breeding newsletter. No. 23

    International Nuclear Information System (INIS)

    1983-01-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  6. Mutation breeding newsletter. No. 2

    International Nuclear Information System (INIS)

    1973-02-01

    This issue of the Newsletter presents reports and rea search abstracts on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  7. Mutation breeding newsletter. No. 10

    International Nuclear Information System (INIS)

    1977-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  8. Mutation breeding newsletter. No. 8

    International Nuclear Information System (INIS)

    1976-09-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  9. Mutation breeding newsletter. No. 13

    International Nuclear Information System (INIS)

    1979-02-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  10. BRAF mutations in conjunctival melanoma

    DEFF Research Database (Denmark)

    Larsen, Ann-Cathrine; Dahl, Christina; Dahmcke, Christina M.

    2016-01-01

    with atypia. BRAF mutations were identified in 39 of 111 (35%) cases. The rate ratio of BRAF-mutated versus BRAF-wild-type melanoma did not change over time. BRAF mutations were associated with T1 stage (p = 0.007), young age (p = 0.001), male gender (p = 0.02), sun-exposed location (p = 0.01), mixed....../non-pigmented tumour colour (p = 0.02) and nevus origin (p = 0.005), but did not associate with prognosis. BRAF status in conjunctival melanoma and paired premalignant lesions corresponded in 19 of 20 cases. Immunohistochemistry detected BRAF V600E mutations with a sensitivity of 0.94 and a specificity of 1...

  11. Mutation breeding newsletter. No. 22

    International Nuclear Information System (INIS)

    1983-07-01

    This issue of the Newsletter presents new reports on mutation breeding programs using radiation or chemical mutagenesis to improve productivity, introduce disease resistance or induce morphological changes in crop plants

  12. Mutation breeding in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Neto, A T; Menten, J O.M. [Centro de Energia Nuclear na Agricultura, Piracicaba (Brazil); Ando, A

    1980-03-01

    How mutation induction is used for plant breeding in Brazil is reported. For upland rice, the combined treatment with gamma-ray and mutagens (ethylene imine or ethylmethane sulfonate) has been used on the variety, Dourado Precoce, and some mutants with shortculm length and/or earliness without altering the productivity have been obtained. A project on the quantitative and qualitative protein improvement in upland rice was also started in 1979. In corn, the effect of gamma-irradiation on heterosis has been analyzed, and it was found that the single hybrids from two parental lines derived from irradiated seeds had increased ear productivity. For beans (Phaseolus yulgaris), gamma-irradiation and chemical mutagens have been used to induce the mutants with different seed color, disease resistance to golden mosaic virus and Xanthomonas phaseoli, earliness, high productivity and high protein content. Some mutants with partly improved characters have been obtained in these experiments. Two varieties of wheat tolerant to aluminum toxicity have been obtained, but the one showed high lodging due to its unfavorable plant height, and the other was highly susceptible to culm rust. Therefore, irradiation experiments have been started to improve these characters. The projects involving the use of gamma-irradiation have been tested to obtain the mutant lines insensitive to photoperiod and resistant to bud-blight in soybean, the mutant lines resistant to mosaic virus in papaya, the photoperiod-insensitive mutants in sorghum, the mosaic virus resistant and non-flowering mutants in sugar cane, and the Fusarium and nematode-resistant mutants in black pepper.

  13. Fertility impairment in radiotherapy

    Directory of Open Access Journals (Sweden)

    Marta Biedka

    2016-02-01

    Full Text Available Infertility as a result of antineoplastic therapy is becoming a very important issue due to the growing incidence of neoplastic diseases. Routinely applied antineoplastic treatments and the illness itself lead to fertility disorders. Therapeutic methods used in antineoplastic treatment may cause fertility impairment or sterilization due to permanent damage to reproductive cells. The risk of sterilization depends on the patient’s sex, age during therapy, type of neoplasm, radiation dose and treatment area. It is known that chemotherapy and radiotherapy can lead to fertility impairment and the combination of these two gives an additive effect. The aim of this article is to raise the issue of infertility in these patients. It is of growing importance due to the increase in the number of children and young adults who underwent radiotherapy in the past. The progress in antineoplastic therapy improves treatment results, but at the same time requires a deeper look at existential needs of the patient. Reproductive function is an integral element of self-esteem and should be taken into account during therapy planning.

  14. KCNQ channels regulate age-related memory impairment.

    Directory of Open Access Journals (Sweden)

    Sonia Cavaliere

    Full Text Available In humans KCNQ2/3 heteromeric channels form an M-current that acts as a brake on neuronal excitability, with mutations causing a form of epilepsy. The M-current has been shown to be a key regulator of neuronal plasticity underlying associative memory and ethanol response in mammals. Previous work has shown that many of the molecules and plasticity mechanisms underlying changes in alcohol behaviour and addiction are shared with those of memory. We show that the single KCNQ channel in Drosophila (dKCNQ when mutated show decrements in associative short- and long-term memory, with KCNQ function in the mushroom body α/βneurons being required for short-term memory. Ethanol disrupts memory in wildtype flies, but not in a KCNQ null mutant background suggesting KCNQ maybe a direct target of ethanol, the blockade of which interferes with the plasticity machinery required for memory formation. We show that as in humans, Drosophila display age-related memory impairment with the KCNQ mutant memory defect mimicking the effect of age on memory. Expression of KCNQ normally decreases in aging brains and KCNQ overexpression in the mushroom body neurons of KCNQ mutants restores age-related memory impairment. Therefore KCNQ is a central plasticity molecule that regulates age dependent memory impairment.

  15. A novel dominant D109A CRYAB mutation in a family with myofibrillar myopathy affects αB-crystallin structure

    Directory of Open Access Journals (Sweden)

    Jakub P. Fichna

    2017-06-01

    Molecular modeling in accordance with muscle biopsy microscopic analyses predicted that D109A mutation influence both structure and function of CRYAB due to decreased stability of oligomers leading to aggregate formation. In consequence disrupted sarcomere cytoskeleton organization might lead to muscle pathology. We also suggest that mutated RQDE sequence of CRYAB could impair CRYAB chaperone-like activity and promote aggregation of lens crystallins.

  16. Germline but macrophage-tropic CYBB mutations in kindreds with X-linked predisposition to tuberculous mycobacterial diseases

    OpenAIRE

    2011-01-01

    Abstract Germline mutations in the human CYBB gene, encoding the gp91phox subunit of the phagocyte NADPH oxidase, impair the respiratory burst of phagocytes and result in X-linked chronic granulomatous disease. We report two kindreds in which otherwise healthy male adults show X-linked recessive Mendelian susceptibility to mycobacterial diseases. These patients harbor mutations in CYBB that profoundly reduce the respiratory burst in monocyte-derived macrophages, but not in monocyte...

  17. Patients with discordant responses to antiretroviral therapy have impaired killing of HIV-infected T cells.

    Directory of Open Access Journals (Sweden)

    Sekar Natesampillai

    2010-11-01

    Full Text Available In medicine, understanding the pathophysiologic basis of exceptional circumstances has led to an enhanced understanding of biology. We have studied the circumstance of HIV-infected patients in whom antiretroviral therapy results in immunologic benefit, despite virologic failure. In such patients, two protease mutations, I54V and V82A, occur more frequently. Expressing HIV protease containing these mutations resulted in less cell death, caspase activation, and nuclear fragmentation than wild type (WT HIV protease or HIV protease containing other mutations. The impaired induction of cell death was also associated with impaired cleavage of procaspase 8, a requisite event for HIV protease mediated cell death. Primary CD4 T cells expressing I54V or V82A protease underwent less cell death than with WT or other mutant proteases. Human T cells infected with HIV containing these mutations underwent less cell death and less Casp8p41 production than WT or HIV containing other protease mutations, despite similar degrees of viral replication. The reductions in cell death occurred both within infected cells, as well as in uninfected bystander cells. These data indicate that single point mutations within HIV protease which are selected in vivo can significantly impact the ability of HIV to kill CD4 T cells, while not impacting viral replication. Therefore, HIV protease regulates both HIV replication as well as HIV induced T cell depletion, the hallmark of HIV pathogenesis.

  18. Screening of three Mediterranean phenylketonuria mutations in ...

    Indian Academy of Sciences (India)

    as the most frequent mutation (Dahri et al. 2010). The. E280K mutation was also reported in Mediterranean popu- lations (Guldberg et al. 1993). Since Tunisia is a Mediter- ranean country, patients with PKU are presumed to have these mutations. The aim of this study was to assess prevalence of the three above mutations ...

  19. Signatures of mutational processes in human cancer

    NARCIS (Netherlands)

    Alexandrov, L.B.; Nik-Zainal, S.; Wedge, D.C.; Aparicio, S.A.; Behjati, S.; Biankin, A.V.; Bignell, G.R.; Bolli, N.; Borg, A.; Borresen-Dale, A.L.; Boyault, S.; Burkhardt, B.; Butler, A.P.; Caldas, C.; Davies, H.R.; Desmedt, C.; Eils, R.; Eyfjord, J.E.; Foekens, J.A.; Greaves, M.; Hosoda, F.; Hutter, B.; Ilicic, T.; Imbeaud, S.; Imielinsk, M.; Jager, N.; Jones, D.T.; Knappskog, S.; Kool, M.; Lakhani, S.R.; Lopez-Otin, C.; Martin, S.; Munshi, N.C.; Nakamura, H.; Northcott, P.A.; Pajic, M.; Papaemmanuil, E.; Paradiso, A.; Pearson, J.V.; Puente, X.S.; Raine, K.; Ramakrishna, M.; Richardson, A.L.; Richter, J.; Rosenstiel, P.; Schlesner, M.; Schumacher, T.N.; Span, P.N.; Teague, J.W.; Totoki, Y.; Tutt, A.N.; Valdes-Mas, R.; Buuren, M.M. van; Veer, L. van 't; Vincent-Salomon, A.; Waddell, N.; Yates, L.R.; Zucman-Rossi, J.; Futreal, P.A.; McDermott, U.; Lichter, P.; Meyerson, M.; Grimmond, S.M.; Siebert, R.; Campo, E.; Shibata, T.; Pfister, S.M.; Campbell, P.J.; Stratton, M.R.; Schlooz-Vries, M.S.; Tol, J.J. van; Laarhoven, H.W. van; Sweep, F.C.; Bult, P.; et al.,

    2013-01-01

    All cancers are caused by somatic mutations; however, understanding of the biological processes generating these mutations is limited. The catalogue of somatic mutations from a cancer genome bears the signatures of the mutational processes that have been operative. Here we analysed 4,938,362

  20. HRAS mutations in Costello syndrome: detection of constitutional activating mutations in codon 12 and 13 and loss of wild-type allele in malignancy.

    Science.gov (United States)

    Estep, Anne L; Tidyman, William E; Teitell, Michael A; Cotter, Philip D; Rauen, Katherine A

    2006-01-01

    Costello syndrome (CS) is a complex developmental disorder involving characteristic craniofacial features, failure to thrive, developmental delay, cardiac and skeletal anomalies, and a predisposition to develop neoplasia. Based on similarities with other cancer syndromes, we previously hypothesized that CS is likely due to activation of signal transduction through the Ras/MAPK pathway [Tartaglia et al., 2003]. In this study, the HRAS coding region was sequenced for mutations in a large, well-characterized cohort of 36 CS patients. Heterogeneous missense point mutations predicting an amino acid substitution were identified in 33/36 (92%) patients. The majority (91%) had a 34G --> A transition in codon 12. Less frequent mutations included 35G --> C (codon 12) and 37G --> T (codon 13). Parental samples did not have an HRAS mutation supporting the hypothesis of de novo heterogeneous mutations. There is phenotypic variability among patients with a 34G --> A transition. The most consistent features included characteristic facies and skin, failure to thrive, developmental delay, musculoskeletal abnormalities, visual impairment, cardiac abnormalities, and generalized hyperpigmentation. The two patients with 35G --> C had cardiac arrhythmias whereas one patient with a 37G --> T transversion had an enlarged aortic root. Of the patients with a clinical diagnosis of CS, neoplasia was the most consistent phenotypic feature for predicating an HRAS mutation. To gain an understanding of the relationship between constitutional HRAS mutations and malignancy, HRAS was sequenced in an advanced biphasic rhabdomyosarcoma/fibrosarcoma from an individual with a 34G --> A mutation. Loss of the wild-type HRAS allele was observed, suggesting tumorigenesis in CS patients is accompanied by additional somatic changes affecting HRAS. Finally, due to phenotypic overlap between CS and cardio-facio-cutaneous (CFC) syndromes, the HRAS coding region was sequenced in a well-characterized CFC cohort

  1. Glucocerebrosidase mutations and neuropsychiatric phenotypes in Parkinson's disease and Lewy body dementias: Review and meta-analyses.

    Science.gov (United States)

    Creese, Byron; Bell, Emily; Johar, Iskandar; Francis, Paul; Ballard, Clive; Aarsland, Dag

    2018-03-01

    Heterozygous mutations in glucocerebrosidase gene (GBA) are a major genetic risk factor for Parkinson's disease (PD) and dementia with Lewy bodies (DLB). Recently, there has been a considerable focus on the relationship between GBA mutations and emergence of cognitive impairment and neuropsychiatric symptoms in these diseases. Here, we review the literature in this area, with a particular focus, including meta-analysis, on the key neuropsychiatric symptoms of cognitive impairment, psychosis, and depression in Parkinson's disease. Our meta-analysis demonstrated that GBA mutations are associated with a 2.4-fold increased risk of cognitive impairment. In addition, our novel meta-analyses of psychosis and depression showed a 1.8- and 2.2-fold increased risk respectively associated with GBA mutations, although due to possible bias and heterogeneity the depression findings should be interpreted with caution. While the precise mechanisms which increase susceptibility to neurodegeneration in GBA carriers are not known, evidence of greater cortical Lewy body pathology, reduced patterns of cortical activation, and hippocampal pathology in animal models are all consistent with a direct effect of GBA mutations on these symptoms. Extension of this work in DLB and individuals without neurodegeneration will be important in further characterizing how GBA mutations increase risk for PD and DLB and influence disease course. © 2017 Wiley Periodicals, Inc.

  2. Mitochondrial 12S rRNA A827G mutation is involved in the genetic susceptibility to aminoglycoside ototoxicity

    International Nuclear Information System (INIS)

    Xing Guangqian; Chen Zhibin; Wei Qinjun; Tian Huiqin; Li Xiaolu; Zhou Aidong; Bu Xingkuan; Cao Xin

    2006-01-01

    We have analyzed the clinical and molecular characterization of a Chinese family with aminoglycoside-induced and non-syndromic hearing impairment. Clinical evaluations revealed that only those family members who had a history of exposure to aminoglycoside antibiotics subsequently developed hearing loss, suggesting mitochondrial genome involvement. Sequence analysis of the mitochondrial 12S rRNA and tRNA Ser(UCN) genes led to the identification of a homoplasmic A827G mutation in all maternal relatives, a mutation that was identified previously in a few sporadic patients and in another Chinese family with non-syndromic deafness. The pathogenicity of the A827G mutation is strongly supported by the occurrence of the same mutation in two independent families and several genetically unrelated subjects. The A827G mutation is located at the A-site of the mitochondrial 12S rRNA gene which is highly conserved in mammals. It is possible that the alteration of the tertiary or quaternary structure of this rRNA by the A827G mutation may lead to mitochondrial dysfunction, thereby playing a role in the pathogenesis of hearing loss and aminoglycoside hypersensitivity. However, incomplete penetrance of hearing impairment indicates that the A827G mutation itself is not sufficient to produce clinical phenotype but requires the involvement of modifier factors for the phenotypic expression. Indeed, aminoglycosides may contribute to the phenotypic manifestation of the A827G mutation in this family. In contrast with the congenital or early-onset hearing impairment in another Chinese family carrying the A827G mutation, three patients in this pedigree developed hearing loss only after use of aminoglycosides. This discrepancy likely reflects the difference of genetic backgrounds, either mitochondrial haplotypes or nuclear modifier genes, between two families

  3. Post-stroke cognitive impairments

    Directory of Open Access Journals (Sweden)

    Elena Anatolyevna Katunina

    2013-01-01

    Full Text Available Post-stroke cognitive impairments are common effects of stroke. Vascular cognitive impairments are characterized by the heterogeneity of the neuropsychological profile in relation to the site and pattern of stroke. Their common trait is the presence of dysregulation secondary to frontal dysfunction. The treatment of vascular cognitive impairments should be multimodality and aimed at stimulating neuroplasticity processes, restoring neurotransmitter imbalance, and preventing recurrent vascular episodes.

  4. Impairments in Skin Integrity.

    Science.gov (United States)

    Murphree, Rose W

    2017-09-01

    Altered skin integrity increases the chance of infection, impaired mobility, and decreased function and may result in the loss of limb or, sometimes, life. Skin is affected by both intrinsic and extrinsic factors. Intrinsic factors can include altered nutritional status, vascular disease issues, and diabetes. Extrinsic factors include falls, accidents, pressure, immobility, and surgical procedures. Ensuring skin integrity in the elderly requires a team approach and includes the individual, caregivers, and clinicians. The twenty-first century clinician has several online, evidence-based tools to assist with optimal treatment plans. Understanding best practices in addressing skin integrity issues can promote positive outcomes with the elderly. Copyright © 2017 Elsevier Inc. All rights reserved.

  5. Computational analysis of histidine mutations on the structural stability of human tyrosinases leading to albinism insurgence.

    Science.gov (United States)

    Hassan, Mubashir; Abbas, Qamar; Raza, Hussain; Moustafa, Ahmed A; Seo, Sung-Yum

    2017-07-25

    Misfolding and structural alteration in proteins lead to serious malfunctions and cause various diseases in humans. Mutations at the active binding site in tyrosinase impair structural stability and cause lethal albinism by abolishing copper binding. To evaluate the histidine mutational effect, all mutated structures were built using homology modelling. The protein sequence was retrieved from the UniProt database, and 3D models of original and mutated human tyrosinase sequences were predicted by changing the residual positions within the target sequence separately. Structural and mutational analyses were performed to interpret the significance of mutated residues (N 180 , R 202 , Q 202 , R 211 , Y 363 , R 367 , Y 367 and D 390 ) at the active binding site of tyrosinases. CSpritz analysis depicted that 23.25% residues actively participate in the instability of tyrosinase. The accuracy of predicted models was confirmed through online servers ProSA-web, ERRAT score and VERIFY 3D values. The theoretical pI and GRAVY generated results also showed the accuracy of the predicted models. The CCA negative correlation results depicted that the replacement of mutated residues at His within the active binding site disturbs the structural stability of tyrosinases. The predicted CCA scores of Tyr 367 (-0.079) and Q/R 202 (0.032) revealed that both mutations have more potential to disturb the structural stability. MD simulation analyses of all predicted models justified that Gln 202 , Arg 202 , Tyr 367 and D 390 replacement made the protein structures more susceptible to destabilization. Mutational results showed that the replacement of His with Q/R 202 and Y/R 363 has a lethal effect and may cause melanin associated diseases such as OCA1. Taken together, our computational analysis depicts that the mutated residues such as Q/R 202 and Y/R 363 actively participate in instability and misfolding of tyrosinases, which may govern OCA1 through disturbing the melanin biosynthetic pathway.

  6. Mutation screening of the PCDH15 gene in Spanish patients with Usher syndrome type I.

    Science.gov (United States)

    Jaijo, Teresa; Oshima, Aki; Aller, Elena; Carney, Carol; Usami, Shin-ichi; Millán, José M; Kimberling, William J

    2012-01-01

    PCDH15 codes for protocadherin-15, a cell-cell adhesion protein essential in the morphogenesis and cohesion of stereocilia bundles and in the function or preservation of photoreceptor cells. Mutations in the PCDH15 gene are responsible for Usher syndrome type I (USH1F) and non-syndromic hearing loss (DFNB23). The purpose of this work was to perform PCDH15 mutation screening to identify the genetic cause of the disease in a cohort of Spanish patients with Usher syndrome type I and establish phenotype-genotype correlation. Mutation analysis of PCDH15 included additional exons recently identified and was performed by direct sequencing. The screening was performed in 19 probands with USH already screened for mutations in the most prevalent USH1 genes, myosin VIIA (MYO7A) and cadherin-23 (CDH23), and for copy number variants in PCDH15. Seven different point mutations, five novel, were detected. Including the large PCDH15 rearrangements previously reported in our cohort of patients, a total of seven of 19 patients (36.8%) were carriers of at least one pathogenic allele. Thirteen out of the 38 screened alleles carried pathogenic PCDH15 variants (34.2%). Five out of the seven point mutations reported in the present study are novel, supporting the idea that most PCDH15 mutations are private. Furthermore, no mutational hotspots have been identified. In most patients, detected mutations led to a truncated protein, reinforcing the hypothesis that severe mutations cause the Usher I phenotype and that missense variants are mainly responsible for non-syndromic hearing impairment.

  7. CDKL5 and ARX mutations are not responsible for early onset severe myoclonic epilepsy in infancy.

    Science.gov (United States)

    Nabbout, Rima; Depienne, Christel; Chipaux, Mathilde; Girard, Benoit; Souville, Isabelle; Trouillard, Oriane; Dulac, Olivier; Chelly, Jamel; Afenjar, Alexandra; Héron, Delphine; Leguern, Eric; Beldjord, Cherif; Bienvenu, Thierry; Bahi-Buisson, Nadia

    2009-11-01

    Severe myoclonic epilepsy of infancy (SMEI) or Dravet syndrome (DS) is a distinctive epilepsy syndrome often associated with de novo mutations in the SCN1A gene. However, 25-30% patients with SMEI/DS are negative for SCN1A mutation screening, suggesting that other molecular mechanisms may account for these disorders. Given the overlapping and heterogeneous clinical features of CDKL5- and ARX-related epilepsies and SMEI/DS, we postulated that CDKL5 mutations in females and ARX mutations gene in males may be associated with early onset seizures forms of SMEI/DS. Twenty-eight patients with early onset SMEI/DS before 6 months negative for SCN1A mutational screening were selected and screened for mutations in the ARX gene in males (n=14) or the CDKL5 gene in females (n=14). No mutations in either gene were found except one intronic variation of uncertain pathogenicity in the CDKL5 gene. All patients started seizures at mean age of 3.48 months. Thirteen patients had familial history of epilepsy or febrile seizures. Patients evolved toward refractory epilepsy with generalized tonic clonic seizures (18/28) and myoclonia (23/28) and severe neurological impairment with autistic features (13/28), ataxia (14/28) and spasticity (5/28). No patient ever exhibited infantile spasms, dystonia, or Rett-like features. Our results illustrate that mutation screening of ARX and CDKL5 is not effective in patients selected on the basis of clinical signs associated to early onset SMEI/DS. In addition, they might reflect that other phenotypic features associated with CDKL5 mutations (Rett-like features, infantile spasm) or ARX mutations (dystonia, spasticity) are more distinctive. 2009 Elsevier B.V. All rights reserved.

  8. Expanding the spectrum of HEXA mutations in Indian patients with Tay–Sachs disease

    Directory of Open Access Journals (Sweden)

    Jayesh Sheth

    2014-01-01

    Full Text Available Tay–Sachs disease is an autosomal recessive neurodegenerative disorder occurring due to impaired activity of β-hexosaminidase-A (EC 3.2.1.52, resulting from the mutation in HEXA gene. Very little is known about the molecular pathology of TSD in Indian children except for a few mutations identified by us. The present study is aimed to determine additional mutations leading to Tay–Sachs disease in nine patients confirmed by the deficiency of β-hexosaminidase-A (C (D175A and c.805G>C (p.G269R in one case; and one small 1 bp deletion c.426delT (p.F142LfsX57 and one splice site mutation c.459+4A>C in the other two cases respectively. None of these mutations were detected in 100 chromosomes from healthy individuals of the same ethnic group. Three previously reported missense mutations, (i c.532C>T (p.R178C, (ii c.964G>T (p.D322Y, and (iii c.1385A>T (p.E462V; two nonsense mutations (i c.709C>T (p.Q237X and (ii c.1528C>T (p.R510X, one 4 bp insertion c.1277_1278insTATC (p.Y427IfsX5 and one splice site mutation c.459+5G>A were also identified in six cases. We observe from this study that novel mutations are more frequently observed in Indian patients with Tay–Sachs disease with clustering of ~73% of disease causing mutations in exons 5 to 12. This database can be used for a carrier rate screening in the larger population of the country.

  9. Expanding the spectrum of HEXA mutations in Indian patients with Tay-Sachs disease.

    Science.gov (United States)

    Sheth, Jayesh; Mistri, Mehul; Datar, Chaitanya; Kalane, Umesh; Patil, Shekhar; Kamate, Mahesh; Shah, Harshuti; Nampoothiri, Sheela; Gupta, Sarita; Sheth, Frenny

    2014-01-01

    Tay-Sachs disease is an autosomal recessive neurodegenerative disorder occurring due to impaired activity of β-hexosaminidase-A (EC 3.2.1.52), resulting from the mutation in HEXA gene. Very little is known about the molecular pathology of TSD in Indian children except for a few mutations identified by us. The present study is aimed to determine additional mutations leading to Tay-Sachs disease in nine patients confirmed by the deficiency of β-hexosaminidase-A (C (D175A) and c.805G>C (p.G269R) in one case; and one small 1 bp deletion c.426delT (p.F142LfsX57) and one splice site mutation c.459+4A>C in the other two cases respectively. None of these mutations were detected in 100 chromosomes from healthy individuals of the same ethnic group. Three previously reported missense mutations, (i) c.532C>T (p.R178C), (ii) c.964G>T (p.D322Y), and (iii) c.1385A>T (p.E462V); two nonsense mutations (i) c.709C>T (p.Q237X) and (ii) c.1528C>T (p.R510X), one 4 bp insertion c.1277_1278insTATC (p.Y427IfsX5) and one splice site mutation c.459+5G>A were also identified in six cases. We observe from this study that novel mutations are more frequently observed in Indian patients with Tay-Sachs disease with clustering of ~ 73% of disease causing mutations in exons 5 to 12. This database can be used for a carrier rate screening in the larger population of the country.

  10. [Multilingualism and specific language impairment].

    Science.gov (United States)

    Arkkila, Eva; Smolander, Sini; Laasonen, Marja

    2013-01-01

    Specific language impairment is one of the most common developmental disturbances in childhood. With the increase of the foreign language population group an increasing number of children assimilating several languages and causing concern in language development attend clinical examinations. Knowledge of factors underlying the specific language impairment and the specific impairment in general, special features of language development of those learning several languages, as well as the assessment and support of the linguistic skills of a multilingual child is essential. The risk of long-term problems and marginalization is high for children having specific language impairment.

  11. Engineered mutations in fibrillin-1 leading to Marfan syndrome act at the protein, cellular and organismal levels.

    Science.gov (United States)

    Zeyer, Karina A; Reinhardt, Dieter P

    2015-01-01

    Fibrillins are the major components of microfibrils in the extracellular matrix of elastic and non-elastic tissues. They are multi-domain proteins, containing primarily calcium binding epidermal growth factor-like (cbEGF) domains and 8-cysteine/transforming growth factor-beta binding protein-like (TB) domains. Mutations in the fibrillin-1 gene give rise to Marfan syndrome, a connective tissue disorder with clinical complications in the cardiovascular, skeletal, ocular and other organ systems. Here, we review the consequences of engineered Marfan syndrome mutations in fibrillin-1 at the protein, cellular and organismal levels. Representative point mutations associated with Marfan syndrome in affected individuals have been introduced and analyzed in recombinant fibrillin-1 fragments. Those mutations affect fibrillin-1 on a structural and functional level. Mutations which impair folding of cbEGF domains can affect protein trafficking. Protein folding disrupted by some mutations can lead to defective secretion in mutant fibrillin-1 fragments, whereas fragments with other Marfan mutations are secreted normally. Many Marfan mutations render fibrillin-1 more susceptible to proteolysis. There is also evidence that some mutations affect heparin binding. Few mutations have been further analyzed in mouse models. An extensively studied mouse model of Marfan syndrome expresses mouse fibrillin-1 with a missense mutation (p.C1039G). The mice display similar characteristics to human patients with Marfan syndrome. Overall, the analyses of engineered mutations leading to Marfan syndrome provide important insights into the pathogenic molecular mechanisms exerted by mutated fibrillin-1. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. Mechanistic study on the nuclear modifier gene MSS1 mutation suppressing neomycin sensitivity of the mitochondrial 15S rRNA C1477G mutation in Saccharomyces cerevisiae.

    Science.gov (United States)

    Zhou, Qiyin; Wang, Wei; He, Xiangyu; Zhu, Xiaoyu; Shen, Yaoyao; Yu, Zhe; Wang, Xuexiang; Qi, Xuchen; Zhang, Xuan; Fan, Mingjie; Dai, Yu; Yang, Shuxu; Yan, Qingfeng

    2014-01-01

    The phenotypic manifestation of mitochondrial DNA (mtDNA) mutations can be modulated by nuclear genes and environmental factors. However, neither the interaction among these factors nor their underlying mechanisms are well understood. The yeast Saccharomyces cerevisiae mtDNA 15S rRNA C1477G mutation (PR) corresponds to the human 12S rRNA A1555G mutation. Here we report that a nuclear modifier gene mss1 mutation suppresses the neomycin-sensitivity phenotype of a yeast C1477G mutant in fermentable YPD medium. Functional assays show that the mitochondrial function of the yeast C1477G mutant was impaired severely in YPD medium with neomycin. Moreover, the mss1 mutation led to a significant increase in the steady-state level of HAP5 (heme activated protein), which greatly up-regulated the expression of glycolytic transcription factors RAP1, GCR1, and GCR2 and thus stimulated glycolysis. Furthermore, the high expression of the key glycolytic enzyme genes HXK2, PFK1 and PYK1 indicated that enhanced glycolysis not only compensated for the ATP reduction from oxidative phosphorylation (OXPHOS) in mitochondria, but also ensured the growth of the mss1(PR) mutant in YPD medium with neomycin. This study advances our understanding of the phenotypic manifestation of mtDNA mutations.

  13. Mutations in the NHEJ component XRCC4 cause primordial dwarfism.

    Science.gov (United States)

    Murray, Jennie E; van der Burg, Mirjam; IJspeert, Hanna; Carroll, Paula; Wu, Qian; Ochi, Takashi; Leitch, Andrea; Miller, Edward S; Kysela, Boris; Jawad, Alireza; Bottani, Armand; Brancati, Francesco; Cappa, Marco; Cormier-Daire, Valerie; Deshpande, Charu; Faqeih, Eissa A; Graham, Gail E; Ranza, Emmanuelle; Blundell, Tom L; Jackson, Andrew P; Stewart, Grant S; Bicknell, Louise S

    2015-03-05

    Non-homologous end joining (NHEJ) is a key cellular process ensuring genome integrity. Mutations in several components of the NHEJ pathway have been identified, often associated with severe combined immunodeficiency (SCID), consistent with the requirement for NHEJ during V(D)J recombination to ensure diversity of the adaptive immune system. In contrast, we have recently found that biallelic mutations in LIG4 are a common cause of microcephalic primordial dwarfism (MPD), a phenotype characterized by prenatal-onset extreme global growth failure. Here we provide definitive molecular genetic evidence supported by biochemical, cellular, and immunological data for mutations in XRCC4, encoding the obligate binding partner of LIG4, causing MPD. We report the identification of biallelic mutations in XRCC4 in five families. Biochemical and cellular studies demonstrate that these alterations substantially decrease XRCC4 protein levels leading to reduced cellular ligase IV activity. Consequently, NHEJ-dependent repair of ionizing-radiation-induced DNA double-strand breaks is compromised in XRCC4 cells. Similarly, immunoglobulin junctional diversification is impaired in cells. However, immunoglobulin levels are normal, and individuals lack overt signs of immunodeficiency. Additionally, in contrast to individuals with LIG4 mutations, pancytopenia leading to bone marrow failure has not been observed. Hence, alterations that alter different NHEJ proteins give rise to a phenotypic spectrum, from SCID to extreme growth failure, with deficiencies in certain key components of this repair pathway predominantly exhibiting growth deficits, reflecting differential developmental requirements for NHEJ proteins to support growth and immune maturation. Copyright © 2015 The American Society of Human Genetics. Published by Elsevier Inc. All rights reserved.

  14. Next-generation sequencing reveals the mutational landscape of clinically diagnosed Usher syndrome: copy number variations, phenocopies, a predominant target for translational read-through, and PEX26 mutated in Heimler syndrome.

    Science.gov (United States)

    Neuhaus, Christine; Eisenberger, Tobias; Decker, Christian; Nagl, Sandra; Blank, Cornelia; Pfister, Markus; Kennerknecht, Ingo; Müller-Hofstede, Cornelie; Charbel Issa, Peter; Heller, Raoul; Beck, Bodo; Rüther, Klaus; Mitter, Diana; Rohrschneider, Klaus; Steinhauer, Ute; Korbmacher, Heike M; Huhle, Dagmar; Elsayed, Solaf M; Taha, Hesham M; Baig, Shahid M; Stöhr, Heidi; Preising, Markus; Markus, Susanne; Moeller, Fabian; Lorenz, Birgit; Nagel-Wolfrum, Kerstin; Khan, Arif O; Bolz, Hanno J

    2017-09-01

    Combined retinal degeneration and sensorineural hearing impairment is mostly due to autosomal recessive Usher syndrome (USH1: congenital deafness, early retinitis pigmentosa (RP); USH2: progressive hearing impairment, RP). Sanger sequencing and NGS of 112 genes (Usher syndrome, nonsyndromic deafness, overlapping conditions), MLPA, and array-CGH were conducted in 138 patients clinically diagnosed with Usher syndrome. A molecular diagnosis was achieved in 97% of both USH1 and USH2 patients, with biallelic mutations in 97% (USH1) and 90% (USH2), respectively. Quantitative readout reliably detected CNVs (confirmed by MLPA or array-CGH), qualifying targeted NGS as one tool for detecting point mutations and CNVs. CNVs accounted for 10% of identified USH2A alleles, often in trans to seemingly monoallelic point mutations. We demonstrate PTC124-induced read-through of the common p.Trp3955* nonsense mutation (13% of detected USH2A alleles), a potential therapy target. Usher gene mutations were found in most patients with atypical Usher syndrome, but the diagnosis was adjusted in case of double homozygosity for mutations in OTOA and NR2E3 , genes implicated in isolated deafness and RP. Two patients with additional enamel dysplasia had biallelic PEX26 mutations, for the first time linking this gene to Heimler syndrome. Targeted NGS not restricted to Usher genes proved beneficial in uncovering conditions mimicking Usher syndrome.

  15. Age-related increase in the rate of spontaneou and γ-ray-induced hprt mutations in mouse spleen lymphocytes

    International Nuclear Information System (INIS)

    Gazlev, A.I.; Podlutskii, A.Ya.; Bradbury, R.

    1994-01-01

    Endogenous and exogenous factors continually afflict DNA of cells of organisms. A certain amount of the damage is accumulated causing mutations, increasing the risk of malignacies, impairing cell functions, and upsetting the body's homeostasis. The research reported here studies the rates of spontaneous hprt nmutationsand those induced you ggammairradiation in the splenocytes of mice at various ages. The rate of spontaneous and induced hprt gene mutations increases with aging. In gamma irradiated mice the rate of radiation-induced mutations depended on the absorbed dose and age, with the rate 2.3-3.0 fold higher in 104-110 week old mice than in younger pups. 15 refs., 1 tab

  16. Common Β- Thalassaemia Mutations in

    Directory of Open Access Journals (Sweden)

    P Azarfam

    2005-01-01

    Full Text Available Introduction: β –Thalassaemia was first explained by Thomas Cooly as Cooly’s anaemia in 1925. The β- thalassaemias are hereditary autosomal disorders with decreased or absent β-globin chain synthesis. The most common genetic defects in β-thalassaemias are caused by point mutations, micro deletions or insertions within the β-globin gene. Material and Methods: In this research , 142 blood samples (64 from childrens hospital of Tabriz , 15 samples from Shahid Gazi hospital of Tabriz , 18 from Urumia and 45 samples from Aliasghar hospital of Ardebil were taken from thalassaemic patients (who were previously diagnosed .Then 117 non-familial samples were selected . The DNA of the lymphocytes of blood samples was extracted by boiling and Proteinase K- SDS procedure, and mutations were detected by ARMS-PCR methods. Results: From the results obtained, eleven most common mutations,most of which were Mediterranean mutations were detected as follows; IVS-I-110(G-A, IVS-I-1(G-A ،IVS-I-5(G-C ,Frameshift Codon 44 (-C,( codon5(-CT,IVS-1-6(T-C, IVS-I-25(-25bp del ,Frameshift 8.9 (+G ,IVS-II-1(G-A ,Codon 39(C-T, Codon 30(G-C the mutations of the samples were defined. The results showed that Frameshift 8.9 (+G, IVS-I-110 (G-A ,IVS-II-I(G-A, IVS-I-5(G-C, IVS-I-1(G-A , Frameshift Codon 44(-C , codon5(-CT , IVS-1-6(T-C , IVS-I-25(-25bp del with a frequency of 29.9%, 25.47%,17.83%, 7.00%, 6.36% , 6.63% , 3.8% , 2.5% , 0.63% represented the most common mutations in North - west Iran. No mutations in Codon 39(C-T and Codon 30(G-C were detected. Cunclusion: The frequency of the same mutations in patients from North - West of Iran seems to be different as compared to other regions like Turkey, Pakistan, Lebanon and Fars province of Iran. The pattern of mutations in this region is more or less the same as in the Mediterranean region, but different from South west Asia and East Asia.

  17. SQSTM1 Mutations and Glaucoma.

    Directory of Open Access Journals (Sweden)

    Todd E Scheetz

    Full Text Available Glaucoma is the most common cause of irreversible blindness worldwide. One subset of glaucoma, normal tension glaucoma (NTG occurs in the absence of high intraocular pressure. Mutations in two genes, optineurin (OPTN and TANK binding kinase 1 (TBK1, cause familial NTG and have known roles in the catabolic cellular process autophagy. TKB1 encodes a kinase that phosphorylates OPTN, an autophagy receptor, which ultimately activates autophagy. The sequestosome (SQSTM1 gene also encodes an autophagy receptor and also is a target of TBK1 phosphorylation. Consequently, we hypothesized that mutations in SQSTM1 may also cause NTG. We tested this hypothesis by searching for glaucoma-causing mutations in a cohort of NTG patients (n = 308 and matched controls (n = 157 using Sanger sequencing. An additional 1098 population control samples were also analyzed using whole exome sequencing. A total of 17 non-synonymous mutations were detected which were not significantly skewed between cases and controls when analyzed separately, or as a group (p > 0.05. These data suggest that SQSTM1 mutations are not a common cause of NTG.

  18. Mutation breeding in Philippine fruits

    International Nuclear Information System (INIS)

    Espino, R.R.C.

    1987-09-01

    Studies were made to establish standard conditions for mutation induction by gamma-irradiation to be performed in combination with in-vitro culture for banana and citrus spp. Besides this, radio-sensitivity of seeds and/or plantlets of mango, sugar apple, soursop, lanzones and Jack fruit was investigated and primary observation on the occurrence of mutation was made. For the mutagenesis of banana shoot tip cultures, radio-sensitivity of plantlets derived from the culture as well as fresh-cultured shoots was examined and phenotypes indicative of mutation, such as chlorophyl streaking, slow growth, pigmentation and varied bunch orientation were recorded. Isozyme analysis for mutated protein structure was not conclusive. In the in-vitro culture of Citrus spp., seeds placed on fresh media as well as germinating seeds and two-leaf stage seedlings in test tubes were examined for their radio-sensitivity. Irradiated materials were propagated for further observation. In these two crops, basic methodology for mutation induction with combined use of in-vitro culture and gamma-irradiation was established. In mango, sugar apple, soursop, lanzones and Jack fruit, basic data on radiosensitivity were obtained. In mango, leaf abnormalities were observed after the treatment of scions

  19. 20 CFR 416.998 - If you become disabled by another impairment(s).

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false If you become disabled by another impairment... Disability Or Blindness § 416.998 If you become disabled by another impairment(s). If a new severe impairment(s) begins in or before the month in which your last impairment(s) ends, we will find that your...

  20. 20 CFR 404.1598 - If you become disabled by another impairment(s).

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false If you become disabled by another impairment... Disability § 404.1598 If you become disabled by another impairment(s). If a new severe impairment(s) begins in or before the month in which your last impairment(s) ends, we will find that your disability is...

  1. Cognitive impairment, clinical severity and MRI changes in MELAS syndrome.

    Science.gov (United States)

    Kraya, Torsten; Neumann, Lena; Paelecke-Habermann, Yvonne; Deschauer, Marcus; Stoevesandt, Dietrich; Zierz, Stephan; Watzke, Stefan

    2017-12-29

    To examine clinical severity, cognitive impairment, and MRI changes in patients with MELAS syndrome. Cognitive-mnestic functions, brain MRI (lesion load, cella media index) and clinical severity of ten patients with MELAS syndrome were examined. All patients carried the m.3243A>G mutation. The detailed neuropsychological assessment revealed cognitive deficits in attention, executive function, visuoperception, and -construction. There were significant correlations between these cognitive changes, lesion load in MRI, disturbances in everyday life (clinical scale), and high scores in NMDAS. Patients with MELAS syndrome showed no global neuropsychological deficit, but rather distinct cognitive deficits. Copyright © 2018 Elsevier B.V. and Mitochondria Research Society. All rights reserved.

  2. Compound heterozygous MYO7A mutations segregating Usher syndrome type 2 in a Han family.

    Science.gov (United States)

    Zong, Ling; Chen, Kaitian; Wu, Xuan; Liu, Min; Jiang, Hongyan

    2016-11-01

    Identification of rare deafness genes for inherited congenital sensorineural hearing impairment remains difficult, because a large variety of genes are implicated. In this study we applied targeted capture and next-generation sequencing to uncover the underlying gene in a three-generation Han family segregating recessive inherited hearing loss and retinitis pigmentosa. After excluding mutations in common deafness genes GJB2, SLC26A4 and the mitochondrial gene, genomic DNA of the proband of a Han family was subjected to targeted next-generation sequencing. The candidate mutations were confirmed by Sanger sequencing and subsequently analyzed with in silico tools. An unreported splice site mutation c.3924+1G > C compound with c.6028G > A in the MYO7A gene were detected to cosegregate with the phenotype in this pedigree. Both mutations, located in the evolutionarily conserved FERM domain in myosin VIIA, were predicted to be pathogenic. In this family, profound sensorineural hearing impairment and retinitis pigmentosa without vestibular disorder, constituted the typical Usher syndrome type 2. Identification of novel mutation in compound heterozygosity in MYO7A gene revealed the genetic origin of Usher syndrome type 2 in this Han family. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  3. SIL1 mutations and clinical spectrum in patients with Marinesco-Sjogren syndrome.

    Science.gov (United States)

    Krieger, Michael; Roos, Andreas; Stendel, Claudia; Claeys, Kristl G; Sonmez, Fatma Mujgan; Baudis, Michael; Bauer, Peter; Bornemann, Antje; de Goede, Christian; Dufke, Andreas; Finkel, Richard S; Goebel, Hans H; Häussler, Martin; Kingston, Helen; Kirschner, Janbernd; Medne, Livija; Muschke, Petra; Rivier, François; Rudnik-Schöneborn, Sabine; Spengler, Sabrina; Inzana, Francesca; Stanzial, Franco; Benedicenti, Francesco; Synofzik, Matthis; Lia Taratuto, Ana; Pirra, Laura; Tay, Stacey Kiat-Hong; Topaloglu, Haluk; Uyanik, Gökhan; Wand, Dorothea; Williams, Denise; Zerres, Klaus; Weis, Joachim; Senderek, Jan

    2013-12-01

    missing in young children. As cognitive impairment is not obligatory, patients without intellectual disability but a Marinesco-Sjögren syndrome-compatible phenotype should receive SIL1 mutation analysis. Despite allelic heterogeneity and many families with private mutations, the phenotype related to SIL1 mutations is relatively homogenous. Based on SIL1 expression studies we speculate that this may arise from a uniform effect of different mutations on protein expression.

  4. Mutation in cultured mammalian cells

    International Nuclear Information System (INIS)

    Nakamura, N.; Okada, S.

    1982-01-01

    Mammalian cell cultures were exposed to gamma-rays at various dose rates. Dose-rate effects were observed in cultured somatic cells of the mouse for cell killing and mutations resistant to 6-thioguanine (TGsup(r)) and to methotrexate (MTXsup(r)). Linear quadratic model may be applied to cell killing and TGsup(r) mutations in some cases but can not explain the whole data. Results at low doses with far low dose-rate were not predictable from data at high doses with acute or chronic irradiation. Radioprotective effects of dimethyl sulfoxide were seen only after acute exposure but not after chronic one, suggesting that damages by indirect action of radiations may be potentially reparable by cells. TGsup(r) mutations seem to contain gross structural changes whereas MTXsup(r) ones may have smaller alterations. (Namekawa, K.)

  5. Thalassemia mutations in Gaziantep, Turkey

    African Journals Online (AJOL)

    STORAGESEVER

    2010-02-22

    Feb 22, 2010 ... Table 3. Frequency of β-thalassemia mutations in the Eastern Mediterranean. Mutation. This study Turkey Cyprus Greece Syria Palestine Bulgaria Azerbaijan Iran Iraq. IVS 1.110 (G>A). 29.1. 39.3. 79.7. 42.1. 24.1. 17.6. 24.2. 20.2. 4.8 1.9. IVS 2.1 (G>A). 12.3. 4.7. -. 3.3. 4.2. 2.9. -. -. 33.9 18.3. IVS 1.1 (G>A).

  6. Cognitive Impairment Associated with Cancer

    Science.gov (United States)

    Pendergrass, J. Cara; Harrison, John E.

    2018-01-01

    This brief review explores the areas of cognitive impairment that have been observed in cancer patients and survivors, the cognitive assessment tools used, and the management of the observed cognitive changes. Cognitive changes and impairment observed in patients with cancer and those in remission can be related to the direct effects of cancer itself, nonspecific factors or comorbid conditions that are independent of the actual disease, and/or the treatments or combination of treatments administered. Attention, memory, and executive functioning are the most frequently identified cognitive domains impacted by cancer. However, the prevalence and extent of impairment remains largely unknown due to marked differences in methodology, definitions of cognitive impairment, and the assessment measures used. Assessment of cognitive functioning is an important and necessary part of a comprehensive oncological care plan. Research is needed to establish a better understanding of cognitive changes and impairments associated with cancer so that optimal patient outcomes can be achieved. PMID:29497579

  7. Nutrition and cognitive impairment

    Science.gov (United States)

    Hernando-Requejo, Virgilio

    2016-07-12

    Dementia, closely linked to environmental predisposing factors such as diet, is a public health problem of increasing magnitude: currently there are more than 35 million patients with Alzheimer´s disease, and is expected to exceed 135 million by 2050. If we can delay the development of dementia 5 years will reduce its prevalence by 50%. Patients with dementia modify their diet, and it has been reported in them deficits, among others, of folic acid, vitamin B12, B6, C, E, A, D, K, beta carotene and omega 3 fatty acids, that must be resolved with proper diet and with extra contributions if needed in some cases. But to reduce, or at least delay, the prevalence of dementia we advocate prevention through proper diet from the beginning of life, an idea that is reinforced given that cardiovascular risk factors are related directly to the development of dementia. A lot of literature are available that, although with limits, allows us to make nutritional recommendations for preventing cognitive impairment. Better results are achieved when complete diets have been studied and considered over specific nutrients separately. Particularly, the Mediterranean diet has great interest in this disease, since it ensures a high intake of vegetables, fruits, nuts, legumes, cereals, fish and olive oil, and moderate intake of meat, dairy products and alcohol. We will focus more on this article in this type of diet.

  8. Aminoglycoside-induced and non-syndromic hearing loss is associated with the G7444A mutation in the mitochondrial COI/tRNASer(UCN) genes in two Chinese families

    International Nuclear Information System (INIS)

    Zhu Yi; Qian Yaping; Tang Xiaowen; Wang Jindan; Yang Li; Liao Zhisu; Li Ronghua; Ji Jinzhang; Li Zhiyuan; Chen Jianfu; Choo, Daniel I.; Lu Jianxin; Guan Minxin

    2006-01-01

    We report here the clinical, genetic, and molecular characterization of two Chinese families with aminoglycoside induced and non-syndromic hearing impairment. Clinical and genetic evaluations revealed the variable severity and age-of-onset in hearing impairment in these families. Strikingly, there were extremely low penetrances of hearing impairment in these Chinese families. Sequence analysis of the complete mitochondrial genomes in these pedigrees showed the distinct sets of mtDNA polymorphism, in addition to the identical G7444A mutation associated with hearing loss. Indeed, the G7444A mutation in the CO1 gene and the precursor of tRNA Ser(UCN) gene is present in homoplasmy only in the maternal lineage of those pedigrees but not other members of these families and 164 Chinese controls. Their mitochondrial genomes belong to the Eastern Asian haplogroups C5a and D4a, respectively. In fact, the occurrence of the G7444A mutation in these several genetically unrelated subjects affected by hearing impairment strongly indicates that this mutation is involved in the pathogenesis of hearing impairment. However, there was the absence of other functionally significant mtDNA mutations in two Chinese pedigrees carrying the G7444A mutation. Therefore, nuclear modifier gene(s) or aminoglycoside(s) may play a role in the phenotypic expression of the deafness-associated G7444A mutation in these Chinese pedigrees

  9. ENPP1 Mutation Causes Recessive Cole Disease by Altering Melanogenesis.

    Science.gov (United States)

    Chourabi, Marwa; Liew, Mei Shan; Lim, Shawn; H'mida-Ben Brahim, Dorra; Boussofara, Lobna; Dai, Liang; Wong, Pui Mun; Foo, Jia Nee; Sriha, Badreddine; Robinson, Kim Samirah; Denil, Simon; Common, John Ea; Mamaï, Ons; Ben Khalifa, Youcef; Bollen, Mathieu; Liu, Jianjun; Denguezli, Mohamed; Bonnard, Carine; Saad, Ali; Reversade, Bruno

    2018-02-01

    Cole disease is a genodermatosis of pigmentation following a strict dominant mode of inheritance. In this study, we investigated eight patients affected with an overlapping genodermatosis after recessive inheritance. The patients presented with hypo- and hyperpigmented macules over the body, resembling dyschromatosis universalis hereditaria in addition to punctuate palmoplantar keratosis. By homozygosity mapping and whole-exome sequencing, a biallelic p.Cys120Arg mutation in ectonucleotide pyrophosphatase/phosphodiesterase 1 (ENPP1) was identified in all patients. We found that this mutation, like those causing dominant Cole disease, impairs homodimerization of the ENPP1 enzyme that is mediated by its two somatomedin-B-like domains. Histological analysis revealed structural and molecular changes in affected skin that were likely to originate from defective melanocytes because keratinocytes do not express ENPP1. Consistently, RNA-sequencing analysis of patient-derived primary melanocytes revealed alterations in melanocyte development and in pigmentation signaling pathways. We therefore conclude that germline ENPP1 cysteine-specific mutations, primarily affecting the melanocyte lineage, cause a clinical spectrum of dyschromatosis, in which the p.Cys120Arg allele represents a recessive and more severe form of Cole disease. Copyright © 2017 The Authors. Published by Elsevier Inc. All rights reserved.

  10. CSB-PGBD3 Mutations Cause Premature Ovarian Failure.

    Directory of Open Access Journals (Sweden)

    Yingying Qin

    2015-07-01

    Full Text Available Premature ovarian failure (POF is a rare, heterogeneous disorder characterized by cessation of menstruation occurring before the age of 40 years. Genetic etiology is responsible for perhaps 25% of cases, but most cases are sporadic and unexplained. In this study, through whole exome sequencing in a non-consanguineous family having four affected members with POF and Sanger sequencing in 432 sporadic cases, we identified three novel mutations in the fusion gene CSB-PGBD3. Subsequently functional studies suggest that mutated CSB-PGBD3 fusion protein was impaired in response to DNA damage, as indicated by delayed or absent recruitment to damaged sites. Our data provide the first evidence that mutations in the CSB-PGBD3 fusion protein can cause human disease, even in the presence of functional CSB, thus potentially explaining conservation of the fusion protein for 43 My since marmoset. The localization of the CSB-PGBD3 fusion protein to UVA-induced nuclear DNA repair foci further suggests that the CSB-PGBD3 fusion protein, like many other proteins that can cause POF, modulates or participates in DNA repair.

  11. Biallelic UFM1 and UFC1 mutations expand the essential role of ufmylation in brain development.

    Science.gov (United States)

    Nahorski, Michael S; Maddirevula, Sateesh; Ishimura, Ryosuke; Alsahli, Saud; Brady, Angela F; Begemann, Anaïs; Mizushima, Tsunehiro; Guzmán-Vega, Francisco J; Obata, Miki; Ichimura, Yoshinobu; Alsaif, Hessa S; Anazi, Shams; Ibrahim, Niema; Abdulwahab, Firdous; Hashem, Mais; Monies, Dorota; Abouelhoda, Mohamed; Meyer, Brian F; Alfadhel, Majid; Eyaid, Wafa; Zweier, Markus; Steindl, Katharina; Rauch, Anita; Arold, Stefan T; Woods, C Geoffrey; Komatsu, Masaaki; Alkuraya, Fowzan S

    2018-06-02

    The post-translational modification of proteins through the addition of UFM1, also known as ufmylation, plays a critical developmental role as revealed by studies in animal models. The recent finding that biallelic mutations in UBA5 (the E1-like enzyme for ufmylation) cause severe early-onset encephalopathy with progressive microcephaly implicates ufmylation in human brain development. More recently, a homozygous UFM1 variant was proposed as a candidate aetiology of severe early-onset encephalopathy with progressive microcephaly. Here, we establish a locus for severe early-onset encephalopathy with progressive microcephaly based on two families, and map the phenotype to a novel homozygous UFM1 mutation. This mutation has a significantly diminished capacity to form thioester intermediates with UBA5 and with UFC1 (the E2-like enzyme for ufmylation), with resulting impaired ufmylation of cellular proteins. Remarkably, in four additional families where eight children have severe early-onset encephalopathy with progressive microcephaly, we identified two biallelic UFC1 mutations, which impair UFM1-UFC1 intermediate formation with resulting widespread reduction of cellular ufmylation, a pattern similar to that observed with UFM1 mutation. The striking resemblance between UFM1- and UFC1-related clinical phenotype and biochemical derangements strongly argues for an essential role for ufmylation in human brain development. The hypomorphic nature of UFM1 and UFC1 mutations and the conspicuous depletion of biallelic null mutations in the components of this pathway in human genome databases suggest that it is necessary for embryonic survival, which is consistent with the embryonic lethal nature of knockout models for the orthologous genes.

  12. Histone Variant HTZ1 Shows Extensive Epistasis with, but Does Not Increase Robustness to, New Mutations

    Science.gov (United States)

    Richardson, Joshua B.; Uppendahl, Locke D.; Traficante, Maria K.; Levy, Sasha F.; Siegal, Mark L.

    2013-01-01

    Biological systems produce phenotypes that appear to be robust to perturbation by mutations and environmental variation. Prior studies identified genes that, when impaired, reveal previously cryptic genetic variation. This result is typically interpreted as evidence that the disrupted gene normally increases robustness to mutations, as such robustness would allow cryptic variants to accumulate. However, revelation of cryptic genetic variation is not necessarily evidence that a mutationally robust state has been made less robust. Demonstrating a difference in robustness requires comparing the ability of each state (with the gene perturbed or intact) to suppress the effects of new mutations. Previous studies used strains in which the existing genetic variation had been filtered by selection. Here, we use mutation accumulation (MA) lines that have experienced minimal selection, to test the ability of histone H2A.Z (HTZ1) to increase robustness to mutations in the yeast Saccharomyces cerevisiae. HTZ1, a regulator of chromatin structure and gene expression, represents a class of genes implicated in mutational robustness. It had previously been shown to increase robustness of yeast cell morphology to fluctuations in the external or internal microenvironment. We measured morphological variation within and among 79 MA lines with and without HTZ1. Analysis of within-line variation confirms that HTZ1 increases microenvironmental robustness. Analysis of between-line variation shows the morphological effects of eliminating HTZ1 to be highly dependent on the line, which implies that HTZ1 interacts with mutations that have accumulated in the lines. However, lines without HTZ1 are, as a group, not more phenotypically diverse than lines with HTZ1 present. The presence of HTZ1, therefore, does not confer greater robustness to mutations than its absence. Our results provide experimental evidence that revelation of cryptic genetic variation cannot be assumed to be caused by loss of

  13. Impact of mutations in Toll-like receptor pathway genes on esophageal carcinogenesis.

    Directory of Open Access Journals (Sweden)

    Daffolyn Rachael Fels Elliott

    2017-05-01

    Full Text Available Esophageal adenocarcinoma (EAC develops in an inflammatory microenvironment with reduced microbial diversity, but mechanisms for these influences remain poorly characterized. We hypothesized that mutations targeting the Toll-like receptor (TLR pathway could disrupt innate immune signaling and promote a microenvironment that favors tumorigenesis. Through interrogating whole genome sequencing data from 171 EAC patients, we showed that non-synonymous mutations collectively affect the TLR pathway in 25/171 (14.6%, PathScan p = 8.7x10-5 tumors. TLR mutant cases were associated with more proximal tumors and metastatic disease, indicating possible clinical significance of these mutations. Only rare mutations were identified in adjacent Barrett's esophagus samples. We validated our findings in an external EAC dataset with non-synonymous TLR pathway mutations in 33/149 (22.1%, PathScan p = 0.05 tumors, and in other solid tumor types exposed to microbiomes in the COSMIC database (10,318 samples, including uterine endometrioid carcinoma (188/320, 58.8%, cutaneous melanoma (377/988, 38.2%, colorectal adenocarcinoma (402/1519, 26.5%, and stomach adenocarcinoma (151/579, 26.1%. TLR4 was the most frequently mutated gene with eleven mutations in 10/171 (5.8% of EAC tumors. The TLR4 mutants E439G, S570I, F703C and R787H were confirmed to have impaired reactivity to bacterial lipopolysaccharide with marked reductions in signaling by luciferase reporter assays. Overall, our findings show that TLR pathway genes are recurrently mutated in EAC, and TLR4 mutations have decreased responsiveness to bacterial lipopolysaccharide and may play a role in disease pathogenesis in a subset of patients.

  14. Histone variant HTZ1 shows extensive epistasis with, but does not increase robustness to, new mutations.

    Directory of Open Access Journals (Sweden)

    Joshua B Richardson

    Full Text Available Biological systems produce phenotypes that appear to be robust to perturbation by mutations and environmental variation. Prior studies identified genes that, when impaired, reveal previously cryptic genetic variation. This result is typically interpreted as evidence that the disrupted gene normally increases robustness to mutations, as such robustness would allow cryptic variants to accumulate. However, revelation of cryptic genetic variation is not necessarily evidence that a mutationally robust state has been made less robust. Demonstrating a difference in robustness requires comparing the ability of each state (with the gene perturbed or intact to suppress the effects of new mutations. Previous studies used strains in which the existing genetic variation had been filtered by selection. Here, we use mutation accumulation (MA lines that have experienced minimal selection, to test the ability of histone H2A.Z (HTZ1 to increase robustness to mutations in the yeast Saccharomyces cerevisiae. HTZ1, a regulator of chromatin structure and gene expression, represents a class of genes implicated in mutational robustness. It had previously been shown to increase robustness of yeast cell morphology to fluctuations in the external or internal microenvironment. We measured morphological variation within and among 79 MA lines with and without HTZ1. Analysis of within-line variation confirms that HTZ1 increases microenvironmental robustness. Analysis of between-line variation shows the morphological effects of eliminating HTZ1 to be highly dependent on the line, which implies that HTZ1 interacts with mutations that have accumulated in the lines. However, lines without HTZ1 are, as a group, not more phenotypically diverse than lines with HTZ1 present. The presence of HTZ1, therefore, does not confer greater robustness to mutations than its absence. Our results provide experimental evidence that revelation of cryptic genetic variation cannot be assumed to be

  15. Detection of Deafness-Causing Mutations in the Greek Mitochondrial Genome

    Directory of Open Access Journals (Sweden)

    Haris Kokotas

    2011-01-01

    Full Text Available Mitochondrion harbors its own DNA, known as mtDNA, encoding certain essential components of the mitochondrial respiratory chain and protein synthesis apparatus. mtDNA mutations have an impact on cellular ATP production and many of them are undoubtedly a factor that contributes to sensorineural deafness, including both syndromic and non-syndromic forms. Hot spot regions for deafness mutations are the MTRNR1 gene, encoding the 12S rRNA, the MTTS1 gene, encoding the tRNA for Ser(UCN, and the MTTL1 gene, encoding the tRNA for Leu(UUR. We investigated the impact of mtDNA mutations in the Greek hearing impaired population, by testing a cohort of 513 patients suffering from childhood onset prelingual or postlingual, bilateral, sensorineural, syndromic or non-syndromic hearing loss of any degree for six mitochondrial variants previously associated with deafness. Screening involved the MTRNR1 961delT/insC and A1555G mutations, the MTTL1 A3243G mutation, and the MTTS1 A7445G, 7472insC and T7510C mutations. Although two patients were tested positive for the A1555G mutation, we failed to identify any subject carrying the 961delT/insC, A3243G, A7445G, 7472insC, or T7510C mutations. Our findings strongly support our previously raised conclusion that mtDNA mutations are not a major risk factor for sensorineural deafness in the Greek population.

  16. Fate of induced mutations in higher plants with special emphasis on sexually reproducing species

    International Nuclear Information System (INIS)

    Cornu, Andre

    1978-01-01

    A mutation induced in a plant somatic cell has to overcome quite many difficulties before being isolated and utilized as a marker in a mutated line. If induced in a meristem, three conditions must be fulfilled for the mutation to be transmitted to the subsequent generation: it must be compatible with normal cell multiplication, it must be located in a cell mass that will provide an inflorescence, and it must be in the sporogenetic layer (t2). Under these conditions, or if it is induced in a gamete or in a zygote, the mutation enters a first cycle of sexual reproduction. Meiosis and the subsequent haploid phase constitute severe screening steps for many chromosome aberrations. Studies on Petunia performed by means of marker genes show that male and female gametic viabilities are drastically impaired by deletions. However, a deficient chromosome can be transmitted when the losss of information is compensated for by homologous information as, for example, diploid gametes from tetraploids or disomic gametes resulting from non-disjunction. If partial or complete sterility, whether sporo- or gametophytic, is avoided, then the mutation can be transmitted to the next generation in heterozygous state. When becoming homozygous, the mutation may have effects such that its use can be most difficult. This is the case when this mutation causes rather early lethality or severe sterility. Thus, in higher plants, one faces several cases of powerful and efficient selection against mutations. On the basis of experiments carried out on Petunia, the per locus mutation rate of practical interest ranges between I and 5/10000M 1 plants. Practical conclusions are drawn about which organ should be treated, which mutagen at what dose should be used according to the scope of the research undertaken [fr

  17. A novel OPA1 mutation in a Chinese family with autosomal dominant optic atrophy

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Juanjuan; Yuan, Yimin; Lin, Bing; Feng, Hao; Li, Yan [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou 325027, Zhejiang (China); Dai, Xianning; Zhou, Huihui [Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou 325035, Zhejiang (China); Dong, Xujie [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou 325027, Zhejiang (China); Liu, Xiao-Ling, E-mail: lxl@mail.eye.ac.cn [School of Ophthalmology and Optometry, Wenzhou Medical College, Wenzhou 325027, Zhejiang (China); Guan, Min-Xin, E-mail: min-xin.guan@cchmc.org [Attardi Institute of Mitochondrial Biomedicine and Zhejiang Provincial Key Laboratory of Medical Genetics, School of Life Sciences, Wenzhou Medical College, Wenzhou 325035, Zhejiang (China); Institute of Genetics, Zhejiang University, Hangzhou, Zhejiang 310012 (China); Division of Human Genetics, Cincinnati Children' s Hospital Medical Center, OH 45229 (United States)

    2012-03-23

    Highlights: Black-Right-Pointing-Pointer We report the characterization of a four-generation large Chinese family with ADOA. Black-Right-Pointing-Pointer We find a new heterozygous mutation c.C1198G in OPA1 gene which may be a novel pathogenic mutation in this pedigree. Black-Right-Pointing-Pointer We do not find any mitochondrial DNA mutations associated with optic atrophy. Black-Right-Pointing-Pointer Other factors may also contribute to the phenotypic variability of ADOA in this pedigree. -- Abstract: A large four-generation Chinese family with autosomal dominant optic atrophy (ADOA) was investigated in the present study. Eight of the family members were affected in this pedigree. The affected family members exhibited early-onset and progressive visual impairment, resulting in mild to profound loss of visual acuity. The average age-at-onset was 15.9 years. A new heterozygous mutation c.C1198G was identified by sequence analysis of the 12th exon of the OPA1 gene. This mutation resulted in a proline to alanine substitution at codon 400, which was located in an evolutionarily conserved region. This missense mutation in the GTPase domain was supposed to result in a loss of function for the encoded protein and act through a dominant negative effect. No other mutations associated with optic atrophy were found in our present study. The c.C1198G heterozygous mutation in the OPA1 gene may be a novel key pathogenic mutation in this pedigree with ADOA. Furthermore, additional nuclear modifier genes, environmental factors, and psychological factors may also contribute to the phenotypic variability of ADOA in this pedigree.

  18. A novel OPA1 mutation in a Chinese family with autosomal dominant optic atrophy

    International Nuclear Information System (INIS)

    Zhang, Juanjuan; Yuan, Yimin; Lin, Bing; Feng, Hao; Li, Yan; Dai, Xianning; Zhou, Huihui; Dong, Xujie; Liu, Xiao-Ling; Guan, Min-Xin

    2012-01-01

    Highlights: ► We report the characterization of a four-generation large Chinese family with ADOA. ► We find a new heterozygous mutation c.C1198G in OPA1 gene which may be a novel pathogenic mutation in this pedigree. ► We do not find any mitochondrial DNA mutations associated with optic atrophy. ► Other factors may also contribute to the phenotypic variability of ADOA in this pedigree. -- Abstract: A large four-generation Chinese family with autosomal dominant optic atrophy (ADOA) was investigated in the present study. Eight of the family members were affected in this pedigree. The affected family members exhibited early-onset and progressive visual impairment, resulting in mild to profound loss of visual acuity. The average age-at-onset was 15.9 years. A new heterozygous mutation c.C1198G was identified by sequence analysis of the 12th exon of the OPA1 gene. This mutation resulted in a proline to alanine substitution at codon 400, which was located in an evolutionarily conserved region. This missense mutation in the GTPase domain was supposed to result in a loss of function for the encoded protein and act through a dominant negative effect. No other mutations associated with optic atrophy were found in our present study. The c.C1198G heterozygous mutation in the OPA1 gene may be a novel key pathogenic mutation in this pedigree with ADOA. Furthermore, additional nuclear modifier genes, environmental factors, and psychological factors may also contribute to the phenotypic variability of ADOA in this pedigree.

  19. A framework for communication between visually impaired, hearing impaired and speech impaired using arduino

    Science.gov (United States)

    Sujatha, R.; Khandelwa, Prakhar; Gupta, Anusha; Anand, Nayan

    2017-11-01

    A long time ago our society accepted the notion of treating people with disabilities not as unviable and disabled but as differently-abled, recognizing their skills beyond their disabilities. The next step has to be taken by our scientific community, that is, to normalize lives of the people with disabilities and make it so as if they are no different to us. The primary step in this direction would be to normalize communication between people. People with an impaired speech or impaired vision or impaired hearing face difficulties while having a casual conversation with others. Any form of communication feels so strenuous that the impaired end up communicating just the important information and avoid a casual conversation. To normalize conversation between the impaired we need a simple and compact device which facilitates the conversation by providing the information in the desired form.

  20. Energy parasites trigger oncogene mutation

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Jiří; Pokorný, Jan; Jandová, Anna; Kobilková, J.; Vrba, J.; Vrba, J. jr.

    2016-01-01

    Roč. 92, č. 10 (2016), s. 577-582 ISSN 0955-3002 R&D Projects: GA ČR GA16-12757S Institutional support: RVO:68378271 ; RVO:67985882 Keywords : cancer initiation * cell-mediated immunity * coherent electromagnetic states * genome somatic mutation * LDH virus * parasitic energy consumption Subject RIV: BO - Biophysics Impact factor: 1.992, year: 2016

  1. Induced mutation of Dendrobium orchid

    International Nuclear Information System (INIS)

    Sakinah Ariffin; Mohd Nazir Basiran

    2000-01-01

    Dendrobiiim orchids serve as the main orchid cut flower export of Malaysia. The wide range of colour and forms presently available in the market are obtained through hybridisation. Induced mutation breeding program was initiated on a commercial variety Dendrobium 'Sonia Kai' to explore the possibilities of obtaining new colour and forms. Matured seeds from self pollination were cultured and irradiated at 35 Gy at the protocorm-like bodies (PLBS) stage. Selection of induced mutations was done after the first flowering of the plants regenerated from the irradiated protocorms. Results showed changes in flower colour, shape and size. Most of these chances are expressed in different combinations in the petals, sepals and lip of the flowers. Thus, resulting. in a very wide spectrum of mutations. Some of these chances are not stable. To date, mutants that showed stable characteristics changes are grouped into 11 categories based on flower colour and form. These results show that the combination of its vitro technique and induced mutation can be applied in orchid breeding to produce new interesting and attractive variety for the market

  2. Mutational specificity of SOS mutagenesis

    International Nuclear Information System (INIS)

    Kato, Takeshi

    1986-01-01

    In an approach to the isolation of mutants of E. coli unable to produce mutations by ultraviolet light, the author has found new umuC-mutants. Their properties could be explained by ''SOS hypothesis of Radman and Witkin'', which has now been justified by many investigators. Analysis of the umuC region of E. coli chromosome cloned in pSK 100 has led to the conclusion that two genes, umuD and umuC, having the capacity of mutation induction express in the same mechanism as that of SOS genes, which is known to be inhibited by LexA protein bonding to ''SOS box'' found at promotor region. Suppressor analysis for mutational specificity has revealed: (i) umuDC-independent mutagens, such as EMS and (oh) 4 Cy, induce selected base substitution alone; and (ii) umuDC-dependent mutagens, such as X-rays and gamma-rays, induce various types of base substitution simultaneously, although they have mutational specificity. In the umuDC-dependent processes of basechange mutagenesis, the spectra of base substitution were a mixture of base substitution reflecting the specific base damages induced by individual mutagens and nonspecific base substitution. In conclusion, base substitution plays the most important role in umuDC-dependent mutagenesis, although mutagenesis of umuDC proteins remains uncertain. (Namekawa, K.)

  3. Mutated genes as research tool

    International Nuclear Information System (INIS)

    1981-01-01

    Green plants are the ultimate source of all resources required for man's life, his food, his clothes, and almost all his energy requirements. Primitive prehistoric man could live from the abundance of nature surrounding him. Man today, dominating nature in terms of numbers and exploiting its limited resources, cannot exist without employing his intelligence to direct natural evolution. Plant sciences, therefore, are not a matter of curiosity but an essential requirement. From such considerations, the IAEA and FAO jointly organized a symposium to assess the value of mutation research for various kinds of plant science, which directly or indirectly might contribute to sustaining and improving crop production. The benefit through developing better cultivars that plant breeders can derive from using the additional genetic resources resulting from mutation induction has been assessed before at other FAO/IAEA meetings (Rome 1964, Pullman 1969, Ban 1974, Ibadan 1978) and is also monitored in the Mutation Breeding Newsletter, published by IAEA twice a year. Several hundred plant cultivars which carry economically important characters because their genes have been altered by ionizing radiation or other mutagens, are grown by farmers and horticulturists in many parts of the world. But the benefit derived from such mutant varieties is without any doubt surpassed by the contribution which mutation research has made towards the advancement of genetics. For this reason, a major part of the papers and discussions at the symposium dealt with the role induced-mutation research played in providing insight into gene action and gene interaction, the organization of genes in plant chromosomes in view of homology and homoeology, the evolutionary role of gene duplication and polyploidy, the relevance of gene blocks, the possibilities for chromosome engineering, the functioning of cytroplasmic inheritance and the genetic dynamics of populations. In discussing the evolutionary role of

  4. Molecular genetic analysis of the F11 gene in 14 Turkish patients with factor XI deficiency: identification of novel and recurrent mutations and their inheritance within families.

    Science.gov (United States)

    Colakoglu, Seyma; Bayhan, Turan; Tavil, Betül; Keskin, Ebru Yılmaz; Cakir, Volkan; Gümrük, Fatma; Çetin, Mualla; Aytaç, Selin; Berber, Ergul

    2018-01-01

    Factor XI (FXI) deficiency is an autosomal bleeding disease associated with genetic defects in the F11 gene which cause decreased FXI levels or impaired FXI function. An increasing number of mutations has been reported in the FXI mutation database, most of which affect the serine protease domain of the protein. FXI is a heterogeneous disorder associated with a variable bleeding tendency and a variety of causative F11 gene mutations. The molecular basis of FXI deficiency in 14 patients from ten unrelated families in Turkey was analysed to establish genotype-phenotype correlations and inheritance of the mutations in the patients' families. Fourteen index cases with a diagnosis of FXI deficiency and family members of these patients were enrolled into the study. The patients' F11 genes were amplified by polymerase chain reaction and subjected to direct DNA sequencing analysis. The findings were analysed statistically using bivariate correlations, Pearson's correlation coefficient and the nonparametric Mann-Whitney test. Direct DNA sequencing analysis of the F11 genes revealed that all of the 14 patients had a F11 gene mutation. Eight different mutations were identified in the apple 1, apple 2 or serine protease domains, except one which was a splice site mutation. Six of the mutations were recurrent. Two of the mutations were novel missense mutations, p.Val522Gly and p.Cys581Arg, within the catalytic domain. The p.Trp519Stop mutation was observed in two families whereas all the other mutations were specific to a single family. Identification of mutations confirmed the genetic heterogeneity of FXI deficiency. Most of the patients with mutations did not have any bleeding complications, whereas some had severe bleeding symptoms. Genetic screening for F11 gene mutations is important to decrease the mortality and morbidity rate associated with FXI deficiency, which can be life-threatening if bleeding occurs in tissues with high fibrinolytic activity.

  5. Distinct mutations in STXBP2 are associated with variable clinical presentations in patients with familial hemophagocytic lymphohistiocytosis type 5 (FHL5)

    DEFF Research Database (Denmark)

    Pagel, Julia; Beutel, Karin; Lehmberg, Kai

    2012-01-01

    the genetic and clinical spectrum of FHL5, we analyzed a cohort of 185 patients with suspected FHL for mutations in STXBP2. We detected biallelic mutations in 37 patients from 28 families of various ethnic origins. Missense mutations and mutations affecting 1 of the exon 15 splice sites were the predominant...... changes detectable in this cohort. Patients with exon 15 splice-site mutations (n = 13) developed clinical manifestations significantly later than patients with other mutations (median age, 4.1 year vs 2 months) and showed less severe impairment of degranulation and cytotoxic function of NK cells and CTLs....... Patients with FHL5 showed several atypical features, including sensorineural hearing deficit, abnormal bleeding, and, most frequently, severe diarrhea that was only present in early-onset disease. In conclusion, we report the largest cohort of patients with FHL5 so far, describe an extended disease...

  6. Mutations in myosin VIIA (MYO7A) and usherin (USH2A) in Spanish patients with Usher syndrome types I and II, respectively.

    Science.gov (United States)

    Nájera, Carmen; Beneyto, Magdalena; Blanca, José; Aller, Elena; Fontcuberta, Ana; Millán, José María; Ayuso, Carmen

    2002-07-01

    Usher syndrome is an autosomal recessive disorder characterized by congenital hearing impairment and retinitis pigmentosa. Three clinical types are known (USH1, USH2 and USH3), and there is an extensive genetic heterogeneity, with at least ten genes implicated. The most frequently mutated genes are MYO7A, which causes USH1B, and usherin, which causes USH2A. We carried out a mutation analysis of these two genes in the Spanish population. Analysis of the MYO7A gene in patients from 30 USH1 families and sporadic cases identified 32% of disease alleles, with mutation Q821X being the most frequent. Most of the remaining variants are private mutations. With regard to USH2, mutation 2299delG was detected in 25% of the Spanish patients. Altogether the mutations detected in USH2A families account for 23% of the disease alleles. Copyright 2002 Wiley-Liss, Inc.

  7. Radiation-induced mutation at minisatellite loci

    International Nuclear Information System (INIS)

    Dubrova, Y.E.; Nesterov, V.N.; Krouchinsky, N.G.

    1997-01-01

    We are studying the radiation-induced increase of mutation rate in minisatellite loci in mice and humans. Minisatellite mutations were scored by multilocus DNA fingerprint analysis in the progeny of γ-irradiated and non-irradiated mice. The frequency of mutation in offspring of irradiated males was 1.7 higher that in the control group. Germline mutation at human minisatellite loci was studied among children born in heavily polluted areas of the Mogilev district of Belarus after the Chernobyl accident and in a control population. The frequency of mutation assayed both by DNA fingerprinting and by eight single locus probes was found to be two times higher in the exposed families than in the control group. Furthermore, mutation rate was correlated with the parental radiation dose for chronic exposure 137 Cs, consistent with radiation-induction of germline mutation. The potential use of minisatellites in monitoring germline mutation in humans will be discussed

  8. Recurrent LDL-receptor mutation causes familial ...

    African Journals Online (AJOL)

    1995-05-05

    May 5, 1995 ... 3. eaudet . New. Recurrent LDL-receptor mutation causes familial hypercholesterolaemia in ... amplification refractory mutation system (ARMS)" and single- strand conformation .... Location. Afrikaner. Mixed race. ApaLl.

  9. Manual on mutation breeding. 2. ed.

    International Nuclear Information System (INIS)

    1977-01-01

    The manual is a compilation of work done on the use of induced mutations in plant breeding, and presents general methods and techniques in this field. The use of chemical mutagens and ionizing radiations (X-rays, gamma rays, α- and β-particles, protons, neutrons) are described as well as the effects of these mutagens. The different types of mutations achieved can be divided into genome mutations, chromosome mutations and extra nuclear mutations. Separate chapters deal with mutation techniques in breeding seed-propagated species and asexually propagated plants (examples of development of cultivars given). Plant characters which can be improved by mutation breeding include yield, ripening time, growth habit, disease resistance and tolerance to environmental factors (temperature, salinity etc.). The use of mutagens for some specific plant breeding problems is discussed and attention is also paid to somatic cell genetics in connection with induced mutations. The manual contains a comprehensive bibliography (60 p. references) and a subject index

  10. Cognitive impairment in elderly women

    DEFF Research Database (Denmark)

    Rasmussen, Henrik Berg; Bagger, Yu Z; Tankó, László B

    2006-01-01

    BACKGROUND: A variety of factors contribute to the development of cognitive impairment in elderly people. Previous studies have focused upon a single or a few risk factors. In this study we assessed and compared the significance of a wide variety of potential risk factors for cognitive impairment...... in postmenopausal women. METHODS: A total of 208 pairs of elderly women (mean age = 73.2 years) were examined in a cross-sectional case-control study. Each pair consisted of a case (with impaired cognition) and a control subject matched by age and educational status. Cognitive functions were determined using...

  11. Identification of a novel EYA1 splice-site mutation in a Danish branchio-oto-renal syndrome family

    DEFF Research Database (Denmark)

    Henriksen, Ann Marie; Tümer, Zeynep; Tommerup, Niels

    2004-01-01

    Branchio-oto-renal (BOR) syndrome is an autosomal dominant disorder characterized by variable clinical manifestations including branchial fistulae, preauricular pits, ear malformations, hearing impairment, and renal anomalies. BOR is caused by mutations in the genes EYA1 and SIX1. A Danish BOR...

  12. Mutation of Neuron-Specific Chromatin Remodeling Subunit BAF53b: Rescue of Plasticity and Memory by Manipulating Actin Remodeling

    Science.gov (United States)

    Ciernia, Annie Vogel; Kramár, Enikö A.; Matheos, Dina P.; Havekes, Robbert; Hemstedt, Thekla J.; Magnan, Christophe N.; Sakata, Keith; Tran, Ashley; Azzawi, Soraya; Lopez, Alberto; Dang, Richard; Wang, Weisheng; Trieu, Brian; Tong, Joyce; Barrett, Ruth M.; Post, Rebecca J.; Baldi, Pierre; Abel, Ted; Lynch, Gary; Wood, Marcelo A.

    2017-01-01

    Recent human exome-sequencing studies have implicated polymorphic Brg1-associated factor (BAF) complexes (mammalian SWI/SNF chromatin remodeling complexes) in several intellectual disabilities and cognitive disorders, including autism. However, it remains unclear how mutations in BAF complexes result in impaired cognitive function. Post-mitotic…

  13. A novel alpha-tropomyosin mutation associates with dilated and non-compaction cardiomyopathy and diminishes actin binding

    NARCIS (Netherlands)

    van de Meerakker, Judith B. A.; Christiaans, Imke; Barnett, Phil; Lekanne Deprez, Ronald H.; Ilgun, Aho; Mook, Olaf R. F.; Mannens, Marcel M. A. M.; Lam, Jan; Wilde, Arthur A. M.; Moorman, Antoon F. M.; Postma, Alex V.

    2013-01-01

    Dilated cardiomyopathy (DCM) is characterized by idiopathic dilatation and systolic contractile dysfunction of the ventricle(s) leading to an impaired systolic function. The origin of DCM is heterogeneous, but genetic transmission of the disease accounts for up to 50% of the cases. Mutations in

  14. Adaptive mutation: has the unicorn landed?

    Science.gov (United States)

    Foster, P L

    1998-01-01

    Reversion of an episomal Lac- allele during lactose selection has been studied as a model for adaptive mutation. Although recent results show that the mutations that arise during selection are not "adaptive" in the original sense, the mutagenic mechanism that produces these mutations may nonetheless be of evolutionary significance. In addition, a transient mutational state induced in a subpopulation of starving cells could provide a species with a mechanism for adaptive evolution. PMID:9560365

  15. Adaptive mutation: has the unicorn landed?

    Science.gov (United States)

    Foster, P L

    1998-04-01

    Reversion of an episomal Lac- allele during lactose selection has been studied as a model for adaptive mutation. Although recent results show that the mutations that arise during selection are not "adaptive" in the original sense, the mutagenic mechanism that produces these mutations may nonetheless be of evolutionary significance. In addition, a transient mutational state induced in a subpopulation of starving cells could provide a species with a mechanism for adaptive evolution.

  16. Urinary Tract Effects of HPSE2 Mutations

    OpenAIRE

    Stuart, H; Roberts, N; Hilton, E; McKenzie, E; Daly, S; Hadfield, K; Rahal, J; Gardiner, N; Tanley, S; Lewis, M; Sites, E; Angle, B; Alves, C; Lourenço, T; Rodrigues, M

    2015-01-01

    Urofacial syndrome (UFS) is an autosomal recessive congenital disease featuring grimacing and incomplete bladder emptying. Mutations of HPSE2, encoding heparanase 2, a heparanase 1 inhibitor, occur in UFS, but knowledge about the HPSE2 mutation spectrum is limited. Here, seven UFS kindreds with HPSE2 mutations are presented, including one with deleted asparagine 254, suggesting a role for this amino acid, which is conserved in vertebrate orthologs. HPSE2 mutations were absent in 23 non-neurog...

  17. Brain visual impairment in childhood: mini review

    OpenAIRE

    Kozeis, N

    2010-01-01

    Cerebral visual impairment (CVI) is one of the leading causes of severe visual impairment in childhood. This article was written to highlight any new knowledge related to cerebral visual impairment in childhood.

  18. Cerebral lactic acidosis correlates with neurological impairment in MELAS.

    Science.gov (United States)

    Kaufmann, P; Shungu, D C; Sano, M C; Jhung, S; Engelstad, K; Mitsis, E; Mao, X; Shanske, S; Hirano, M; DiMauro, S; De Vivo, D C

    2004-04-27

    To evaluate the role of chronic cerebral lactic acidosis in mitochondrial encephalomyopathy, lactic acidosis, and stroke-like episodes (MELAS). The authors studied 91 individuals from 34 families with MELAS and the A3243G point mutation and 15 individuals from two families with myoclonus epilepsy and ragged red fibers (MERRF) and the A8344G mutation. Subjects were divided into four groups. Paternal relatives were studied as controls (Group 1). The maternally related subjects were divided clinically into three groups: asymptomatic (no clinical evidence of neurologic disease) (Group 2), oligosymptomatic (neurologic symptoms but without the full clinical picture of MELAS or MERRF) (Group 3), and symptomatic (fulfilling MELAS or MERRF criteria) (Group 4). The authors performed a standardized neurologic examination, neuropsychological testing, MRS, and leukocyte DNA analysis in all subjects. The symptomatic and oligosymptomatic MELAS subjects had significantly higher ventricular lactate than the other groups. There was a significant correlation between degree of neuropsychological and neurologic impairment and cerebral lactic acidosis as estimated by ventricular MRS lactate levels. High levels of ventricular lactate, the brain spectroscopic signature of MELAS, are associated with more severe neurologic impairment.

  19. EDNRB mutations cause Waardenburg syndrome type II in the heterozygous state.

    Science.gov (United States)

    Issa, Sarah; Bondurand, Nadege; Faubert, Emmanuelle; Poisson, Sylvain; Lecerf, Laure; Nitschke, Patrick; Deggouj, Naima; Loundon, Natalie; Jonard, Laurence; David, Albert; Sznajer, Yves; Blanchet, Patricia; Marlin, Sandrine; Pingault, Veronique

    2017-05-01

    Waardenburg syndrome (WS) is a genetic disorder characterized by sensorineural hearing loss and pigmentation anomalies. The clinical definition of four WS types is based on additional features due to defects in structures mostly arising from the neural crest, with type I and type II being the most frequent. While type I is tightly associated to PAX3 mutations, WS type II (WS2) remains partly enigmatic with mutations in known genes (MITF, SOX10) accounting for only 30% of the cases. We performed exome sequencing in a WS2 index case and identified a heterozygous missense variation in EDNRB. Interestingly, homozygous (and very rare heterozygous) EDNRB mutations are already described in type IV WS (i.e., in association with Hirschsprung disease [HD]) and heterozygous mutations in isolated HD. Screening of a WS2 cohort led to the identification of an overall of six heterozygous EDNRB variations. Clinical phenotypes, pedigrees and molecular segregation investigations unraveled a dominant mode of inheritance with incomplete penetrance. In parallel, cellular and functional studies showed that each of the mutations impairs the subcellular localization of the receptor or induces a defective downstream signaling pathway. Based on our results, we now estimate EDNRB mutations to be responsible for 5%-6% of WS2. © 2017 Wiley Periodicals, Inc.

  20. Mutations in the TLR3 signaling pathway and beyond in adult patients with herpes simplex encephalitis.

    Science.gov (United States)

    Mørk, N; Kofod-Olsen, E; Sørensen, K B; Bach, E; Ørntoft, T F; Østergaard, L; Paludan, S R; Christiansen, M; Mogensen, T H

    2015-12-01

    Herpes simplex encephalitis (HSE) in children has previously been linked to defects in type I interferon production downstream of Toll-like receptor (TLR)3. In the present study, we used whole-exome sequencing to investigate the genetic profile of 16 adult patients with a history of HSE. We identified novel mutations in IRF3, TYK2 and MAVS, molecules involved in generating innate antiviral immune responses, which have not previously been associated with HSE. Moreover, data revealed mutations in TLR3, TRIF, TBK1 and STAT1 known to be associated with HSE in children but not previously described in adults. All discovered mutations were heterozygous missense mutations, the majority of which were associated with significantly decreased antiviral responses to HSV-1 infection and/or the TLR3 agonist poly(I:C) in patient peripheral blood mononuclear cells compared with controls. Altogether, this study demonstrates novel mutations in the TLR3 signaling pathway in molecules previously identified in children, suggesting that impaired innate immunity to HSV-1 may also increase susceptibility to HSE in adults. Importantly, the identification of mutations in innate signaling molecules not directly involved in TLR3 signaling suggests the existence of innate immunodeficiencies predisposing to HSE beyond the TLR3 pathway.

  1. Use of human tissue to assess the oncogenic activity of melanoma-associated mutations.

    Science.gov (United States)

    Chudnovsky, Yakov; Adams, Amy E; Robbins, Paul B; Lin, Qun; Khavari, Paul A

    2005-07-01

    Multiple genetic alterations occur in melanoma, a lethal skin malignancy of increasing incidence. These include mutations that activate Ras and two of its effector cascades, Raf and phosphoinositide 3-kinase (PI3K). Induction of Ras and Raf can be caused by active N-Ras and B-Raf mutants as well as by gene amplification. Activation of PI3K pathway components occurs by PTEN loss and by AKT3 amplification. Melanomas also commonly show impairment of the p16(INK4A)-CDK4-Rb and ARF-HDM2-p53 tumor suppressor pathways. CDKN2A mutations can produce p16(INK4A) and ARF protein loss. Rb bypass can also occur through activating CDK4 mutations as well as by CDK4 amplification. In addition to ARF deletion, p53 pathway disruption can result from dominant negative TP53 mutations. TERT amplification also occurs in melanoma. The extent to which these mutations can induce human melanocytic neoplasia is unknown. Here we characterize pathways sufficient to generate human melanocytic neoplasia and show that genetically altered human tissue facilitates functional analysis of mutations observed in human tumors.

  2. A Mouse Neurodegenerative Dynein Heavy Chain Mutation Alters Dynein Motility and Localization in Neurospora crassa

    Science.gov (United States)

    Sivagurunathan, Senthilkumar; Schnittker, Robert R.; Nandini, Swaran; Plamann, Michael D.; King, Stephen J.

    2013-01-01

    Cytoplasmic dynein is responsible for the transport and delivery of cargoes in organisms ranging from humans to fungi. Dysfunction of dynein motor machinery due to mutations in dynein or its activating complex dynactin can result in one of several neurological diseases in mammals. The mouse Legs at odd angles (Loa) mutation in the tail domain of the dynein heavy chain has been shown to lead to progressive neurodegeneration in mice. The mechanism by which the Loa mutation affects dynein function is just beginning to be understood. In this work, we generated the dynein tail mutation observed in Loa mice into the Neurospora crassa genome and utilized cell biological and complementing biochemical approaches to characterize how that tail mutation affected dynein function. We determined that the Loa mutation exhibits several subtle defects upon dynein function in N. crassa that were not seen in mice, including alterations in dynein localization, impaired velocity of vesicle transport, and in the biochemical properties of purified motors. Our work provides new information on the role of the tail domain on dynein function and points out areas of future research that will be of interest to pursue in mammalian systems. PMID:22991199

  3. Haploid rice plants in mutation studies

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, S [Institute of Radiation Breeding, Ministry of Agriculture and Forestry, Ohmiya, Ibaraki-ken (Japan)

    1970-03-01

    Studies were made on chlorophyll-deficient sectors and diploid-like sectors in haploid rice plants exposed to chronic gamma irradiation, and on germinal mutations in diploid strains derived from the haploid plants. The induction and elimination of somatic mutations in haploid plants and the occurrence of drastic germinal mutations in diploid strains from haploid plants are discussed. (author)

  4. Studies of human mutation rates: Progress report

    International Nuclear Information System (INIS)

    Neel, J.V.

    1988-01-01

    Progress was recorded between January 1 and July 1, 1987 on a project entitled ''Studies of Human Mutation Rates''. Studies underway include methodology for studying mutation at the DNA level, algorithms for automated analyses of two-dimensional polyacrylamide DNA gels, theoretical and applied population genetics, and studies of mutation frequency in A-bomb survivors

  5. Mitochondrial mutations drive prostate cancer aggression

    DEFF Research Database (Denmark)

    Hopkins, Julia F.; Sabelnykova, Veronica Y.; Weischenfeldt, Joachim

    2017-01-01

    Nuclear mutations are well known to drive tumor incidence, aggression and response to therapy. By contrast, the frequency and roles of mutations in the maternally inherited mitochondrial genome are poorly understood. Here we sequence the mitochondrial genomes of 384 localized prostate cancer...... in prostate cancer, and suggest interplay between nuclear and mitochondrial mutational profiles in prostate cancer....

  6. Electrophysiology in visually impaired children

    NARCIS (Netherlands)

    Genderen, Maria Michielde van

    2006-01-01

    Inherited retinal disorders and posterior visual pathway abnormalities are important causes of visual impairment in children. Visual electrophysiology often is indispensable in diagnosing these conditions. This thesis shows the wide range of use of pediatric electro-ophthalmology, and demonstrates

  7. Vacuolar Protein Sorting Genes in Parkinson's Disease: A Re-appraisal of Mutations Detection Rate and Neurobiology of Disease.

    Science.gov (United States)

    Gambardella, Stefano; Biagioni, Francesca; Ferese, Rosangela; Busceti, Carla L; Frati, Alessandro; Novelli, Giuseppe; Ruggieri, Stefano; Fornai, Francesco

    2016-01-01

    Mammalian retromers play a critical role in protein trans-membrane sorting from endosome to the trans-Golgi network (TGN). Recently, retromer alterations have been related to the onset of Parkinson's Disease (PD) since the variant p.Asp620Asn in VPS35 (Vacuolar Protein Sorting 35) was identified as a cause of late onset PD. This variant causes a primary defect in endosomal trafficking and retromers formation. Other mutations in VPS genes have been reported in both sporadic and familial PD. These mutations are less defined. Understanding the specific prevalence of all VPS gene mutations is key to understand the relevance of retromers impairment in the onset of PD. A number of PD-related mutations despite affecting different biochemical systems (autophagy, mitophagy, proteasome, endosomes, protein folding), all converge in producing an impairment in cell clearance. This may explain how genetic predispositions to PD may derive from slightly deleterious VPS mutations when combined with environmental agents overwhelming the clearance of the cell. This manuscript reviews genetic data produced in the last 5 years to re-define the actual prevalence of VPS gene mutations in the onset of PD. The prevalence of p.Asp620Asn mutation in VPS35 is 0.286 of familial PD. This increases up to 0.548 when considering mutations affecting all VPS genes. This configures mutations in VPS genes as the second most frequent autosomal dominant PD genotype. This high prevalence, joined with increased awareness of the role played by retromers in the neurobiology of PD, suggests environmentally-induced VPS alterations as crucial in the genesis of PD.

  8. Vacuolar Protein Sorting Genes in Parkinson's Disease: A Re-appraisal of Mutations Detection Rate and Neurobiology of Disease

    Science.gov (United States)

    Gambardella, Stefano; Biagioni, Francesca; Ferese, Rosangela; Busceti, Carla L.; Frati, Alessandro; Novelli, Giuseppe; Ruggieri, Stefano; Fornai, Francesco

    2016-01-01

    Mammalian retromers play a critical role in protein trans-membrane sorting from endosome to the trans-Golgi network (TGN). Recently, retromer alterations have been related to the onset of Parkinson's Disease (PD) since the variant p.Asp620Asn in VPS35 (Vacuolar Protein Sorting 35) was identified as a cause of late onset PD. This variant causes a primary defect in endosomal trafficking and retromers formation. Other mutations in VPS genes have been reported in both sporadic and familial PD. These mutations are less defined. Understanding the specific prevalence of all VPS gene mutations is key to understand the relevance of retromers impairment in the onset of PD. A number of PD-related mutations despite affecting different biochemical systems (autophagy, mitophagy, proteasome, endosomes, protein folding), all converge in producing an impairment in cell clearance. This may explain how genetic predispositions to PD may derive from slightly deleterious VPS mutations when combined with environmental agents overwhelming the clearance of the cell. This manuscript reviews genetic data produced in the last 5 years to re-define the actual prevalence of VPS gene mutations in the onset of PD. The prevalence of p.Asp620Asn mutation in VPS35 is 0.286 of familial PD. This increases up to 0.548 when considering mutations affecting all VPS genes. This configures mutations in VPS genes as the second most frequent autosomal dominant PD genotype. This high prevalence, joined with increased awareness of the role played by retromers in the neurobiology of PD, suggests environmentally-induced VPS alterations as crucial in the genesis of PD. PMID:27932943

  9. Spectrum of clinical presentations in familial hemophagocytic lymphohistiocytosis type 5 patients with mutations in STXBP2

    DEFF Research Database (Denmark)

    Meeths, Marie; Entesarian, Miriam; Al-Herz, Waleed

    2010-01-01

    Hemophagocytic lymphohistiocytosis (HLH) is an often-fatal hyperinflammatory syndrome characterized by fever, hepatosplenomegaly, cytopenia, and in some cases hemophagocytosis. Here, we describe the mutation analysis, clinical presentation, and functional analysis of natural killer (NK) cells...... (FHL), the clinical findings included colitis, bleeding disorders, and hypogammaglobulinemia in approximately one-third of the patients. Laboratory analysis revealed impairment of NK-cell degranulation and cytotoxic capacity. Interleukin-2 stimulation of lymphocytes in vitro rescued the NK cell......-associated functional defects. In conclusion, familial HLH type 5 is associated with a spectrum of clinical symptoms, which may be a reflection of impaired expression and function of Munc18-2 also in cells other than cytotoxic lymphocytes. Mutations in STXBP2 should thus also be considered in patients with clinical...

  10. Functional analysis of the novel TBX5 c.1333delC mutation resulting in an extended TBX5 protein

    Directory of Open Access Journals (Sweden)

    Ekman-Joelsson Britt-Marie

    2008-10-01

    Full Text Available Abstract Background Autosomal dominant Holt-Oram syndrome (HOS is caused by mutations in the TBX5 gene and is characterized by congenital heart and preaxial radial ray upper limb defects. Most of the TBX5 mutations found in patients with HOS cause premature truncation of the primary TBX5 transcript. TBX5 missense mutations alter the three-dimensional structure of the protein and result in failed nuclear localization or reduced binding to target DNA. In this study we present our functional analyses of the novel and unusual c.1333delC mutation found in a patient with classical HOS. Methods The functional impact of this novel mutation was assessed by investigating the intracellular localization of the resulting TBX5 protein and its ability to activate the expression of its downstream target ANF. Results The deletion of the cytosine is the first TBX5 frameshift mutation predicted to result in an elongated TBX5 protein with 74 miscoding amino acids and 62 supernumerary C-terminal amino acids. The c.1333delC mutation affects neither the nuclear localization, nor its colocalization with SALL4, but severely affects the activation of the ANF promoter. Conclusion The mutation c.1333delC does not locate within functional domains, but impairs the activation of the downstream target. This suggests that misfolding of the protein prevents its biological function.

  11. A rare CYP21A2 mutation in a congenital adrenal hyperplasia kindred displaying genotype-phenotype nonconcordance.

    Science.gov (United States)

    Khattab, Ahmed; Yuen, Tony; Al-Malki, Sultan; Yau, Mabel; Kazmi, Diya; Sun, Li; Harbison, Madeleine; Haider, Shozeb; Zaidi, Mone; New, Maria I

    2016-01-01

    Congenital adrenal hyperplasia (CAH) owing to 21-hydroxylase deficiency is caused by the autosomal recessive inheritance of mutations in the gene CYP21A2. CYP21A2 mutations lead to variable impairment of the 21-hydroxylase enzyme, which, in turn, is associated with three clinical phenotypes, namely, salt wasting, simple virilizing, and nonclassical CAH. However, it is known that a given mutation can associate with different clinical phenotypes, resulting in a high rate of genotype-phenotype nonconcordance. We aimed to study the genotype-phenotype nonconcordance in a family with three siblings affected with nonclassical CAH. All had hormonal evidence of nonclassical CAH, but this phenotype could not be explained by the genotype obtained from commercial CYP21A2 genetic testing, which revealed heterozygosity for the maternal 30 kb deletion mutation. We performed Sanger sequencing of the entire CYP21A2 gene in this family to search for a rare mutation that was not covered by commercial testing and found in the three siblings a second, rare c.1097G>A (p.R366H) mutation in exon 8. Computational modeling confirmed that this was a mild mutation consistent with nonclassical CAH. We recommend that sequencing of entire genes for rare mutations should be carried out when genotype-phenotype nonconcordance is observed in patients with autosomal recessive monogenic disorders, including CAH. © 2015 New York Academy of Sciences.

  12. Molecular and biochemical characterization of a unique mutation in CCS, the human copper chaperone to superoxide dismutase.

    Science.gov (United States)

    Huppke, Peter; Brendel, Cornelia; Korenke, Georg Christoph; Marquardt, Iris; Donsante, Anthony; Yi, Ling; Hicks, Julia D; Steinbach, Peter J; Wilson, Callum; Elpeleg, Orly; Møller, Lisbeth Birk; Christodoulou, John; Kaler, Stephen G; Gärtner, Jutta

    2012-08-01

    Copper (Cu) is a trace metal that readily gains and donates electrons, a property that renders it desirable as an enzyme cofactor but dangerous as a source of free radicals. To regulate cellular Cu metabolism, an elaborate system of chaperones and transporters has evolved, although no human Cu chaperone mutations have been described to date. We describe a child from a consanguineous family who inherited homozygous mutations in the SLC33A1, encoding an acetyl CoA transporter, and in CCS, encoding the Cu chaperone for superoxide dismutase. The CCS mutation, p.Arg163Trp, predicts substitution of a highly conserved arginine residue at position 163, with tryptophan in domain II of CCS, which interacts directly with superoxide dismutase 1 (SOD1). Biochemical analyses of the patient's fibroblasts, mammalian cell transfections, immunoprecipitation assays, and Lys7Δ (CCS homolog) yeast complementation support the pathogenicity of the mutation. Expression of CCS was reduced and binding of CCS to SOD1 impaired. As a result, this mutation causes reduced SOD1 activity and may impair other mechanisms important for normal Cu homeostasis. CCS-Arg163Trp represents the primary example of a human mutation in a gene coding for a Cu chaperone. © 2012 Wiley Periodicals, Inc.

  13. Normosmic idiopathic hypogonadotrophic hypogonadism due to a rare KISS1R gene mutation

    Directory of Open Access Journals (Sweden)

    N Chelaghma

    2018-04-01

    Full Text Available Hypogonadotrophic hypogonadism is due to impaired or reduced gonadotrophin secretion from the pituitary gland. In the absence of any anatomical or functional lesions of the pituitary or hypothalamic gland, the hypogonadotrophic hypogonadism is referred to as idiopathic hypogonadotrophic hypogonadism (IHH. We present a case of a young lady born to consanguineous parents who was found to have IHH due to a rare gene mutation.

  14. A novel UBE2A mutation causes X-linked intellectual disability type Nascimento.

    Science.gov (United States)

    Tsurusaki, Yoshinori; Ohashi, Ikuko; Enomoto, Yumi; Naruto, Takuya; Mitsui, Jun; Aida, Noriko; Kurosawa, Kenji

    2017-01-01

    X-linked intellectual disability (ID) type Nascimento (MIM #300860), also known as ubiquitin-conjugating enzyme E2 A (UBE2A) deficiency syndrome, is a congenital malformation syndrome characterized by moderate to severe ID, speech impairment, dysmorphic facial features, genital anomalies and skin abnormalities. Here, we report a Japanese patient with severe ID and congenital cataract. We identified a novel hemizygous mutation (c.76G>A, p.Gly26Arg) in UBE2A by whole-exome sequencing.

  15. Radiation induced chlorophyll mutations in rice

    International Nuclear Information System (INIS)

    Bari, G.; Mustafa, G.; Soomro, A.M.; Baloch, A.W.

    1985-01-01

    Air dried grains of four local varieties of rice were treated with gamma-rays and fast neutrons for determining their mutagenic effectiveness through the occurence of chlorophyll mutations. Fast neutrons were more effective in inducing chlorophyll mutations and the rice variety Basmati 370 produced maximum number of mutations followed by varieties Sonahri Sugdasi, Jajai 77 and Sada Gulab. The highest frequency of chlorophyll mutations was that of albina types followed by striata types. The xantha, viridis and tigrina types of mutations were less frequent. (authors)

  16. Mutation Clusters from Cancer Exome.

    Science.gov (United States)

    Kakushadze, Zura; Yu, Willie

    2017-08-15

    We apply our statistically deterministic machine learning/clustering algorithm *K-means (recently developed in https://ssrn.com/abstract=2908286) to 10,656 published exome samples for 32 cancer types. A majority of cancer types exhibit a mutation clustering structure. Our results are in-sample stable. They are also out-of-sample stable when applied to 1389 published genome samples across 14 cancer types. In contrast, we find in- and out-of-sample instabilities in cancer signatures extracted from exome samples via nonnegative matrix factorization (NMF), a computationally-costly and non-deterministic method. Extracting stable mutation structures from exome data could have important implications for speed and cost, which are critical for early-stage cancer diagnostics, such as novel blood-test methods currently in development.

  17. Gene mutations in hepatocellular adenomas

    DEFF Research Database (Denmark)

    Raft, Marie B; Jørgensen, Ernö N; Vainer, Ben

    2015-01-01

    is associated with bi-allelic mutations in the TCF1 gene and morphologically has marked steatosis. β-catenin activating HCA has increased activity of the Wnt/β-catenin pathway and is associated with possible malignant transformation. Inflammatory HCA is characterized by an oncogene-induced inflammation due...... to alterations in the Janus kinase/signal transducer and activator of transcription (JAK/STAT) pathway. In the diagnostic setting, sub classification of HCA is based primarily on immunohistochemical analyzes, and has had an increasing impact on choice of treatment and individual prognostic assessment....... This review offers an overview of the reported gene mutations associated with hepatocellular adenomas together with a discussion of the diagnostic and prognostic value....

  18. Novel compound heterozygous mutations in MYO7A in a Chinese family with Usher syndrome type 1.

    Science.gov (United States)

    Liu, Fei; Li, Pengcheng; Liu, Ying; Li, Weirong; Wong, Fulton; Du, Rong; Wang, Lei; Li, Chang; Jiang, Fagang; Tang, Zhaohui; Liu, Mugen

    2013-01-01

    To identify the disease-causing mutation(s) in a Chinese family with autosomal recessive Usher syndrome type 1 (USH1). An ophthalmic examination and an audiometric test were conducted to ascertain the phenotype of two affected siblings. The microsatellite marker D11S937, which is close to the candidate gene MYO7A (USH1B locus), was selected for genotyping. From the DNA of the proband, all coding exons and exon-intron boundaries of MYO7A were sequenced to identify the disease-causing mutation(s). Restriction fragment length polymorphism (RFLP) analysis was performed to exclude the alternative conclusion that the mutations are non-pathogenic rare polymorphisms. Based on severe hearing impairment, unintelligible speech, and retinitis pigmentosa, a clinical diagnosis of Usher syndrome type 1 was made. The genotyping results did not exclude the USH1B locus, which suggested that the MYO7A gene was likely the gene associated with the disease-causing mutation(s) in the family. With direct DNA sequencing of MYO7A, two novel compound heterozygous mutations (c.3742G>A and c.6051+1G>A) of MYO7A were identified in the proband. DNA sequence analysis and RFLP analysis of other family members showed that the mutations cosegregated with the disease. Unaffected members, including the parents, uncle, and sister of the proband, carry only one of the two mutations. The mutations were not present in the controls (100 normal Chinese subjects=200 chromosomes) according to the RFLP analysis. In this study, we identified two novel mutations, c.3742G>A (p.E1248K) and c.6051+1G>A (donor splice site mutation in intron 44), of MYO7A in a Chinese non-consanguineous family with USH1. The mutations cosegregated with the disease and most likely cause the phenotype in the two affected siblings who carry these mutations compound heterozygously. Our finding expands the mutational spectrum of MYO7A.

  19. Higher incidence of mild cognitive impairment in familial hypercholesterolemia

    Science.gov (United States)

    Zambón, D.; Quintana, M.; Mata, P.; Alonso, R.; Benavent, J.; Cruz-Sánchez, F.; Gich, J.; Pocoví, M.; Civeira, F.; Capurro, S.; Bachman, D.; Sambamurti, K.; Nicholas, J.; Pappolla, M. A.

    2010-01-01

    Objective Hypercholesterolemia is an early risk factor for Alzheimer’s disease. Low density lipoprotein (LDL) receptors may be involved in this disorder. Our objective was to determine the risk of mild cognitive impairment in a population of patients with heterozygous familial hypercholesterolemia, a condition involving LDL receptors dysfunction and life long hypercholesterolemia. Methods Using a cohort study design, patients with (N=47) meeting inclusion criteria and comparison patients without familial hypercholesterolemia (N=70) were consecutively selected from academic specialty and primary care clinics respectively. All patients were older than 50 years. Those with disorders which could impact cognition, including history of stroke or transient ischemic attacks, were excluded from both groups. Thirteen standardized neuropsychological tests were performed in all subjects. Mutational analysis was performed in patients with familial hypercholesterolemia and brain imaging was obtained in those with familial hypercholesterolemia and mild cognitive impairment. Results Patients with familial hypercholesterolemia showed a very high incidence of mild cognitive impairment compared to those without familial hypercholesterolemia (21.3% vs. 2.9%; p = 0.00). This diagnosis was unrelated to structural pathology or white matter disease. There were significant differences between the familial hypercholesterolemia and the no-familial hypercholesterolemia groups in several cognitive measures, all in the direction of worse performance for familial hypercholesterolemia patients, independent of apoE4 or apoE2 status. Conclusions Because prior studies have shown that older patients with sporadic hypercholesterolemia do not show higher incidence of mild cognitive impairment, the findings presented here suggest that early exposure to elevated cholesterol or LDL receptors dysfunction may be risk factors for mild cognitive impairment. PMID:20193836

  20. Inheritance of a new albino mutation in Brazilian free-range black chickens

    Directory of Open Access Journals (Sweden)

    W Jorge

    2008-09-01

    Full Text Available A genetically recessive albino mutation, which inhibits pigment development in the eyes, skin, and feathers of domestic chickens from Brazil, is described. This mutation appeared in a flock of completely black chickens of a private breeder. There are no information on the origin, breed, or specific line of the birds. Pigment inhibition is apparently complete in the feathers and eyes. Bird sight is very impaired, but no histological examination was carried out. Ratios obtained in F2 and backcrossed birds indicate that a single autosomal recessive gene is responsible for the condition. The data suggest that the absence of melanin in the eyes, skin, and feathers (symbol cc is a mutation of the pigmented C wild gene.

  1. Stratum corneum lipids, skin barrier function and filaggrin mutations in patients with atopic eczema

    DEFF Research Database (Denmark)

    Høgh, Julie Kaae; Hellgren, Lars; Jungersted, JM

    2010-01-01

    chromatography. In addition, TEWL, erythema, skin hydration and pH were measured. In 27 of the 49 individuals, a 24-h irritation patch test with sodium lauryl sulphate was performed. For the analysis, both the AD group and the control group were stratified by FLG mutation status (FLGmut/FLGwt). Results......Background: Prior to the discovery of filaggrin (FLG) mutations, evidence for an impaired skin barrier in atopic dermatitis (AD) has been documented, and changes in ceramide profile, altered skin pH and increased trans-epidermal water loss (TEWL) in patients with AD have been reported. Until now......, no studies have analysed stratum corneum (SC) lipids combined with skin barrier parameters in subjects of known FLG genotype. Methods: A cohort of 49 German individuals genotyped for the most common FLG mutations (R501X, 2282del4) had SC samples taken for lipid analysis by high-performance thin layer...

  2. Mutation breeding newsletter. No. 41

    International Nuclear Information System (INIS)

    1994-07-01

    This newsletter contains short descriptions of research methods for the use of radiation to induce mutations and facilitate plant breeding. This method is used to develop species of plants that can survive in harsh climates and thus provide a food supply for humans and animals. Some of the mutants discussed include a salt tolerant barley, a disease resistant shrub, a cold tolerant chickpea, a highly productive Canavalia virosa and productive tomato. Refs, figs and tabs

  3. The condensed mutation in sunflower

    International Nuclear Information System (INIS)

    Leclercq, P.

    1978-01-01

    Three inbred lines of sunflower were treated with gamma rays. In the progeny of one of these lines, the desired dwarf mutation appeared with a high frequency (23%). The dwarfing was accompanied by various undesirable characteristics (lateness, poor seed production, etc.), for which correction through genetic diversification and selection is in progress. The ratio capitulum diameter/stem height has increased from 1/8 up to 1/3 [fr

  4. Dystypia: isolated typing impairment without aphasia, apraxia or visuospatial impairment.

    Science.gov (United States)

    Otsuki, Mika; Soma, Yoshiaki; Arihiro, Shoji; Watanabe, Yoshimasa; Moriwaki, Hiroshi; Naritomi, Hiroaki

    2002-01-01

    We report a 60-year-old right-handed Japanese man who showed an isolated persistent typing impairment without aphasia, agraphia, apraxia or any other neuropsychological deficit. We coined the term 'dystypia' for this peculiar neuropsychological manifestation. The symptom was caused by an infarction in the left frontal lobe involving the foot of the second frontal convolution and the frontal operculum. The patient's typing impairment was not attributable to a disturbance of the linguistic process, since he had no aphasia or agraphia. The impairment was not attributable to the impairment of the motor execution process either, since he had no apraxia. Thus, his typing impairment was deduced to be based on a disturbance of the intermediate process where the linguistic phonological information is converted into the corresponding performance. We hypothesized that there is a specific process for typing which branches from the motor programming process presented in neurolinguistic models. The foot of the left second frontal convolution and the operculum may play an important role in the manifestation of 'dystypia'. Copyright 2002 S. Karger AG, Basel

  5. A novel A792D mutation in the CSF1R gene causes hereditary diffuse leukoencephalopathy with axonal spheroids characterized by slow progression

    Directory of Open Access Journals (Sweden)

    Sakiho Ueda

    2015-03-01

    Full Text Available Hereditary diffuse leukoencephalopathy with spheroids (HDLS is an autosomal dominant white matter disease that causes adult-onset cognitive impairment. The clinical manifestations are a variable combination of personality and behavioral changes, cognitive decline, parkinsonism, spasticity, and epilepsy. In 2012, mutations in the gene encoding colony stimulating factor 1 receptor (CSF1R were identified as the cause of HDLS. As the numbers of reported mutations are limited, the understanding of whole pathogenesis needs accumulation of disease-causing mutations with detailed clinical descriptions. We describe a Japanese family with autosomal dominant adult-onset cognitive impairment and characteristic white matter lesions. Genetic testing revealed a novel p.A792D mutation in the tyrosine kinase domain of CSF1R in two affected family members. The symptom profile of the present cases mostly matched the previously reported cases, with the notable exceptions of late-onset and long disease duration.

  6. Rare beneficial mutations can halt Muller's ratchet

    Science.gov (United States)

    Balick, Daniel; Goyal, Sidhartha; Jerison, Elizabeth; Neher, Richard; Shraiman, Boris; Desai, Michael

    2012-02-01

    In viral, bacterial, and other asexual populations, the vast majority of non-neutral mutations are deleterious. This motivates the application of models without beneficial mutations. Here we show that the presence of surprisingly few compensatory mutations halts fitness decay in these models. Production of deleterious mutations is balanced by purifying selection, stabilizing the fitness distribution. However, stochastic vanishing of fitness classes can lead to slow fitness decay (i.e. Muller's ratchet). For weakly deleterious mutations, production overwhelms purification, rapidly decreasing population fitness. We show that when beneficial mutations are introduced, a stable steady state emerges in the form of a dynamic mutation-selection balance. We argue this state is generic for all mutation rates and population sizes, and is reached as an end state as genomes become saturated by either beneficial or deleterious mutations. Assuming all mutations have the same magnitude selective effect, we calculate the fraction of beneficial mutations necessary to maintain the dynamic balance. This may explain the unexpected maintenance of asexual genomes, as in mitochondria, in the presence of selection. This will affect in the statistics of genetic diversity in these populations.

  7. Rare and unexpected beta thalassemic mutations in Qazvin ...

    African Journals Online (AJOL)

    About 13 beta-globin mutations encompass 70 - 90% of mutation spectrum in Iran. These mutations are called common beta-globin mutations. The rest are rare or unknown mutations. The objective of this study was to identify and describe rare or unknown beta-globin mutations in Qazvin province. EDTAcontaining venous ...

  8. Rare and unexpected beta thalassemic mutations in Qazvin ...

    African Journals Online (AJOL)

    STORAGESEVER

    2010-01-04

    Jan 4, 2010 ... About 13 beta-globin mutations encompass 70 - 90% of mutation spectrum in Iran. These mutations are called common beta-globin mutations. The rest are rare or unknown mutations. The objective of this study was to identify and describe rare or unknown beta-globin mutations in Qazvin province. EDTA-.

  9. Mutation breeding in vegetable crops

    International Nuclear Information System (INIS)

    Yamaguchi, Takashi

    1984-01-01

    Vegetables breed by seeds and vegetative organs. In main vegetables, the differentiation of clopping types, the adoption of monoculture and year-round production and shipment are carried out, adapting to various socio-economic and cultivation conditions. Protected agriculture has advanced mainly for fruit vegetables, and the seeds for sale have become almost hybrid varieties. Reflecting the situation like this, the demand for breeding is diversified and characteristic, and the case of applying mutation breeding seems to be many. The present status of the mutation breeding of vegetables is not yet well under way, but about 40 raised varieties have been published in the world. The characters introduced by induced mutation and irradiation were compact form, harvesting aptitude, the forms and properties of stems and leaves, anti-lodging property, the size, form and uniformity of fruits, male sterility and so on. The radiation sources used were mostly gamma ray or X-ray, but sometimes, combined irradiation was used. As the results obtained in Japan, burdocks as an example of gamma ray irradiation to seeds, tomatoes as an example of inducing the compound resistance against disease injury and lettuces as an example of internal beta irradiation are reported. (Kako, I.)

  10. Mutation Breeding for Crop Improvement

    International Nuclear Information System (INIS)

    Rajbir, S. Sangwan

    2017-01-01

    Chromosomes contain genes responsible of different traits of any organism. Induced mutation using chemical mutagens and radiation to modify molecular structure of plants played a major role in the development of high genetic variability and help develop new superior crop varieties. The Mutation Breeding is applicable to all plants and has generated lot of agronomically interesting mutants, both in vegetatively and seed propagated plants. The technique is easy but long and challenging to detect, isolate and characterize the mutant and gene. A specific dose of irradiation has to be used to obtain desired mutants. However, with modern molecular technique, the gene responsible for mutation can be identified. The CRISPR-Cas9 allows the removal of a specific gene which is responsible of unwanted trait and replacing it with a gene which induces a desired trait. There have been more than 2700 officially released mutant varieties from 170 different plant species in more than 60 countries throughout the world and A more participatory approach, involving all stakeholders in plant breeding, is needed to ensure that it is demand/farmers driven.

  11. Induced mutations in sesame breeding

    International Nuclear Information System (INIS)

    Ashri, A.

    2001-01-01

    The scope of induced mutations in sesame (Sesamum indicum L.) breeding is reviewed. So far in Egypt, India, Iraq, Rep. of Korea, and Sri Lanka, 14 officially released varieties have been developed through induced mutations: 12 directly and 2 through cross breeding (one using the 'dt45' induced mutant from Israel). For another variety released in China there are no details. The induced mutations approach was adopted primarily in order to obtain genetic variability that was not available in the germplasm collection. The mutagens commonly applied have been gamma rays, EMS and sodium azide. Sesame seeds can withstand high mutagen doses, and there are genotypic differences in sensitivity between varieties. The mutants induced in the above named countries and others include better yield, improved seed retention, determinate habit, modified plant architecture and size, more uniform and shorter maturation period, earliness, resistance to diseases, genic male sterility, seed coat color, higher oil content and modified fatty acids composition. Some of the induced mutants have already given rise to improved varieties, the breeding value of other mutants is now being assessed and still others can serve as useful markers in genetic studies and breeding programmes. (author)

  12. Germline APC mutations in hepatoblastoma.

    Science.gov (United States)

    Yang, Adeline; Sisson, Rebecca; Gupta, Anita; Tiao, Greg; Geller, James I

    2018-04-01

    Conflicting reports on the frequency of germline adenomatous polyposis coli (APC) gene mutations in patients with hepatoblastoma (HB) have called into question the clinical value of APC mutation testing on apparently sporadic HB. An Institutional Review Board approved retrospective review of clinical data collected from patients with HB who received APC testing at our institution was conducted. All HB patients seen at Cincinnati Children's Hospital Medical Center were eligible for testing. Potential genotype/phenotype correlations were assessed. As of July 2015, 29 patients with HB had received constitutional APC testing. Four (14%) were found to have APC pathogenic truncations of the APC protein and in addition two (7%) had APC missense variants of unknown clinical significance. Two patients (7%) had family histories indicative of familial adenomatous polyposis (FAP). Response to chemotherapy tracked differently in APC pathogenic cases, with a slower imaging response despite an equivalent or slightly faster α-fetoprotein (AFP) response. The prevalence of pathogenic APC variants in apparently sporadic HB may be higher than previously detected. Differences in time to imaging response, despite similar AFP response, may impact surgical planning. All patients with HB warrant germline APC mutation testing for underlying FAP. © 2017 Wiley Periodicals, Inc.

  13. Mutational screening of CHX10, GDF6, OTX2, RAX and SOX2 genes in 50 unrelated microphthalmia-anophthalmia-coloboma (MAC) spectrum cases.

    Science.gov (United States)

    Gonzalez-Rodriguez, J; Pelcastre, E L; Tovilla-Canales, J L; Garcia-Ortiz, J E; Amato-Almanza, M; Villanueva-Mendoza, C; Espinosa-Mattar, Z; Zenteno, J C

    2010-08-01

    Microphthalmia-anophthalmia-coloboma (MAC) are congenital eye malformations causing a significant percentage of visually impairments in children. Although these anomalies can arise from prenatal exposure to teratogens, mutations in well-defined genes originate potentially heritable forms of MAC. Mutations in genes such as CHX10, GDF6, RAX, SOX2 and OTX2, among others, have been recognised in dominant or recessive MAC. SOX2 and OTX2 are the two most commonly mutated genes in monogenic MAC. However, as more numerous samples of MAC subjects would be analysed, a better estimation of the actual involvement of specific MAC-genes could be made. Here, a comprehensive mutational analysis of the CHX10, GDF6, RAX, SOX2 and OTX2 genes was performed in 50 MAC subjects. PCR amplification and direct automated DNA sequencing of all five genes in 50 unrelated subjects. Eight mutations (16% prevalence) were recognised, including four GDF6 mutations (one novel), two novel RAX mutations, one novel OTX2 mutation and one SOX2 mutation. Anophthalmia and nanophthalmia, not previously associated with GDF6 mutations, were observed in two subjects carrying defects in this gene, expanding the spectrum of GDF6-linked ocular anomalies. Our study underscores the importance of genotyping large groups of patients from distinct ethnic origins for improving the estimation of the global involvement of particular MAC-causing genes.

  14. APP Mutations in Cerebral Amyloid Angiopathy with or without Cortical Calcifications: Report of Three Families and a Literature Review.

    Science.gov (United States)

    Sellal, François; Wallon, David; Martinez-Almoyna, Laurent; Marelli, Cecilia; Dhar, Abhinav; Oesterlé, Héléne; Rovelet-Lecrux, Anne; Rousseau, Stéphane; Kourkoulis, Christina E; Rosand, Jon; DiPucchio, Zora Y; Frosch, Matthew; Gombert, Claudine; Audoin, Bertrand; Miné, Manuèle; Riant, Florence; Frebourg, Thierry; Hannequin, Didier; Campion, Dominique; Greenberg, Steven M; Tournier-Lasserve, Elisabeth; Nicolas, Gaël

    2017-01-01

    Specific APP mutations cause cerebral amyloid angiopathy (CAA) with or without Alzheimer's disease (AD). We aimed at reporting APP mutations associated with CAA, describe the clinical, cerebrospinal fluid AD biomarkers, and neuroimaging features, and compare them with the data from the literature. We performed a retrospective study in two French genetics laboratories by gathering all clinical and neuroimaging data from patients referred for a genetic diagnosis of CAA with an age of onset before 66 years and fulfilling the other Boston revised criteria. We studied the segregation of mutations in families and performed a comprehensive literature review of all cases reported with the same APP mutation. We screened APP in 61 unrelated French patients. Three mutations, located in the Aβ coding region, were detected in five patients from three families: p.Ala692Gly (Flemish), p.Glu693Lys (Italian), and p.Asp694Asn (Iowa). Patients exhibited CAA and progressive cognitive impairment associated with cortical calcifications in the Iowa and Italian mutation carriers, but not the patient carrying the Flemish mutation. This is the first evidence of cortical calcification in patients with an APP mutation other than the Iowa mutation. We discuss the radiological, cerebrospinal fluid, and clinical phenotype of patients carrying these mutations in the literature.

  15. Mutation induction by ion beams in plants

    Energy Technology Data Exchange (ETDEWEB)

    Tanaka, Atsushi [Japan Atomic Energy Research Inst., Takasaki, Gunma (Japan). Takasaki Radiation Chemistry Research Establishment

    2001-03-01

    The effect of ion beams such as C, He, and Ne ions was investigated on the mutation induction in plants with the expectation that ion beams of high linear energy transfer (LET) can frequently produce large DNA alternation such as inversion, translocation and large deletion rather than point mutation. Mutation frequency was investigated using Arabidopsis visible phenotype loci and was 8 to 33 fold higher for 220 MeV carbon ions than for electrons. Mutation spectrum was investigated on the flower color of chrysanthemum cv to find that flower mutants induced by ion beams show complex and stripe types rather than single color. Polymerase chain reaction analysis was performed to investigate DNA alteration of mutations. In conclusion, the characteristics of ion beams for the mutation induction are 1) high frequency, 2) broad mutation spectrum, and 3) novel mutants. (S. Ohno)

  16. Mutation induction by ion beams in plants

    International Nuclear Information System (INIS)

    Tanaka, Atsushi

    2001-01-01

    The effect of ion beams such as C, He, and Ne ions was investigated on the mutation induction in plants with the expectation that ion beams of high linear energy transfer (LET) can frequently produce large DNA alternation such as inversion, translocation and large deletion rather than point mutation. Mutation frequency was investigated using Arabidopsis visible phenotype loci and was 8 to 33 fold higher for 220 MeV carbon ions than for electrons. Mutation spectrum was investigated on the flower color of chrysanthemum cv to find that flower mutants induced by ion beams show complex and stripe types rather than single color. Polymerase chain reaction analysis was performed to investigate DNA alteration of mutations. In conclusion, the characteristics of ion beams for the mutation induction are 1) high frequency, 2) broad mutation spectrum, and 3) novel mutants. (S. Ohno)

  17. Arterial stiffness and cognitive impairment.

    Science.gov (United States)

    Li, Xiaoxuan; Lyu, Peiyuan; Ren, Yanyan; An, Jin; Dong, Yanhong

    2017-09-15

    Arterial stiffness is one of the earliest indicators of changes in vascular wall structure and function and may be assessed using various indicators, such as pulse-wave velocity (PWV), the cardio-ankle vascular index (CAVI), the ankle-brachial index (ABI), pulse pressure (PP), the augmentation index (AI), flow-mediated dilation (FMD), carotid intima media thickness (IMT) and arterial stiffness index-β. Arterial stiffness is generally considered an independent predictor of cardiovascular and cerebrovascular diseases. To date, a significant number of studies have focused on the relationship between arterial stiffness and cognitive impairment. To investigate the relationships between specific arterial stiffness parameters and cognitive impairment, elucidate the pathophysiological mechanisms underlying the relationship between arterial stiffness and cognitive impairment and determine how to interfere with arterial stiffness to prevent cognitive impairment, we searched PUBMED for studies regarding the relationship between arterial stiffness and cognitive impairment that were published from 2000 to 2017. We used the following key words in our search: "arterial stiffness and cognitive impairment" and "arterial stiffness and cognitive impairment mechanism". Studies involving human subjects older than 30years were included in the review, while irrelevant studies (i.e., studies involving subjects with comorbid kidney disease, diabetes and cardiac disease) were excluded from the review. We determined that arterial stiffness severity was positively correlated with cognitive impairment. Of the markers used to assess arterial stiffness, a higher PWV, CAVI, AI, IMT and index-β and a lower ABI and FMD were related to cognitive impairment. However, the relationship between PP and cognitive impairment remained controversial. The potential mechanisms linking arterial stiffness and cognitive impairment may be associated with arterial pulsatility, as greater arterial pulsatility

  18. Distinct Mechanisms of Pathogenic DJ-1 Mutations in Mitochondrial Quality Control

    Directory of Open Access Journals (Sweden)

    Daniela Strobbe

    2018-03-01

    Full Text Available The deglycase and chaperone protein DJ-1 is pivotal for cellular oxidative stress responses and mitochondrial quality control. Mutations in PARK7, encoding DJ-1, are associated with early-onset familial Parkinson’s disease and lead to pathological oxidative stress and/or disrupted protein degradation by the proteasome. The aim of this study was to gain insights into the pathogenic mechanisms of selected DJ-1 missense mutations, by characterizing protein–protein interactions, core parameters of mitochondrial function, quality control regulation via autophagy, and cellular death following dopamine accumulation. We report that the DJ-1M26I mutant influences DJ-1 interactions with SUMO-1, in turn enhancing removal of mitochondria and conferring increased cellular susceptibility to dopamine toxicity. By contrast, the DJ-1D149A mutant does not influence mitophagy, but instead impairs Ca2+ dynamics and free radical homeostasis by disrupting DJ-1 interactions with a mitochondrial accessory protein known as DJ-1-binding protein (DJBP/EFCAB6. Thus, individual DJ-1 mutations have different effects on mitochondrial function and quality control, implying mutation-specific pathomechanisms converging on impaired mitochondrial homeostasis.

  19. Mutation in GM2A Leads to a Progressive Chorea-Dementia Syndrome

    Directory of Open Access Journals (Sweden)

    Mustafa A. Salih

    2015-07-01

    Full Text Available Background: The etiology of many cases of childhood-onset chorea remains undetermined, although advances in genomics are revealing both new disease-associated genes and variant phenotypes associated with known genes. Methods: We report a Saudi family with a neurodegenerative course dominated by progressive chorea and dementia in whom we performed homozygosity mapping and whole exome sequencing. Results: We identified a homozygous missense mutation in GM2A within a prominent block of homozygosity. This mutation is predicted to impair protein function. Discussion: Although discovered more than two decades ago, to date, only five patients with this rare form of GM2 gangliosidosis have been reported. The phenotype of previously described GM2A patients has been typified by onset in infancy, profound hypotonia and impaired volitional movement, intractable seizures, hyperacusis, and a macular cherry red spot. Our findings expand the phenotypic spectrum of GM2A mutation-positive gangliosidosis to include generalized chorea without macular findings or hyperacusis and highlight how mutations in neurodegenerative disease genes may present in unexpected ways.

  20. Are c.436G>A mutations less severe forms of Lafora disease? A case report

    Directory of Open Access Journals (Sweden)

    Hélène-Marie Lanoiselée

    2014-01-01

    Full Text Available Lafora disease is a form of progressive myoclonic epilepsy with autosomal recessive transmission. Two genes have been identified so far: EPM2A and NHLRC1, and a third gene, concerning a pediatric onset subform, has been recently proposed. We report the case of a 23-year-old woman of Turkish origin with an unusual disease course. Clinical onset was at the age of 19 years with tonic–clonic seizures, followed by cognitive impairment; EEG was in favor of Lafora disease, and the mutation c.436G>A (a missense mutation substituting aspartic acid in asparagine in the NHLRC1 gene confirmed this diagnosis. After 5 years of evolution, the patient only has moderate cognitive impairment. Some NHLRC1 mutations, particularly c.436G>A, are associated with a slower clinical course, but there are conflicting data in the literature. This case strengthens the hypothesis that the c.436G>A mutation in the NHLRC1 gene leads to less severe phenotypes and late-onset disease.

  1. XPD Helicase Structures and Activities: Insights into the Cancer and Aging Phenotypes from XPD Mutations

    Energy Technology Data Exchange (ETDEWEB)

    Tainer, John; Fan, Li; Fuss, Jill O.; Cheng, Quen J.; Arvai, Andrew S.; Hammel, Michal; Roberts, Victoria A.; Cooper, Priscilla K.; Tainer, John A.

    2008-06-02

    Mutations in XPD helicase, required for nucleotide excision repair (NER) as part of the transcription/repair complex TFIIH, cause three distinct phenotypes: cancer-prone xeroderma pigmentosum (XP), or aging disorders Cockayne syndrome (CS), and trichothiodystrophy (TTD). To clarify molecular differences underlying these diseases, we determined crystal structures of the XPD catalytic core from Sulfolobus acidocaldarius and measured mutant enzyme activities. Substrate-binding grooves separate adjacent Rad51/RecA-like helicase domains (HD1, HD2) and an arch formed by 4FeS and Arch domains. XP mutations map along the HD1 ATP-binding edge and HD2 DNA-binding channel and impair helicase activity essential for NER. XP/CS mutations both impair helicase activity and likely affect HD2 functional movement. TTD mutants lose or retain helicase activity but map to sites in all four domains expected to cause framework defects impacting TFIIH integrity. These results provide a foundation for understanding disease consequences of mutations in XPD and related 4Fe-4S helicases including FancJ.

  2. XPD Helicase Structures And Activities: Insights Into the Cancer And Aging Phenotypes From XPD Mutations

    Energy Technology Data Exchange (ETDEWEB)

    Fan, L.; Fuss, J.O.; Cheng, Q.J.; Arvai, A.S.; Hammel, M.; Roberts, V.A.; Cooper, P.K.; Tainer, J.A.

    2009-05-18

    Mutations in XPD helicase, required for nucleotide excision repair (NER) as part of the transcription/repair complex TFIIH, cause three distinct phenotypes: cancer-prone xeroderma pigmentosum (XP), or aging disorders Cockayne syndrome (CS), and trichothiodystrophy (TTD). To clarify molecular differences underlying these diseases, we determined crystal structures of the XPD catalytic core from Sulfolobus acidocaldarius and measured mutant enzyme activities. Substrate-binding grooves separate adjacent Rad51/RecA-like helicase domains (HD1, HD2) and an arch formed by 4FeS and Arch domains. XP mutations map along the HD1 ATP-binding edge and HD2 DNA-binding channel and impair helicase activity essential for NER. XP/CS mutations both impair helicase activity and likely affect HD2 functional movement. TTD mutants lose or retain helicase activity but map to sites in all four domains expected to cause framework defects impacting TFIIH integrity. These results provide a foundation for understanding disease consequences of mutations in XPD and related 4Fe-4S helicases including FancJ.

  3. Extremely low penetrance of deafness associated with the mitochondrial 12S rRNA mutation in 16 Chinese families: Implication for early detection and prevention of deafness

    International Nuclear Information System (INIS)

    Dai Pu; Liu Xin; Han Dongyi; Qian Yaping; Huang Deliang; Yuan Huijun; Li Weiming; Yu Fei; Zhang Ruining; Lin Hongyan; He Yong; Yu Youjun; Sun Quanzhu; Qin Huaiyi; Li Ronghua; Zhang Xin; Kang Dongyang; Cao Juyang; Young Wieyen; Guan Minxin

    2006-01-01

    Mutations in mitochondrial DNA (mtDNA) have been found to be associated with sensorineural hearing loss. We report here the clinical, genetic, and molecular characterization of 16 Chinese pedigrees (a total of 246 matrilineal relatives) with aminoglycoside-induced impairment. Clinical evaluation revealed the variable phenotype of hearing impairment including audiometric configuration in these subjects, although these subjects share some common features: being bilateral and sensorineural hearing impairment. Strikingly, these Chinese pedigrees exhibited extremely low penetrance of hearing loss, ranging from 4% to 18%, with an average of 8%. In particular, nineteen of 246 matrilineal relatives in these pedigrees had aminoglycoside-induced hearing loss. Mutational analysis of the mtDNA in these pedigrees showed the presence of homoplasmic 12S rRNA A1555G mutation, which has been associated with hearing impairment in many families worldwide. The extremely low penetrance of hearing loss in these Chinese families carrying the A1555G mutation strongly supports the notion that the A1555G mutation itself is not sufficient to produce the clinical phenotype. Children carrying the A1555G mutation are susceptible to the exposure of aminoglycosides, thereby inducing or worsening hearing impairment, as in the case of these Chinese families. Using those genetic and molecular approaches, we are able to diagnose whether children carry the ototoxic mtDNA mutation. Therefore, these data have been providing valuable information and technology to predict which individuals are at risk for ototoxicity, to improve the safety of aminoglycoside therapy, and eventually to decrease the incidence of deafness

  4. Oncogene mutational profile in nasopharyngeal carcinoma

    Directory of Open Access Journals (Sweden)

    Zhang ZC

    2014-03-01

    Full Text Available Zi-Chen Zhang,1,* Sha Fu,1,* Fang Wang,1 Hai-Yun Wang,1 Yi-Xin Zeng,2 Jian-Yong Shao11Department of Molecular Diagnostics, 2Department of Experimental Research, Sun Yat-sen University Cancer Center, State Key Laboratory of Oncology in South China, Collaborative Innovation Center of Cancer Medicine, Guangzhou, People's Republic of China *These authors contributed equally to this work Abstract: Nasopharyngeal carcinoma (NPC is a common tumor in Southern China, but the oncogene mutational status of NPC patients has not been clarified. Using time-of-flight mass spectrometry, 238 mutation hotspots in 19 oncogenes were examined in 123 NPC patients. The relationships between mutational status and clinical data were assessed with a χ2 or Fisher's exact test. Survival analysis was performed using the Kaplan–Meier method with the log-rank test. In 123 patients, 21 (17.1% NPC tumors were positive for mutations in eight oncogenes: six patients had PIK3CA mutations (4.9%, five NRAS mutations (4.1%, four KIT mutations (3.3%, two PDGFRA mutations (1.6%, two ABL mutations (1.6%, and one with simultaneous mutations in HRAS, EGFR, and BRAF (1%. Patients with mutations were more likely to relapse or develop metastasis than those with wild-type alleles (P=0.019. No differences or correlations were found in other clinical characteristics or in patient survival. No mutations were detected in oncogenes AKT1, AKT2, CDK, ERBB2, FGFR1, FGFR3, FLT3, JAK2, KRAS, MET, and RET. These results demonstrate an association between NPC and mutations in NRAS, KIT, PIK3CA, PDGFRA, and ABL, which are associated with patient relapse and metastasis. Keywords: NPC, oncogene, mutation

  5. Mutations in the satellite cell gene MEGF10 cause a recessive congenital myopathy with minicores.

    Science.gov (United States)

    Boyden, Steven E; Mahoney, Lane J; Kawahara, Genri; Myers, Jennifer A; Mitsuhashi, Satomi; Estrella, Elicia A; Duncan, Anna R; Dey, Friederike; DeChene, Elizabeth T; Blasko-Goehringer, Jessica M; Bönnemann, Carsten G; Darras, Basil T; Mendell, Jerry R; Lidov, Hart G W; Nishino, Ichizo; Beggs, Alan H; Kunkel, Louis M; Kang, Peter B

    2012-05-01

    We ascertained a nuclear family in which three of four siblings were affected with an unclassified autosomal recessive myopathy characterized by severe weakness, respiratory impairment, scoliosis, joint contractures, and an unusual combination of dystrophic and myopathic features on muscle biopsy. Whole genome sequence from one affected subject was filtered using linkage data and variant databases. A single gene, MEGF10, contained nonsynonymous mutations that co-segregated with the phenotype. Affected subjects were compound heterozygous for missense mutations c.976T > C (p.C326R) and c.2320T > C (p.C774R). Screening the MEGF10 open reading frame in 190 patients with genetically unexplained myopathies revealed a heterozygous mutation, c.211C > T (p.R71W), in one additional subject with a similar clinical and histological presentation as the discovery family. All three mutations were absent from at least 645 genotyped unaffected control subjects. MEGF10 contains 17 atypical epidermal growth factor-like domains, each of which contains eight cysteine residues that likely form disulfide bonds. Both the p.C326R and p.C774R mutations alter one of these residues, which are completely conserved in vertebrates. Previous work showed that murine Megf10 is required for preserving the undifferentiated, proliferative potential of satellite cells, myogenic precursors that regenerate skeletal muscle in response to injury or disease. Here, knockdown of megf10 in zebrafish by four different morpholinos resulted in abnormal phenotypes including unhatched eggs, curved tails, impaired motility, and disorganized muscle tissue, corroborating the pathogenicity of the human mutations. Our data establish the importance of MEGF10 in human skeletal muscle and suggest satellite cell dysfunction as a novel myopathic mechanism.

  6. Novel C16orf57 mutations in patients with Poikiloderma with Neutropenia: bioinformatic analysis of the protein and predicted effects of all reported mutations

    Directory of Open Access Journals (Sweden)

    Colombo Elisa A

    2012-01-01

    Full Text Available Abstract Background Poikiloderma with Neutropenia (PN is a rare autosomal recessive genodermatosis caused by C16orf57 mutations. To date 17 mutations have been identified in 31 PN patients. Results We characterize six PN patients expanding the clinical phenotype of the syndrome and the mutational repertoire of the gene. We detect the two novel C16orf57 mutations, c.232C>T and c.265+2T>G, as well as the already reported c.179delC, c.531delA and c.693+1G>T mutations. cDNA analysis evidences the presence of aberrant transcripts, and bioinformatic prediction of C16orf57 protein structure gauges the mutations effects on the folded protein chain. Computational analysis of the C16orf57 protein shows two conserved H-X-S/T-X tetrapeptide motifs marking the active site of a two-fold pseudosymmetric structure recalling the 2H phosphoesterase superfamily. Based on this model C16orf57 is likely a 2H-active site enzyme functioning in RNA processing, as a presumptive RNA ligase. According to bioinformatic prediction, all known C16orf57 mutations, including the novel mutations herein described, impair the protein structure by either removing one or both tetrapeptide motifs or by destroying the symmetry of the native folding. Finally, we analyse the geographical distribution of the recurrent mutations that depicts clusters featuring a founder effect. Conclusions In cohorts of patients clinically affected by genodermatoses with overlapping symptoms, the molecular screening of C16orf57 gene seems the proper way to address the correct diagnosis of PN, enabling the syndrome-specific oncosurveillance. The bioinformatic prediction of the C16orf57 protein structure denotes a very basic enzymatic function consistent with a housekeeping function. Detection of aberrant transcripts, also in cells from PN patients carrying early truncated mutations, suggests they might be translatable. Tissue-specific sensitivity to the lack of functionally correct protein accounts for the

  7. Patterns of Semantic Memory Impairment in Mild Cognitive Impairment

    Directory of Open Access Journals (Sweden)

    Sven Joubert

    2008-01-01

    Full Text Available Although the semantic memory impairment has been largely documented in Alzheimer's disease, little is known about semantic memory in the preclinical phase of the disease (Mild Cognitive Impairment. The purpose of this study was to document the nature of semantic breakdown using a battery of tests assessing different aspects of conceptual knowledge: knowledge about common objects, famous people and famous public events. Results indicate that all domains of semantic memory were impaired in MCI individuals but knowledge about famous people and famous events was affected to a greater extent than knowledge about objects. This pattern of results suggests that conceptual entities with distinctive and unique properties may be more prone to semantic breakdown in MCI. In summary, results of this study support the view that genuine semantic deficits are present in MCI. It could be useful to investigate the etiological outcome of patients failing or succeeding at such tests.

  8. Cognitive impairment and driving safety.

    Science.gov (United States)

    Eby, David W; Molnar, Lisa J

    2012-11-01

    As the populations of many countries continue to age, cognitive impairment will likely become more common. Individuals with cognitive impairment pose special challenges for families, health professionals, driving safety professionals, and the larger community, particularly if these older adults depend on driving as their primary means of community mobility. It is vital that we continue to extend our knowledge about the driving behavior of individuals' with cognitive impairment, as well as try to develop effective means of screening and assessing these individuals for fitness to drive and help facilitate their transition to non-driving when appropriate. This special issue is intended to provide researchers and practitioners an opportunity to present the most recent research findings on driving-related issues among older adults with cognitive impairment. The issue contains 11 original contributions from seven countries. The topics covered by these papers are: crash risks; screening, assessment, and fitness to drive; driving performance using a driving simulator; and driving behaviors and driving-related decisions of people with cognitive impairments. Copyright © 2012. Published by Elsevier Ltd.

  9. Mutations in the VNTR of the carboxyl-ester lipase gene (CEL) are a rare cause of monogenic diabetes

    DEFF Research Database (Denmark)

    Torsvik, Janniche; Johansson, Stefan; Johansen, Anders

    2009-01-01

    of the VNTR, and determined the VNTR-length of each allele. When blindly testing 56 members of the two families with known single-base deletions in the CEL VNTR, the method correctly assessed the mutation carriers. Screening of 241 probands from suspected maturity-onset diabetes of the young (MODY) families...... negative for mutations in known MODY genes (95 individuals from Denmark and 146 individuals from UK) revealed no deletions in the proximal repeats of the CEL VNTR. However, we found one Danish patient with a short, novel CEL allele containing only three VNTR repeats (normal range 7-23 in healthy controls......). This allele co-segregated with diabetes or impaired glucose tolerance in the patient's family as six of seven mutation carriers were affected. We also identified individuals who had three copies of a complete CEL VNTR. In conclusion, the CEL gene is highly polymorphic, but mutations in CEL are likely...

  10. Characterization of a mutation commonly associated with persistent stuttering: evidence for a founder mutation

    Science.gov (United States)

    Fedyna, Alison; Drayna, Dennis; Kang, Changsoo

    2010-01-01

    Stuttering is a disorder which affects the fluency of speech. It has been shown to have high heritability, and has recently been linked to mutations in the GNPTAB gene. One such mutation, Glu1200Lys, has been repeatedly observed in unrelated families and individual cases. Eight unrelated individuals carrying this mutation were analyzed in an effort to distinguish whether these arise from repeated mutation at the same site, or whether they represent a founder mutation with a single origin. Results show that all 12 chromosomes carrying this mutation share a common haplotype in this region, indicating it is a founder mutation. Further analysis estimated the age of this allele to be ~572 generations. Construction of a cladogram tracing the mutation through our study sample also supports the founder mutation hypothesis. PMID:20944643

  11. Predictable Phenotypes of Antibiotic Resistance Mutations.

    Science.gov (United States)

    Knopp, M; Andersson, D I

    2018-05-15

    Antibiotic-resistant bacteria represent a major threat to our ability to treat bacterial infections. Two factors that determine the evolutionary success of antibiotic resistance mutations are their impact on resistance level and the fitness cost. Recent studies suggest that resistance mutations commonly show epistatic interactions, which would complicate predictions of their stability in bacterial populations. We analyzed 13 different chromosomal resistance mutations and 10 host strains of Salmonella enterica and Escherichia coli to address two main questions. (i) Are there epistatic interactions between different chromosomal resistance mutations? (ii) How does the strain background and genetic distance influence the effect of chromosomal resistance mutations on resistance and fitness? Our results show that the effects of combined resistance mutations on resistance and fitness are largely predictable and that epistasis remains rare even when up to four mutations were combined. Furthermore, a majority of the mutations, especially target alteration mutations, demonstrate strain-independent phenotypes across different species. This study extends our understanding of epistasis among resistance mutations and shows that interactions between different resistance mutations are often predictable from the characteristics of the individual mutations. IMPORTANCE The spread of antibiotic-resistant bacteria imposes an urgent threat to public health. The ability to forecast the evolutionary success of resistant mutants would help to combat dissemination of antibiotic resistance. Previous studies have shown that the phenotypic effects (fitness and resistance level) of resistance mutations can vary substantially depending on the genetic context in which they occur. We conducted a broad screen using many different resistance mutations and host strains to identify potential epistatic interactions between various types of resistance mutations and to determine the effect of strain

  12. MPL mutation profile in JAK2 mutation-negative patients with myeloproliferative disorders.

    Science.gov (United States)

    Ma, Wanlong; Zhang, Xi; Wang, Xiuqiang; Zhang, Zhong; Yeh, Chen-Hsiung; Uyeji, Jennifer; Albitar, Maher

    2011-03-01

    Mutations in the thrombopoietin receptor gene (myeloproliferative leukemia, MPL) have been reported in patients with JAK2 V617F-negative chronic myeloproliferative disorders (MPDs). We evaluated the prevalence of MPL mutations relative to JAK2 mutations in patients with suspected MPDs. A total of 2790 patient samples submitted for JAK2 mutation analysis were tested using real-time polymerase chain reaction and bidirectional sequencing of plasma RNA. JAK2 V617F-negative samples were tested for JAK2 exons 12 to 14 mutations, and those with negative results were then tested for mutations in MPL exons 10 and 11. Of the 2790 patients, 529 (18.96%) had V617F, 12 (0.43%) had small insertions or deletions in exon 12, and 7 (0.25%) had other JAK2 mutations in exons 12 to 14. Of the 2242 JAK2 mutation-negative patients, 68 (3.03%) had MPL mutations. W515L was the predominant MPL mutation (n=46; 68%), and 10 (15%) patients had other W515 variants. The remaining MPL mutations (n=12, 17%) were detected at other locations in exons 10 and 11 and included 3 insertion/deletion mutations. The S505N mutation, associated with familial MPD, was detected in 3 patients. Overall, for every 100 V617F mutations in patients with suspected MPDs, there were 12.9 MPL mutations, 2.3 JAK2 exon 12 mutations, and 1.3 JAK2 exons 13 to 14 mutations. These findings suggest that MPL mutation screening should be performed before JAK2 exons 12 to 14 testing in JAK2 V617F-negative patients with suspected MPDs.

  13. Calreticulin Mutations in Bulgarian MPN Patients.

    Science.gov (United States)

    Pavlov, Ivan; Hadjiev, Evgueniy; Alaikov, Tzvetan; Spassova, Sylva; Stoimenov, Angel; Naumova, Elissaveta; Shivarov, Velizar; Ivanova, Milena

    2018-01-01

    Somatic mutations in JAK2, MPL and CALR are recurrently identified in most of the cases with Philadelphia chromosome negative myeloproliferative neoplasms (MPNs). We applied four molecular genetic methods for identification of CALR exon 9 mutations, including high resolution melt (HRM) analysis, Sanger sequencing, semiconductor target genes sequencing and whole exome sequencing. A total of 78 patients with myeloid malignancies were included in the study. We identified 14 CALR exon 9 mutated cases out of 78 studied patients with myeloid malignancies. All mutated patients were diagnosed with MPN being either PMF (n = 7) or ET (n = 7). Nine cases had type 1 mutations and 5 cases had type 2 mutations. CALR exon 9, MPL exon 10 and JAK2 p. V617F were mutually exclusive. There were no statistically significant differences in the hematological parameters between the cases with CALR and JAK2 or MPL mutations. Notably, all four techniques were fully concordant in the detection of CALR mutations. This is one of the few reports on the CALR mutations frequency in South-eastern populations. Our study shows that the frequency and patterns of these mutations is identical to those in the patients' cohorts from Western countries. Besides we demonstrated the utility of four different methods for their detection.

  14. [Behavioral impairments in Parkinson's disease].

    Science.gov (United States)

    Kashihara, Kenichi

    2004-09-01

    Behavioral impairments in parkinsonian patients include agitation, hypersexuality, stereotypic movement, pathological gambling, abuse of antiparkinsonian drugs, REM sleep behavioral disorder, and restless legs syndrome. Dementia, psychoses, and emotional disorders, such as depression and anxiety/panic disorder, also impair behavior. Symptoms may be produced by dysfunction of the central nervous system, medication, and/or the psychosocial problems associated with Parkinson's disease. Treatment therefore should be based on the cause of the symptoms seen. In some cases, the reduction or change of antiparkinsonian drugs, or both, may be effective. Treatment of the motor symptoms of Parkinson's disease, including motor fluctuations, may reduce the risk of panic attacks being evoked in the 'off' period. Use of antidepressants, sedatives, and neuroleptics may often be effective. Physicians should identify the causes of the symptoms of behavioral impairment and select appropriate treatments.

  15. Language Impairment and Generative Analysis

    Directory of Open Access Journals (Sweden)

    Andrej Stopar

    2004-12-01

    Full Text Available This article deals with different types of language impairment from the perspective of generative grammar. The paper focuses on syntactic deficiencies observed in aphasic and SLI (specific language impairment patients. We show that the observed ungrammatical structures do not appear in a random fashion but can be predicted by that theory of universal sentence structure which posits a strict hierarchy of its constituent parts. The article shows that while the hierarchically lower elements remain unaffected, the higher positions in the hierarchy show various degrees of syntactic impairment. The paper supports the implementation of recent developments in the field of generative grammar with the intention of encouraging further theoretical, experimental and therapeutic research in the field.

  16. The impairment of MAGMAS function in human is responsible for a severe skeletal dysplasia.

    Directory of Open Access Journals (Sweden)

    Cybel Mehawej

    2014-05-01

    Full Text Available Impairment of the tightly regulated ossification process leads to a wide range of skeletal dysplasias and deciphering their molecular bases has contributed to the understanding of this complex process. Here, we report a homozygous mutation in the mitochondria-associated granulocyte macrophage colony stimulating factor-signaling gene (MAGMAS in a novel and severe spondylodysplastic dysplasia. MAGMAS, also referred to as PAM16 (presequence translocase-associated motor 16, is a mitochondria-associated protein involved in preprotein translocation into the matrix. We show that MAGMAS is specifically expressed in trabecular bone and cartilage at early developmental stages and that the mutation leads to an instability of the protein. We further demonstrate that the mutation described here confers to yeast strains a temperature-sensitive phenotype, impairs the import of mitochondrial matrix pre-proteins and induces cell death. The finding of deleterious MAGMAS mutations in an early lethal skeletal dysplasia supports a key role for this mitochondrial protein in the ossification process.

  17. Mutation Spectrum and Phenotypic Features in Noonan Syndrome with PTPN11 Mutations: Definition of Two Novel Mutations.

    Science.gov (United States)

    Atik, Tahir; Aykut, Ayca; Hazan, Filiz; Onay, Huseyin; Goksen, Damla; Darcan, Sukran; Tukun, Ajlan; Ozkinay, Ferda

    2016-06-01

    To evaluate the spectrum of PTPN11 gene mutations in Noonan syndrome patients and to study the genotype-phenotype associations. In this study, twenty Noonan syndrome patients with PTPN11 mutations were included. The patients underwent a detailed clinical and physical evaluation. To identify inherited cases, parents of all mutation positive patients were analyzed. Thirteen different PTPN11 mutations, two of them being novel, were detected in the study group. These mutations included eleven missense mutations: p.G60A, p.D61N, p.Y62D, p.Y63C, p.E69Q, p.Q79R, p.Y279C,p.N308D, p.N308S, p.M504V, p.Q510R and two novel missense mutations: p.I56V and p.I282M. The frequency of cardiac abnormalities and short stature were found to be 80 % and 80 %, respectively. Mental retardation was not observed in patients having exon 8 mutations. No significant correlations were detected between other phenotypic features and genotypes. By identifying genotype-phenotype correlations, this study provides information on phenotypes observed in NS patients with different PTPN11 mutations.

  18. Induced Mutations in Thai Rice

    International Nuclear Information System (INIS)

    Klakhaeng, Kanchana

    2014-01-01

    Rice is the primary source of food for more than half of the world's population. It benefits greatly from technological inputs in the area of breeding such as induced mutation. Induced mutation can produce mutants with significant improvement in plant type, maturity, yields and protein ratio when compared to the parent. These improved traits enable the mutants to fit into farming systems with either shorter or longer growing seasons. Three induced mutant rice varieties, including RD6, RD10 and RD15, are well accepted by farmers and consumers in Thailand. RD6 and RD15 were aromatic, photosensitive varieties which were derived from KDML105 by acute irradiation of 20 and 15 kilorad gamma ray, respectively. After induced mutation, pedigree selection was applied. RD6 showed drought tolerance and also good grain quality including softness and good aroma with a higher average yield than the famous glutinous variety, San-Pah-Tong. Additionally, it was resistant to blast and brown spot diseases with an average yield of 4.19 tons/ha. RD15 showed drought tolerance and resistance to brown spot disease with the highest yield of 3.5 tons/ha. These two mutant varieties are currently the most famous aromatic rice varieties in Thailand. On the other hand, RD10 is a glutinous, photoperiod insensitive rice variety which was derived from RD1 by irradiation of 1 kilorad fast neutrons. RD10 showed good grain quality such as softness and stickiness with the yield of 4.25 tons/ha. As an on-going project, recommended rice varieties were irradiated with electron beam for anaerobic germination ability, submergence tolerance, stagnant-flood tolerance and also internode elongation.

  19. Analysis of Y chromosome microdeletions and CFTR gene mutations as genetic markers of infertility in Serbian men

    Directory of Open Access Journals (Sweden)

    Dinić Jelena

    2007-01-01

    Full Text Available Background/Aim. Impaired fertility of a male partner is the main cause of infertility in up to one half of all infertile couples. At the genetic level, male infertility can be caused by chromosome aberrations or gene mutations. The presence and types of Y chromosome microdeletions and cystic fybrosis transmembrane conductance regulator (CFTR gene mutations as genetic cause of male infertility was tested in Serbian men. The aim of this study was to analyze CFTR gene mutations and Y chromosome microdelations as potential causes of male infertility in Serbian patients, as well as to test the hypothesis that CFTR mutations in infertile men are predominantly located in the several last exons of the gene. Methods. This study has encompassed 33 men with oligo- or azoospermia. The screening for Y chromosome microdeletions in the azoospermia factor (AZF region was performed by multiplex PCR analysis. The screening of the CFTR gene was performed by denaturing gradient gel electrophoresis (DGGE method. Results. Deletions on Y chromosome were detected in four patients, predominantly in AZFc region (four of total six deletions. Mutations in the CFTR gene were detected on eight out of 66 analyzed chromosomes of infertile men. The most common mutation was F508del (six of total eight mutations. Conclusion. This study confirmed that both Y chromosome microdeletions and CFTR gene mutations played important role in etiology of male infertility in Serbian infertile men. Genetic testing for Y chromosome microdeletions and CFTR gene mutations has been introduced in routine diagnostics and offered to couples undergoing assisted reproduction techniques. Considering that both the type of Y chromosome microdeletion and the type of CFTR mutation have a prognostic value, it is recommended that AZF and CFTR genotyping should not only be performed in patients with reduced sperm quality before undergoing assisted reproduction, but also for the purpose of preimplantation and

  20. Relationship between p53 dysfunction, CD38 expression, and IgV(H) mutation in chronic lymphocytic leukemia.

    Science.gov (United States)

    Lin, Ke; Sherrington, Paul D; Dennis, Michael; Matrai, Zoltan; Cawley, John C; Pettitt, Andrew R

    2002-08-15

    Established adverse prognostic factors in chronic lymphocytic leukemia (CLL) include CD38 expression, relative lack of IgV(H) mutation, and defects of the TP53 gene. However, disruption of the p53 pathway can occur through mechanisms other than TP53 mutation, and we have recently developed a simple screening test that detects p53 dysfunction due to mutation of the genes encoding either p53 or ATM, a kinase that regulates p53. The present study was conducted to examine the predictive value of this test and to establish the relationship between p53 dysfunction, CD38 expression, and IgV(H) mutation. CLL cells from 71 patients were examined for IgV(H) mutation, CD38 expression, and p53 dysfunction (detected as an impaired p53/p21 response to ionizing radiation). Survival data obtained from 69 patients were analyzed according to each of these parameters. Relative lack of IgV(H) mutation (less than 5%; n = 45), CD38 positivity (antigen expressed on more than 20% of malignant cells; n = 19), and p53 dysfunction (n = 19) were independently confirmed as adverse prognostic factors. Intriguingly, all p53-dysfunctional patients and all but one of the CD38(+) patients had less [corrected] than 5% IgV(H) mutation. Moreover, patients with p53 dysfunction and/or CD38 positivity (n = 31) accounted for the short survival of the less mutated group. These findings indicate that the poor outcome associated with having less than 5% IgV(H) mutation may be due to the overrepresentation of high-risk patients with p53 dysfunction and/or CD38 positivity within this group, and that CD38(-) patients with functionally intact p53 may have a prolonged survival regardless of the extent of IgV(H) mutation.

  1. Immunohistochemical loss of 5-hydroxymethylcytosine expression in acute myeloid leukaemia: relationship to somatic gene mutations affecting epigenetic pathways.

    Science.gov (United States)

    Magotra, Minoti; Sakhdari, Ali; Lee, Paul J; Tomaszewicz, Keith; Dresser, Karen; Hutchinson, Lloyd M; Woda, Bruce A; Chen, Benjamin J

    2016-12-01

    Genes affecting epigenetic pathways are frequently mutated in myeloid malignancies, including acute myeloid leukaemia (AML). The genes encoding TET2, IDH1 and IDH2 are among the most commonly mutated genes, and cause defective conversion of 5-methylcytosine into 5-hydroxymethylcytosine (5hmC), impairing demethylation of DNA, and presumably serving as driver mutations in leukaemogenesis. The aim of this study was to correlate 5hmC immunohistochemical loss with the mutation status of genes involved in epigenetic pathways in AML. Immunohistochemical staining with an anti-5hmC antibody was performed on 41 decalcified, formalin-fixed paraffin-embedded (FFPE) bone marrow biopsies from patients with AML. Archived DNA was subjected to next-generation sequencing for analysis of a panel of genes, including TET2, IDH1, IDH2, WT1 and DNMT3A. TET2, IDH1, IDH2, WT1 and DNMT3A mutations were found in 46% (19/41) of the cases. Ten of 15 cases (67%) with TET2, IDH1, IDH2 or WT1 mutations showed deficient 5hmC staining, whereas nine of 26 cases (35%) without a mutation in these genes showed loss of 5hmC. It is of note that all four cases with TET2 mutations showed deficient 5hmC staining. Overall, somatic mutations in TET2, IDH1, IDH2, WT1 and DNMT3A were common in our cohort of AML cases. Immunohistochemical staining for 5hmC was lost in the majority of cases harbouring mutations in these genes, reflecting the proposed relationship between dysfunctional epigenetic pathways and leukaemogenesis. © 2016 John Wiley & Sons Ltd.

  2. Induced mutations for crop improvement

    International Nuclear Information System (INIS)

    Micke, A.; Donini, B.; Maluszynski, M.

    1990-01-01

    Mutation induction has become an established tool in plant breeding to supplement existing germ plasma and to improve cultivars in certain specific traits. Hundreds of improved varieties have been released to farmers for many different crop species, demonstrating the economic value of the technology. Limitations arise mainly from the large mutagenized populations to be screened and from the unsatisfactory selection methods. Both limitations may be eased to some extent by advances in techniques of plant in-vitro culture. (author). Refs, 1 fig., 7 tabs

  3. EGFR mutation frequency and effectiveness of erlotinib

    DEFF Research Database (Denmark)

    Weber, Britta; Hager, Henrik; Sorensen, Boe S

    2014-01-01

    mutation (S768I), and two complex mutations. Seven percent of the patients were never smokers. The differences in median progression-free survival and overall survival between the mutated group and the wild-type group were 8.0 vs. 2.5 months, p...-1 vs. 2-3) and line of treatment (1st vs. 2nd and 3rd) had no influence on outcome in EGFR-mutated patients. CONCLUSION: We found a higher frequency of EGFR mutations than expected in a cohort with less than 10% never smokers. The outcome after treatment with erlotinib was much better in patients......OBJECTIVES: In 2008, we initiated a prospective study to explore the frequency and predictive value of epidermal growth factor receptor (EGFR) mutations in an unselected population of Danish patients with non-small cell lung cancer offered treatment with erlotinib, mainly in second-line. MATERIALS...

  4. Mutation, Witten index, and quiver invariant

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Heeyeon [Perimeter Institute for Theoretical Physics,31 Caroline Street North, Waterloo, N2L 2Y5, Ontario (Canada); Lee, Seung-Joo [Department of Physics, Robeson Hall, Virginia Tech,Blacksburg, VA 24061 (United States); Yi, Piljin [School of Physics, Korea Institute for Advanced Study,Seoul 130-722 (Korea, Republic of)

    2015-07-20

    We explore Seiberg-like dualities, or mutations, for N=4 quiver quantum mechanics in the context of wall-crossing. In contrast to higher dimensions, the 1d Seiberg-duality must be performed with much care. With fixed Fayet-Iliopoulos constants, at most two nodes can be mutated, one left and the other right, mapping a chamber of a quiver into a chamber of a mutated quiver. We delineate this complex pattern for triangle quivers and show how the Witten indices are preserved under such finely chosen mutations. On the other hand, the quiver invariants, or wall-crossing-safe part of supersymmetric spectra, mutate more straightforwardly, whereby a quiver is mapped to a quiver. The mutation rule that preserves the quiver invariant is different from the usual one, however, which we explore and confirm numerically.

  5. Mutation, Witten index, and quiver invariant

    International Nuclear Information System (INIS)

    Kim, Heeyeon; Lee, Seung-Joo; Yi, Piljin

    2015-01-01

    We explore Seiberg-like dualities, or mutations, for N=4 quiver quantum mechanics in the context of wall-crossing. In contrast to higher dimensions, the 1d Seiberg-duality must be performed with much care. With fixed Fayet-Iliopoulos constants, at most two nodes can be mutated, one left and the other right, mapping a chamber of a quiver into a chamber of a mutated quiver. We delineate this complex pattern for triangle quivers and show how the Witten indices are preserved under such finely chosen mutations. On the other hand, the quiver invariants, or wall-crossing-safe part of supersymmetric spectra, mutate more straightforwardly, whereby a quiver is mapped to a quiver. The mutation rule that preserves the quiver invariant is different from the usual one, however, which we explore and confirm numerically.

  6. A NEW MUTATION OPERATOR IN GENETIC PROGRAMMING

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    Anuradha Purohit

    2013-01-01

    Full Text Available This paper proposes a new type of mutation operator, FEDS (Fitness, Elitism, Depth, and Size mutation in genetic programming. The concept behind the new mutation operator is inspired from already introduced FEDS crossover operator to handle the problem of code bloating. FEDS mutation operates by using local elitism replacement in combination with depth limit and size of the trees to reduce bloat with a subsequent improvement in the performance of trees (program structures. We have designed a multiclass classifier for some benchmark datasets to test the performance of proposed mutation. The results show that when the initial run uses FEDS crossover and the concluding run uses FEDS mutation, then not only is the final result significantly improved but there is reduction in bloat also.

  7. Dermal fibroblasts from patients with Parkinson’s disease have normal GCase activity and autophagy compared to patients with PD and GBA mutations [version 2; referees: 2 approved

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    Lucy M Collins

    2018-02-01

    Full Text Available Background: Recently, the development of Parkinson’s disease (PD has been linked to a number of genetic risk factors, of which the most common is glucocerebrosidase (GBA mutations. Methods: We investigated PD and Gaucher Disease (GD patient derived skin fibroblasts using biochemistry assays. Results: PD patient derived skin fibroblasts have normal glucocerebrosidase (GCase activity, whilst patients with PD and GBA mutations have a selective deficit in GCase enzyme activity and impaired autophagic flux. Conclusions: This data suggests that only PD patients with a GBA mutation have altered GCase activity and autophagy, which may explain their more rapid clinical progression.

  8. Frontotemporal lobar degeneration: old knowledge and new insight into the pathogenetic mechanisms of tau mutations

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    Giacomina eRossi

    2015-10-01

    Full Text Available Frontotemporal lobar degeneration is a group of heterogeneous neurodegenerative diseases which includes tauopathies. In the central nervous system tau is the major microtubule-associated protein of neurons, promoting assembly and stabilization of microtubules required for morphogenesis and axonal transport. Primary tauopathies are characterized by deposition of abnormal fibrils of tau in neuronal and glial cells, leading to neuronal death, brain atrophy and eventually dementia.In genetic tauopathies mutations of tau gene impair the ability of tau to bind to microtubules, alter the normal ratio among tau isoforms and favour fibril formation.Recently, additional functions have been ascribed to tau and different pathogenetic mechanisms are then emerging. In fact, a role of tau in DNA protection and genome stability has been reported and chromosome aberrations have been found associated with tau mutations. Furthermore, newly structurally and functionally characterized mutations have suggested novel pathological features, such as a tendency to form oligomeric rather than fibrillar aggregates. Tau mutations affecting axonal transport and plasma membrane interaction have also been described.In this paper, we will review the pathogenetic mechanisms underlying tau mutations, focusing in particular on the less common aspects, so far poorly investigated.

  9. A homozygous missense mutation in human KLOTHO causes severe tumoral calcinosis

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    Ichikawa, Shoji; Imel, Erik A.; Kreiter, Mary L.; Yu, Xijie; Mackenzie, Donald S.; Sorenson, Andrea H.; Goetz, Regina; Mohammadi, Moosa; White, Kenneth E.; Econs, Michael J.

    2007-01-01

    Familial tumoral calcinosis is characterized by ectopic calcifications and hyperphosphatemia due to inactivating mutations in FGF23 or UDP-N-acetyl-α-D-galactosamine:polypeptide N-acetylgalactosaminyltransferase 3 (GALNT3). Herein we report a homozygous missense mutation (H193R) in the KLOTHO (KL) gene of a 13-year-old girl who presented with severe tumoral calcinosis with dural and carotid artery calcifications. This patient exhibited defects in mineral ion homeostasis with marked hyperphosphatemia and hypercalcemia as well as elevated serum levels of parathyroid hormone and FGF23. Mapping of H193R mutation onto the crystal structure of myrosinase, a plant homolog of KL, revealed that this histidine residue was at the base of the deep catalytic cleft and mutation of this histidine to arginine should destabilize the putative glycosidase domain (KL1) of KL, thereby attenuating production of membrane-bound and secreted KL. Indeed, compared with wild-type KL, expression and secretion of H193R KL were markedly reduced in vitro, resulting in diminished ability of FGF23 to signal via its cognate FGF receptors. Taken together, our findings provide what we believe to be the first evidence that loss-of-function mutations in human KL impair FGF23 bioactivity, underscoring the essential role of KL in FGF23-mediated phosphate and vitamin D homeostasis in humans. PMID:17710231

  10. TUBB2B Mutation in an Adult Patient with Myoclonus-Dystonia

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    Joshua T. Geiger

    2017-08-01

    Full Text Available Background: Tubulin mutations are a cause of neuronal migrational disorders referred to as tubulinopathies. Mutations in tubulin genes can have a severe impact on microtubule function and result in heterogeneous clinical presentations. Current understanding of the clinical spectrum of tubulinopathies is predominantly based on research in fetal tissue and early-childhood cases. Methods: Testing of candidate genes followed by whole-exome sequencing was performed in an adult woman with a neurodevelopmental, hyperkinetic movement disorder, to identify the underlying genetic cause. Bioinformatic modeling and a systematic review of literature was conducted to investigate genotype-phenotype correlations. Results: The patient was found to carry a heterozygous, de novo c.722G>A, p.R241H mutation in a conserved domain of TUBB2B, encoding the β-isoform of tubulin. In silico analysis indicated that this mutation was pathogenic. On neuroimaging, the patient had asymmetric pachygyria and dysmorphic basal ganglia. Her neurological examination demonstrated mild cognitive impairment, myoclonus-dystonia, and skeletal anomalies. Conclusions: Here, we report the unique phenotype of an adult TUBB2B mutation carrier. This case illustrates a relatively mild phenotype compared to previously described fetal and early childhood cases. This highlights the importance of obtaining molecular genetic testing in individuals with a high probability of a genetic disease, including undiagnosed adult patients.

  11. BRF1 mutations alter RNA polymerase III–dependent transcription and cause neurodevelopmental anomalies

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    Hög, Friederike; Dentici, Maria Lisa; Tan, Perciliz L.; Sowada, Nadine; Medeira, Ana; Gueneau, Lucie; Thiele, Holger; Kousi, Maria; Lepri, Francesca; Wenzeck, Larissa; Blumenthal, Ian; Radicioni, Antonio; Schwarzenberg, Tito Livio; Mandriani, Barbara; Fischetto, Rita; Morris-Rosendahl, Deborah J.; Altmüller, Janine; Reymond, Alexandre; Nürnberg, Peter; Merla, Giuseppe; Dallapiccola, Bruno; Katsanis, Nicholas; Cramer, Patrick; Kubisch, Christian

    2015-01-01

    RNA polymerase III (Pol III) synthesizes tRNAs and other small noncoding RNAs to regulate protein synthesis. Dysregulation of Pol III transcription has been linked to cancer, and germline mutations in genes encoding Pol III subunits or tRNA processing factors cause neurogenetic disorders in humans, such as hypomyelinating leukodystrophies and pontocerebellar hypoplasia. Here we describe an autosomal recessive disorder characterized by cerebellar hypoplasia and intellectual disability, as well as facial dysmorphic features, short stature, microcephaly, and dental anomalies. Whole-exome sequencing revealed biallelic missense alterations of BRF1 in three families. In support of the pathogenic potential of the discovered alleles, suppression or CRISPR-mediated deletion of brf1 in zebrafish embryos recapitulated key neurodevelopmental phenotypes; in vivo complementation showed all four candidate mutations to be pathogenic in an apparent isoform-specific context. BRF1 associates with BDP1 and TBP to form the transcription factor IIIB (TFIIIB), which recruits Pol III to target genes. We show that disease-causing mutations reduce Brf1 occupancy at tRNA target genes in Saccharomyces cerevisiae and impair cell growth. Moreover, BRF1 mutations reduce Pol III–related transcription activity in vitro. Taken together, our data show that BRF1 mutations that reduce protein activity cause neurodevelopmental anomalies, suggesting that BRF1-mediated Pol III transcription is required for normal cerebellar and cognitive development. PMID:25561519

  12. X-linked primary immunodeficiency associated with hemizygous mutations in the moesin (MSN) gene.

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    Lagresle-Peyrou, Chantal; Luce, Sonia; Ouchani, Farid; Soheili, Tayebeh Shabi; Sadek, Hanem; Chouteau, Myriam; Durand, Amandine; Pic, Isabelle; Majewski, Jacek; Brouzes, Chantal; Lambert, Nathalie; Bohineust, Armelle; Verhoeyen, Els; Cosset, François-Loïc; Magerus-Chatinet, Aude; Rieux-Laucat, Frédéric; Gandemer, Virginie; Monnier, Delphine; Heijmans, Catherine; van Gijn, Marielle; Dalm, Virgil A; Mahlaoui, Nizar; Stephan, Jean-Louis; Picard, Capucine; Durandy, Anne; Kracker, Sven; Hivroz, Claire; Jabado, Nada; de Saint Basile, Geneviève; Fischer, Alain; Cavazzana, Marina; André-Schmutz, Isabelle

    2016-12-01

    We investigated 7 male patients (from 5 different families) presenting with profound lymphopenia, hypogammaglobulinemia, fluctuating monocytopenia and neutropenia, a poor immune response to vaccine antigens, and increased susceptibility to bacterial and varicella zoster virus infections. We sought to characterize the genetic defect involved in a new form of X-linked immunodeficiency. We performed genetic analyses and an exhaustive phenotypic and functional characterization of the lymphocyte compartment. We observed hemizygous mutations in the moesin (MSN) gene (located on the X chromosome and coding for MSN) in all 7 patients. Six of the latter had the same missense mutation, which led to an amino acid substitution (R171W) in the MSN four-point-one, ezrin, radixin, moesin domain. The seventh patient had a nonsense mutation leading to a premature stop codon mutation (R533X). The naive T-cell counts were particularly low for age, and most CD8 + T cells expressed the senescence marker CD57. This phenotype was associated with impaired T-cell proliferation, which was rescued by expression of wild-type MSN. MSN-deficient T cells also displayed poor chemokine receptor expression, increased adhesion molecule expression, and altered migration and adhesion capacities. Our observations establish a causal link between an ezrin-radixin-moesin protein mutation and a primary immunodeficiency that could be referred to as X-linked moesin-associated immunodeficiency. Copyright © 2016 American Academy of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

  13. Frequency of CNKSR2 mutation in the X-linked epilepsy-aphasia spectrum.

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    Damiano, John A; Burgess, Rosemary; Kivity, Sara; Lerman-Sagie, Tally; Afawi, Zaid; Scheffer, Ingrid E; Berkovic, Samuel F; Hildebrand, Michael S

    2017-03-01

    Synaptic proteins are critical to neuronal function in the brain, and their deficiency can lead to seizures and cognitive impairments. CNKSR2 (connector enhancer of KSR2) is a synaptic protein involved in Ras signaling-mediated neuronal proliferation, migration and differentiation. Mutations in the X-linked gene CNKSR2 have been described in patients with seizures and neurodevelopmental deficits, especially those affecting language. In this study, we sequenced 112 patients with phenotypes within the epilepsy-aphasia spectrum (EAS) to determine the frequency of CNKSR2 mutation within this complex set of disorders. We detected a novel nonsense mutation (c.2314 C>T; p.Arg712*) in one Ashkenazi Jewish family, the male proband of which had a severe epileptic encephalopathy with continuous spike-waves in sleep (ECSWS). His affected brother also had ECSWS with better outcome, whereas the sister had childhood epilepsy with centrotemporal spikes. This mutation segregated in the three affected siblings in an X-linked manner, inherited from their mother who had febrile seizures. Although the frequency of point mutation is low, CNKSR2 sequencing should be considered in families with suspected X-linked EAS because of the specific genetic counseling implications. Wiley Periodicals, Inc. © 2017 International League Against Epilepsy.

  14. A novel CDKL5 mutation in a Japanese patient with atypical Rett syndrome.

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    Christianto, Antonius; Katayama, Syouichi; Kameshita, Isamu; Inazu, Tetsuya

    2016-08-01

    Rett syndrome (RTT) is a severe X-linked dominant inheritance disorder with a wide spectrum of clinical manifestations. Mutations in Methyl CpG binding protein 2 (MECP2), Cyclin dependent kinase-like 5 (CDKL5) and Forkhead box G1 (FOXG1) have been associated with classic and/or variant RTT. This study was conducted to identify the responsible gene(s) in atypical RTT patient, and to examine the effect of the mutation on protein function. DNA sequence analysis showed a novel heterozygous mutation in CDKL5 identified as c.530A>G which resulted in an amino acid substitution at position 177, from tyrosine to cysteine. Genotyping analysis indicated that the mutation was not merely a single nucleotide polymorphism (SNP). We also revealed that patient's blood lymphocytes had random X-chromosome inactivation (XCI) pattern. Further examination by bioinformatics analysis demonstrated the mutation caused damage or deleterious in its protein. In addition, we demonstrated in vitro kinase assay of mutant protein showed impairment of its activity. Taken together, the results suggested the mutant CDKL5 was responsible for the disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  15. A novel D458V mutation in the SANS PDZ binding motif causes atypical Usher syndrome.

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    Kalay, E; de Brouwer, A P M; Caylan, R; Nabuurs, S B; Wollnik, B; Karaguzel, A; Heister, J G A M; Erdol, H; Cremers, F P M; Cremers, C W R J; Brunner, H G; Kremer, H

    2005-12-01

    Homozygosity mapping and linkage analysis in a Turkish family with autosomal recessive prelingual sensorineural hearing loss revealed a 15-cM critical region at 17q25.1-25.3 flanked by the polymorphic markers D17S1807 and D17S1806. The maximum two-point lod score was 4.07 at theta=0.0 for the marker D17S801. The linkage interval contains the Usher syndrome 1G gene (USH1G) that is mutated in patients with Usher syndrome (USH) type 1g and encodes the SANS protein. Mutation analysis of USH1G led to the identification of a homozygous missense mutation D458V at the -3 position of the PDZ binding motif of SANS. This mutation was also present homozygously in one out of 64 additional families from Turkey with autosomal recessive nonsyndromic hearing loss and heterozygously in one out of 498 control chromosomes. By molecular modeling, we provide evidence that this mutation impairs the interaction of SANS with harmonin. Ophthalmologic examination and vestibular evaluation of patients from both families revealed mild retinitis pigmentosa and normal vestibular function. These results suggest that these patients suffer from atypical USH.

  16. Further evidence for P59L mutation in GJA3 associated with autosomal dominant congenital cataract

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    Li Wang

    2016-01-01

    Full Text Available Context: Congenital cataracts are one of the common eye disorders leading to visual impairment or blindness in children worldwide. We found a Chinese family with autosomal dominant pulverulent cataract. Aims: To identify the pathogenic gene mutation in a Chinese family with autosomal dominant inherited pulverulent cataract. Subjects and Methods: After obtained informed consent, detailed ophthalmic examinations were carried out; genomic DNAs were obtained from seven family members in a three-generation Chinese family with three affected. All exons of candidate genes were amplified by polymerase chain reaction and were sequenced performed by bidirectional sequencing. Results: By sequencing the encoding regions of the candidate genes, a missense mutation (c. 176C>T was detected in gap junction protein alpha 3 genes (GJA3, which resulted in the substitution of highly conserved proline by leucine at codon 59 (p.P59L. The mutation co-segregated with all patients and was absent in 100 normal Chinese controls. Conclusions: The study identified a missense mutation (c. 176C>T in GJA3 gene associated with autosomal dominant congenital pulverulent cataract in a Chinese family. It gave further evidence of phenotype heterogeneity for P59L mutation in GJA3 associated with congenital cataract.

  17. Cataract as a phenotypic marker for a mutation in WFS1, the Wolfram syndrome gene.

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    Titah, Salah Mohamed Cherif; Meunier, Isabelle; Blanchet, Catherine; Lopez, Severine; Rondouin, Gerard; Lenaers, Guy; Amati-Bonneau, Patrizia; Reynier, Pascal; Paquis-Flucklinger, Veronique; Hamel, Christian P

    2012-01-01

    Wolfram syndrome (WS) or diabetes insipidus, diabetes mellitus, optic atrophy, and deafness (DIDMOAD) (OMIM 222300) is an inherited neurodegenerative disease characterized by diabetes mellitus and optic atrophy as the 2 major criteria, followed later in life by deafness, diabetes insipidus, and various signs of neurologic impairment. The presence of a cataract has been variably mentioned in WS. Two members of a family had thorough ophthalmic examination and their DNA was screened for mutations in mitochondrial DNA, WFS1, OPA1, and OPA3 genes. We report a patient who first had surgery for bilateral cataract at age 5 and who subsequently presented typical signs of WS, i.e., diabetes mellitus, optic atrophy with reduced visual acuity at 20/400 on both eyes at age 22, and mild deafness. The patient was found to be a compound heterozygote for 2 truncating mutations in WFS1, the major WS gene. She carried the previously reported c.1231_1233 delCT and a novel c.2431_2465dup35 mutation. She also was heterozygote for a novel OPA1 sequence variant, c.929A>G in exon 9, whose pathogenicity remains uncertain. The patient's mother was a heterozygous carrier of the c.2431_2465dup35 mutation. She did not have diabetes mellitus or optic atrophy but had bilateral polar cataract. She did not carry the OPA1 sequence variant. Cataract could be a marker for the WFS1 heterozygosity in this family, namely the c.2431_2465dup35 mutation.

  18. RAI1 gene mutations: mechanisms of Smith–Magenis Syndrome

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    Falco M

    2017-11-01

    Full Text Available Mariateresa Falco,1,* Sonia Amabile,1,* Fabio Acquaviva2 1Department of Molecular Medicine and Medical Biotechnology, University of Naples “Federico II”, Naples, Italy; 2Department of Translational Medical Sciences (DISMET, Section of Pediatric Clinical Genetics, University of Naples “Federico II”, Naples, Italy *These authors contributed equally to this work Abstract: Smith–Magenis syndrome (SMS; OMIM #182290 is a complex genetic disorder characterized by distinctive physical features, developmental delay, cognitive impairment, and a typical behavioral phenotype. SMS is caused by interstitial 17p11.2 deletions, encompassing multiple genes and including the retinoic acid-induced 1 gene (RAI1, or by mutations in RAI1 itself. About 10% of all the SMS patients, in fact, carry an RAI1 mutation responsible for the phenotype. RAI1 (OMIM *607642 is a dosage-sensitive gene expressed in many tissues and highly conserved among species. Over the years, several studies have demonstrated that RAI1 (or its homologs in animal models acts as a transcriptional factor implicated in embryonic neurodevelopment, neuronal differentiation, cell growth and cell cycle regulation, bone and skeletal development, lipid and glucose metabolisms, behavioral functions, and circadian activity. Patients with RAI1 pathogenic variants show some phenotypic differences when compared to those carrying the typical deletion. They usually have lower incidence of hypotonia and less cognitive impairment than those with 17p11.2 deletions but more frequently show the behavioral characteristics of the syndrome and overeating issues. These differences reflect the primary pathogenetic role of RAI1 without the pathogenetic contribution of the other genes included in the typical 17p11.2 deletion. The better comprehension of physiological roles of RAI1, its molecular co-workers and interactors, and its contribution in determining the typical SMS phenotype will certainly open a new path

  19. The Mutational Robustness of Influenza A Virus.

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    Elisa Visher

    2016-08-01

    Full Text Available A virus' mutational robustness is described in terms of the strength and distribution of the mutational fitness effects, or MFE. The distribution of MFE is central to many questions in evolutionary theory and is a key parameter in models of molecular evolution. Here we define the mutational fitness effects in influenza A virus by generating 128 viruses, each with a single nucleotide mutation. In contrast to mutational scanning approaches, this strategy allowed us to unambiguously assign fitness values to individual mutations. The presence of each desired mutation and the absence of additional mutations were verified by next generation sequencing of each stock. A mutation was considered lethal only after we failed to rescue virus in three independent transfections. We measured the fitness of each viable mutant relative to the wild type by quantitative RT-PCR following direct competition on A549 cells. We found that 31.6% of the mutations in the genome-wide dataset were lethal and that the lethal fraction did not differ appreciably between the HA- and NA-encoding segments and the rest of the genome. Of the viable mutants, the fitness mean and standard deviation were 0.80 and 0.22 in the genome-wide dataset and best modeled as a beta distribution. The fitness impact of mutation was marginally lower in the segments coding for HA and NA (0.88 ± 0.16 than in the other 6 segments (0.78 ± 0.24, and their respective beta distributions had slightly different shape parameters. The results for influenza A virus are remarkably similar to our own analysis of CirSeq-derived fitness values from poliovirus and previously published data from other small, single stranded DNA and RNA viruses. These data suggest that genome size, and not nucleic acid type or mode of replication, is the main determinant of viral mutational fitness effects.

  20. Two families with normosmic congenital hypogonadotropic hypogonadism and biallelic mutations in KISS1R (KISS1 receptor: clinical evaluation and molecular characterization of a novel mutation.

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    Frédéric Brioude

    Full Text Available CONTEXT: KISS1R mutations have been reported in few patients with normosmic congenital hypogonadotropic hypogonadism (nCHH (OMIM #146110. OBJECTIVE: To describe in detail nCHH patients with biallelic KISS1R mutations belonging to 2 unrelated families, and to functionally characterize a novel KISS1R mutation. RESULTS: An original mutant, p.Tyr313His, was found in the homozygous state in 3 affected kindred (2 females and 1 male from a consanguineous Portuguese family. This mutation, located in the seventh transmembrane domain, affects a highly conserved amino acid, perturbs the conformation of the transmembrane segment, and impairs MAP kinase signaling and intracellular calcium release. In the second family, a French Caucasian male patient with nCHH was found to carry two recurrent mutations in the compound heterozygous state (p.Leu102Pro/Stop399Arg. In this man, pulsatile GnRH (Gonadotropin Releasing Hormone administration restored pulsatile LH (Luteinizing Hormone secretion and testicular hormone secretion. Later, long-term combined gonadotropin therapy induced spermatogenesis, enabling 3 successive pregnancies that resulted in 2 miscarriages and the birth of a healthy boy. CONCLUSION: We show that a novel loss-of-function mutation (p.Tyr313His in the KISS1R gene can cause familial nCHH, revealing the crucial role of this amino acid in KISS1R function. The observed restoration of gonadotropin secretion by exogenous GnRH administration further supports, in humans, the hypothalamic origin of the gonadotropin deficiency in this genetic form of nCHH.