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Sample records for autosomal-recessive hypomaturation amelogenesis

  1. Mutations in the beta propeller WDR72 cause autosomal-recessive hypomaturation amelogenesis imperfecta.

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    El-Sayed, Walid; Parry, David A; Shore, Roger C; Ahmed, Mushtaq; Jafri, Hussain; Rashid, Yasmin; Al-Bahlani, Suhaila; Al Harasi, Sharifa; Kirkham, Jennifer; Inglehearn, Chris F; Mighell, Alan J

    2009-11-01

    Healthy dental enamel is the hardest and most highly mineralized human tissue. Though acellular, nonvital, and without capacity for turnover or repair, it can nevertheless last a lifetime. Amelogenesis imperfecta (AI) is a collective term for failure of normal enamel development, covering diverse clinical phenotypes that typically show Mendelian inheritance patterns. One subset, known as hypomaturation AI, is characterised by near-normal volumes of organic enamel matrix but with weak, creamy-brown opaque enamel that fails prematurely after tooth eruption. Mutations in genes critical to enamel matrix formation have been documented, but current understanding of other key events in enamel biomineralization is limited. We investigated autosomal-recessive hypomaturation AI in a consanguineous Pakistani family. A whole-genome SNP autozygosity screen identified a locus on chromosome 15q21.3. Sequencing candidate genes revealed a point mutation in the poorly characterized WDR72 gene. Screening of WDR72 in a panel of nine additional hypomaturation AI families revealed the same mutation in a second, apparently unrelated, Pakistani family and two further nonsense mutations in Omani families. Immunohistochemistry confirmed intracellular localization in maturation-stage ameloblasts. WDR72 function is unknown, but as a putative beta propeller is expected to be a scaffold for protein-protein interactions. The nearest homolog, WDR7, is involved in vesicle mobilization and Ca2+-dependent exocytosis at synapses. Vesicle trafficking is important in maturation-stage ameloblasts with respect to secretion into immature enamel and removal of cleaved enamel matrix proteins via endocytosis. This raises the intriguing possibility that WDR72 is critical to ameloblast vesicle turnover during enamel maturation.

  2. Hypomaturation amelogenesis imperfecta caused by a novel SLC24A4 mutation.

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    Herzog, Curtis R; Reid, Bryan M; Seymen, Figen; Koruyucu, Mine; Tuna, Elif Bahar; Simmer, James P; Hu, Jan C-C

    2015-02-01

    In this case report of autosomal recessive pigmented hypomaturation amelogenesis imperfecta (AI), we identify a novel homozygous missense mutation (g.165151 T>G; c.1317 T>G; p.Leu436 Arg) in SLC24A4, a gene encoding a potassium-dependent sodium-calcium exchanger that is critical for hardening dental enamel during tooth development.

  3. Hypomaturation Amelogenesis Imperfecta Caused By A Novel SLC24A4 Mutation

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    Herzog, Curtis R.; Reid, Bryan M.; Seymen, Figen; Koruyucu, Mine; Tuna, Elif Bahar; Simmer, James P.; Hu, Jan C-C.

    2014-01-01

    In this case report of autosomal recessive pigmented hypomaturation amelogenesis imperfecta (AI), we identify a novel homozygous missense mutation (g.165151T>G; c.1317T>G; p.Leu436Arg) in SLC24A4, a gene encoding a potassium-dependent sodium-calcium exchanger that is critical for hardening dental enamel during tooth development. PMID:25442250

  4. Exonal deletion of SLC24A4 causes hypomaturation amelogenesis imperfecta.

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    Seymen, F; Lee, K-E; Tran Le, C G; Yildirim, M; Gencay, K; Lee, Z H; Kim, J-W

    2014-04-01

    Amelogenesis imperfecta is a heterogeneous group of genetic conditions affecting enamel formation. Recently, mutations in solute carrier family 24 member 4 (SLC24A4) have been identified to cause autosomal recessive hypomaturation amelogenesis imperfecta. We recruited a consanguineous family with hypomaturation amelogenesis imperfecta with generalized brown discoloration. Sequencing of the candidate genes identified a 10-kb deletion, including exons 15, 16, and most of the last exon of the SLC24A4 gene. Interestingly, this deletion was caused by homologous recombination between two 354-bp-long homologous sequences located in intron 14 and the 3' UTR. This is the first report of exonal deletion in SLC24A4 providing confirmatory evidence that the function of SLC24A4 in calcium transport has a crucial role in the maturation stage of amelogenesis.

  5. ITGB6 loss-of-function mutations cause autosomal recessive amelogenesis imperfecta.

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    Wang, Shih-Kai; Choi, Murim; Richardson, Amelia S; Reid, Bryan M; Lin, Brent P; Wang, Susan J; Kim, Jung-Wook; Simmer, James P; Hu, Jan C-C

    2014-04-15

    Integrins are cell-surface adhesion receptors that bind to extracellular matrices (ECM) and mediate cell-ECM interactions. Some integrins are known to play critical roles in dental enamel formation. We recruited two Hispanic families with generalized hypoplastic amelogenesis imperfecta (AI). Analysis of whole-exome sequences identified three integrin beta 6 (ITGB6) mutations responsible for their enamel malformations. The female proband of Family 1 was a compound heterozygote with an ITGB6 transition mutation in Exon 4 (g.4545G > A c.427G > A p.Ala143Thr) and an ITGB6 transversion mutation in Exon 6 (g.27415T > A c.825T > A p.His275Gln). The male proband of Family 2 was homozygous for an ITGB6 transition mutation in Exon 11 (g.73664C > T c.1846C > T p.Arg616*) and hemizygous for a transition mutation in Exon 6 of Nance-Horan Syndrome (NHS Xp22.13; g.355444T > C c.1697T > C p.Met566Thr). These are the first disease-causing ITGB6 mutations to be reported. Immunohistochemistry of mouse mandibular incisors localized ITGB6 to the distal membrane of differentiating ameloblasts and pre-ameloblasts, and then ITGB6 appeared to be internalized by secretory stage ameloblasts. ITGB6 expression was strongest in the maturation stage and its localization was associated with ameloblast modulation. Our findings demonstrate that early and late amelogenesis depend upon cell-matrix interactions. Our approach (from knockout mouse phenotype to human disease) demonstrates the power of mouse reverse genetics in mutational analysis of human genetic disorders and attests to the need for a careful dental phenotyping in large-scale knockout mouse projects.

  6. Noninvasive esthetic treatment for hypomaturation amelogenesis imperfecta: a case report.

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    Nahsan, Flávia Pardo Salata; Silva, Luciana Mendonça da; Lima, Thiago Mendes de; Bertocco, Verônica Pereira de Lima; Chui, Fabíola Mendonça da Silva; Martins, Leandro de Moura

    2016-01-01

    Enamel alterations, such as amelogenesis imperfecta, can compromise the harmony of the smile and the patient's self-esteem and may cause tooth sensitivity. A simple and effective treatment approach uses the natural stratification of composite resins to mask deficient enamel formation and mimic the natural appearance of the substrate. The operative steps and principles for restorative success are described in this case report with 36-month follow-up.

  7. Mutations in CNNM4 Cause Jalili Syndrome, Consisting of Autosomal-Recessive Cone-Rod Dystrophy and Amelogenesis Imperfecta

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    Parry, David A.; Mighell, Alan J.; El-Sayed, Walid; Shore, Roger C.; Jalili, Ismail K.; Dollfus, Hélène; Bloch-Zupan, Agnes; Carlos, Roman; Carr, Ian M.; Downey, Louise M.; Blain, Katharine M.; Mansfield, David C.; Shahrabi, Mehdi; Heidari, Mansour; Aref, Parissa; Abbasi, Mohsen; Michaelides, Michel; Moore, Anthony T.; Kirkham, Jennifer; Inglehearn, Chris F.

    2009-01-01

    The combination of recessively inherited cone-rod dystrophy (CRD) and amelogenesis imperfecta (AI) was first reported by Jalili and Smith in 1988 in a family subsequently linked to a locus on chromosome 2q11, and it has since been reported in a second small family. We have identified five further ethnically diverse families cosegregating CRD and AI. Phenotypic characterization of teeth and visual function in the published and new families reveals a consistent syndrome in all seven families, and all link or are consistent with linkage to 2q11, confirming the existence of a genetically homogenous condition that we now propose to call Jalili syndrome. Using a positional-candidate approach, we have identified mutations in the CNNM4 gene, encoding a putative metal transporter, accounting for the condition in all seven families. Nine mutations are described in all, three missense, three terminations, two large deletions, and a single base insertion. We confirmed expression of Cnnm4 in the neural retina and in ameloblasts in the developing tooth, suggesting a hitherto unknown connection between tooth biomineralization and retinal function. The identification of CNNM4 as the causative gene for Jalili syndrome, characterized by syndromic CRD with AI, has the potential to provide new insights into the roles of metal transport in visual function and biomineralization. PMID:19200525

  8. [Autosomal recessive polycystic kidney].

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    Todorov, V; Penkova, S; Lalev, I

    1990-01-01

    A case of a 22 years old woman with autosomal-recessive form of kidney polycystosis is presented. The diagnosis was made in early childhood. A combination of renal anomaly and hepatic fibrosis with manifestations of portal hypertension was present. No deviations from the other internal organs were found. At the age of 12 she entered into the stage of chronic renal failure. The last five years she is on dialysis treatment. She had survived several acute bleedings from esophageal varices. The authors are of the opinion that the case is of interest since patients with autosomal-recessive renal polycystosis very rarely reach majority.

  9. Homozygous and compound heterozygous MMP20 mutations in amelogenesis imperfecta.

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    Gasse, B; Karayigit, E; Mathieu, E; Jung, S; Garret, A; Huckert, M; Morkmued, S; Schneider, C; Vidal, L; Hemmerlé, J; Sire, J-Y; Bloch-Zupan, A

    2013-07-01

    In this article, we focus on hypomaturation autosomal-recessive-type amelogenesis imperfecta (type IIA2) and describe 2 new causal Matrix metalloproteinase 20 (MMP20) mutations validated in two unrelated families: a missense mutation p.T130I at the expected homozygous state, and a compound heterozygous mutation having the same mutation combined with a nucleotide deletion, leading to a premature stop codon (p.N120fz*2). We characterized the enamel structure of the latter case using scanning electron microscopy analysis and microanalysis (Energy-dispersive X-ray Spectroscopy, EDX) and confirmed the hypomaturation-type amelogenesis imperfecta as identified in the clinical diagnosis. The mineralized content was slightly decreased, with magnesium substituting for calcium in the crystal structure. The anomalies affected enamel with minimal inter-rod enamel present and apatite crystals perpendicular to the enamel prisms, suggesting a possible new role for MMP20 in enamel formation.

  10. Autosomal recessive epidermolytic palmoplantar keratoderma.

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    Alsaleh, Q A; Teebi, A S

    1990-08-01

    Palmoplantar keratoderma (PPK) is a heterogeneous group of disorders. Epidermolytic PPK is a well delineated autosomal dominant entity, but no recessive form is known. Here we report two sons of phenotypically normal, consanguineous, Arab parents with features suggestive of PPK. They presented with patchy eczematous skin lesions followed by PPK and raised serum levels of IgE. Skin biopsy from the keratotic lesions showed the features of epidermolytic hyperkeratosis. Autosomal recessive inheritance is suggested and the differential diagnosis is discussed.

  11. Autosomal recessive hereditary auditory neuropathy

    Institute of Scientific and Technical Information of China (English)

    王秋菊; 顾瑞; 曹菊阳

    2003-01-01

    Objectives: Auditory neuropathy (AN) is a sensorineural hearing disorder characterized by absent or abnormal auditory brainstem responses (ABRs) and normal cochlear outer hair cell function as measured by otoacoustic emissions (OAEs). Many risk factors are thought to be involved in its etiology and pathophysiology. Three Chinese pedigrees with familial AN are presented herein to demonstrate involvement of genetic factors in AN etiology. Methods: Probands of the above - mentioned pedigrees, who had been diagnosed with AN, were evaluated and followed up in the Department of Otolaryngology Head and Neck Surgery, China PLA General Hospital. Their family members were studied and the pedigree diagrams were established. History of illness, physical examination,pure tone audiometry, acoustic reflex, ABRs and transient evoked and distortion- product otoacoustic emissions (TEOAEs and DPOAEs) were obtained from members of these families. DPOAE changes under the influence of contralateral sound stimuli were observed by presenting a set of continuous white noise to the non - recording ear to exam the function of auditory efferent system. Some subjects received vestibular caloric test, computed tomography (CT)scan of the temporal bone and electrocardiography (ECG) to exclude other possible neuropathy disorders. Results: In most affected subjects, hearing loss of various degrees and speech discrimination difficulties started at 10 to16 years of age. Their audiological evaluation showed absence of acoustic reflex and ABRs. As expected in AN, these subjects exhibited near normal cochlear outer hair cell function as shown in TEOAE & DPOAE recordings. Pure- tone audiometry revealed hearing loss ranging from mild to severe in these patients. Autosomal recessive inheritance patterns were observed in the three families. In Pedigree Ⅰ and Ⅱ, two affected brothers were found respectively, while in pedigree Ⅲ, 2 sisters were affected. All the patients were otherwise normal without

  12. Genetics Home Reference: autosomal recessive cerebellar ataxia type 1

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    ... Genetics Home Health Conditions ARCA1 autosomal recessive cerebellar ataxia type 1 Enable Javascript to view the expand/ ... Open All Close All Description Autosomal recessive cerebellar ataxia type 1 ( ARCA1 ) is a condition characterized by ...

  13. Nephrocalcinosis (Enamel Renal Syndrome) Caused by Autosomal Recessive FAM20A Mutations

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    Jaureguiberry, Graciana; De la Dure-Molla, Muriel; Parry, David; Quentric, Mickael; Himmerkus, Nina; Koike, Toshiyasu; Poulter, James; Klootwijk, Enriko; Robinette, Steven L.; Howie, Alexander J.; Patel, Vaksha; Figueres, Marie-Lucile; Stanescu, Horia C.; Issler, Naomi; Nicholson, Jeremy K.; Bockenhauer, Detlef; Laing, Christopher; Walsh, Stephen B.; McCredie, David A.; Povey, Sue; Asselin, Audrey; Picard, Arnaud; Coulomb, Aurore; Medlar, Alan J.; Bailleul-Forestier, Isabelle; Verloes, Alain; Le Caignec, Cedric; Roussey, Gwenaelle; Guiol, Julien; Isidor, Bertrand; Logan, Clare; Shore, Roger; Johnson, Colin; Inglehearn, Christopher; Al-Bahlani, Suhaila; Schmittbuhl, Matthieu; Clauss, François; Huckert, Mathilde; Laugel, Virginie; Ginglinger, Emmanuelle; Pajarola, Sandra; Spartà, Giuseppina; Bartholdi, Deborah; Rauch, Anita; Addor, Marie-Claude; Yamaguti, Paulo M.; Safatle, Heloisa P.; Acevedo, Ana Carolina; Martelli-Júnior, Hercílio; dos Santos Netos, Pedro E.; Coletta, Ricardo D.; Gruessel, Sandra; Sandmann, Carolin; Ruehmann, Denise; Langman, Craig B.; Scheinman, Steven J.; Ozdemir-Ozenen, Didem; Hart, Thomas C.; Hart, P. Suzanne; Neugebauer, Ute; Schlatter, Eberhard; Houillier, Pascal; Gahl, William A.; Vikkula, Miikka; Bloch-Zupan, Agnès; Bleich, Markus; Kitagawa, Hiroshi; Unwin, Robert J.; Mighell, Alan; Berdal, Ariane; Kleta, Robert

    2013-01-01

    Background/Aims Calcium homeostasis requires regulated cellular and interstitial systems interacting to modulate the activity and movement of this ion. Disruption of these systems in the kidney results in nephrocalcinosis and nephrolithiasis, important medical problems whose pathogenesis is incompletely understood. Methods We investigated 25 patients from 16 families with unexplained nephrocalcinosis and characteristic dental defects (amelogenesis imperfecta, gingival hyperplasia, impaired tooth eruption). To identify the causative gene, we performed genome-wide linkage analysis, exome capture, next-generation sequencing, and Sanger sequencing. Results All patients had bi-allelic FAM20A mutations segregating with the disease; 20 different mutations were identified. Conclusions This au-tosomal recessive disorder, also known as enamel renal syndrome, of FAM20A causes nephrocalcinosis and amelogenesis imperfecta. We speculate that all individuals with biallelic FAM20A mutations will eventually show nephrocalcinosis. PMID:23434854

  14. Autosomal recessive cerebellar ataxias : the current state of affairs

    NARCIS (Netherlands)

    Vermeer, S.; van de Warrenburg, B. P. C.; Willemsen, M. A. A. P.; Cluitmans, M.; Scheffer, H.; Kremer, B. P.; Knoers, N. V. A. M.

    2011-01-01

    Among the hereditary ataxias, autosomal recessive cerebellar ataxias (ARCAs) encompass a diverse group of rare neurodegenerative disorders in which a cerebellar syndrome is the key clinical feature. The clinical overlap between the different cerebellar ataxias, the occasional atypical phenotypes, an

  15. Autosomal Recessive Polycystic Kidney Disease: Antenatal Diagnosis and Histopathological Correlation

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    Dayananda Kumar Rajanna

    2013-01-01

    Full Text Available Autosomal recessive polycystic kidney disease (ARPKD is one of the most common inheritable disease manifesting in infancy and childhood with a frequency of 1:6,000 to 1:55,000 births. The patient in her second trimester presented with a history of amenorrhea. Ultrasound examination revealed bilateral, enlarged, hyperechogenic kidneys, placentomegaly, and severe oligohydramnios. The pregnancy was terminated. An autopsy was performed on the fetus. Both the kidneys were found to be enlarged and the cut surface showed numerous cysts. The liver sections showed changes due to fibrosis. The final diagnosis of autosomal recessive polycystic kidney disease was made based on these findings. In this article, we correlate the ante-natal ultrasound and histopathological findings in autosomal recessive polycystic kidney disease.

  16. Genetics Home Reference: autosomal recessive spastic ataxia of Charlevoix-Saguenay

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    ... Genetics Home Health Conditions ARSACS autosomal recessive spastic ataxia of Charlevoix-Saguenay Enable Javascript to view the ... Open All Close All Description Autosomal recessive spastic ataxia of Charlevoix-Saguenay , more commonly known as ARSACS , ...

  17. Gonadal mosaicism as a rare cause of autosomal recessive inheritance.

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    Anazi, S; Al-Sabban, E; Alkuraya, F S

    2014-03-01

    Autosomal recessive diseases are typically caused by the biparental inheritance of familial mutant alleles. Unusual mechanisms by which the recessiveness of a mutant allele is unmasked include uniparental isodisomy and the occurrence of a de novo chromosomal rearrangement that disrupts the other allele. Gonadal mosaicism is a condition in which a postfertilization mutation is confined to the gamete precursors and is not detected in somatic tissues. Gonadal mosaicism is known to give the impression of autosomal recessive inheritance when recurrence of an autosomal-dominant condition among offspring of phenotypically normal parents is observed. Here, we report an extremely rare event in which maternal gonadal mosaicism for a recessive mutation in COL4A4 caused the recurrence of Alport syndrome within a consanguineous family. Such rare occurrence should be taken into account when analyzing pedigrees both for clinical and research purposes.

  18. Amelogenesis imperfecta

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    Aldred Michael

    2007-04-01

    Full Text Available Abstract Amelogenesis imperfecta (AI represents a group of developmental conditions, genomic in origin, which affect the structure and clinical appearance of enamel of all or nearly all the teeth in a more or less equal manner, and which may be associated with morphologic or biochemical changes elsewhere in the body. The prevalence varies from 1:700 to 1:14,000, according to the populations studied. The enamel may be hypoplastic, hypomineralised or both and teeth affected may be discoloured, sensitive or prone to disintegration. AI exists in isolation or associated with other abnormalities in syndromes. It may show autosomal dominant, autosomal recessive, sex-linked and sporadic inheritance patterns. In families with an X-linked form it has been shown that the disorder may result from mutations in the amelogenin gene, AMELX. The enamelin gene, ENAM, is implicated in the pathogenesis of the dominant forms of AI. Autosomal recessive AI has been reported in families with known consanguinity. Diagnosis is based on the family history, pedigree plotting and meticulous clinical observation. Genetic diagnosis is presently only a research tool. The condition presents problems of socialisation, function and discomfort but may be managed by early vigorous intervention, both preventively and restoratively, with treatment continued throughout childhood and into adult life. In infancy, the primary dentition may be protected by the use of preformed metal crowns on posterior teeth. The longer-term care involves either crowns or, more frequently these days, adhesive, plastic restorations.

  19. Mutations of the tyrosinase gene produce autosomal recessive ocular albinism

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    King, R.A.; Summers, C.G.; Oetting, W.S. [Univ. of Minnesota, Minneapolis, MN (United States)] [and others

    1994-09-01

    Albinism has historically been divided into ocular (OA) and oculocutaneous (OCA) types based on the presence or absence of clinically apparent skin and hair involvement in an individual with the ocular features of albinism. The major genes for OCA include the tyrosinase gene in OCA1 and the P gene in OCA2. X-linked and autosomal recessive OA have been described and the responsible genes have not been identified. We now present six Caucasian individuals who have the phenotype of autosomal recessive OA but who have OCA1 as shown by the presence of mutations of the tyrosinase. They had white or very light hair and white skin at birth, and cutaneous pigment developed in the first decade of life. At ages ranging from 1.5-23 years, hair color was dark blond to light brown. The skin had generalized pigment and well developed tan was present on the exposed arm and face skin of four. Iris pigment was present and iris translucency varied. Molecular analysis of the tyrosinase gene, using PCR amplification and direct di-deoxy sequencing showed the following mutations: E398Z/E398Q, P406S/g346a, R402E/T373K, ?/D383N, and H211N/T373K. The homozygous individual was not from a known consanguineous mating. T373K is the most common tyrosinase gene mutation in our laboratory. Three of these mutations are associated with a total loss of tyrosinase activity (g346a splice-site, T373K, and D383N), while four are associated with residual enzyme activity (H211N, R402E, E398Q, and P406S). These studies show that mutations of the tyrosinase gene can produce the phenotype of autosomal recessive OA in an individual who has normal amounts of cutaneous pigment and the ability to tan after birth. This extends the phenotypic range of OCA1 to normal cutaneous pigment after early childhood, and suggest that mutations of the tyrosinase gene account for a significant number of individuals with autosomal recessive OA.

  20. Clinical and molecular analysis of the enamelin gene ENAM in Colombian families with autosomal dominant amelogenesis imperfecta

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    Sandra Gutiérrez

    2012-01-01

    Full Text Available In this study, we analyzed the phenotype, clinical characteristics and presence of mutations in the enamelin gene ENAM in five Colombian families with autosomal dominant amelogenesis imperfecta (ADAI. 22 individuals (15 affected and seven unaffected belonging to five Colombian families with ADAI and eight individuals (three affected and five unaffected belonging to three Colombian families with autosomal recessive amelogenesis imperfecta (ARAI that served as controls for molecular alterations and inheritance patterns were studied. Clinical, radiographic and genetic evaluations were done in all individuals. Eight exons and three intron-exon boundaries were sequenced for mutation analysis. Two of the five families with ADAI had the hypoplasic phenotype, two had the hypocalcified phenotype and one had the hypomaturative phenotype. Anterior open bite and mandibular retrognathism were the most frequent skeletal abnormalities in the families with ADAI. No mutations were found. These findings suggest that ADAI in these Colombian families was unrelated to previously described mutations in the ENAM gene. These results also indicate that other regions not included in this investigation, such as the promoter region, introns and other genes should be considered as potential ADAI candidates.

  1. Clinical and molecular analysis of the enamelin gene ENAM in Colombian families with autosomal dominant amelogenesis imperfecta.

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    Gutiérrez, Sandra; Torres, Diana; Briceño, Ignacio; Gómez, Ana Maria; Baquero, Eliana

    2012-07-01

    In this study, we analyzed the phenotype, clinical characteristics and presence of mutations in the enamelin gene ENAM in five Colombian families with autosomal dominant amelogenesis imperfecta (ADAI). 22 individuals (15 affected and seven unaffected) belonging to five Colombian families with ADAI and eight individuals (three affected and five unaffected) belonging to three Colombian families with autosomal recessive amelogenesis imperfecta (ARAI) that served as controls for molecular alterations and inheritance patterns were studied. Clinical, radiographic and genetic evaluations were done in all individuals. Eight exons and three intron-exon boundaries were sequenced for mutation analysis. Two of the five families with ADAI had the hypoplasic phenotype, two had the hypocalcified phenotype and one had the hypomaturative phenotype. Anterior open bite and mandibular retrognathism were the most frequent skeletal abnormalities in the families with ADAI. No mutations were found. These findings suggest that ADAI in these Colombian families was unrelated to previously described mutations in the ENAM gene. These results also indicate that other regions not included in this investigation, such as the promoter region, introns and other genes should be considered as potential ADAI candidates.

  2. Microcephaly-chorioretinopathy syndrome, autosomal recessive form. A case report

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    Rafael Fabiano Machado Rosa

    Full Text Available CONTEXT: The autosomal recessive form of microcephaly-chorioretinopathy syndrome is a rare genetic condition that is considered to be an important differential diagnosis with congenital toxoplasmosis.CASE REPORT: Our patient was a seven-year-old white boy who was initially diagnosed with congenital toxoplasmosis. However, his serological tests for congenital infections, including toxoplasmosis, were negative. He was the first child of young, healthy and consanguineous parents (fourth-degree relatives. The parents had normal head circumferences and intelligence. The patient presented microcephaly and specific abnormalities of the retina, with multiple diffuse oval areas of pigmentation and patches of chorioretinal atrophy associated with diffuse pigmentation of the fundus. Ophthalmological evaluations on the parents were normal. A computed tomography scan of the child's head showed slight dilation of lateral ventricles and basal cisterns without evidence of calcifications. We did not find any lymphedema in his hands and feet. He had postnatal growth retardation, severe mental retardation and cerebral palsy.CONCLUSIONS: The finding of chorioretinal lesions in a child with microcephaly should raise suspicions of the autosomal recessive form of microcephaly-chorioretinopathy syndrome, especially in cases with an atypical pattern of eye fundus and consanguinity. A specific diagnosis is essential for an appropriate clinical evaluation and for genetic counseling for the patients and their families.

  3. Amelogenesis imperfecta: a clinician's challenge.

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    Chamarthi, V; Varma, B R; Jayanthi, M

    2012-01-01

    Defective enamel formation can be explained as defects occurring at the stages of enamel formation. Quantitative defects in matrix formation leads to hypoplastic form of amelogenesis imperfecta. Inadequate mineralization of matrix leads to hypocalcification and hypomaturation variants. The demarcation of matrix formation and mineralization is not so distinct. This paper describes a case of a 7-year-old boy with amelogenesis imperfecta - Type IA i.e., hypoplastic pitted autosomal dominant.

  4. The Autosomal Recessive Inheritance of Hereditary Gingival Fibromatosis

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    Poulami Majumder

    2013-01-01

    Full Text Available Hereditary gingival fibromatosis (HGF is a rare condition which is marked by enlargement of gingival tissue that covers teeth to various extents leading to aesthetic disfigurement. This study presents a case of a 28-year-old female patient and 18-year-old male who belong to the same family suffering from HGF with chief complaint of overgrowing swelling gingiva. The presence of enlarged gingiva with the same eruption was found in their other family members with no concomitant drug or medical history, and the occurrence of HGF has been found in one generation of this family which may indicate the autosomal recessive inheritance pattern of HGF. Hereditary gingival fibromatosis is an idiopathic condition as its etiology is unknown and it was found to recur in some cases even after surgical treatment. Both patients underwent thorough oral prophylaxis and later surgical therapy to correct the deformity.

  5. Molecular and Cellular Basis of Autosomal Recessive Primary Microcephaly

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    Marine Barbelanne

    2014-01-01

    Full Text Available Autosomal recessive primary microcephaly (MCPH is a rare hereditary neurodevelopmental disorder characterized by a marked reduction in brain size and intellectual disability. MCPH is genetically heterogeneous and can exhibit additional clinical features that overlap with related disorders including Seckel syndrome, Meier-Gorlin syndrome, and microcephalic osteodysplastic dwarfism. In this review, we discuss the key proteins mutated in MCPH. To date, MCPH-causing mutations have been identified in twelve different genes, many of which encode proteins that are involved in cell cycle regulation or are present at the centrosome, an organelle crucial for mitotic spindle assembly and cell division. We highlight recent findings on MCPH proteins with regard to their role in cell cycle progression, centrosome function, and early brain development.

  6. Connexin 26 and autosomal recessive non-syndromic hearing loss

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    Mukherjee Monisha

    2003-01-01

    Full Text Available Prelingual deafness occurs with a frequency of 1 in 1000 live births and is divided into syndromic and non-syndromic forms contributing 40 and 60% respectively. Autosomal recessive non-syndromic hearing loss (ARNSHL is responsible for 80% cases of childhood deafness. Nearly all genes localized for ARNSHL cause prelingual, severe to profound, sensorineural hearing impairment. ARNSHL is genetically heterogeneous and at least 39 loci have been identified. The most significant finding to date has been the discovery of mutations in GJB2 gene at the DFNB1 locus on chromosome 13q12 as the major cause of profound prelingual deafness. This was first reported in a Tunisian family in 1994 and thereafter in many different countries. GJB2 gene encodes the gap-junction protein, connexin 26 (Cx26, mutations in which have become the first genetic marker of inherited hearing loss. Allele-specific polymerase chain reaction (AS-PCR, single stranded conformation polymorphism (SSCP and sequencing methods have been developed for the detection of mutations in Cx26 gene. In India as well, the Cx26 mutations are being screened in families with hearing impaired children using these molecular methods. Therefore, in order to create awareness among the clinicians and the affected families; we have attempted to review the Cx26 gene mutations responsible for autosomal recessive type of non-syndromic hearing loss. The efficacy and utility of Cx26 gene analysis might open the path to proper counseling of families for carrier detection and prenatal diagnosis. It may even facilitate the development of strategies in future for the treatment of this common genetic disorder.

  7. A missense mutation in ITGB6 causes pitted hypomineralized amelogenesis imperfecta.

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    Poulter, James A; Brookes, Steven J; Shore, Roger C; Smith, Claire E L; Abi Farraj, Layal; Kirkham, Jennifer; Inglehearn, Chris F; Mighell, Alan J

    2014-04-15

    We identified a family in which pitted hypomineralized amelogenesis imperfecta (AI) with premature enamel failure segregated in an autosomal recessive fashion. Whole-exome sequencing revealed a missense mutation (c.586C>A, p.P196T) in the I-domain of integrin-β6 (ITGB6), which is consistently predicted to be pathogenic by all available programmes and is the only variant that segregates with the disease phenotype. Furthermore, a recent study revealed that mice lacking a functional allele of Itgb6 display a hypomaturation AI phenotype. Phenotypic characterization of affected human teeth in this study showed areas of abnormal prismatic organization, areas of low mineral density and severe abnormal surface pitting in the tooth's coronal portion. We suggest that the pathogenesis of this form of AI may be due to ineffective ligand binding of ITGB6 resulting in either compromised cell-matrix interaction or compromised ITGB6 activation of transforming growth factor-β (TGF-β) impacting indirectly on ameloblast-ameloblast interactions and proteolytic processing of extracellular matrix proteins via MMP20. This study adds to the list of genes mutated in AI and further highlights the importance of cell-matrix interactions during enamel formation.

  8. FOXE3 plays a significant role in autosomal recessive microphthalmia.

    Science.gov (United States)

    Reis, Linda M; Tyler, Rebecca C; Schneider, Adele; Bardakjian, Tanya; Stoler, Joan M; Melancon, Serge B; Semina, Elena V

    2010-03-01

    FOXE3 forkhead transcription factor is essential to lens development in vertebrates. The eyes of Foxe3/foxe3-deficient mice and zebrafish fail to develop normally. In humans, autosomal dominant and recessive mutations in FOXE3 have been associated with variable phenotypes including anterior segment anomalies, cataract, and microphthalmia. We undertook sequencing of FOXE3 in 116 probands with a spectrum of ocular defects ranging from anterior segment dysgenesis and cataract to anophthalmia/microphthalmia. Recessive mutations in FOXE3 were found in four of 26 probands affected with bilateral microphthalmia (15% of all bilateral microphthalmia and 100% of consanguineous families with this phenotype). FOXE3-positive microphthalmia was accompanied by aphakia and/or corneal defects; no other associated systemic anomalies were observed in FOXE3-positive families. The previously reported c.720C > A (p.C240X) nonsense mutation was identified in two additional families in our sample and therefore appears to be recurrent, now reported in three independent microphthalmia families of varied ethnic backgrounds. Several missense variants were identified at varying frequencies in patient and control groups with some apparently being race-specific, which underscores the importance of utilizing race/ethnicity-matched control populations in evaluating the relevance of genetic screening results. In conclusion, FOXE3 mutations represent an important cause of nonsyndromic autosomal recessive bilateral microphthalmia.

  9. Interradicular dentin dysplasia associated with amelogenesis imperfecta with taurodontism or trichodentoosseous syndrome: A diagnostic dilemma

    Directory of Open Access Journals (Sweden)

    Veda Hegde

    2014-01-01

    Full Text Available Amelogenesis imperfecta is a hereditary disorder with diverse clinical presentation, where enamel is the tissue that is primarily affected either quantitatively or qualitatively. Hypomaturation/hypoplastic amelogenesis imperfecta with taurodontism is a rare variant of amelogenesis imperfecta which is often confused with trichodentoosseous syndrome. We report a rare case of hereditary enamel defect with taurodontism associated with interradicular dentin dysplasia.

  10. Interradicular dentin dysplasia associated with amelogenesis imperfecta with taurodontism or trichodentoosseous syndrome: a diagnostic dilemma.

    Science.gov (United States)

    Hegde, Veda; Srikanth, K

    2014-01-01

    Amelogenesis imperfecta is a hereditary disorder with diverse clinical presentation, where enamel is the tissue that is primarily affected either quantitatively or qualitatively. Hypomaturation/hypoplastic amelogenesis imperfecta with taurodontism is a rare variant of amelogenesis imperfecta which is often confused with trichodentoosseous syndrome. We report a rare case of hereditary enamel defect with taurodontism associated with interradicular dentin dysplasia.

  11. An exome sequencing strategy to diagnose lethal autosomal recessive disorders.

    Science.gov (United States)

    Ellard, Sian; Kivuva, Emma; Turnpenny, Peter; Stals, Karen; Johnson, Matthew; Xie, Weijia; Caswell, Richard; Lango Allen, Hana

    2015-03-01

    Rare disorders resulting in prenatal or neonatal death are genetically heterogeneous. For some conditions, affected fetuses can be diagnosed by ultrasound scan, but this is not usually possible until mid-gestation. There is often limited fetal DNA available for investigation. We investigated a strategy for diagnosing autosomal recessive lethal disorders in non-consanguineous pedigrees with multiple affected fetuses. Exome sequencing was performed to identify genes where each parent is heterozygous for a rare non-synonymous-coding or splicing variant. Putative pathogenic variants were tested for cosegregation in affected fetuses and unaffected siblings. In eight couples of European ancestry, we found on average 1.75 genes (range 0-4) where both parents were heterozygous for rare potentially deleterious variants. A proof-of-principle study detected heterozygous DYNC2H1 variants in a couple whose five fetuses had short-rib polydactyly. Prospective analysis of two couples with multiple pregnancy terminations for fetal akinesia syndrome was performed and a diagnosis was obtained in both the families. The first couple were each heterozygous for a previously reported GLE1 variant, p.Arg569His or p.Val617Met; both were inherited by their two affected fetuses. The second couple were each heterozygous for a novel RYR1 variant, c.14130-2A>G or p.Ser3074Phe; both were inherited by their three affected fetuses but not by their unaffected child. Biallelic GLE1 and RYR1 disease-causing variants have been described in other cases with fetal akinesia syndrome. We conclude that exome sequencing of parental samples can be an effective tool for diagnosing lethal recessive disorders in outbred couples. This permits early prenatal diagnosis in future pregnancies.

  12. Autosomal recessive agammaglobulinemia: a novel non-sense mutation in CD79a.

    Science.gov (United States)

    Khalili, Abbas; Plebani, Alessandro; Vitali, Massimiliano; Abolhassani, Hassan; Lougaris, Vassilios; Mirminachi, Babak; Rezaei, Nima; Aghamohammadi, Asghar

    2014-02-01

    This study describes the fifth case worldwide of autosomal recessive agammaglobulinemia due to a novel non-sense mutation in CD79a gene with a severe unusual onset due to an invasive central nervous system infection.

  13. CNGB3 mutations account for 50% of all cases with autosomal recessive achromatopsia.

    NARCIS (Netherlands)

    Kohl, S.; Varsanyi, B.; Antunes, G.A.; Baumann, B.; Hoyng, C.B.; Jagle, H.; Rosenberg, T.; Kellner, U.; Lorenz, B.; Salati, R.; Jurklies, B.; Farkas, A.; Andreasson, S.; Weleber, R.G.; Jacobson, S.G.; Rudolph, G.; Castellan, C.; Dollfus, H.; Legius, E.; Anastasi, M.; Bitoun, P.; Lev, D.; Sieving, P.A.; Munier, F.L.; Zrenner, E.; Sharpe, L.T.; Cremers, F.P.M.; Wissinger, B.

    2005-01-01

    Achromatopsia is a congenital, autosomal recessively inherited disorder characterized by a lack of color discrimination, low visual acuity (<0.2), photophobia, and nystagmus. Mutations in the genes for CNGA3, CNGB3, and GNAT2 have been associated with this disorder. Here, we analyzed the spectrum

  14. Autosomal recessive disorder with retardation of growth, mental deficiency, ptosis, pectus excavatum and camptodactyly

    Energy Technology Data Exchange (ETDEWEB)

    Khaldi, F.; Bennaceur, B.; Hammou, A.; Hamza, M.; Gharbi, H.A.

    1988-07-01

    Two strikingly similar brothers issued from consanguineous parents in the second degree present the following patterns of anomalies: Retardation of growth, mental deficiency, ocular abnormalities, pectus excavatum and camptodactyly. The ocular abnormalities include ptosis, microphthalmia and hypertelorism. No endocrine or metabolic aberrations are found. The authors conclude that the disorder has probably an autosomal recessive mode of transmission.

  15. Linkage of DFNB1 to non-syndromic neurosensory autosomal-recessive deafness in Mediterranean families

    NARCIS (Netherlands)

    Gasparini, P; Estivill, [No Value; Volpini, [No Value; Totaro, A; CastellviBel, S; Govea, N; Mila, M; DellaMonica, M; Ventruto, [No Value; DeBenedetto, M; Stanziale, P; Zelante, L; Mansfield, ES; Sandkuijl, L; Surrey, S; Fortina, P

    1997-01-01

    Recent studies show a susceptibility locus (DFNB1) responsible for non-syndromic neurosensory autosomal-recessive deafness (NSRD) mapping to the pericentromeric region of chromosome 13q, In order to better understand the frequency with which DFNB1 is the gene for deafness in our patient population a

  16. Autosomal recessive cerebellar ataxia caused by mutations in the PEX2 gene

    NARCIS (Netherlands)

    C. Sevin; S. Ferdinandusse; H.R. Waterham; R.J. Wanders; P. Aubourg

    2011-01-01

    ABSTRACT: OBJECTIVE: To expand the spectrum of genetic causes of autosomal recessive cerebellar ataxia (ARCA). Case report: Two brothers are described who developed progressive cerebellar ataxia at 3 1/2 and 18 years, respectively. After ruling out known common genetic causes of ARCA, analysis of bl

  17. Progeria (Hutchison-Gilford syndrome) in siblings: in an autosomal recessive pattern of inheritance.

    Science.gov (United States)

    Raghu, T Y; Venkatesulu, G A; Kantharaj, G R; Suresh, T; Veeresh, V; Hanumanthappa, Y

    2001-01-01

    Progeria is an autosomal dominant, premature aging syndrome. Six and three year old female siblings had sclerodermatous changes over the extremities, alopecia, beaked nose, prominent veins and bird-like facies. Radiological features were consistent with features of progeria. The present case highlights rarity of progeria in siblings with a possible autosomal recessive pattern.

  18. A Nonsense Mutation in PDE6H Causes Autosomal-Recessive Incomplete Achromatopsia.

    NARCIS (Netherlands)

    Kohl, S.; Coppieters, F.; Meire, F.; Schaich, S.; Roosing, S.; Brennenstuhl, C.; Bolz, S.; Genderen, M.M. van; Riemslag, F.C.; Lukowski, R.; Hollander, A.I. den; Cremers, F.P.M.; Baere, E. de; Hoyng, C.B.; Wissinger, B.

    2012-01-01

    Achromatopsia (ACHM) is an autosomal-recessive retinal dystrophy characterized by color blindness, photophobia, nystagmus, and severely reduced visual acuity. Its prevalence has been estimated to about 1 in 30,000 individuals. Four genes, GNAT2, PDE6C, CNGA3, and CNGB3, have been implicated in ACHM,

  19. Progeria (Hutchison - Gilford syndrome in siblings: In an autosomal recessive pattern of inheritance

    Directory of Open Access Journals (Sweden)

    Raghu Tanjore

    2001-09-01

    Full Text Available Progeria is an autosomal dominant, premature aging syndrome. Six and three year old female siblings had sclcrodermatous changes over the extremities, alopecia, beaked nose, prominent veins and bird-like facies. Radiological features were consistent with features of progeria. The present case highlights rarity of progeria in siblings with a possible autosomal recessive pattern.

  20. Boy with autosomal recessive polycystic kidney and autosomal dominant polycystic liver disease.

    NARCIS (Netherlands)

    Zingg-Schenk, A.; Caduff, J.; Azzarello-Burri, S.; Bergmann, C.; Drenth, J.P.H.; Neuhaus, T.J.

    2012-01-01

    BACKGROUND: Autosomal recessive polycystic kidney disease (ARPKD) shows a great phenotypic variability between patients, ranging from perinatal demise to mildly affected adults. Autosomal dominant polycystic liver disease (PCLD) does not manifest in childhood. CASE-DIAGNOSIS/TREATMENT: A boy was rep

  1. ALS5/SPG11/KIAA1840 mutations cause autosomal recessive axonal Charcot-Marie-Tooth disease.

    Science.gov (United States)

    Montecchiani, Celeste; Pedace, Lucia; Lo Giudice, Temistocle; Casella, Antonella; Mearini, Marzia; Gaudiello, Fabrizio; Pedroso, José L; Terracciano, Chiara; Caltagirone, Carlo; Massa, Roberto; St George-Hyslop, Peter H; Barsottini, Orlando G P; Kawarai, Toshitaka; Orlacchio, Antonio

    2016-01-01

    Charcot-Marie-Tooth disease is a group of hereditary peripheral neuropathies that share clinical characteristics of progressive distal muscle weakness and atrophy, foot deformities, distal sensory loss, as well as diminished tendon reflexes. Hundreds of causative DNA changes have been found, but much of the genetic basis of the disease is still unexplained. Mutations in the ALS5/SPG11/KIAA1840 gene are a frequent cause of autosomal recessive hereditary spastic paraplegia with thin corpus callosum and peripheral axonal neuropathy, and account for ∼ 40% of autosomal recessive juvenile amyotrophic lateral sclerosis. The overlap of axonal Charcot-Marie-Tooth disease with both diseases, as well as the common autosomal recessive inheritance pattern of thin corpus callosum and axonal Charcot-Marie-Tooth disease in three related patients, prompted us to analyse the ALS5/SPG11/KIAA1840 gene in affected individuals with autosomal recessive axonal Charcot-Marie-Tooth disease. We investigated 28 unrelated families with autosomal recessive axonal Charcot-Marie-Tooth disease defined by clinical, electrophysiological, as well as pathological evaluation. Besides, we screened for all the known genes related to axonal autosomal recessive Charcot-Marie-Tooth disease (CMT2A2/HMSN2A2/MFN2, CMT2B1/LMNA, CMT2B2/MED25, CMT2B5/NEFL, ARCMT2F/dHMN2B/HSPB1, CMT2K/GDAP1, CMT2P/LRSAM1, CMT2R/TRIM2, CMT2S/IGHMBP2, CMT2T/HSJ1, CMTRID/COX6A1, ARAN-NM/HINT and GAN/GAN), for the genes related to autosomal recessive hereditary spastic paraplegia with thin corpus callosum and axonal peripheral neuropathy (SPG7/PGN, SPG15/ZFYVE26, SPG21/ACP33, SPG35/FA2H, SPG46/GBA2, SPG55/C12orf65 and SPG56/CYP2U1), as well as for the causative gene of peripheral neuropathy with or without agenesis of the corpus callosum (SLC12A6). Mitochondrial disorders related to Charcot-Marie-Tooth disease type 2 were also excluded by sequencing POLG and TYMP genes. An additional locus for autosomal recessive Charcot

  2. Fine genetic mapping of a gene for autosomal recessive retinitis pigmentosa on chromosome 6p21

    Energy Technology Data Exchange (ETDEWEB)

    Shugart, Yin Y.; Banerjee, P.; Knowles, J.A. [Columbia Univ., New York, NY (United States)] [and others

    1995-08-01

    The inherited retinal degenerations known as retinitis pigmentosa (RP) can be caused by mutations at many different loci and can be inherited as an autosomal recessive, autosomal dominant, or X-linked recessive trait. Two forms of autosomal recessive (arRP) have been reported to cosegregate with mutations in the rhodopsin gene and the beta-subunit of rod phosphodiesterase on chromosome 4p. Genetic linkage has been reported on chromosomes 6p and 1q. In a large Dominican family, we reported an arRp gene near the region of the peripherin/RDS gene. Four recombinations were detected between the disease locus and an intragenic marker derived from peripherin/RDS. 26 refs., 2 figs., 1 tab.

  3. Autosomal recessive chronic granulomatous disease caused by deletion at a dinucleotide repeat

    Energy Technology Data Exchange (ETDEWEB)

    Casimir, C.M.; Bu-Ghanim, H.N.; Rowe, P.; Segal, A.W. (University College London (England)); Rodaway, A.R.F.; Bentley, D.L. (Imperial Cancer Research Fund Lab., London (England))

    1991-04-01

    Chronic granulomatous disease (CGD) is a rare inherited condition rendering neutrophils incapable of killing invading pathogens. This condition is due to the failure of a multicomponent microbicidal oxidase that normally yields a low-midpoint-potential b cytochrome (cytochrome b{sub 245}). Although defects in the X chromosome-linked cytochrome account for the majority of CGD patients, as many as 30% of CGD cases are due to an autosomal recessive disease. Of these, {gt}90% have been shown to be defective in the synthesis of a 47-kDa cytosolic component of the oxidase. The authors demonstrate here in three unrelated cases of autosomal recessive CGD that the identical underlying molecular lesion is a dinucleotide deletion at a GTGT tandem repeat, corresponding to the acceptor site of the first intron - exon junction. Slippage of the DNA duplex at this site may contribute to the high frequency of defects in this gene.

  4. [Autosomal-recessive renal cystic disease and congenital hepatic fibrosis: clinico-anatomic case].

    Science.gov (United States)

    Rostol'tsev, K V; Burenkov, R A; Kuz'micheva, I A

    2012-01-01

    Clinico-anatomic observation of autosomal-recessive renal cystic disease and congenital hepatic fibrosis at two fetuses from the same family was done. Mutation of His3124Tyr in 58 exon of PKHD1 gene in heterozygous state was found out. The same pathomorphological changes in the epithelium of cystic renal tubules and bile ducts of the liver were noted. We suggest that the autopsy research of fetuses with congenital abnormalities, detected after prenatal ultrasonic screening, has high diagnostic importance.

  5. New form of autosomal-recessive axonal hereditary sensory motor neuropathy.

    Science.gov (United States)

    Eckhardt, S M; Hicks, E M; Herron, B; Morrison, P J; Aicardi, J

    1998-09-01

    Two siblings, a male and a female, had severe axonal neuropathy and sideroblastic anemia. Despite a distinct clinical picture with areflexia, ataxia, hypotonia, optic atrophy, and progressive sensory neural hearing loss, no definite diagnosis could be reached and the older sibling died at 6 years of age of respiratory failure. It is proposed that the two affected siblings have a new form of autosomal-recessive axonal hereditary sensory motor neuropathy.

  6. More Than Ataxia: Hyperkinetic Movement Disorders in Childhood Autosomal Recessive Ataxia Syndromes

    OpenAIRE

    2016-01-01

    Background The autosomal recessive ataxias are a heterogeneous group of disorders that are characterized by complex neurological features in addition to progressive ataxia. Hyperkinetic movement disorders occur in a significant proportion of patients, and may sometimes be the presenting motor symptom. Presentations with involuntary movements rather than ataxia are diagnostically challenging, and are likely under-recognized. Methods A PubMed literature search was performed in October 2015 util...

  7. Macroepiphyseal dysplasia with symptomatic osteoporosis, wrinkled skin, and aged appearance: A presumed autosomal recessive condition

    Energy Technology Data Exchange (ETDEWEB)

    McAlister, W.H.; Coe, J.D.; Whyte, M.P.

    1986-01-01

    We report our detailed investigation of a 7-1/2-year-old girl with short stature, aged appearance, decreased subcutaneous fat and muscle mass, dry coarse hair, foot deformities, macroepiphyses with prominent but lax joints, and osteoporosis with recurrent fractures who is the offspring of first cousins. This constellation of abnormalities differs from previously reported cases where macroepiphyses were a prominent finding. Our patient appears, therefore, to have a new, autosomal recessively inherited, syndrome.

  8. Improved Structure and Function in Autosomal Recessive Polycystic Rat Kidneys with Renal Tubular Cell Therapy.

    Science.gov (United States)

    Kelly, K J; Zhang, Jizhong; Han, Ling; Kamocka, Malgorzata; Miller, Caroline; Gattone, Vincent H; Dominguez, Jesus H

    2015-01-01

    Autosomal recessive polycystic kidney disease is a truly catastrophic monogenetic disease, causing death and end stage renal disease in neonates and children. Using PCK female rats, an orthologous model of autosomal recessive polycystic kidney disease harboring mutant Pkhd1, we tested the hypothesis that intravenous renal cell transplantation with normal Sprague Dawley male kidney cells would improve the polycystic kidney disease phenotype. Cytotherapy with renal cells expressing wild type Pkhd1 and tubulogenic serum amyloid A1 had powerful and sustained beneficial effects on renal function and structure in the polycystic kidney disease model. Donor cell engraftment and both mutant and wild type Pkhd1 were found in treated but not control PCK kidneys 15 weeks after the final cell infusion. To examine the mechanisms of global protection with a small number of transplanted cells, we tested the hypothesis that exosomes derived from normal Sprague Dawley cells can limit the cystic phenotype of PCK recipient cells. We found that renal exosomes originating from normal Sprague Dawley cells carried and transferred wild type Pkhd1 mRNA to PCK cells in vivo and in vitro and restricted cyst formation by cultured PCK cells. The results indicate that transplantation with renal cells containing wild type Pkhd1 improves renal structure and function in autosomal recessive polycystic kidney disease and may provide an intra-renal supply of normal Pkhd1 mRNA.

  9. Improved Structure and Function in Autosomal Recessive Polycystic Rat Kidneys with Renal Tubular Cell Therapy.

    Directory of Open Access Journals (Sweden)

    K J Kelly

    Full Text Available Autosomal recessive polycystic kidney disease is a truly catastrophic monogenetic disease, causing death and end stage renal disease in neonates and children. Using PCK female rats, an orthologous model of autosomal recessive polycystic kidney disease harboring mutant Pkhd1, we tested the hypothesis that intravenous renal cell transplantation with normal Sprague Dawley male kidney cells would improve the polycystic kidney disease phenotype. Cytotherapy with renal cells expressing wild type Pkhd1 and tubulogenic serum amyloid A1 had powerful and sustained beneficial effects on renal function and structure in the polycystic kidney disease model. Donor cell engraftment and both mutant and wild type Pkhd1 were found in treated but not control PCK kidneys 15 weeks after the final cell infusion. To examine the mechanisms of global protection with a small number of transplanted cells, we tested the hypothesis that exosomes derived from normal Sprague Dawley cells can limit the cystic phenotype of PCK recipient cells. We found that renal exosomes originating from normal Sprague Dawley cells carried and transferred wild type Pkhd1 mRNA to PCK cells in vivo and in vitro and restricted cyst formation by cultured PCK cells. The results indicate that transplantation with renal cells containing wild type Pkhd1 improves renal structure and function in autosomal recessive polycystic kidney disease and may provide an intra-renal supply of normal Pkhd1 mRNA.

  10. THE SYNDROME OF AUTOSOMAL RECESSIVE PONTOCEREBELLAR HYPOPLASIA, MICROCEPHALY, AND EXTRAPYRAMIDAL DYSKINESIA (PONTOCEREBELLAR HYPOPLASIA TYPE-2) - COMPILED DATA FROM 10 PEDIGREES

    NARCIS (Netherlands)

    BARTH, PG; BLENNOW, G; LENARD, HG; BEGEER, JH; VANDERKLEY, JM; HANEFELD, F; PETERS, ACB; Valk, J.

    1995-01-01

    The syndrome of autosomal recessive pontocerebellar hypoplasia, microcephaly, severely impaired mental and motor development, and extrapyramidal dyskinesia is a distinct system degeneration, previously designated pontocerebellar hypoplasia type 2 (PCH-2). To further characterize its clinical and neu

  11. Coincidence the Autosomal Recessive Polycystic Kidney Disease With Placenta Membranacea (A Probably Genetic Relation with PKHD1 Gene

    Directory of Open Access Journals (Sweden)

    Ehsan Hosseini

    2016-05-01

    Full Text Available Placenta membranacea is one of the most barley anomalies happens in pregnancy defined by chorionic villi (partially or completely covered the fetus membrane. Autosomal recessive polycystic kidney disease in fetus is also a rare case with an incidence of 1: 20,000 live births resulting in a 30% death rate in neonates. In this case for the first time, we reported a placenta membranacea and autosomal recessive polycystic kidney disease occurred with together. A 25-year-old woman was admitted at 16 weeks of gestation for inducing abortion with autosomal recessive polycystic kidney disease in fetus diagnosed in routine sonography fellowship. Post-delivery examination revealed a placenta totally enveloped the fetus, oligohydramnious and bilateral enlarged polycystic kidneys of fetus. Histological study indicated umbilicus has only one artery and one vein as well as autosomal recessive polycystic kidney disease and directly attachment of chorionic villi to fetal membrane eventually diagnosed as complete placenta membranacea. The etiology of placenta membranacea is not completely clarified. As autosomal recessive polycystic kidney disease is a result of mutation in PKHD1 gene, so our finding may be initiates a new investigation about genetic relation between placenta membranacea and autosomal recessive polycystic kidney disease.

  12. Disease: H00615 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available Lyroudia K Genes and related proteins involved in amelogenesis imperfecta. J Dent Res 84:1117-26 (2005) PMI...se autosomal-recessive hypomaturation amelogenesis imperfecta. Am J Hum Genet 85:699-705 (2009) PMID:1825222...ilies with autosomal-dominant hypocalcified amelogenesis imperfecta. Am J Hum Genet 82:489-94 (2008) ...

  13. Mutations in c10orf11, a melanocyte-differentiation gene, cause autosomal-recessive albinism.

    Science.gov (United States)

    Grønskov, Karen; Dooley, Christopher M; Østergaard, Elsebet; Kelsh, Robert N; Hansen, Lars; Levesque, Mitchell P; Vilhelmsen, Kaj; Møllgård, Kjeld; Stemple, Derek L; Rosenberg, Thomas

    2013-03-07

    Autosomal-recessive albinism is a hypopigmentation disorder with a broad phenotypic range. A substantial fraction of individuals with albinism remain genetically unresolved, and it has been hypothesized that more genes are to be identified. By using homozygosity mapping of an inbred Faroese family, we identified a 3.5 Mb homozygous region (10q22.2-q22.3) on chromosome 10. The region contains five protein-coding genes, and sequencing of one of these, C10orf11, revealed a nonsense mutation that segregated with the disease and showed a recessive inheritance pattern. Investigation of additional albinism-affected individuals from the Faroe Islands revealed that five out of eight unrelated affected persons had the nonsense mutation in C10orf11. Screening of a cohort of autosomal-recessive-albinism-affected individuals residing in Denmark showed a homozygous 1 bp duplication in C10orf11 in an individual originating from Lithuania. Immunohistochemistry showed localization of C10orf11 in melanoblasts and melanocytes in human fetal tissue, but no localization was seen in retinal pigment epithelial cells. Knockdown of the zebrafish (Danio rerio) homolog with the use of morpholinos resulted in substantially decreased pigmentation and a reduction of the apparent number of pigmented melanocytes. The morphant phenotype was rescued by wild-type C10orf11, but not by mutant C10orf11. In conclusion, we have identified a melanocyte-differentiation gene, C10orf11, which when mutated causes autosomal-recessive albinism in humans.

  14. A novel deletion mutation in ASPM gene in an Iranian family with autosomal recessive primary microcephaly

    Directory of Open Access Journals (Sweden)

    Elinaz AKBARIAZAR

    2013-06-01

    Full Text Available How to Cite This Article: Akbarizar E, Ebrahimpour M, Akbari S, Arzhanghi S, Abedini SS, Najmabadi H, Kahrizi K. A Novel Deletion Mutation in ASPM Gene in an Iranian Family with Autosomal Recessive Primary Microcephaly. Iran J Child Neurol.  2013 Spring;7(2:23-30. ObjectiveAutosomal recessive primary microcephaly (MCPH is a neurodevelopmental and genetically heterogeneous disorder with decreased head circumference due to the abnormality in fetal brain growth. To date, nine loci and nine genes responsible for the situation have been identified. Mutations in the ASPM gene (MCPH5 is the most common cause of MCPH. The ASPM gene with 28 exons is essential for normal mitotic spindle function in embryonic neuroblasts.Materials & MethodsWe have ascertained twenty-two consanguineous families withintellectual disability and different ethnic backgrounds from Iran. Ten out of twenty-two families showed primary microcephaly in clinical examination. We investigated MCPH5 locus using homozygosity mapping by microsatellite marker. ResultSequence analysis of exon 8 revealed a deletion of nucleotide (T in donor site of splicing site of ASPM in one family. The remaining nine families were not linked to any of the known loci. More investigation will be needed to detect the causative defect in these families.ConlusionWe detected a novel mutation in the donor splicing site of exon 8 of the ASPM gene. This deletion mutation can alter the ASPM transcript leading to functional impairment of the gene product. References1. Pattison L, Crow YJ, Deeble VJ, Jackson AP, Jafri H, Rashid Y, et al. A Fifth Locus for Primary Autosomal Recessive Microcephaly Maps to Chromosome 1q31. Am J Hum Genet 2000;67(6:1578-80.2. Darvish H, Esmaeeli-Nieh S, Monajemi G, Mohseni M, Ghasemi-Firouzabadi S, Abedini S, et al. A clinical and molecular genetic study of 112 Iranian families with primary microcephaly. Journal of Medical Genetics 2010;47(12:823-8.3. Tolmie JL, M M, JB S, D D, JM C

  15. Founder mutation in dystonin-e underlying autosomal recessive epidermolysis bullosa simplex in Kuwait.

    Science.gov (United States)

    Takeichi, T; Nanda, A; Liu, L; Aristodemou, S; McMillan, J R; Sugiura, K; Akiyama, M; Al-Ajmi, H; Simpson, M A; McGrath, J A

    2015-02-01

    Only two homozygous nonsense mutations in the epidermal isoform of the dystonin gene, DST-e, have been reported previously in autosomal recessive epidermolysis bullosa simplex (EBS); the affected pedigrees were Kuwaiti and Iranian. This subtype of EBS is therefore considered to be a rare clinicopathological entity. In this study, we identified four seemingly unrelated Kuwaiti families in which a total of seven individuals had predominantly acral trauma-induced blistering since infancy. All affected individuals were homozygous for the mutation p.Gln1124* in DST-e, the same mutation that was identified in the originally reported family from Kuwait. Haplotype analysis in the five pedigrees (including the previous case) revealed a shared block of ~60 kb of genomic DNA across the site of the mutation, consistent with a founder effect. Most heterozygotes had no clinical abnormalities although one subject had mild transient skin fragility during childhood, an observation noted in the previously reported Iranian pedigree, suggesting that the condition may also be semidominant in some pedigrees rather than purely autosomal recessive. Our study reveals propagation of a mutant ancestral allele in DST-e throughout Kuwait, indicating that this subtype of EBS may be more common in Kuwait, and perhaps other Middle Eastern countries, than is currently appreciated.

  16. Autosomal recessive dilated cardiomyopathy due to DOLK mutations results from abnormal dystroglycan O-mannosylation.

    Directory of Open Access Journals (Sweden)

    Dirk J Lefeber

    2011-12-01

    Full Text Available Genetic causes for autosomal recessive forms of dilated cardiomyopathy (DCM are only rarely identified, although they are thought to contribute considerably to sudden cardiac death and heart failure, especially in young children. Here, we describe 11 young patients (5-13 years with a predominant presentation of dilated cardiomyopathy (DCM. Metabolic investigations showed deficient protein N-glycosylation, leading to a diagnosis of Congenital Disorders of Glycosylation (CDG. Homozygosity mapping in the consanguineous families showed a locus with two known genes in the N-glycosylation pathway. In all individuals, pathogenic mutations were identified in DOLK, encoding the dolichol kinase responsible for formation of dolichol-phosphate. Enzyme analysis in patients' fibroblasts confirmed a dolichol kinase deficiency in all families. In comparison with the generally multisystem presentation in CDG, the nonsyndromic DCM in several individuals was remarkable. Investigation of other dolichol-phosphate dependent glycosylation pathways in biopsied heart tissue indicated reduced O-mannosylation of alpha-dystroglycan with concomitant functional loss of its laminin-binding capacity, which has been linked to DCM. We thus identified a combined deficiency of protein N-glycosylation and alpha-dystroglycan O-mannosylation in patients with nonsyndromic DCM due to autosomal recessive DOLK mutations.

  17. Autosomal recessive congenital cataract, intellectual disability phenotype linked to STX3 in a consanguineous Tunisian family.

    Science.gov (United States)

    Chograni, M; Alkuraya, F S; Ourteni, I; Maazoul, F; Lariani, I; Chaabouni, H B

    2015-09-01

    The aim of this study is to investigate the genetic basis of autosomal recessive congenital cataract and intellectual disability phenotype in a consanguineous Tunisian family. The whole genome scan of the studied family was performed with single nucleotide polymorphisms (SNPs). The resulted runs of homozygosity (ROH) were analyzed through the integrated Systems Tool for Eye gene discovery (iSyTE) in order to prioritize candidate genes associated with congenital cataract. Selected genes were amplified and sequenced. Bioinformatic analysis was conducted to predict the function of the mutant gene. We identified a new specific lens gene named syntaxin 3 linked to the studied phenotype. The direct sequencing of this gene revealed a novel missense mutation c.122A>G which results in p.E41G. Bioinformatic analysis suggested a deleterious effect of this mutation on protein structure and function. Here, we report for the first time a missense mutation of a novel lens specific gene STX3 in a phenotype associating autosomal recessive congenital cataract and intellectual disability.

  18. Mutations in CERS3 cause autosomal recessive congenital ichthyosis in humans.

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    Franz P W Radner

    2013-06-01

    Full Text Available Autosomal recessive congenital ichthyosis (ARCI is a rare genetic disorder of the skin characterized by abnormal desquamation over the whole body. In this study we report four patients from three consanguineous Tunisian families with skin, eye, heart, and skeletal anomalies, who harbor a homozygous contiguous gene deletion syndrome on chromosome 15q26.3. Genome-wide SNP-genotyping revealed a homozygous region in all affected individuals, including the same microdeletion that partially affects two coding genes (ADAMTS17, CERS3 and abolishes a sequence for a long non-coding RNA (FLJ42289. Whereas mutations in ADAMTS17 have recently been identified in autosomal recessive Weill-Marchesani-like syndrome in humans and dogs presenting with ophthalmologic, cardiac, and skeletal abnormalities, no disease associations have been described for CERS3 (ceramide synthase 3 and FLJ42289 so far. However, analysis of additional patients with non-syndromic ARCI revealed a splice site mutation in CERS3 indicating that a defect in ceramide synthesis is causative for the present skin phenotype of our patients. Functional analysis of patient skin and in vitro differentiated keratinocytes demonstrated that mutations in CERS3 lead to a disturbed sphingolipid profile with reduced levels of epidermis-specific very long-chain ceramides that interferes with epidermal differentiation. Taken together, these data present a novel pathway involved in ARCI development and, moreover, provide the first evidence that CERS3 plays an essential role in human sphingolipid metabolism for the maintenance of epidermal lipid homeostasis.

  19. Autosomal recessive transmission of MYBPC3 mutation results in malignant phenotype of hypertrophic cardiomyopathy.

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    Yilu Wang

    Full Text Available BACKGROUND: Hypertrophic cardiomyopathy (HCM due to mutations in genes encoding sarcomere proteins is most commonly inherited as an autosomal dominant trait. Since nearly 50% of HCM cases occur in the absence of a family history, a recessive inheritance pattern may be involved. METHODS: A pedigree was identified with suspected autosomal recessive transmission of HCM. Twenty-six HCM-related genes were comprehensively screened for mutations in the proband with targeted second generation sequencing, and the identified mutation was confirmed with bi-directional Sanger sequencing in all family members and 376 healthy controls. RESULTS: A novel missense mutation (c.1469G>T, p.Gly490Val in exon 17 of MYBPC3 was identified. Two siblings with HCM were homozygous for this mutation, whereas other family members were either heterozygous or wild type. Clinical evaluation showed that both homozygotes manifested a typical HCM presentation, but none of others, including 5 adult heterozygous mutation carriers up to 71 years of age, had any clinical evidence of HCM. CONCLUSIONS: Our data identified a MYBPC3 mutation in HCM, which appeared autosomal recessively inherited in this family. The absence of a family history of clinical HCM may be due to not only a de novo mutation, but also recessive mutations that failed to produce a clinical phenotype in heterozygous family members. Therefore, consideration of recessive mutations leading to HCM is essential for risk stratification and genetic counseling.

  20. A new autosomal recessive disorder of bilateral frontotemporal pachygyria without microcephaly: Report of a case and review of literature

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    Phadke Shubha

    2007-01-01

    Full Text Available Pachygyria is a disorder of neuronal migration. We report an Indian family with four siblings with developmental delay, infrequent seizures, normal head size and mild to moderate mental retardation. Two of them had bilaterally symmetrical frontotemporal pachygyria. Dysmorphism and neurological signs were absent in the affected subjects. Affected male and female siblings with normal parents suggests autosomal recessive mode of inheritance. We believe these cases represent a new autosomal recessive disorder of neuronal migration. Other similar cases of lissencephaly are reviewed.

  1. A Linkage Study in 8 Pakistani Families Segregating as Autosomal Recessive Primary Microcephaly

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    M. Hassanullah

    2011-07-01

    Full Text Available The current study was designed to find the most frequent MCPH phenotype in inbred Pakistani families. Primary microcephaly is marked by small brain size and is usually inherited as recessive trait. In the present study, we performed linkage analysis on 8 Pakistani families with autosomal recessive primary microcephaly (MCPH and linked 6 of them to known MCPH genes/loci like MCPH1 (Microcephalin, MCPH3 (CDK5RAP2 and MCPH5 (ASPM. Majority of the families showed linkage with MCPH5, the most common MCPH locus in Pakistan. The linked families were then subjected to mutational analysis, revealing a previously known G to A transition at nucleotide position 3978 in exon 17 of ASPM gene in three of the families. To decrease its incidence, it is indispensible to train the people of the possible devastating outcome of cousin marriages and to find the carriers through carrier screening programs.

  2. Autosomal recessive chronic granulomatous disease presenting with cutaneous dermatoses and ocular infection.

    Science.gov (United States)

    Low, L C M; Manson, A L; Hardman, C; Carton, J; Seneviratne, S L; Ninis, N

    2013-04-01

    Dermatoses such as eczematous dermatitis and cutaneous infection are recognized presentations of primary immunodeficiency (PID). However, atopic dermatitis affects approximately 10% of infants, and cutaneous infections are not uncommon in children, therefore the challenge for the dermatologist is to distinguish the few patients that have PID from the many that do not. We report on a 6-year-old girl who was ultimately diagnosed with autosomal recessive chronic granulomatous disease (AR-CGD) after presenting to various hospitals with dermatitis, scalp plaques recalcitrant to treatment, and recurrent infections over a 3-year period, and describe some aspects of her diagnosis and management. This report highlights the importance of considering rare disorders such as AR-CGD in the differential diagnosis of recurrent or recalcitrant dermatological infections in children.

  3. Birth prevalence and mutation spectrum in danish patients with autosomal recessive albinism

    DEFF Research Database (Denmark)

    Grønskov, Karen; Ek, Jakob; Sand, Annie;

    2009-01-01

    PURPOSE: The study was initiated to investigate the mutation spectrum of four OCA genes and to calculate the birth prevalence in patients with autosomal recessive albinism. METHODS: Mutation analysis using dHPLC or direct DNA sequencing of TYR, OCA2, TYRP1, and MATP was performed in 62 patients....... Two mutations in one OCA gene explained oculocutaneous albinism (OCA) in 44% of the patients. Mutations in TYR were found in 26% of patients, while OCA2 and MATP caused OCA in 15% and 3%, respectively. No mutations were found in TYRP1. Of the remaining 56% of patients, 29% were heterozygous...... recessive ocular albinism (AROA) based on clinical findings was 55 to 45. CONCLUSIONS: TYR is the major OCA gene in Denmark, but several patients do not have mutations in the investigated genes. A relatively large fraction of patients were observed with AROA, and of those 52% had no mutations compared...

  4. Root anomalies and dentin dysplasia in autosomal recessive hyperphosphatemic familial tumoral calcinosis (HFTC)

    Science.gov (United States)

    Vieira, Alexandre R.; Lee, Moses; Vairo, Filippo; Leite, Julio Cesar Loguercio; Munerato, Maria Cristina; Visioli, Fernanda; D’Ávila, Stéphanie Rodrigues; Wang, Shih-Kai; Choi, Murim; Simmer, James P.; Hu, Jan C-C.

    2015-01-01

    Hyperphosphatemic familial tumoral calcinosis (HFTC, OMIM #211900) is an autosomal recessive metabolic disorder characterized by hyperphosphatemia, tooth root defects, and the progressive deposition of calcium phosphate crystals in periarticular spaces, soft tissues, and sometimes bone.1 In this HFTC case report, we document the dental phenotype associated with a homozygous missense mutation (g.29077 C>T; c.484 C>T; p.Arg162*) in GALNT3 (OMIM 6017563), a gene encoding UDP-GalNAc transferase 3 that catalyzes the first step of O-linked oligosaccharide biosynthesis in the Golgi. The medical and dental pathology is believed to be caused primarily by high serum phosphate levels (hyperphosphatemia), which, in turn, is caused by failure of GALNT3 to glycosylate the phosphate regulator protein FGF23, impairing its ability inhibit reabsorption of filtered phosphate in the kidneys. PMID:26337219

  5. [Autosomal recessive polycystic kidney disease and complex nephronophtisis medullary cystic disease].

    Science.gov (United States)

    2008-12-01

    Reseach during the past decade has led to the discovery that defects in some proteins that localize to primary cilia or the basal body are the main contributors to renal cyst development. Autosomal recessive polycystic disease and nephronophthisis- medullary cystic kidney disease are named ciliopathies. The cilium is a microtubule-based organelle that is found on most mammalian cells. Cilia-mediated hypothesis has evolved into the concept of cystogenesis, cilia bend by fluid initiate a calcium influx that prevents cyst formation. Cilia might sense stimuli in the cell enviroment and control cell polarity and mitosis. A new set of pathogenic mechanisms in renal cystic disease defined new therapeutic targets, control of intracellular calcium, inhibition of cAMP and down regulation cannonical Wnt signaling.

  6. A homozygous mutation in TRIM36 causes autosomal recessive anencephaly in an Indian family.

    Science.gov (United States)

    Singh, Nivedita; Kumble Bhat, Vishwanath; Tiwari, Ankana; Kodaganur, Srinivas G; Tontanahal, Sagar J; Sarda, Astha; Malini, K V; Kumar, Arun

    2017-01-13

    Anencephaly is characterized by the absence of brain tissues and cranium. During primary neurulation stage of the embryo, the rostral part of the neural pore fails to close, leading to anencephaly. Anencephaly shows a heterogeneous etiology, ranging from environmental to genetic causes. The autosomal recessive inheritance of anencephaly has been reported in several populations. In this study, we employed whole-exome sequencing and identified a homozygous missense mutation c.1522C>A (p.Pro508Thr) in the TRIM36 gene as the cause of autosomal recessive anencephaly (APH) in an Indian family. The TRIM36 gene is expressed in the developing brain, suggesting a role in neurogenesis. In silco analysis showed that proline at codon position 508 is highly conserved in 26 vertebrate species, and the mutation is predicted to affect the conformation of the B30.2/SPRY domain of TRIM36. Both in vitro and in vivo results showed that the mutation renders the TRIM36 protein less stable. TRIM36 is known to associate with microtubules. Transient expression of the mutant TRIM36 in HeLa and LN229 cells resulted in microtubule disruption, disorganized spindles, loosely arranged chromosomes, multiple spindles, abnormal cytokinesis, reduced cell proliferation and increased apoptosis as compared to cells transfected with its wild-type counterpart. The siRNA knock down of TRIM36 in HeLa and LN229 cells also led to reduced cell proliferation and increased apoptosis. We suggest that microtubule disruption and disorganized spindles mediated by mutant TRIM36 affect neural cell proliferation during neural tube formation, leading to anencephaly.

  7. ABCA4 gene analysis in patients with autosomal recessive cone and cone rod dystrophies.

    Science.gov (United States)

    Kitiratschky, Veronique B D; Grau, Tanja; Bernd, Antje; Zrenner, Eberhart; Jägle, Herbert; Renner, Agnes B; Kellner, Ulrich; Rudolph, Günther; Jacobson, Samuel G; Cideciyan, Artur V; Schaich, Simone; Kohl, Susanne; Wissinger, Bernd

    2008-07-01

    The ATP-binding cassette (ABC) transporters constitute a family of large membrane proteins, which transport a variety of substrates across membranes. The ABCA4 protein is expressed in photoreceptors and possibly functions as a transporter for N-retinylidene-phosphatidylethanolamine (N-retinylidene-PE), the Schiff base adduct of all-trans-retinal with PE. Mutations in the ABCA4 gene have been initially associated with autosomal recessive Stargardt disease. Subsequent studies have shown that mutations in ABCA4 can also cause a variety of other retinal dystrophies including cone rod dystrophy and retinitis pigmentosa. To determine the prevalence and mutation spectrum of ABCA4 gene mutations in non-Stargardt phenotypes, we have screened 64 unrelated patients with autosomal recessive cone (arCD) and cone rod dystrophy (arCRD) applying the Asper Ophthalmics ABCR400 microarray followed by DNA sequencing of all coding exons of the ABCA4 gene in subjects with single heterozygous mutations. Disease-associated ABCA4 alleles were identified in 20 of 64 patients with arCD or arCRD. In four of 64 patients (6%) only one mutant ABCA4 allele was detected and in 16 patients (25%), mutations on both ABCA4 alleles were identified. Based on these data we estimate a prevalence of 31% for ABCA4 mutations in arCD and arCRD, supporting the concept that the ABCA4 gene is a major locus for various types of degenerative retinal diseases with abnormalities in cone or both cone and rod function.

  8. Homozygosity Mapping in Leber Congenital Amaurosis and Autosomal Recessive Retinitis Pigmentosa in South Indian Families.

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    Sundaramurthy Srilekha

    Full Text Available Leber congenital amaurosis (LCA and retinitis pigmentosa (RP are retinal degenerative diseases which cause severe retinal dystrophy affecting the photoreceptors. LCA is predominantly inherited as an autosomal recessive trait and contributes to 5% of all retinal dystrophies; whereas RP is inherited by all the Mendelian pattern of inheritance and both are leading causes of visual impairment in children and young adults. Homozygosity mapping is an efficient strategy for mapping both known and novel disease loci in recessive conditions, especially in a consanguineous mating, exploiting the fact that the regions adjacent to the disease locus will also be homozygous by descent in such inbred children. Here we have studied eleven consanguineous LCA and one autosomal recessive RP (arRP south Indian families to know the prevalence of mutations in known genes and also to know the involvement of novel loci, if any. Complete ophthalmic examination was done for all the affected individuals including electroretinogram, fundus photograph, fundus autofluorescence, and optical coherence tomography. Homozygosity mapping using Affymetrix 250K HMA GeneChip on eleven LCA families followed by screening of candidate gene(s in the homozygous block identified mutations in ten families; AIPL1 - 3 families, RPE65- 2 families, GUCY2D, CRB1, RDH12, IQCB1 and SPATA7 in one family each, respectively. Six of the ten (60% mutations identified are novel. Homozygosity mapping using Affymetrix 10K HMA GeneChip on the arRP family identified a novel nonsense mutation in MERTK. The mutations segregated within the family and was absent in 200 control chromosomes screened. In one of the eleven LCA families, the causative gene/mutation was not identified but many homozygous blocks were noted indicating that a possible novel locus/gene might be involved. The genotype and phenotype features, especially the fundus changes for AIPL1, RPE65, CRB1, RDH12 genes were as reported earlier.

  9. Autosomal recessive PGM3 mutations link glycosylation defects to atopy, immune deficiency, autoimmunity, and neurocognitive impairment

    Science.gov (United States)

    Zhang, Yu; Yu, Xiaomin; Ichikawa, Mie; Lyons, Jonathan J.; Datta, Shrimati; Lamborn, Ian T.; Jing, Huie; Kim, Emily S.; Biancalana, Matthew; Wolfe, Lynne A.; DiMaggio, Thomas; Matthews, Helen F.; Kranick, Sarah M.; Stone, Kelly D.; Holland, Steven M.; Reich, Daniel S.; Hughes, Jason D.; Mehmet, Huseyin; McElwee, Joshua; Freeman, Alexandra F.; Freeze, Hudson H.; Su, Helen C.; Milner, Joshua D.

    2014-01-01

    Background Identifying genetic syndromes that lead to significant atopic disease can open new pathways for investigation and intervention in allergy. Objective To define a genetic syndrome of severe atopy, elevated serum IgE, immune deficiency, autoimmunity, and motor and neurocognitive impairment. Methods Eight patients from two families who had similar syndromic features were studied. Thorough clinical evaluations, including brain MRI and sensory evoked potentials, were performed. Peripheral lymphocyte flow cytometry, antibody responses, and T cell cytokine production were measured. Whole exome sequencing was performed to identify disease-causing mutations. Immunoblotting, qRT-PCR, enzymatic assays, nucleotide sugar and sugar phosphate analyses along with MALDI-TOF mass spectrometry of glycans were used to determine the molecular consequences of the mutations. Results Marked atopy and autoimmunity were associated with increased TH2 and TH17 cytokine production by CD4+ T cells. Bacterial and viral infection susceptibility were noted along with T cell lymphopenia, particularly of CD8+ T cells, and reduced memory B cells. Apparent brain hypomyelination resulted in markedly delayed evoked potentials and likely contributed to neurological abnormalities. Disease segregated with novel autosomal recessive mutations in a single gene, phosphoglucomutase 3 (PGM3). Although PGM3 protein expression was variably diminished, impaired function was demonstrated by decreased enzyme activity and reduced UDP-GlcNAc, along with decreased O- and N-linked protein glycosylation in patients’ cells. These results define a new Congenital Disorder of Glycosylation. Conclusions Autosomal recessive, hypomorphic PGM3 mutations underlie a disorder of severe atopy, immune deficiency, autoimmunity, intellectual disability and hypomyelination. PMID:24589341

  10. Homozygous mutations in IHH cause acrocapitofemoral dysplasia, an autosomal recessive disorder with cone- shaped epiphyses in hands and hips

    NARCIS (Netherlands)

    Hellemans, J; Coucke, PJ; Giedion, A; De Paepe, A; Kramer, P; Beemer, F; Mortier, GR

    2003-01-01

    Acrocapitofemoral dysplasia is a recently delineated autosomal recessive skeletal dysplasia, characterized clinically by short stature with short limbs and radiographically by cone-shaped epiphyses, mainly in hands and hips. Genome-wide homozygosity mapping in two consanguineous families linked the

  11. Autozygosity mapping of a large consanguineous Pakistani family reveals a novel non-syndromic autosomal recessive mental retardation locus on 11p15-tel

    DEFF Research Database (Denmark)

    Rehman, Shoaib ur; Baig, Shahid Mahmood; Eiberg, Hans;

    2011-01-01

    Autosomal recessive inherited mental retardation is an extremely heterogeneous disease and accounts for approximately 25% of all non-syndromic mental retardation cases. Autozygosity mapping of a large consanguineous Pakistani family revealed a novel locus for non-syndromic autosomal recessive men...

  12. Autosomal recessive hypophosphataemic rickets with hypercalciuria is not caused by mutations in the type II renal sodium/phosphate cotransporter gene.

    NARCIS (Netherlands)

    Heuvel, L.P.W.J. van den; Koul, K. Op de; Knots, E.; Knoers, N.V.A.M.; Monnens, L.A.H.

    2001-01-01

    BACKGROUND: At present the genetic defect for autosomal recessive and autosomal dominant hypophosphataemic rickets with hypercalciuria (HHRH) is unknown. Type II sodium/phosphate cotransporter (NPT2) gene is a serious candidate for being the causative gene in either or both autosomal recessive and a

  13. An intronic deletion in the PROM1 gene leads to autosomal recessive cone-rod dystrophy

    Science.gov (United States)

    Eidinger, Osnat; Leibu, Rina; Newman, Hadas; Rizel, Leah; Perlman, Ido

    2015-01-01

    Purpose To investigate the genetic basis for autosomal recessive cone-rod dystrophy (CRD) in a consanguineous Israeli Jewish family. Methods Patients underwent a detailed ophthalmic evaluation, including eye examination, visual field testing, optical coherence tomography (OCT), and electrophysiological tests, electroretinography (ERG) and visual evoked potential (VEP). Genome-wide homozygosity mapping using a single nucleotide polymorphism (SNP) array was performed to identify homozygous regions shared among two of the affected individuals. Mutation screening of the underlying gene was performed with direct sequencing. In silico and in vitro analyses were used to predict the effect of the identified mutation on splicing. Results The affected family members are three siblings who have various degrees of progressive visual deterioration, glare, color vision abnormalities, and night vision difficulties. Visual field tests revealed central scotomas of different extension. Cone and rod ERG responses were reduced, with cones more severely affected. Homozygosity mapping revealed several homozygous intervals shared among two of the affected individuals. One included the PROM1 gene. Sequence analysis of the 26 coding exons of PROM1 in one affected individual revealed no mutations in the coding sequence or in intronic splice sites. However, in intron 21, proximate to the intron–exon junction, we observed a homozygous 10 bp deletion between positions −26 and −17 (c.2281–26_-17del). The deletion was linked to a known SNP, c.2281–6C>G. The deletion cosegregated with the disease in the family, and was not detected in public databases or in 101 ethnically-matched control individuals. In silico analysis predicted that this deletion would lead to altered intron 21 splicing. Bioinformatic analysis predicted that a recognition site for the SRSF2 splicing factor is located within the deleted sequence. The in vitro splicing assay demonstrated that c.2281–26_-17del leads to

  14. Mutation in LIM2 Is Responsible for Autosomal Recessive Congenital Cataracts

    Science.gov (United States)

    Irum, Bushra; Khan, Shahid Y.; Ali, Muhammad; Kaul, Haiba; Kabir, Firoz; Rauf, Bushra; Fatima, Fareeha; Nadeem, Raheela; Khan, Arif O.; Al Obaisi, Saif; Naeem, Muhammad Asif; Nasir, Idrees A.; Khan, Shaheen N.; Husnain, Tayyab; Riazuddin, Sheikh; Akram, Javed; Eghrari, Allen O.; Riazuddin, S. Amer

    2016-01-01

    Purpose To identify the molecular basis of non-syndromic autosomal recessive congenital cataracts (arCC) in a consanguineous family. Methods All family members participating in the study received a comprehensive ophthalmic examination to determine their ocular phenotype and contributed a blood sample, from which genomic DNA was extracted. Available medical records and interviews with the family were used to compile the medical history of the family. The symptomatic history of the individuals exhibiting cataracts was confirmed by slit-lamp biomicroscopy. A genome-wide linkage analysis was performed to localize the disease interval. The candidate gene, LIM2 (lens intrinsic membrane protein 2), was sequenced bi-directionally to identify the disease-causing mutation. The physical changes caused by the mutation were analyzed in silico through homology modeling, mutation and bioinformatic algorithms, and evolutionary conservation databases. The physiological importance of LIM2 to ocular development was assessed in vivo by real-time expression analysis of Lim2 in a mouse model. Results Ophthalmic examination confirmed the diagnosis of nuclear cataracts in the affected members of the family; the inheritance pattern and cataract development in early infancy indicated arCC. Genome-wide linkage analysis localized the critical interval to chromosome 19q with a two-point logarithm of odds (LOD) score of 3.25. Bidirectional sequencing identified a novel missense mutation, c.233G>A (p.G78D) in LIM2. This mutation segregated with the disease phenotype and was absent in 192 ethnically matched control chromosomes. In silico analysis predicted lower hydropathicity and hydrophobicity but higher polarity of the mutant LIM2-encoded protein (MP19) compared to the wild-type. Moreover, these analyses predicted that the mutation would disrupt the secondary structure of a transmembrane domain of MP19. The expression of Lim2, which was detected in the mouse lens as early as embryonic day 15

  15. A pedigree-analysis approach to the descriptive epidemiology of autosomal-recessive disorders.

    Science.gov (United States)

    Man, W Y N; Nicholas, F W; James, J W

    2007-03-17

    We describe a pedigree-analysis approach to estimating descriptive epidemiological parameters for autosomal-recessive disorders when the ancestral source of the disorder is known. We show that the expected frequency of carriers in a cohort equals the gene contribution of the ancestral source to that cohort, which is equivalent to the direct (additive) genetic relationship of that ancestor to the cohort. Also, the expected incidence of affected foetuses ranges from (1/2)F* to F*, where F* is the mean partial inbreeding coefficient (due to the ancestor) of the cohort. We applied this approach to complex vertebral malformation (CVM) in Holstein-Friesians in Australia, for which the ancestral source is a USA-born bull, Carlin-M Ivanhoe Bell. The estimated frequency of carriers was 2.47% for the 1992-born and 4.44% for the 1997-born cohort of Holstein-Friesian cows in Australia. The estimated incidence of affected foetuses/calves was considerably less than one per thousand, ranging from 0.0024 to 0.0048% for the 1992-born cohort, and from 0.0288 to 0.0576% for the 1997-born cohort. These incidences correspond to expected numbers of affected female foetuses/calves ranging from 2 to 4 for the 1992-born cohort and from 28 to 56 for the 1997-born cohort. This approach is easy to implement using software that is readily available.

  16. Successful twin pregnancy in a patient with parkin-associated autosomal recessive juvenile parkinsonism

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    Takakuwa Koichi

    2011-06-01

    Full Text Available Abstract Background Pregnancy in patients with Parkinson disease is a rare occurrence. To the best of our knowledge, the effect of pregnancy as well as treatment in genetically confirmed autosomal recessive juvenile parkinsonism (ARJP has never been reported. Here, we report the first case of pregnancy in a patient with ARJP associated with a parkin gene mutation, ARJP/PARK2. Case presentation A 27-year-old woman with ARJP/PARK2 was diagnosed as having a spontaneous dichorionic/diamniotic twin pregnancy. Exacerbation of motor disability was noted between ovulation and menstruation before pregnancy as well as during late pregnancy, suggesting that her parkinsonism might have been influenced by fluctuations in the levels of endogenous sex hormones. During the organogenesis period, she was only treated with levodopa/carbidopa, although she continued to receive inpatient hospital care for assistance in the activities of daily living. After the organogenesis period, she was administered sufficient amounts of antiparkinsonian drugs. She delivered healthy male twins, and psychomotor development of both the babies was normal at the age of 2 years. Conclusion Pregnancy may worsen the symptoms of ARJP/PARK2, although appropriate treatments with antiparkinsonian drugs and adequate assistance in the activities of daily living might enable successful pregnancy and birth of healthy children.

  17. Mutations in Transglutaminase 1 Gene in Autosomal Recessive Congenital Ichthyosis in Egyptian Families

    Directory of Open Access Journals (Sweden)

    R. M. Shawky

    2004-01-01

    Full Text Available Autosomal recessive congenital ichthyosis (ARCI is a rare heterogeneous keratinization disorder of the skin. It is clinically divided into 2 subtypes, lamellar ichthyosis (LI and congenital ichthyosiformis erythroderma (CIE. We investigated forty-three ARCI Egyptian individuals in 16 severe LI, and 10 CIE families. We identified 5 alleles in two Egyptian families as having intron-5/exon-6 splice acceptor mutation recognized by the MspI restriction endonuclease. This promoted to a frequency of 9.6% for this mutation (5 splice-mutation alleles/52 alleles tested. We extended our previous dataset to update the detection of R142H mutation in 4 CIE Egyptian families and one LI phenotype (frequency of 28.8%; 15/52, whereas we still had no R141H among our Egyptian population. There was no correlation between phenotype and genotype in our study. Surprisingly, the mutant alleles detected in intron-5 acceptor splice-site were associated with the other extreme of CIE phenotypes rather than the severe LI form. We clearly demonstrated that the ARCI Egyptian families in Upper Egypt was ethnically pure and had a tendency not to be a hybrid with other populations in Lower Egypt, Delta zone and Cairo city.

  18. Development of novel noninvasive prenatal testing protocol for whole autosomal recessive disease using picodroplet digital PCR

    Science.gov (United States)

    Chang, Mun Young; Kim, Ah Reum; Kim, Min Young; Kim, Soyoung; Yoon, Jinsun; Han, Jae Joon; Ahn, Soyeon; Kang, Changsoo; Choi, Byung Yoon

    2016-01-01

    We developed a protocol of noninvasive prenatal testing (NIPT), employing a higher-resolution picodroplet digital PCR, to detect genetic imbalance in maternal plasma DNA (mpDNA) caused by cell-free fetal DNA (cffDNA). In the present study, this approach was applied to four families with autosomal recessive (AR) congenital sensorineural hearing loss. First, a fraction of the fetal DNA in mpDNA was calculated. Then, we made artificial DNA mixtures (positive and negative controls) to simulate mpDNA containing the fraction of cffDNA with or without mutations. Next, a fraction of mutant cluster signals over the total signals was measured from mpDNA, positive controls, and negative controls. We determined whether fetal DNA carried any paternal or maternal mutations by calculating and comparing the sum of the log-likelihood of the study samples. Of the four families, we made a successful prediction of the complete fetal genotype in two cases where a distinct cluster was identified for each genotype and the fraction of cffDNA in mpDNA was at least 6.4%. Genotyping of only paternal mutation was possible in one of the other two families. This is the first NIPT protocol potentially applicable to any AR monogenic disease with various genotypes, including point mutations. PMID:27924908

  19. Panel-based NGS Reveals Novel Pathogenic Mutations in Autosomal Recessive Retinitis Pigmentosa.

    Science.gov (United States)

    Perez-Carro, Raquel; Corton, Marta; Sánchez-Navarro, Iker; Zurita, Olga; Sanchez-Bolivar, Noelia; Sánchez-Alcudia, Rocío; Lelieveld, Stefan H; Aller, Elena; Lopez-Martinez, Miguel Angel; López-Molina, Ma Isabel; Fernandez-San Jose, Patricia; Blanco-Kelly, Fiona; Riveiro-Alvarez, Rosa; Gilissen, Christian; Millan, Jose M; Avila-Fernandez, Almudena; Ayuso, Carmen

    2016-01-25

    Retinitis pigmentosa (RP) is a group of inherited progressive retinal dystrophies (RD) characterized by photoreceptor degeneration. RP is highly heterogeneous both clinically and genetically, which complicates the identification of causative genes and mutations. Targeted next-generation sequencing (NGS) has been demonstrated to be an effective strategy for the detection of mutations in RP. In our study, an in-house gene panel comprising 75 known RP genes was used to analyze a cohort of 47 unrelated Spanish families pre-classified as autosomal recessive or isolated RP. Disease-causing mutations were found in 27 out of 47 cases achieving a mutation detection rate of 57.4%. In total, 33 pathogenic mutations were identified, 20 of which were novel mutations (60.6%). Furthermore, not only single nucleotide variations but also copy-number variations, including three large deletions in the USH2A and EYS genes, were identified. Finally seven out of 27 families, displaying mutations in the ABCA4, RP1, RP2 and USH2A genes, could be genetically or clinically reclassified. These results demonstrate the potential of our panel-based NGS strategy in RP diagnosis.

  20. The renin-angiotensin system and hypertension in autosomal recessive polycystic kidney disease.

    Science.gov (United States)

    Goto, Miwa; Hoxha, Nita; Osman, Rania; Dell, Katherine Macrae

    2010-12-01

    Hypertension is a well-recognized complication of autosomal recessive polycystic kidney disease (ARPKD). The renin-angiotensin system (RAS) is a key regulator of blood pressure; however, data on the RAS in ARPKD are limited and conflicting, showing both up- and down-regulation. In the current study, we characterized intrarenal and systemic RAS activation in relationship to hypertension and progressive cystic kidney disease in the ARPKD orthologous polycystic kidney (PCK) rat. Clinical and histological measures of kidney disease, kidney RAS gene expression by quantitative real-time PCR, angiotensin II (Ang II) immunohistochemistry, and systemic Ang I and II levels were assessed in 2-, 4-, and 6-month-old cystic PCK and age-matched normal rats. PCK rats developed hypertension and progressive cystic kidney disease without significant worsening of renal function or relative kidney size. Intrarenal renin, ACE and Ang II expression was increased significantly in cystic kidneys; angiotensinogen and Ang II Type I receptor were unchanged. Systemic Ang I and II levels did not differ. This study demonstrates that intrarenal, but not systemic, RAS activation is a prominent feature of ARPKD. These findings help reconcile previous conflicting reports and suggest that intrarenal renin and ACE gene upregulation may represent a novel mechanism for hypertension development or exacerbation in ARPKD.

  1. Autosomal recessive mental retardation syndrome with anterior maxillary protrusion and strabismus: MRAMS syndrome.

    Science.gov (United States)

    Basel-Vanagaite, Lina; Rainshtein, Limor; Inbar, Dov; Gothelf, Doron; Hennekam, Raoul; Straussberg, Rachel

    2007-08-01

    We report on a family in whom the combination of mental retardation (MR), anterior maxillary protrusion, and strabismus segregates. The healthy, consanguineous parents (first cousins) of Israeli-Arab descent had 11 children, 7 of whom (5 girls) were affected. They all had severe MR. Six of the seven had anterior maxillary protrusion with vertical maxillary excess, open bite, and prominent crowded teeth. None of the sibs with normal intelligence had jaw or dental anomalies. The child with MR but without a jaw anomaly was somewhat less severely retarded, had seizures and severe psychosis, which may point to his having a separate disorder. Biochemical and neurological studies, including brain MRI and standard cytogenetic studies, yielded normal results; fragile X was excluded, no subtelomeric rearrangements were detectable, and X-inactivation studies in the mother showed random inactivation. We have been unable to find a similar disorder in the literature, and suggest that this is a hitherto unreported autosomal recessive disorder, which we propose to name MRAMS (mental retardation, anterior maxillary protrusion, and strabismus).

  2. Where do we stand in trial readiness for autosomal recessive limb girdle muscular dystrophies?

    Science.gov (United States)

    Straub, Volker; Bertoli, Marta

    2016-02-01

    Autosomal recessive limb girdle muscular dystrophies (LGMD2) are a group of genetically heterogeneous diseases that are typically characterised by progressive weakness and wasting of the shoulder and pelvic girdle muscles. Many of the more than 20 different conditions show overlapping clinical features with other forms of muscular dystrophy, congenital, myofibrillar or even distal myopathies and also with acquired muscle diseases. Although individually extremely rare, all types of LGMD2 together form an important differential diagnostic group among neuromuscular diseases. Despite improved diagnostics and pathomechanistic insight, a curative therapy is currently lacking for any of these diseases. Medical care consists of the symptomatic treatment of complications, aiming to improve life expectancy and quality of life. Besides well characterised pre-clinical tools like animal models and cell culture assays, the determinants of successful drug development programmes for rare diseases include a good understanding of the phenotype and natural history of the disease, the existence of clinically relevant outcome measures, guidance on care standards, up to date patient registries, and, ideally, biomarkers that can help assess disease severity or drug response. Strong patient organisations driving research and successful partnerships between academia, advocacy, industry and regulatory authorities can also help accelerate the elaboration of clinical trials. All these determinants constitute aspects of translational research efforts and influence patient access to therapies. Here we review the current status of determinants of successful drug development programmes for LGMD2, and the challenges of translating promising therapeutic strategies into effective and accessible treatments for patients.

  3. Mutation Spectrum of EYS in Spanish Patients with Autosomal Recessive Retinitis Pigmentosa

    Science.gov (United States)

    Barragán, Isabel; Borrego, Salud; Pieras, Juan Ignacio; Pozo, María González-del; Santoyo, Javier; Ayuso, Carmen; Baiget, Montserrat; Millan, José M; Mena, Marcela; El-Aziz, Mai M Abd; Audo, Isabelle; Zeitz, Christina; Littink, Karin W; Dopazo, Joaquín; Bhattacharya, Shomi S; Antiñolo, Guillermo

    2010-01-01

    Retinitis pigmentosa (RP) is a heterogeneous group of inherited retinal dystrophies characterised ultimately by the loss of photoreceptor cells. We have recently identified a new gene (EYS) encoding an ortholog of Drosophila spacemaker (spam) as a commonly mutated gene in autosomal recessive RP. In the present study, we report the identification of 73 sequence variations in EYS, of which 28 are novel. Of these, 42.9% (12/28) are very likely pathogenic, 17.9% (5/28) are possibly pathogenic, whereas 39.3% (11/28) are SNPs. In addition, we have detected 3 pathogenic changes previously reported in other populations. We are also presenting the characterisation of EYS homologues in different species, and a detailed analysis of the EYS domains, with the identification of an interesting novel feature: a putative coiled-coil domain. Majority of the mutations in the arRP patients have been found within the domain structures of EYS. The minimum observed prevalence of distinct EYS mutations in our group of patients is of 15.9% (15/94), confirming a major involvement of EYS in the pathogenesis of arRP in the Spanish population. Along with the detection of three recurrent mutations in Caucasian population, our hypothesis of EYS being the first prevalent gene in arRP has been reinforced in the present study. © 2010 Wiley-Liss, Inc. PMID:21069908

  4. Libyan Boy with Autosomal Recessive Trait (P22-phox Defect of Chronic Granulomatous Disease

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    Ilka Schulze

    2006-09-01

    Full Text Available Chronic granulomatous disease (CGD is a primary immune deficiency disorder of the phagocytes. In this disorder, phagocytic cells (polymorphonuclear leukocytes and monocytes cannot produce active oxygen metabolites, and therefore, cannot destroy the ingested intracellular bacteria. Clinically, patients with CGD usually have recurrent bacterial and fungal infections causing abscess and granuloma formation in the skin, lymph nodes and visceral organs.In this report, we present a boy from Libya with a rare autosomal recessive trait of CGD (defect of p22-phox who has chronic lung disease following multiple severe pneumonia attacks. The case we present suffered from bloody diarrhea since the third month of his life. He also had recurrent episodes of fever, and later, developed persistent cervical lymphadenitis and failure to gain weight. CGD is a very rare condition worldwide. It is also not recognized here in Libya, and usually not in the list of differential diagnosis for chronic pulmonary infections. We advise that pediatricians and general practitioners who treat chronic cases of lung diseases (with or without chronic diarrhea should consider primary immunodeficiency disorders in the hope that early diagnosis and treatment may prevent chronic complications especially of the respiratory tract. Furthermore, we state that, to the best of our knowledge, this is the first documented case of CGD from Libya.

  5. The molecular basis of autosomal recessive diseases among the Arabs and Druze in Israel.

    Science.gov (United States)

    Zlotogora, Joël

    2010-11-01

    The Israeli population mainly includes Jews, Muslim and Christian Arabs, and Druze In the last decade, data on genetic diseases present in the population have been systematically collected and are available online in the Israeli national genetic database ( http://www.goldenhelix.org/server/israeli ). In the non-Jewish population, up to 1 July 2010, the database included molecular data on six diseases relatively frequent in the whole population: thalassemia, familial Mediterranean fever (FMF), cystic fibrosis, deafness, phenylketonuria and congenital adrenal hyperplasia, as well as data on 195 autosomal recessive diseases among Muslim Israeli Arabs, 11 among the Christian Arabs and 31 among Druze. A single mutation was characterized in 149 out of the 238 rare disorders for which the molecular basis was known. In many diseases, mutation had never been observed in any other population and was present in one family only suggesting that it occurred as a de novo event. In other diseases, the mutation was present in more than one community or even in other populations such as Bedouins from the Arab peninsula or Christians from Lebanon. In the 89 other disorders, more than one mutation was characterized either in the same gene or in more than one gene. While it is probable that most of these cases represent random events in some cases such as Bardet Biedl among the Bedouins, the reason may be a selective advantage to the heterozygotes.

  6. A novel deletion mutation in the TUSC3 gene in a consanguineous Pakistani family with autosomal recessive nonsyndromic intellectual disability

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    Ali Nadir

    2011-04-01

    Full Text Available Abstract Background Intellectual disability (ID is a serious disorder of the central nervous system with a prevalence of 1-3% in a general population. In the past decades, the research focus has been predominantly on X-linked ID (68 loci and 19 genes for non syndromic X linked ID while for autosomal recessive nonsyndromic ID (NSID only 30 loci and 6 genes have been reported to date. Methods Genome-wide homozygosity mapping with 500 K Nsp1 array (Affymetrix, CNV analysis, PCR based breakpoint mapping and DNA sequencing was performed to explore the genetic basis of autosomal recessive nonsyndromic ID in a large Pakistani family. Results Data analysis showed linkage at 8p23 locus with common homozygous region between SNPs rs6989820 and rs2237834, spanning a region of 12.494 Mb. The subsequent CNV analysis of the data revealed a homozygous deletion of 170.673 Kb which encompassed the TUSC3 gene. Conclusion We report a novel deletion mutation in TUSC3 gene which is the second gene after TRAPPC9 in which mutation has been identified in more than one family with autosomal recessive NSID. The study will aid in exploring the molecular pathway of cognition.

  7. Proof-of-principle rapid noninvasive prenatal diagnosis of autosomal recessive founder mutations

    Science.gov (United States)

    Zeevi, David A.; Altarescu, Gheona; Weinberg-Shukron, Ariella; Zahdeh, Fouad; Dinur, Tama; Chicco, Gaya; Herskovitz, Yair; Renbaum, Paul; Elstein, Deborah; Levy-Lahad, Ephrat; Rolfs, Arndt; Zimran, Ari

    2015-01-01

    BACKGROUND. Noninvasive prenatal testing can be used to accurately detect chromosomal aneuploidies in circulating fetal DNA; however, the necessity of parental haplotype construction is a primary drawback to noninvasive prenatal diagnosis (NIPD) of monogenic disease. Family-specific haplotype assembly is essential for accurate diagnosis of minuscule amounts of circulating cell-free fetal DNA; however, current haplotyping techniques are too time-consuming and laborious to be carried out within the limited time constraints of prenatal testing, hampering practical application of NIPD in the clinic. Here, we have addressed this pitfall and devised a universal strategy for rapid NIPD of a prevalent mutation in the Ashkenazi Jewish (AJ) population. METHODS. Pregnant AJ couples, carrying mutation(s) in GBA, which encodes acid β-glucosidase, were recruited at the SZMC Gaucher Clinic. Targeted next-generation sequencing of GBA-flanking SNPs was performed on peripheral blood samples from each couple, relevant mutation carrier family members, and unrelated individuals who are homozygotes for an AJ founder mutation. Allele-specific haplotypes were constructed based on linkage, and a consensus Gaucher disease–associated founder mutation–flanking haplotype was fine mapped. Together, these haplotypes were used for NIPD. All test results were validated by conventional prenatal or postnatal diagnostic methods. RESULTS. Ten parental alleles in eight unrelated fetuses were diagnosed successfully based on the noninvasive method developed in this study. The consensus mutation–flanking haplotype aided diagnosis for 6 of 9 founder mutation alleles. CONCLUSIONS. The founder NIPD method developed and described here is rapid, economical, and readily adaptable for prenatal testing of prevalent autosomal recessive disease-causing mutations in an assortment of worldwide populations. FUNDING. SZMC, Protalix Biotherapeutics Inc., and Centogene AG. PMID:26426075

  8. Brain Connectivity Changes in Autosomal Recessive Parkinson Disease: A Model for the Sporadic Form

    Science.gov (United States)

    Makovac, Elena; Cercignani, Mara; Serra, Laura; Torso, Mario; Spanò, Barbara; Petrucci, Simona; Ricciardi, Lucia; Ginevrino, Monia; Caltagirone, Carlo; Bentivoglio, Anna Rita; Valente, Enza Maria; Bozzali, Marco

    2016-01-01

    Biallelic genetic mutations in the Park2 and PINK1 genes are frequent causes of autosomal recessive PD. Carriers of single heterozygous mutations may manifest subtle signs of disease, thus providing a unique model of preclinical PD. One emerging hypothesis suggests that non-motor symptom of PD, such as cognitive impairment may be due to a distributed functional disruption of various neuronal circuits. Using resting-state functional MRI (RS-fMRI), we tested the hypothesis that abnormal connectivity within and between brain networks may account for the patients’ cognitive status. Eight homozygous and 12 heterozygous carriers of either PINK1 or Park2 mutation and 22 healthy controls underwent RS-fMRI and cognitive assessment. RS-fMRI data underwent independent component analysis to identify five networks of interest: default-mode network, salience network, executive network, right and left fronto-parietal networks. Functional connectivity within and between each network was assessed and compared between groups. All mutation carriers were cognitively impaired, with the homozygous group reporting a more prominent impairment in visuo-spatial working memory. Changes in functional connectivity were evident within all networks between homozygous carriers and controls. Also heterozygotes reported areas of reduced connectivity when compared to controls within two networks. Additionally, increased inter-network connectivity was observed in both groups of mutation carriers, which correlated with their spatial working memory performance, and could thus be interpreted as compensatory. We conclude that both homozygous and heterozygous carriers exhibit pathophysiological changes unveiled by RS-fMRI, which can account for the presence/severity of cognitive symptoms. PMID:27788143

  9. Deletion at the GCNT2 Locus Causes Autosomal Recessive Congenital Cataracts

    Science.gov (United States)

    Irum, Bushra; Khan, Shahid Y.; Ali, Muhammad; Daud, Muhammad; Kabir, Firoz; Rauf, Bushra; Fatima, Fareeha; Iqbal, Hira; Khan, Arif O.; Al Obaisi, Saif; Naeem, Muhammad Asif; Nasir, Idrees A.; Khan, Shaheen N.; Husnain, Tayyab; Riazuddin, Sheikh; Akram, Javed; Eghrari, Allen O.; Riazuddin, S. Amer

    2016-01-01

    Purpose The aim of this study is to identify the molecular basis of autosomal recessive congenital cataracts (arCC) in a large consanguineous pedigree. Methods All participating individuals underwent a detailed ophthalmic examination. Each patient’s medical history, particularly of cataracts and other ocular abnormalities, was compiled from available medical records and interviews with family elders. Blood samples were donated by all participating family members and used to extract genomic DNA. Genetic analysis was performed to rule out linkage to known arCC loci and genes. Whole-exome sequencing libraries were prepared and paired-end sequenced. A large deletion was found that segregated with arCC in the family, and chromosome walking was conducted to estimate the proximal and distal boundaries of the deletion mutation. Results Exclusion and linkage analysis suggested linkage to a region of chromosome 6p24 harboring GCNT2 (glucosaminyl (N-acetyl) transferase 2) with a two-point logarithm of odds score of 5.78. PCR amplifications of the coding exons of GCNT2 failed in individuals with arCC, and whole-exome data analysis revealed a large deletion on chromosome 6p in the region harboring GCNT2. Chromosomal walking using multiple primer pairs delineated the extent of the deletion to approximately 190 kb. Interestingly, a failure to amplify a junctional fragment of the deletion break strongly suggests an insertion in addition to the large deletion. Conclusion Here, we report a novel insertion/deletion mutation at the GCNT2 locus that is responsible for congenital cataracts in a large consanguineous family. PMID:27936067

  10. A Founder Mutation in VPS11 Causes an Autosomal Recessive Leukoencephalopathy Linked to Autophagic Defects.

    Science.gov (United States)

    Zhang, Jinglan; Lachance, Véronik; Schaffner, Adam; Li, Xianting; Fedick, Anastasia; Kaye, Lauren E; Liao, Jun; Rosenfeld, Jill; Yachelevich, Naomi; Chu, Mary-Lynn; Mitchell, Wendy G; Boles, Richard G; Moran, Ellen; Tokita, Mari; Gorman, Elizabeth; Bagley, Kaytee; Zhang, Wei; Xia, Fan; Leduc, Magalie; Yang, Yaping; Eng, Christine; Wong, Lee-Jun; Schiffmann, Raphael; Diaz, George A; Kornreich, Ruth; Thummel, Ryan; Wasserstein, Melissa; Yue, Zhenyu; Edelmann, Lisa

    2016-04-01

    Genetic leukoencephalopathies (gLEs) are a group of heterogeneous disorders with white matter abnormalities affecting the central nervous system (CNS). The causative mutation in ~50% of gLEs is unknown. Using whole exome sequencing (WES), we identified homozygosity for a missense variant, VPS11: c.2536T>G (p.C846G), as the genetic cause of a leukoencephalopathy syndrome in five individuals from three unrelated Ashkenazi Jewish (AJ) families. All five patients exhibited highly concordant disease progression characterized by infantile onset leukoencephalopathy with brain white matter abnormalities, severe motor impairment, cortical blindness, intellectual disability, and seizures. The carrier frequency of the VPS11: c.2536T>G variant is 1:250 in the AJ population (n = 2,026). VPS11 protein is a core component of HOPS (homotypic fusion and protein sorting) and CORVET (class C core vacuole/endosome tethering) protein complexes involved in membrane trafficking and fusion of the lysosomes and endosomes. The cysteine 846 resides in an evolutionarily conserved cysteine-rich RING-H2 domain in carboxyl terminal regions of VPS11 proteins. Our data shows that the C846G mutation causes aberrant ubiquitination and accelerated turnover of VPS11 protein as well as compromised VPS11-VPS18 complex assembly, suggesting a loss of function in the mutant protein. Reduced VPS11 expression leads to an impaired autophagic activity in human cells. Importantly, zebrafish harboring a vps11 mutation with truncated RING-H2 domain demonstrated a significant reduction in CNS myelination following extensive neuronal death in the hindbrain and midbrain. Thus, our study reveals a defect in VPS11 as the underlying etiology for an autosomal recessive leukoencephalopathy disorder associated with a dysfunctional autophagy-lysosome trafficking pathway.

  11. A Founder Mutation in VPS11 Causes an Autosomal Recessive Leukoencephalopathy Linked to Autophagic Defects.

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    Jinglan Zhang

    2016-04-01

    Full Text Available Genetic leukoencephalopathies (gLEs are a group of heterogeneous disorders with white matter abnormalities affecting the central nervous system (CNS. The causative mutation in ~50% of gLEs is unknown. Using whole exome sequencing (WES, we identified homozygosity for a missense variant, VPS11: c.2536T>G (p.C846G, as the genetic cause of a leukoencephalopathy syndrome in five individuals from three unrelated Ashkenazi Jewish (AJ families. All five patients exhibited highly concordant disease progression characterized by infantile onset leukoencephalopathy with brain white matter abnormalities, severe motor impairment, cortical blindness, intellectual disability, and seizures. The carrier frequency of the VPS11: c.2536T>G variant is 1:250 in the AJ population (n = 2,026. VPS11 protein is a core component of HOPS (homotypic fusion and protein sorting and CORVET (class C core vacuole/endosome tethering protein complexes involved in membrane trafficking and fusion of the lysosomes and endosomes. The cysteine 846 resides in an evolutionarily conserved cysteine-rich RING-H2 domain in carboxyl terminal regions of VPS11 proteins. Our data shows that the C846G mutation causes aberrant ubiquitination and accelerated turnover of VPS11 protein as well as compromised VPS11-VPS18 complex assembly, suggesting a loss of function in the mutant protein. Reduced VPS11 expression leads to an impaired autophagic activity in human cells. Importantly, zebrafish harboring a vps11 mutation with truncated RING-H2 domain demonstrated a significant reduction in CNS myelination following extensive neuronal death in the hindbrain and midbrain. Thus, our study reveals a defect in VPS11 as the underlying etiology for an autosomal recessive leukoencephalopathy disorder associated with a dysfunctional autophagy-lysosome trafficking pathway.

  12. A Founder Mutation in VPS11 Causes an Autosomal Recessive Leukoencephalopathy Linked to Autophagic Defects

    Science.gov (United States)

    Schaffner, Adam; Fedick, Anastasia; Kaye, Lauren E.; Liao, Jun; Yachelevich, Naomi; Chu, Mary-Lynn; Boles, Richard G.; Moran, Ellen; Tokita, Mari; Gorman, Elizabeth; Zhang, Wei; Xia, Fan; Leduc, Magalie; Yang, Yaping; Eng, Christine; Wong, Lee-Jun; Schiffmann, Raphael; Diaz, George A.; Kornreich, Ruth; Thummel, Ryan; Wasserstein, Melissa; Yue, Zhenyu; Edelmann, Lisa

    2016-01-01

    Genetic leukoencephalopathies (gLEs) are a group of heterogeneous disorders with white matter abnormalities affecting the central nervous system (CNS). The causative mutation in ~50% of gLEs is unknown. Using whole exome sequencing (WES), we identified homozygosity for a missense variant, VPS11: c.2536T>G (p.C846G), as the genetic cause of a leukoencephalopathy syndrome in five individuals from three unrelated Ashkenazi Jewish (AJ) families. All five patients exhibited highly concordant disease progression characterized by infantile onset leukoencephalopathy with brain white matter abnormalities, severe motor impairment, cortical blindness, intellectual disability, and seizures. The carrier frequency of the VPS11: c.2536T>G variant is 1:250 in the AJ population (n = 2,026). VPS11 protein is a core component of HOPS (homotypic fusion and protein sorting) and CORVET (class C core vacuole/endosome tethering) protein complexes involved in membrane trafficking and fusion of the lysosomes and endosomes. The cysteine 846 resides in an evolutionarily conserved cysteine-rich RING-H2 domain in carboxyl terminal regions of VPS11 proteins. Our data shows that the C846G mutation causes aberrant ubiquitination and accelerated turnover of VPS11 protein as well as compromised VPS11-VPS18 complex assembly, suggesting a loss of function in the mutant protein. Reduced VPS11 expression leads to an impaired autophagic activity in human cells. Importantly, zebrafish harboring a vps11 mutation with truncated RING-H2 domain demonstrated a significant reduction in CNS myelination following extensive neuronal death in the hindbrain and midbrain. Thus, our study reveals a defect in VPS11 as the underlying etiology for an autosomal recessive leukoencephalopathy disorder associated with a dysfunctional autophagy-lysosome trafficking pathway. PMID:27120463

  13. A Register-Based Study of Diseases With an Autosomal Recessive Origin in Small Children in Denmark According to Maternal Country of Origin

    DEFF Research Database (Denmark)

    Gundlund, Anna; Hansen, Anne Vinkel; Pedersen, Grete Skøtt

    2015-01-01

    information on consanguinity is lacking, this suggestion is difficult to test. With an indirect approach, we addressed this question by comparing the risk of diseases with autosomal recessive inheritance in children born in Denmark of Danish-born women and of women born in these five countries, respectively....... METHODS: All children born in Denmark (1994-2010) were followed until 5 years of age or end-of-study period for the risk of hospitalisation with diseases of autosomal recessive aetiology, and therefore considered consanguinity-related. Diagnoses of autosomal recessive diseases were identified using two...... different methods: a literature review of consanguinity-associated diseases and a search in the Online Catalogue of Human Genes and Genetic Disorders. Risks were also calculated for diseases with known non-autosomal recessive aetiology (considered non-consanguinity-related). We estimated adjusted hazard...

  14. Genetic spectrum of autosomal recessive non-syndromic hearing loss in Pakistani families.

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    Sobia Shafique

    Full Text Available The frequency of inherited bilateral autosomal recessive non-syndromic hearing loss (ARNSHL in Pakistan is 1.6/1000 individuals. More than 50% of the families carry mutations in GJB2 while mutations in MYO15A account for about 5% of recessive deafness. In the present study a cohort of 30 ARNSHL families was initially screened for mutations in GJB2 and MYO15A. Homozygosity mapping was performed by employing whole genome single nucleotide polymorphism (SNP genotyping in the families that did not carry mutations in GJB2 or MYO15A. Mutation analysis was performed for the known ARNSHL genes present in the homozygous regions to determine the causative mutations. This allowed the identification of a causative mutation in all the 30 families including 9 novel mutations, which were identified in 9 different families (GJB2 (c.598G>A, p.Gly200Arg; MYO15A (c.9948G>A, p.Gln3316Gln; c.3866+1G>A; c.8767C>T, p.Arg2923* and c.8222T>C, p.Phe2741Ser, TMC1 (c.362+18A>G, BSND (c.97G>C, p.Val33Leu, TMPRSS3 (c.726C>G, p.Cys242Trp and MSRB3 (c.20T>G, p.Leu7Arg. Furthermore, 12 recurrent mutations were detected in 21 other families. The 21 identified mutations included 10 (48% missense changes, 4 (19% nonsense mutations, 3 (14% intronic mutations, 2 (9% splice site mutations and 2 (9% frameshift mutations. GJB2 accounted for 53% of the families, while mutations in MYO15A were the second most frequent (13% cause of ARNSHL in these 30 families. The identification of novel as well as recurrent mutations in the present study increases the spectrum of mutations in known deafness genes which could lead to the identification of novel founder mutations and population specific mutated deafness genes causative of ARNSHL. These results provide detailed genetic information that has potential diagnostic implication in the establishment of cost-efficient allele-specific analysis of frequently occurring variants in combination with other reported mutations in Pakistani populations.

  15. Computational analysis of TRAPPC9: candidate gene for autosomal recessive non-syndromic mental retardation.

    Science.gov (United States)

    Khattak, Naureen Aslam; Mir, Asif

    2014-01-01

    Mental retardation (MR)/ intellectual disability (ID) is a neuro-developmental disorder characterized by a low intellectual quotient (IQ) and deficits in adaptive behavior related to everyday life tasks such as delayed language acquisition, social skills or self-help skills with onset before age 18. To date, a few genes (PRSS12, CRBN, CC2D1A, GRIK2, TUSC3, TRAPPC9, TECR, ST3GAL3, MED23, MAN1B1, NSUN1) for autosomal-recessive forms of non syndromic MR (NS-ARMR) have been identified and established in various families with ID. The recently reported candidate gene TRAPPC9 was selected for computational analysis to explore its potentially important role in pathology as it is the only gene for ID reported in more than five different familial cases worldwide. YASARA (12.4.1) was utilized to generate three dimensional structures of the candidate gene TRAPPC9. Hybrid structure prediction was employed. Crystal Structure of a Conserved Metalloprotein From Bacillus Cereus (3D19-C) was selected as best suitable template using position-specific iteration-BLAST. Template (3D19-C) parameters were based on E-value, Z-score and resolution and quality score of 0.32, -1.152, 2.30°A and 0.684 respectively. Model reliability showed 93.1% residues placed in the most favored region with 96.684 quality factor, and overall 0.20 G-factor (dihedrals 0.06 and covalent 0.39 respectively). Protein-Protein docking analysis demonstrated that TRAPPC9 showed strong interactions of the amino acid residues S(253), S(251), Y(256), G(243), D(131) with R(105), Q(425), W(226), N(255), S(233), its functional partner 1KBKB. Protein-protein interacting residues could facilitate the exploration of structural and functional outcomes of wild type and mutated TRAPCC9 protein. Actively involved residues can be used to elucidate the binding properties of the protein, and to develop drug therapy for NS-ARMR patients.

  16. An Interdisciplinary Approach for Rehabilitating a Patient with Amelogenesis Imperfecta: A Case Report

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    Niloufar Khodaeian

    2012-01-01

    Full Text Available Amelogenesis imperfecta (AI has been defined as a group of hereditary enamel defects. It can be characterized by enamel hypoplasia, hypomaturation, or hypocalcification of the teeth. AI may be associated with some other dental and skeletal developmental defects. Restoration for patients with this condition should be oriented toward the functional and esthetic rehabilitation. This clinical report describes the oral rehabilitation of a young patient diagnosed with the hypoplastic type of AI in posterior teeth and hypomatured type of AI in anterior teeth.

  17. A novel frameshift mutation in KCNQ4 in a family with autosomal recessive non-syndromic hearing loss.

    Science.gov (United States)

    Wasano, Koichiro; Mutai, Hideki; Obuchi, Chie; Masuda, Sawako; Matsunaga, Tatsuo

    2015-08-01

    Mutation of KCNQ4 has been reported to cause autosomal dominant non-syndromic hearing loss (DFNA2A) that usually presents as progressive hearing loss starting from mild to moderate hearing loss during childhood. Here, we identified a novel KCNQ4 mutation, c.1044_1051del8, in a family with autosomal recessive non-syndromic hearing loss. The proband was homozygous for the mutation and was born to consanguineous parents; she showed severe hearing loss that was either congenital or of early childhood onset. The proband had a sister who was heterozygous for the mutation but showed normal hearing. The mutation caused a frameshift that eliminated most of the cytoplasmic C-terminus, including the A-domain, which has an important role for protein tetramerization, and the B-segment, which is a binding site for calmodulin (CaM) that regulates channel function via Ca ions. The fact that the heterozygote had normal hearing indicates that sufficient tetramerization and CaM binding sites were present to preserve a normal phenotype even when only half the proteins contained an A-domain and B-segment. On the other hand, the severe hearing loss in the homozygote suggests that complete loss of the A-domain and B-segment in the protein caused loss of function due to the failure of tetramer formation and CaM binding. This family suggests that some KCNQ4 mutations can cause autosomal recessive hearing loss with more severe phenotype in addition to autosomal dominant hearing loss with milder phenotype. This genotype-phenotype correlation is analogous to that in KCNQ1 which causes autosomal dominant hereditary long QT syndrome 1 with milder phenotype and the autosomal recessive Jervell and Lange-Nielsen syndrome 1 with more severe phenotype due to deletion of the cytoplasmic C-terminus of the potassium channel.

  18. A mutation in the FOXE3 gene causes congenital primary aphakia in an autosomal recessive consanguineous Pakistani family

    DEFF Research Database (Denmark)

    Anjum, Iram; Eiberg, Hans; Baig, Shahid Mahmood;

    2010-01-01

    PURPOSE: Aphakia is the complete absence of any lens in the eye, either due to surgical removal of the lens as a result of a perforating wound or ulcer, or due to a congenital anomaly. The purpose of this study was to elucidate the molecular genetics for a large consanguineous Pakistani family...... with a clear aphakia phenotype. METHODS: The initial homozygosity screening of the family was extended to all the known autosomal recessive cataract loci in order to exclude the possibility of surgical cataract removal leading to aphakia. The screening was performed using polymorphic nucleotide repeat markers...

  19. Arthrogryposis multiplex with deafness, inguinal hernias, and early death: a family report of a probably autosomal recessive trait.

    Science.gov (United States)

    Tiemann, Christian; Bührer, Christoph; Burwinkel, Barbara; Wirtenberger, Michael; Hoehn, Thomas; Hübner, Christoph; van Landeghem, Frank K H; Stoltenburg, Gisela; Obladen, Michael

    2005-08-30

    We report on three male newborn infants of a highly inbred Lebanese family presenting with a characteristic phenotype: arthrogryposis multiplex, deafness, large inguinal hernia, hiccup-like diaphragmatic contractions, and inability to suck, requiring nasogastric gavage feeding. All three boys died from respiratory failure during the first 3 months of life. Intra vitam or post mortem examinations revealed myopathic changes and elevated glycogen content of muscle tissue. This new syndrome is probably transmitted in an autosomal recessive mode, although X-linked inheritance cannot be excluded.

  20. Dentinogenesis imperfecta associated with short stature, hearing loss and mental retardation: a new syndrome with autosomal recessive inheritance?

    Science.gov (United States)

    Cauwels, R G E C; De Coster, P J; Mortier, G R; Marks, L A M; Martens, L C

    2005-08-01

    The follow-up history and oral findings in two brothers from consanguineous parents suggest that the association of dentinogenesis imperfecta (DI), delayed tooth eruption, mild mental retardation, proportionate short stature, sensorineural hearing loss and dysmorphic facies may represent a new syndrome with autosomal recessive inheritance. Histological examination of the dentin matrix of a permanent molar from one of the siblings reveals morphological similarities with defective dentinogenesis as presenting in patients affected with Osteogenesis Imperfecta (OI), a condition caused by deficiency of type I collagen. A number of radiographic and histological characteristics, however, are inconsistent with classical features of DI. These findings suggest that DI may imply greater genetical heterogeneity than currently assumed.

  1. Autosomal recessive MFN2-related Charcot-Marie-Tooth disease with diaphragmatic weakness: Case report and literature review.

    Science.gov (United States)

    Tan, Christopher A; Rabideau, Marina; Blevins, Amy; Westbrook, Marjorie Jody; Ekstein, Tali; Nykamp, Keith; Deucher, Anne; Harper, Amy; Demmer, Laurie

    2016-06-01

    Pathogenic variants in the mitofusin 2 gene (MFN2) are the most common cause of autosomal dominant Charcot-Marie-Tooth (CMT2) disease, which is typically characterized by axonal sensorimotor neuropathy. We report on a 7-month-old white female with hypotonia, motor delay, distal weakness, and motor/sensory axonal neuropathy in which next-generation sequencing analysis identified compound heterozygous pathogenic variants (c.2054_2069_1170del and c.392A>G) in MFN2. A review of the literature reveals that sporadic and familial cases of compound heterozygous or homozygous pathogenic MFN2 variants have been infrequently described, which indicates that MFN2 can also be inherited in a recessive manner. This case highlights several clinical findings not typically associated with MFN2 pathogenic variants, including young age of onset and rapidly progressing diaphragmatic paresis that necessitated tracheostomy and mechanical ventilation, and adds to the growing list of features identified in autosomal recessive MFN2-related CMT2. Our patient with MFN2-related CMT2 expands the clinical and mutational spectrum of individuals with autosomal recessive CMT2 and identifies a new clinical feature that warrants further observation. © 2016 Wiley Periodicals, Inc.

  2. Discriminative Features in Three Autosomal Recessive Cutis Laxa Syndromes: Cutis Laxa IIA, Cutis Laxa IIB, and Geroderma Osteoplastica

    Directory of Open Access Journals (Sweden)

    Ariana Kariminejad

    2017-03-01

    Full Text Available Cutis laxa is a heterogeneous condition characterized by redundant, sagging, inelastic, and wrinkled skin. The inherited forms of this disease are rare and can have autosomal dominant, autosomal recessive, or X-linked inheritance. Three of the autosomal recessive cutis laxa syndromes, namely cutis laxa IIA (ARCL2A, cutis laxa IIB (ARCL2B, and geroderma osteodysplastica (GO, have very similar clinical features, complicating accurate diagnosis. Individuals with these conditions often present with cutis laxa, progeroid features, and hyperextensible joints. These conditions also share additional features, such as short stature, hypotonia, and congenital hip dislocation, but the severity and frequency of these findings are variable in each of these cutis laxa syndromes. The characteristic features for ARCL2A are abnormal isoelectric focusing and facial features, including downslanting palpebral fissures and a long philtrum. Rather, the clinical phenotype of ARCL2B includes severe wrinkling of the dorsum of the hands and feet, wormian bones, athetoid movements, lipodystrophy, cataract and corneal clouding, a thin triangular face, and a pinched nose. Normal cognition and osteopenia leading to pathological fractures, maxillary hypoplasia, and oblique furrowing from the outer canthus to the lateral border of the supraorbital ridge are discriminative features for GO. Here we present 10 Iranian patients who were initially diagnosed clinically using the respective features of each cutis laxa syndrome. Each patient’s clinical diagnosis was then confirmed with molecular investigation of the responsible gene. Review of the clinical features from the cases reported from the literature also supports our conclusions.

  3. Novel MMP20 and KLK4 Mutations in Amelogenesis Imperfecta.

    Science.gov (United States)

    Seymen, F; Park, J-C; Lee, K-E; Lee, H-K; Lee, D-S; Koruyucu, M; Gencay, K; Bayram, M; Tuna, E B; Lee, Z H; Kim, Y-J; Kim, J-W

    2015-08-01

    In order to achieve highly mineralized tooth enamel, enamel proteinases serve the important function of removing the remaining organic matrix in the mineralization and maturation of the enamel matrix. Mutations in the kallikrein 4 (KLK4), enamelysin (MMP20), and WDR72 genes have been identified as causing hypomaturation enamel defects in an autosomal-recessive hereditary pattern. In this report, 2 consanguineous families with a hypomaturation-type enamel defect were recruited, and mutational analysis was performed to determine the molecular genetic etiology of the disease. Whole exome sequencing and autozygosity mapping identified novel homozygous mutations in the KLK4 (c.620_621delCT, p.Ser207Trpfs*38) and MMP20 (c.1054G>A, p.Glu352Lys) genes. Further analysis on the effect of the mutations on the translation, secretion, and function of KLK4 and MMP20 revealed that mutant KLK4 was degraded intracellularly and became inactive while mutant MMP20 was expressed at a normal level but secreted only minimally with proteolytic function.

  4. A novel HSF4 gene mutation (p.R405X causing autosomal recessive congenital cataracts in a large consanguineous family from Pakistan

    Directory of Open Access Journals (Sweden)

    Cheema Abdul

    2008-11-01

    Full Text Available Abstract Background Hereditary cataracts are most frequently inherited as autosomal dominant traits, but can also be inherited in an autosomal recessive or X-linked fashion. To date, 12 loci for autosomal recessive cataracts have been mapped including a locus on chromosome 16q22 containing the disease-causing gene HSF4 (Genbank accession number NM_001040667. Here, we describe a family from Pakistan with the first nonsense mutation in HSF4 thus expanding the mutational spectrum of this heat shock transcription factor gene. Methods A large consanguineous Pakistani family with autosomal recessive cataracts was collected from Quetta. Genetic linkage analysis was performed for the common known autosomal recessive cataracts loci and linkage to a locus containing HSF4 (OMIM 602438 was found. All exons and adjacent splice sites of the heat shock transcription factor 4 gene (HSF4 were sequenced. A mutation-specific restriction enzyme digest (HphI was performed for all family members and unrelated controls. Results The disease phenotype perfectly co-segregated with markers flanking the known cataract gene HSF4, whereas other autosomal recessive loci were excluded. A maximum two-point LOD score with a Zmax = 5.6 at θ = 0 was obtained for D16S421. Direct sequencing of HSF4 revealed the nucleotide exchange c.1213C > T in this family predicting an arginine to stop codon exchange (p.R405X. Conclusion We identified the first nonsense mutation (p.R405X in exon 11 of HSF4 in a large consanguineous Pakistani family with autosomal recessive cataract.

  5. Familial Clustering of Unexplained Transient Respiratory Distress in 12 Newborns from Three Unrelated Families Suggests an Autosomal-Recessive Inheritance

    Directory of Open Access Journals (Sweden)

    Andrea Guala

    2007-01-01

    Full Text Available We report on 12 near-term babies from three families in which an unexplained transient respiratory distress was observed. No known risk factor was present in any family and no sequelae were recorded at follow-up. The most common causes of respiratory distress at birth are Neonatal Respiratory Distress Syndrome (NRD and Transient Tachypnea of the Newborn (TTN, and their cumulative incidence is estimated to be about 2%. Genetic factors have been identified in NRD (surfactant genes or suggested for TTN (genes affecting lung liquid clearance. Survivors from NRD may develop clinically relevant sequelae, while TTN does not cause any problem later in life. Our cases do not immediately fit NRD or TTN, while familial recurrence suggests the existence of a previously unreported subgroup on patients with respiratory distress for which autosomal-recessive inheritance is likely.

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

    DEFF Research Database (Denmark)

    Roos, L; Fang, M; Dali, C;

    2013-01-01

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

  7. A new autosomal recessive syndrome characterized by ocular hypertelorism, distinctive face, mental retardation, brachydactyly, and genital abnormalities.

    Science.gov (United States)

    Spiegel, Ronen; Horovitz, Yoseph; Peters, Hartmut; Erdogan, Fikret; Chervinsky, Ilana; Shalev, Stavit A

    2009-12-01

    We report on three individuals of Muslim Arab origin from a village located in Northern Israel affected by an apparent autosomal recessive syndrome characterized by distinctive facial phenotype of which the most prominent feature is ocular hypertelorism. The other clinical features of the syndrome include variable degree of mental retardation, genital abnormalities dominated by short penis, and skeletal abnormalities including chest deformity (combination of upper pectus carinatum with lower pectus excavatum), and short palms with broad short fingers. Affected individuals displayed distinctive facial features including upslanting palpebral fissures, thick eyebrows, long philtrum, wide mouth with thin upper lip and upturned corners of the mouth, widow's peak, broad nasal bridge, and simple ears with fleshy overfolded helices. This phenotype does not fully meet typical diagnostic features of any known condition.

  8. Familial clustering of unexplained transient respiratory distress in 12 newborns from three unrelated families suggests an autosomal-recessive inheritance.

    Science.gov (United States)

    Guala, Andrea; Carrera, Paola; Pastore, Guido; Somaschini, Marco; Ancora, Gina; Faldella, Giacomo; De Filippi, Paolo; Ferrero, Federica; Guarino, Roberta; Danesino, Cesare

    2007-09-28

    We report on 12 near-term babies from three families in which an unexplained transient respiratory distress was observed. No known risk factor was present in any family and no sequelae were recorded at follow-up. The most common causes of respiratory distress at birth are Neonatal Respiratory Distress Syndrome (NRD) and Transient Tachypnea of the Newborn (TTN), and their cumulative incidence is estimated to be about 2%. Genetic factors have been identified in NRD (surfactant genes) or suggested for TTN (genes affecting lung liquid clearance). Survivors from NRD may develop clinically relevant sequelae, while TTN does not cause any problem later in life. Our cases do not immediately fit NRD or TTN, while familial recurrence suggests the existence of a previously unreported subgroup on patients with respiratory distress for which autosomal-recessive inheritance is likely.

  9. Mutations in C4orf26, encoding a peptide with in vitro hydroxyapatite crystal nucleation and growth activity, cause amelogenesis imperfecta.

    Science.gov (United States)

    Parry, David A; Brookes, Steven J; Logan, Clare V; Poulter, James A; El-Sayed, Walid; Al-Bahlani, Suhaila; Al Harasi, Sharifa; Sayed, Jihad; Raïf, El Mostafa; Shore, Roger C; Dashash, Mayssoon; Barron, Martin; Morgan, Joanne E; Carr, Ian M; Taylor, Graham R; Johnson, Colin A; Aldred, Michael J; Dixon, Michael J; Wright, J Tim; Kirkham, Jennifer; Inglehearn, Chris F; Mighell, Alan J

    2012-09-07

    Autozygosity mapping and clonal sequencing of an Omani family identified mutations in the uncharacterized gene, C4orf26, as a cause of recessive hypomineralized amelogenesis imperfecta (AI), a disease in which the formation of tooth enamel fails. Screening of a panel of 57 autosomal-recessive AI-affected families identified eight further families with loss-of-function mutations in C4orf26. C4orf26 encodes a putative extracellular matrix acidic phosphoprotein expressed in the enamel organ. A mineral nucleation assay showed that the protein's phosphorylated C terminus has the capacity to promote nucleation of hydroxyapatite, suggesting a possible function in enamel mineralization during amelogenesis.

  10. Mitochondrial hsp60 chaperonopathy causes an autosomal-recessive neurodegenerative disorder linked to brain hypomyelination and leukodystrophy.

    Science.gov (United States)

    Magen, Daniella; Georgopoulos, Costa; Bross, Peter; Ang, Debbie; Segev, Yardena; Goldsher, Dorit; Nemirovski, Alexandra; Shahar, Eli; Ravid, Sarit; Luder, Anthony; Heno, Bayan; Gershoni-Baruch, Ruth; Skorecki, Karl; Mandel, Hanna

    2008-07-01

    Hypomyelinating leukodystrophies (HMLs) are disorders involving aberrant myelin formation. The prototype of primary HMLs is the X-linked Pelizaeus-Merzbacher disease (PMD) caused by mutations in PLP1. Recently, homozygous mutations in GJA12 encoding connexin 47 were found in patients with autosomal-recessive Pelizaeus-Merzbacher-like disease (PMLD). However, many patients of both genders with PMLD carry neither PLP1 nor GJA12 mutations. We report a consanguineous Israeli Bedouin kindred with clinical and radiological findings compatible with PMLD, in which linkage to PLP1 and GJA12 was excluded. Using homozygosity mapping and mutation analysis, we have identified a homozygous missense mutation (D29G) not previously described in HSPD1, encoding the mitochondrial heat-shock protein 60 (Hsp60) in all affected individuals. The D29G mutation completely segregates with the disease-associated phenotype. The pathogenic effect of D29G on Hsp60-chaperonin activity was verified by an in vivo E. coli complementation assay, which demonstrated compromised ability of the D29G-Hsp60 mutant protein to support E. coli survival, especially at high temperatures. The disorder, which we have termed MitCHAP-60 disease, can be distinguished from spastic paraplegia 13 (SPG13), another Hsp60-associated autosomal-dominant neurodegenerative disorder, by its autosomal-recessive inheritance pattern, as well as by its early-onset, profound cerebral involvement and lethality. Our findings suggest that Hsp60 defects can cause neurodegenerative pathologies of varying severity, not previously suspected on the basis of the SPG13 phenotype. These findings should help to clarify the important role of Hsp60 in myelinogenesis and neurodegeneration.

  11. Mutations in C8orf37, encoding a ciliary protein, are associated with autosomal-recessive retinal dystrophies with early macular involvement.

    NARCIS (Netherlands)

    Estrada-Cuzcano, A.; Neveling, K.; Kohl, S.; Banin, E.; Rotenstreich, Y.; Sharon, D.; Falik-Zaccai, T.C.; Hipp, S.; Roepman, R.; Wissinger, B.; Letteboer, S.J.F.; Mans, D.A.; Blokland, E.A.W.; Kwint, M.P.; Gijsen, S.J.; Huet, R.A.C. van; Collin, R.W.J.; Scheffer, H.; Veltman, J.A.; Zrenner, E.; Hollander, A.I. den; Klevering, B.J.; Cremers, F.P.M.

    2012-01-01

    Cone-rod dystrophy (CRD) and retinitis pigmentosa (RP) are clinically and genetically overlapping heterogeneous retinal dystrophies. By using homozygosity mapping in an individual with autosomal-recessive (ar) RP from a consanguineous family, we identified three sizeable homozygous regions, together

  12. A novel locus for autosomal recessive nonsyndromic hearing impairment, DFNB63, maps to chromosome 11q13.2-q13.4.

    NARCIS (Netherlands)

    Kalay, E.; Caylan, R.; Kiroglu, A.F.; Yasar, T.; Collin, R.W.J.; Heister, J.G.A.M.; Oostrik, J.; Cremers, C.W.R.J.; Brunner, H.G.; Karaguzel, A.; Kremer, H.

    2007-01-01

    Hereditary hearing impairment is a genetically heterogeneous disorder. To date, 49 autosomal recessive nonsyndromic hearing impairment (ARNSHI) loci have been described, and there are more than 16 additional loci announced. In 25 of the known loci, causative genes have been identified. A genome scan

  13. Autosomal-recessive posterior microphthalmos is caused by mutations in PRSS56, a gene encoding a trypsin-like serine protease

    DEFF Research Database (Denmark)

    Gal, Andreas; Rau, Isabella; El Matri, Leila

    2011-01-01

    Posterior microphthalmos (MCOP) is a rare isolated developmental anomaly of the eye characterized by extreme hyperopia due to short axial length. The population of the Faroe Islands shows a high prevalence of an autosomal-recessive form (arMCOP) of the disease. Based on published linkage data, we...

  14. Amelogenesis imperfecta: Report of a case and review of literature

    Directory of Open Access Journals (Sweden)

    Chaudhary Mayur

    2009-01-01

    Full Text Available Amelogenesis imperfecta (AI is a diverse collection of inherited diseases that exhibit quantitative or qualitative tooth enamel defects in the absence of systemic manifestations. Also known by varied names such as Hereditary enamel dysplasia, Hereditary brown enamel, Hereditary brown opalescent teeth, this defect is entirely ectodermal, since mesodermal components of the teeth are basically normal. The AI trait can be transmitted by either autosomal dominant, autosomal recessive, or X-linked modes of inheritance. Genes implicated in autosomal forms are genes encoding enamel matrix proteins, namely: enamelin and ameloblastin, tuftelin, MMP-20 and kallikrein - 4. This article presents a case reported to Dr. D. Y. Patil, Dental College and Hospital, Pune, India, along with a review of this often seen clinical entity.

  15. Novel Mutations and Mutation Combinations of TMPRSS3 Cause Various Phenotypes in One Chinese Family with Autosomal Recessive Hearing Impairment

    Science.gov (United States)

    Wang, Guo-Jian; Xu, Jin-Cao; Su, Yu

    2017-01-01

    Autosomal recessive hearing impairment with postlingual onset is rare. Exceptions are caused by mutations in the TMPRSS3 gene, which can lead to prelingual (DFNB10) as well as postlingual deafness (DFNB8). TMPRSS3 mutations can be classified as mild or severe, and the phenotype is dependent on the combination of TMPRSS3 mutations. The combination of two severe mutations leads to profound hearing impairment with a prelingual onset, whereas severe mutations in combination with milder TMPRSS3 mutations lead to a milder phenotype with postlingual onset. We characterized a Chinese family (number FH1523) with not only prelingual but also postlingual hearing impairment. Three mutations in TMPRSS3, one novel mutation c.36delC [p.(Phe13Serfs⁎12)], and two previously reported pathogenic mutations, c.916G>A (p.Ala306Thr) and c.316C>T (p.Arg106Cys), were identified. Compound heterozygous mutations of p.(Phe13Serfs⁎12) and p.Ala306Thr manifest as prelingual, profound hearing impairment in the patient (IV: 1), whereas the combination of p.Arg106Cys and p.Ala306Thr manifests as postlingual, milder hearing impairment in the patient (II: 2, II: 3, II: 5), suggesting that p.Arg106Cys mutation has a milder effect than p.(Phe13Serfs⁎12). We concluded that different combinations of TMPRSS3 mutations led to different hearing impairment phenotypes (DFNB8/DFNB10) in this family. PMID:28246597

  16. Autosomal recessive spastic paraplegia (SPG45) with mental retardation maps to 10q24.3-q25.1.

    Science.gov (United States)

    Dursun, Umut; Koroglu, Cigdem; Kocasoy Orhan, Elif; Ugur, Sibel Aylin; Tolun, Aslihan

    2009-10-01

    Hereditary spastic paraplegias (HSPs) are characterized by progressive spasticity in the lower limbs. They are clinically heterogeneous, and pure forms as well as complicated forms with other accompanying clinical findings are known. HSPs are also genetically heterogeneous. We performed clinical and genetic studies in a consanguineous family with five affected members. A genome scan using 405 microsatellite markers for eight members of the family identified candidate gene loci, and subsequent fine mapping in 16 members identified the gene locus responsible for the HSP. The clinical manifestations were very early onset spastic paraplegia (SPG) accompanied by mental retardation and ocular signs. The gene locus was identified as the interval 102.05-106.64 Mbp on chromosome 10. Gene MRPL43 was analyzed in the patients. No mutation but high levels of mRNA were detected. We have mapped a novel autosomal recessive complicated form of HSP (SPG45) to a 4.6-Mbp region at 10q24.3-q25.1 with multipoint logarithm of odds scores >4.5.

  17. Autosomal recessive posterior column ataxia with retinitis pigmentosa caused by novel mutations in the FLVCR1 gene.

    Science.gov (United States)

    Shaibani, Aziz; Wong, Lee-Jun; Wei Zhang, Victor; Lewis, Richard Alan; Shinawi, Marwan

    2015-01-01

    Posterior column ataxia with retinitis pigmentosa (PCARP) is an autosomal recessive disorder characterized by severe sensory ataxia, muscle weakness and atrophy, and progressive pigmentary retinopathy. Recently, mutations in the FLVCR1 gene were described in four families with this condition. We investigated the molecular basis and studied the phenotype of PCARP in a new family. The proband is a 33-year-old woman presented with sensory polyneuropathy and retinitis pigmentosa (RP). The constellation of clinical findings with normal metabolic and genetic evaluation, including mitochondrial DNA (mtDNA) analysis and normal levels of phytanic acid and vitamin E, prompted us to seek other causes of our patient's condition. Sequencing of FLVCR1 in the proband and targeted mutation testing in her two affected siblings revealed two novel variants, c.1547G > A (p.R516Q) and c.1593+5_+8delGTAA predicted, respectively, to be highly conserved throughout evolution and affecting the normal splicing, therefore, deleterious. This study supports the pathogenic role of FLVCR1 in PCARP and expands the molecular and clinical spectra of PCARP. We show for the first time that nontransmembrane domain (TMD) mutations in the FLVCR1 can cause PCARP, suggesting different mechanisms for pathogenicity. Our clinical data reveal that impaired sensation can be part of the phenotypic spectrum of PCARP. This study along with previously reported cases suggests that targeted sequencing of the FLVCR1 gene should be considered in patients with severe sensory ataxia, RP, and peripheral sensory neuropathy.

  18. A novel deletion partly removing the AVP gene causes autosomal recessive inheritance of early-onset neurohypophyseal diabetes insipidus.

    Science.gov (United States)

    Christensen, J H; Kvistgaard, H; Knudsen, J; Shaikh, G; Tolmie, J; Cooke, S; Pedersen, S; Corydon, T J; Gregersen, N; Rittig, S

    2013-01-01

    Familial neurohypophyseal diabetes insipidus (FNDI) typically presents with age-dependent penetrance and autosomal dominant inheritance caused by missense variations in one allele of the AVP gene encoding the arginine vasopressin (AVP) prohormone. We present the molecular genetic characteristics underlying an unusual form of FNDI occurring with very early onset and seemingly autosomal recessive inheritance. By DNA amplification and sequencing, we identified a novel variant allele of the AVP gene carrying a 10,396 base pair deletion involving the majority of the AVP gene as well as its regulatory sequences in the intergenic region between the AVP and the OXT gene, encoding the oxytocin prohormone. We found two chromosomes carrying the deletion in affected family members and one in unaffected family members suspected to transmit the deleted allele. Whole-genome array analysis confirmed the results and excluded the presence of any additional major pathogenic abnormalities. The deletion is predicted to abolish the transcription of the AVP gene, thus the fact that family members heterozygous for the deletion remain healthy argues, in general, against haploinsufficiency as the pathogenic mechanism FNDI. Accordingly, our data is strong support to the prevailing idea that dominant inheritance of FNDI is due to a dominant-negative effect exerted by variant AVP prohormone.

  19. Genetic forms of nephrogenic diabetes insipidus (NDI): Vasopressin receptor defect (X-linked) and aquaporin defect (autosomal recessive and dominant).

    Science.gov (United States)

    Bichet, Daniel G; Bockenhauer, Detlef

    2016-03-01

    Nephrogenic diabetes insipidus (NDI), which can be inherited or acquired, is characterized by an inability to concentrate urine despite normal or elevated plasma concentrations of the antidiuretic hormone, arginine vasopressin (AVP). Polyuria with hyposthenuria and polydipsia are the cardinal clinical manifestations of the disease. About 90% of patients with congenital NDI are males with X-linked NDI who have mutations in the vasopressin V2 receptor (AVPR2) gene encoding the vasopressin V2 receptor. In less than 10% of the families studied, congenital NDI has an autosomal recessive or autosomal dominant mode of inheritance with mutations in the aquaporin-2 (AQP2) gene. When studied in vitro, most AVPR2 and AQP2 mutations lead to proteins trapped in the endoplasmic reticulum and are unable to reach the plasma membrane. Prior knowledge of AVPR2 or AQP2 mutations in NDI families and perinatal mutation testing is of direct clinical value and can avert the physical and mental retardation associated with repeated episodes of dehydration.

  20. Linkage of autosomal recessive primary congenital glaucoma to the GLC3A locus in Roms (Gypsies) from Slovakia.

    Science.gov (United States)

    Plásilová, M; Feráková, E; Kádasi, L; Poláková, H; Gerinec, A; Ott, J; Ferák, V

    1998-01-01

    The autosomal recessive form of primary congenital glaucoma (gene symbol GLC3) has been recently mapped to two different loci, GLC3A (at 2p21), and GLC3B (at 1p36), respectively, on families of Turkish and Saudi Arabian provenance. This disorder is known to occur with an extremely high incidence in Roms (Gypsies) in Slovakia. We performed a standard linkage analysis on a sample of 7 Slovak Gypsy families comprising 18 affected members, and found significant linkage with four STR markers from the chromosomal region of 2p21 (D2S1788, D2S1346, D2S2328, and D2S1356), without heterogeneity. This finding demonstrates that in the Rom population of Slovakia, primary congenital glaucoma is due to the locus GLC3A, and consequently, to the mutation(s) in the cytochrome P4501B1 gene, which has been recently identified as the principal cause of the disease. Roms represent the third population, in which the disorder has been mapped to GLC3A.

  1. Preimplantation genetic diagnosis for a Chinese family with autosomal recessive Meckel-Gruber syndrome type 3 (MKS3.

    Directory of Open Access Journals (Sweden)

    Yanping Lu

    Full Text Available Meckel-Gruber syndrome type 3 is an autosomal recessive genetic defect caused by mutations in TMEM67 gene. In our previous study, we have identified a homozygous TMEM67 mutation in a Chinese family exhibiting clinical characteristics of MKS3, which provided a ground for further PGD procedure. Here we report the development and the first clinical application of the PGD for this MKS3 family. Molecular analysis protocol for clinical PGD procedure was established using 50 single cells in pre-clinical set-up. After whole genomic amplification by multiple displacement amplification with the DNA from single cells, three techniques were applied simultaneously to increase the accuracy and reliability of genetic diagnosis in single blastomere, including real-time PCR with Taq Man-MGB probe, haplotype analysis with polymorphic STR markers and Sanger sequencing. In the clinical PGD cycle, nine embryos at cleavage-stage were biopsied and subjected to genetic diagnosis. Two embryos diagnosed as free of TMEM67 mutation were transferred and one achieving normal pregnancy. Non-invasive prenatal assessment of trisomy 13, 18 and 21 by multiplex DNA sequencing at 18 weeks' gestation excluded the aneuploidy of the analyzed chromosomes. A healthy boy was delivered by cesarean section at 39 weeks' gestation. DNA sequencing from his cord blood confirmed the result of genetic analysis in the PGD cycle. The protocol developed in this study was proved to be rapid and safe for the detection of monogenic mutations in clinical PGD cycle.

  2. Localization of a gene for an autosomal recessive form of juvenile Parkinsonism to chromosome 6q25.2-27

    Energy Technology Data Exchange (ETDEWEB)

    Matsumine, Hiroto; Shimoda-Matsubayashi, Satoe; Nakagawa-Hattori, Yuko [Tokyo Metropolitan Ebara Hospital (Japan)] [and others

    1997-03-01

    An autosomal recessive form of juvenile Parkinsonism (AR-JP) (MIM 600116) is a levodopa-responsive Parkinsonism whose pathological finding is a highly selective degeneration of dopaminergic neurons in the zona compacta of the substantia nigra. By linkage analysis of diallelic polymorphism of the Mn-superoxide dismutase gene (SOD2), we found a family with AR-JP showing perfect segregation of the disease with the SOD2 locus. By extending the linkage analysis to 13 families with AR-JP, we discovered strong evidence for the localization of the AR-JP gene at chromosome 6q25.2-27, including the SOD2 locus, with the maximal cumulative pairwise LOD scores of 7.26 and 7.71 at D6S305 ({theta} = .03) and D6S253 ({theta} = .02), respectively. Observation of obligate recombination events, as well as multipoint linkage analysis, placed the AR-JP gene in a 17-cM interval between D6S437 and D6S264. Delineation of the AR-JP gene will be an important step toward our understanding of the molecular mechanism underlying selective degeneration of the nigral neurons. 38 refs., 4 figs., 1 tab.

  3. Mutations in the histamine N-methyltransferase gene, HNMT, are associated with nonsyndromic autosomal recessive intellectual disability

    Science.gov (United States)

    Heidari, Abolfazl; Tongsook, Chanakan; Najafipour, Reza; Musante, Luciana; Vasli, Nasim; Garshasbi, Masoud; Hu, Hao; Mittal, Kirti; McNaughton, Amy J. M.; Sritharan, Kumudesh; Hudson, Melissa; Stehr, Henning; Talebi, Saeid; Moradi, Mohammad; Darvish, Hossein; Arshad Rafiq, Muhammad; Mozhdehipanah, Hossein; Rashidinejad, Ali; Samiei, Shahram; Ghadami, Mohsen; Windpassinger, Christian; Gillessen-Kaesbach, Gabriele; Tzschach, Andreas; Ahmed, Iltaf; Mikhailov, Anna; Stavropoulos, D. James; Carter, Melissa T.; Keshavarz, Soraya; Ayub, Muhammad; Najmabadi, Hossein; Liu, Xudong; Ropers, Hans Hilger; Macheroux, Peter; Vincent, John B.

    2015-01-01

    Histamine (HA) acts as a neurotransmitter in the brain, which participates in the regulation of many biological processes including inflammation, gastric acid secretion and neuromodulation. The enzyme histamine N-methyltransferase (HNMT) inactivates HA by transferring a methyl group from S-adenosyl-l-methionine to HA, and is the only well-known pathway for termination of neurotransmission actions of HA in mammalian central nervous system. We performed autozygosity mapping followed by targeted exome sequencing and identified two homozygous HNMT alterations, p.Gly60Asp and p.Leu208Pro, in patients affected with nonsyndromic autosomal recessive intellectual disability from two unrelated consanguineous families of Turkish and Kurdish ancestry, respectively. We verified the complete absence of a functional HNMT in patients using in vitro toxicology assay. Using mutant and wild-type DNA constructs as well as in silico protein modeling, we confirmed that p.Gly60Asp disrupts the enzymatic activity of the protein, and that p.Leu208Pro results in reduced protein stability, resulting in decreased HA inactivation. Our results highlight the importance of inclusion of HNMT for genetic testing of individuals presenting with intellectual disability. PMID:26206890

  4. Modeling autosomal recessive cutis laxa type 1C in mice reveals distinct functions for Ltbp-4 isoforms

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    Insa Bultmann-Mellin

    2015-04-01

    Full Text Available Recent studies have revealed an important role for LTBP-4 in elastogenesis. Its mutational inactivation in humans causes autosomal recessive cutis laxa type 1C (ARCL1C, which is a severe disorder caused by defects of the elastic fiber network. Although the human gene involved in ARCL1C has been discovered based on similar elastic fiber abnormalities exhibited by mice lacking the short Ltbp-4 isoform (Ltbp4S−/−, the murine phenotype does not replicate ARCL1C. We therefore inactivated both Ltbp-4 isoforms in the mouse germline to model ARCL1C. Comparative analysis of Ltbp4S−/− and Ltbp4-null (Ltbp4−/− mice identified Ltbp-4L as an important factor for elastogenesis and postnatal survival, and showed that it has distinct tissue expression patterns and specific molecular functions. We identified fibulin-4 as a previously unknown interaction partner of both Ltbp-4 isoforms and demonstrated that at least Ltbp-4L expression is essential for incorporation of fibulin-4 into the extracellular matrix (ECM. Overall, our results contribute to the current understanding of elastogenesis and provide an animal model of ARCL1C.

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

    Science.gov (United States)

    Roos, L; Fang, M; Dali, C; Jensen, H; Christoffersen, N; Wu, B; Zhang, J; Xu, R; Harris, P; Xu, X; Grønskov, K; Tümer, Z

    2014-09-01

    Anomalies of eye development can lead to the rare eye malformations microphthalmia and anophthalmia (small or absent ocular globes), which are genetically very heterogeneous. Several genes have been associated with microphthalmia and anophthalmia, and exome sequencing has contributed to the identification of new genes. Very recently, homozygous variations within ALDH1A3 have been associated with autosomal recessive microphthalmia with or without cysts or coloboma, and with variable subphenotypes of developmental delay/autism spectrum disorder in eight families. In a consanguineous family where three of the five siblings were affected with microphthalmia/coloboma, we identified a novel homozygous missense mutation in ALDH1A3 using exome sequencing. Of the three affected siblings, one had intellectual disability and one had intellectual disability and autism, while the last one presented with normal development. This study contributes further to the description of the clinical spectrum associated with ALDH1A3 mutations, and illustrates the interfamilial clinical variation observed in individuals with ALDH1A3 mutations.

  6. Novel genetic linkage of rat Sp6 mutation to Amelogenesis imperfecta

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    Muto Taro

    2012-06-01

    Full Text Available Abstract Background Amelogenesis imperfecta (AI is an inherited disorder characterized by abnormal formation of tooth enamel. Although several genes responsible for AI have been reported, not all causative genes for human AI have been identified to date. AMI rat has been reported as an autosomal recessive mutant with hypoplastic AI isolated from a colony of stroke-prone spontaneously hypertensive rat strain, but the causative gene has not yet been clarified. Through a genetic screen, we identified the causative gene of autosomal recessive AI in AMI and analyzed its role in amelogenesis. Methods cDNA sequencing of possible AI-candidate genes so far identified using total RNA of day 6 AMI rat molars identified a novel responsible mutation in specificity protein 6 (Sp6. Genetic linkage analysis was performed between Sp6 and AI phenotype in AMI. To understand a role of SP6 in AI, we generated the transgenic rats harboring Sp6 transgene in AMI (Ami/Ami + Tg. Histological analyses were performed using the thin sections of control rats, AMI, and Ami/Ami + Tg incisors in maxillae, respectively. Results We found the novel genetic linkage between a 2-bp insertional mutation of Sp6 gene and the AI phenotype in AMI rats. The position of mutation was located in the coding region of Sp6, which caused frameshift mutation and disruption of the third zinc finger domain of SP6 with 11 cryptic amino acid residues and a stop codon. Transfection studies showed that the mutant protein can be translated and localized in the nucleus in the same manner as the wild-type SP6 protein. When we introduced the CMV promoter-driven wild-type Sp6 transgene into AMI rats, the SP6 protein was ectopically expressed in the maturation stage of ameloblasts associated with the extended maturation stage and the shortened reduced stage without any other phenotypical changes. Conclusion We propose the addition of Sp6 mutation as a new molecular diagnostic criterion for the

  7. Amelogenesis imperfecta

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    K P Mahesh

    2012-01-01

    Full Text Available Amelogenesis imperfecta (AI represents a group of developmental disorder of teeth structure, genomic in origin, which affects the structure and clinical appearance of enamel of all or nearly all the teeth, and which may be associated with morphologic or biochemical changes elsewhere in the body. It can be hypoplastic, hypomineralized, or both. Teeth affected may be discoloured, sensitive, or prone to disintegration. A case of yellow brown discoloration in a hindu female aged 26, reported with same chief complaint. On examination of the patient, generalized yellowish brown discoloration of the teeth was seen. Radiographic and histopathologic examination confirms the diagnosis of AI.

  8. Loss of VPS13C Function in Autosomal-Recessive Parkinsonism Causes Mitochondrial Dysfunction and Increases PINK1/Parkin-Dependent Mitophagy

    Science.gov (United States)

    Lesage, Suzanne; Drouet, Valérie; Majounie, Elisa; Deramecourt, Vincent; Jacoupy, Maxime; Nicolas, Aude; Cormier-Dequaire, Florence; Hassoun, Sidi Mohamed; Pujol, Claire; Ciura, Sorana; Erpapazoglou, Zoi; Usenko, Tatiana; Maurage, Claude-Alain; Sahbatou, Mourad; Liebau, Stefan; Ding, Jinhui; Bilgic, Basar; Emre, Murat; Erginel-Unaltuna, Nihan; Guven, Gamze; Tison, François; Tranchant, Christine; Vidailhet, Marie; Corvol, Jean-Christophe; Krack, Paul; Leutenegger, Anne-Louise; Nalls, Michael A.; Hernandez, Dena G.; Heutink, Peter; Gibbs, J. Raphael; Hardy, John; Wood, Nicholas W.; Gasser, Thomas; Durr, Alexandra; Deleuze, Jean-François; Tazir, Meriem; Destée, Alain; Lohmann, Ebba; Kabashi, Edor; Singleton, Andrew; Corti, Olga; Brice, Alexis; Lesage, Suzanne; Tison, François; Vidailhet, Marie; Corvol, Jean-Christophe; Agid, Yves; Anheim, Mathieu; Bonnet, Anne-Marie; Borg, Michel; Broussolle, Emmanuel; Damier, Philippe; Destée, Alain; Dürr, Alexandra; Durif, Franck; Krack, Paul; Klebe, Stephan; Lohmann, Ebba; Martinez, Maria; Pollak, Pierre; Rascol, Olivier; Tranchant, Christine; Vérin, Marc; Viallet, François; Brice, Alexis; Lesage, Suzanne; Majounie, Elisa; Tison, François; Vidailhet, Marie; Corvol, Jean Christophe; Nalls, Michael A.; Hernandez, Dena G.; Gibbs, J. Raphael; Dürr, Alexandra; Arepalli, Sampath; Barker, Roger A.; Ben-Shlomo, Yoav; Berg, Daniela; Bettella, Francesco; Bhatia, Kailash; de Bie, Rob M.A.; Biffi, Alessandro; Bloem, Bastiaan R.; Bochdanovits, Zoltan; Bonin, Michael; Lesage, Suzanne; Tison, François; Vidailhet, Marie; Corvol, Jean-Christophe; Agid, Yves; Anheim, Mathieu; Bonnet, Anne-Marie; Borg, Michel; Broussolle, Emmanuel; Damier, Philippe; Destée, Alain; Dürr, Alexandra; Durif, Franck; Krack, Paul; Klebe, Stephan; Lohmann, Ebba; Martinez, Maria; Pollak, Pierre; Rascol, Olivier; Tranchant, Christine; Vérin, Marc; Bras, Jose M.; Brockmann, Kathrin; Brooks, Janet; Burn, David J.; Charlesworth, Gavin; Chen, Honglei; Chinnery, Patrick F.; Chong, Sean; Clarke, Carl E.; Cookson, Mark R.; Counsell, Carl; Damier, Philippe; Dartigues, Jean-François; Deloukas, Panos; Deuschl, Günther; Dexter, David T.; van Dijk, Karin D.; Dillman, Allissa; Dong, Jing; Durif, Frank; Edkins, Sarah; Escott-Price, Valentina; Evans, Jonathan R.; Foltynie, Thomas; Gao, Jianjun; Gardner, Michelle; Goate, Alison; Gray, Emma; Guerreiro, Rita; Harris, Clare; van Hilten, Jacobus J.; Hofman, Albert; Hollenbeck, Albert; Holmans, Peter; Holton, Janice; Hu, Michèle; Huang, Xuemei; Huber, Heiko; Hudson, Gavin; Hunt, Sarah E.; Huttenlocher, Johanna; Illig, Thomas; Jónsson, Pálmi V.; Kilarski, Laura L.; Jansen, Iris E.; Lambert, Jean-Charles; Langford, Cordelia; Lees, Andrew; Lichtner, Peter; Limousin, Patricia; Lopez, Grisel; Lorenz, Delia; Lubbe, Steven; Lungu, Codrin; Martinez, María; Mätzler, Walter; McNeill, Alisdair; Moorby, Catriona; Moore, Matthew; Morrison, Karen E.; Mudanohwo, Ese; O’Sullivan, Sean S.; Owen, Michael J.; Pearson, Justin; Perlmutter, Joel S.; Pétursson, Hjörvar; Plagnol, Vincent; Pollak, Pierre; Post, Bart; Potter, Simon; Ravina, Bernard; Revesz, Tamas; Riess, Olaf; Rivadeneira, Fernando; Rizzu, Patrizia; Ryten, Mina; Saad, Mohamad; Simón-Sánchez, Javier; Sawcer, Stephen; Schapira, Anthony; Scheffer, Hans; Schulte, Claudia; Sharma, Manu; Shaw, Karen; Sheerin, Una-Marie; Shoulson, Ira; Shulman, Joshua; Sidransky, Ellen; Spencer, Chris C.A.; Stefánsson, Hreinn; Stefánsson, Kári; Stockton, Joanna D.; Strange, Amy; Talbot, Kevin; Tanner, Carlie M.; Tashakkori-Ghanbaria, Avazeh; Trabzuni, Daniah; Traynor, Bryan J.; Uitterlinden, André G.; Velseboer, Daan; Walker, Robert; van de Warrenburg, Bart; Wickremaratchi, Mirdhu; Williams-Gray, Caroline H.; Winder-Rhodes, Sophie; Wurster, Isabel; Williams, Nigel; Morris, Huw R.; Heutink, Peter; Hardy, John; Wood, Nicholas W.; Gasser, Thomas; Singleton, Andrew B.; Brice, Alexis

    2016-01-01

    Autosomal-recessive early-onset parkinsonism is clinically and genetically heterogeneous. The genetic causes of approximately 50% of autosomal-recessive early-onset forms of Parkinson disease (PD) remain to be elucidated. Homozygozity mapping and exome sequencing in 62 isolated individuals with early-onset parkinsonism and confirmed consanguinity followed by data mining in the exomes of 1,348 PD-affected individuals identified, in three isolated subjects, homozygous or compound heterozygous truncating mutations in vacuolar protein sorting 13C (VPS13C). VPS13C mutations are associated with a distinct form of early-onset parkinsonism characterized by rapid and severe disease progression and early cognitive decline; the pathological features were striking and reminiscent of diffuse Lewy body disease. In cell models, VPS13C partly localized to the outer membrane of mitochondria. Silencing of VPS13C was associated with lower mitochondrial membrane potential, mitochondrial fragmentation, increased respiration rates, exacerbated PINK1/Parkin-dependent mitophagy, and transcriptional upregulation of PARK2 in response to mitochondrial damage. This work suggests that loss of function of VPS13C is a cause of autosomal-recessive early-onset parkinsonism with a distinctive phenotype of rapid and severe progression. PMID:26942284

  9. Possible influences on the expression of X chromosome-linked dystrophin abnormalities by heterozygosity for autosomal recessive Fukuyama congenital muscular dystrophy

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    Beggs, A.H.; Neumann, P.E.; Anderson, M.S.; Kunkel, L.M. (Harvard Medical School, Boston, MA (United States)); Arahata, Kiichi; Arikawa, Eri; Nonaka, Ikuya (National Inst. of Neuroscience, Tokyo (Japan))

    1992-01-15

    Abnormalities of dystrophin, a cytoskeletal protein of muscle and nerve, are generally considered specific for Duchenne and Becker muscular dystrophy. However, several patients have recently been identified with dystrophin deficiency who, before dystrophin testing, were considered to have Fukuyama congenital muscular dystrophy (FCMD) on the basis of clinical findings. Epidemiologic data suggest that only 1/3,500 males with autosomal recessive FCMD should have abnormal dystrophin. To explain the observation of 3/23 FCMD males with abnormal dystrophin, the authors propose that dystrophin and the FCMD gene product interact and that the earlier onset and greater severity of these patients' phenotype (relative to Duchenne muscular dystrophy) are due to their being heterozygous for the FCMD mutation in addition to being hemizygous for Duchenne muscular dystrophy, a genotype that is predicted to occur in 1/175,000 Japanese males. This model may help explain the genetic basis for some of the clinical and pathological variability seen among patients with FCMD, and it has potential implications for understanding the inheritance of other autosomal recessive disorders in general. For example, sex ratios for rare autosomal recessive disorders caused by mutations in proteins that interact with X chromosome-linked gene products may display predictable deviation from 1:1.

  10. Loss of ZMPSTE24 (FACE-1) causes autosomal recessive restrictive dermopathy and accumulation of Lamin A precursors.

    Science.gov (United States)

    Navarro, Claire L; Cadiñanos, Juan; De Sandre-Giovannoli, Annachiara; Bernard, Rafaëlle; Courrier, Sébastien; Boccaccio, Irène; Boyer, Amandine; Kleijer, Wim J; Wagner, Anja; Giuliano, Fabienne; Beemer, Frits A; Freije, Jose M; Cau, Pierre; Hennekam, Raoul C M; López-Otín, Carlos; Badens, Catherine; Lévy, Nicolas

    2005-06-01

    Restrictive dermopathy (RD) is characterized by intrauterine growth retardation, tight and rigid skin with prominent superficial vessels, bone mineralization defects, dysplastic clavicles, arthrogryposis and early neonatal death. In two patients affected with RD, we recently reported two different heterozygous splicing mutations in the LMNA gene, leading to the production and accumulation of truncated Prelamin A. In other patients, a single nucleotide insertion was identified in ZMPSTE24. This variation is located in a homopolymeric repeat of thymines and introduces a premature termination codon. ZMPSTE24 encodes an endoprotease essential for the post-translational cleavage of the Lamin A precursor and the production of mature Lamin A. However, the autosomal recessive inheritance of RD suggested that a further molecular defect was present either in the second ZMPSTE24 allele or in another gene involved in Lamin A processing. Here, we report new findings in RD linked to ZMPSTE24 mutations. Ten RD patients were analyzed including seven from a previous series and three novel patients. All were found to be either homozygous or compound heterozygous for ZMPSTE24 mutations. We report three novel 'null' mutations as well as the recurrent thymine insertion. In all cases, we find a complete absence of both ZMPSTE24 and mature Lamin A associated with Prelamin A accumulation. Thus, RD is either a primary or a secondary laminopathy, caused by dominant de novo LMNA mutations or, more frequently, recessive null ZMPSTE24 mutations, most of which lie in a mutation hotspot within exon 9. The accumulation of truncated or normal length Prelamin A is, therefore, a shared pathophysiological feature in recessive and dominant RD. These findings have an important impact on our knowledge of the pathophysiology in Progeria and related disorders and will help direct the development of therapeutic approaches.

  11. Canine disorder mirrors human disease: exonic deletion in HES7 causes autosomal recessive spondylocostal dysostosis in miniature Schnauzer dogs.

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    Cali E Willet

    Full Text Available Spondylocostal dysostosis is a congenital disorder of the axial skeleton documented in human families from diverse racial backgrounds. The condition is characterised by truncal shortening, extensive hemivertebrae and rib anomalies including malalignment, fusion and reduction in number. Mutations in the Notch signalling pathway genes DLL3, MESP2, LFNG, HES7 and TBX6 have been associated with this defect. In this study, spondylocostal dysostosis in an outbred family of miniature schnauzer dogs is described. Computed tomography demonstrated that the condition mirrors the skeletal defects observed in human cases, but unlike most human cases, the affected dogs were stillborn or died shortly after birth. Through gene mapping and whole genome sequencing, we identified a single-base deletion in the coding region of HES7. The frameshift mutation causes loss of functional domains essential for the oscillatory transcriptional autorepression of HES7 during somitogenesis. A restriction fragment length polymorphism test was applied within the immediate family and supported a highly penetrant autosomal recessive mode of inheritance. The mutation was not observed in wider testing of 117 randomly sampled adult miniature schnauzer and six adult standard schnauzer dogs; providing a significance of association of Praw = 4.759e-36 (genome-wide significant. Despite this apparently low frequency in the Australian population, the allele may be globally distributed based on its presence in two unrelated sires from geographically distant locations. While isolated hemivertebrae have been observed in a small number of other dog breeds, this is the first clinical and genetic diagnosis of spontaneously occurring spondylocostal dysostosis in a non-human mammal and offers an excellent model in which to study this devastating human disorder. The genetic test can be utilized by dog breeders to select away from the disease and avoid unnecessary neonatal losses.

  12. Analysis of missense variants in the PKHD1-gene in patients with autosomal recessive polycystic kidney disease (ARPKD).

    Science.gov (United States)

    Losekoot, Monique; Haarloo, Cathleen; Ruivenkamp, Claudia; White, Stefan J; Breuning, Martijn H; Peters, Dorien J M

    2005-11-01

    Autosomal recessive polycystic kidney disease (ARPKD) is a severe form of polycystic kidney disease characterized by enlarged kidneys and congenital hepatic fibrosis. Given the poor prognosis for the majority of children with the severe perinatal ARPKD phenotype, there is a regular request for prenatal testing. ARPKD is caused by mutations in the polycystic kidney and hepatic disease 1 (PKHD1) gene, which consists of 86 exons that are variably assembled into a number of alternatively spliced transcripts. The longest transcript, comprising 67 exons, encodes the protein fibrocystin/polyductin. We have set up mutation analysis by direct sequencing of these 67 exons. In 39 mainly Dutch families we identified: 11 nonsense mutations, 15 deletions/insertions, 5 splice site mutations, and 39 missense mutations. To classify missense variants we combined evolutionary conservation, using the human, chimpanzee, dog, mouse, chicken and frog Pkhd1 sequences, with the Grantham score for chemical differences. Thirty-three missense mutations were considered pathogenic and seven were classified as rare, probably pathogenic variants. In addition to sequence analysis, multiplex ligation-dependent probe amplification (MLPA) was used to identify multiple exon deletions. However, no large deletions in the PKHD1 gene were identified. In 31 index patients two mutations were found, in 6 patients one mutation was found, leading to a mutation detection rate of 87%. The analysis of amino acid conservation as well as applying the Grantham score for chemical differences allowed us to determine the pathogeneity for nearly all new missense mutations and thus proved to be useful tools to classify missense variants.

  13. Autosomal recessive ataxias: 20 types, and counting Ataxias autossômicas recessivas: 20 tipos e muito mais

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    Emília Katiane Embiruçu

    2009-12-01

    Full Text Available More than 140 years after the first description of Friedreich ataxia, autosomal recessive ataxias have become one of the more complex fields in Neurogenetics. Currently this group of diseases contains more than 20 clinical entities and an even larger number of associated genes. Some disorders are very rare, restricted to isolated populations, and others are found worldwide. An expressive number of recessive ataxias are treatable, and responsibility for an accurate diagnosis is high. The purpose of this review is to update the practitioner on clinical and pathophysiological aspects of these disorders and to present an algorithm to guide the diagnosis.Mais de 140 anos após a primeira descrição da ataxia de Friedreich, as ataxias autossômicas recessivas se transformaram em um dos mais complexos campos da Neurogenética. Atualmente, este grupo de doenças é composto por mais de 20 entidades clínicas e possui um número ainda maior de genes associados. Algumas doenças são muito raras, tendo sido observadas apenas em populações isoladas, enquanto que outras são encontradas no mundo todo. Um número expressivo de ataxias é tratável, e a responsabilidade em se fazer um diagnóstico correto é alta. A finalidade desta revisão é a de atualizar o neurologista a respeito dos principais aspectos clínicos e fisiopatológicos destas doenças e de apresentar um algoritmo para auxiliar a sua investigação e o seu diagnóstico.

  14. Clinical manifestations of autosomal recessive polycystic kidney disease (ARPKD): kidney-related and non-kidney-related phenotypes.

    Science.gov (United States)

    Büscher, Rainer; Büscher, Anja K; Weber, Stefanie; Mohr, Julia; Hegen, Bianca; Vester, Udo; Hoyer, Peter F

    2014-10-01

    Autosomal recessive polycystic kidney disease (ARPKD), although less frequent than the dominant form, is a common, inherited ciliopathy of childhood that is caused by mutations in the PKHD1-gene on chromosome 6. The characteristic dilatation of the renal collecting ducts starts in utero and can present at any stage from infancy to adulthood. Renal insufficiency may already begin in utero and may lead to early abortion or oligohydramnios and lung hypoplasia in the newborn. However, there are also affected children who have no evidence of renal dysfunction in utero and who are born with normal renal function. Up to 30 % of patients die in the perinatal period, and those surviving the neonatal period reach end stage renal disease (ESRD) in infancy, early childhood or adolescence. In contrast, some affected patients have been diagnosed as adults with renal function ranging from normal to moderate renal insufficiency to ESRD. The clinical spectrum of ARPKD is broader than previously recognized. While bilateral renal enlargement with microcystic dilatation is the predominant clinical feature, arterial hypertension, intrahepatic biliary dysgenesis remain important manifestations that affect approximately 45 % of infants. All patients with ARPKD develop clinical findings of congenital hepatic fibrosis (CHF); however, non-obstructive dilation of the intrahepatic bile ducts in the liver (Caroli's disease) is seen at the histological level in only a subset of patients. Cholangitis and variceal bleeding, sequelae of portal hypertension, are life-threatening complications that may occur more often in advanced cases of liver disease. In this review we focus on common and uncommon kidney-related and non-kidney-related phenotypes. Clinical management of ARPKD patients should include consideration of potential problems related to these manifestations.

  15. Whole-exome sequencing identifies LRIT3 mutations as a cause of autosomal-recessive complete congenital stationary night blindness.

    Science.gov (United States)

    Zeitz, Christina; Jacobson, Samuel G; Hamel, Christian P; Bujakowska, Kinga; Neuillé, Marion; Orhan, Elise; Zanlonghi, Xavier; Lancelot, Marie-Elise; Michiels, Christelle; Schwartz, Sharon B; Bocquet, Béatrice; Antonio, Aline; Audier, Claire; Letexier, Mélanie; Saraiva, Jean-Paul; Luu, Tien D; Sennlaub, Florian; Nguyen, Hoan; Poch, Olivier; Dollfus, Hélène; Lecompte, Odile; Kohl, Susanne; Sahel, José-Alain; Bhattacharya, Shomi S; Audo, Isabelle

    2013-01-10

    Congenital stationary night blindness (CSNB) is a clinically and genetically heterogeneous retinal disorder. Two forms can be distinguished clinically: complete CSNB (cCSNB) and incomplete CSNB. Individuals with cCSNB have visual impairment under low-light conditions and show a characteristic electroretinogram (ERG). The b-wave amplitude is severely reduced in the dark-adapted state of the ERG, representing abnormal function of ON bipolar cells. Furthermore, individuals with cCSNB can show other ocular features such as nystagmus, myopia, and strabismus and can have reduced visual acuity and abnormalities of the cone ERG waveform. The mode of inheritance of this form can be X-linked or autosomal recessive, and the dysfunction of four genes (NYX, GRM6, TRPM1, and GPR179) has been described so far. Whole-exome sequencing in one simplex cCSNB case lacking mutations in the known genes led to the identification of a missense mutation (c.983G>A [p.Cys328Tyr]) and a nonsense mutation (c.1318C>T [p.Arg440(∗)]) in LRIT3, encoding leucine-rich-repeat (LRR), immunoglobulin-like, and transmembrane-domain 3 (LRIT3). Subsequent Sanger sequencing of 89 individuals with CSNB identified another cCSNB case harboring a nonsense mutation (c.1151C>G [p.Ser384(∗)]) and a deletion predicted to lead to a premature stop codon (c.1538_1539del [p.Ser513Cysfs(∗)59]) in the same gene. Human LRIT3 antibody staining revealed in the outer plexiform layer of the human retina a punctate-labeling pattern resembling the dendritic tips of bipolar cells; similar patterns have been observed for other proteins implicated in cCSNB. The exact role of this LRR protein in cCSNB remains to be elucidated.

  16. Congenital sensorineural deafness in Australian stumpy-tail cattle dogs is an autosomal recessive trait that maps to CFA10.

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    Susan Sommerlad

    -value = 3.64, as was both coat colour and speckling. Fine mapping was then performed on 45 of these 50 dogs and a further 48 dogs (n = 93. Sequencing candidate gene Sox10 in 6 hearing ASCD, 2 unilaterally deaf ASCD and 2 bilaterally deaf ASCD did not reveal any disease-associated mutations. CONCLUSIONS: Deafness in ASCD is an incompletely penetrant autosomal recessive inherited disease that maps to CFA10.

  17. Highly prevalent LIPH founder mutations causing autosomal recessive woolly hair/hypotrichosis in Japan and the genotype/phenotype correlations.

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    Kana Tanahashi

    Full Text Available Mutations in LIPH cause of autosomal recessive woolly hair/hypotrichosis (ARWH, and the 2 missense mutations c.736T>A (p.Cys246Ser and c.742C>A (p.His248Asn are considered prevalent founder mutations for ARWH in the Japanese population. To reveal genotype/phenotype correlations in ARWH cases in Japan and the haplotypes in 14 Japanese patients from 14 unrelated Japanese families. 13 patients had woolly hair, and 1 patient had complete baldness since birth. An LIPH mutation search revealed homozygous c.736T>A mutations in 10 of the patients. Compound heterozygous c.736T>A and c.742C>A mutations were found in 3 of the patients, and homozygous c.742C>A mutation in 1 patient. The phenotype of mild hypotrichosis with woolly hair was restricted to the patients with the homozygous c.736T>A mutation. The severe phenotype of complete baldness was seen in only 1 patient with homozygous c.742C>A. Haplotype analysis revealed that the alleles containing the LIPH c.736T>A mutation had a haplotype identical to that reported previously, although 4 alleles out of 5 chromosomes containing the LIPH c.742C>A mutation had a different haplotype from the previously reported founder allele. These alleles with c.742C>A are thought to be the third founder LIPH mutation causing ARWH. To accurately determine the prevalence of the founder mutations, we investigated allele frequencies of those mutations in 819 Japanese controls. Heterozygous c.736T>A mutations were found in 13 controls (allele frequency: 0.0079; carrier rate: 0.016, and heterozygous c.742C>A mutations were found in 2 controls (allele frequency: 0.0012; carrier rate: 0.0024. In conclusion, this study confirms the more accurate allele frequencies of the pathogenic founder mutations of LIPH and shows that there is a third founder mutation in Japan. In addition, the present findings suggest that the mutation patterns of LIPH might be associated with hypotrichosis severity in ARWH.

  18. Skeletal muscle, but not cardiovascular function, is altered in a mouse model of autosomal recessive hypophosphatemic rickets

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    Michael J. Wacker

    2016-05-01

    Full Text Available Autosomal recessive hypophosphatemic rickets (ARHR is a heritable disorder characterized by hypophosphatemia, osteomalacia, and poor bone development. ARHR results from inactivating mutations in the DMP1 gene with the human phenotype being recapitulated in the Dmp1 null mouse model which displays elevated plasma fibroblast growth factor 23. While the bone phenotype has been well characterized, it is not known what effects ARHR may also have on skeletal, cardiac, or vascular smooth muscle function, which is critical to understand to treat patients suffering from this condition. In this study, the extensor digitorum longus (EDL- fast-twitch muscle, soleus (SOL- slow-twitch muscle, heart, and aorta were removed from Dmp1 null mice and ex-vivo functional tests were simultaneously performed in collaboration by three different laboratories. Dmp1 null EDL and SOL muscles produced less force than wildtype muscles after normalization for physiological cross sectional area of the muscles. Both EDL and SOL muscles from Dmp1 null mice also produced less force after the addition of caffeine (which releases calcium from the sarcoplasmic reticulum which may indicate problems in excitation contraction coupling in these mice. While the body weights of the Dmp1 null were smaller than wildtype, the heart weight to body weight ratio was higher. However, there were no differences in pathological hypertrophic gene expression compared to wildtype and maximal force of contraction was not different indicating that there may not be cardiac pathology under the tested conditions. We did observe a decrease in the rate of force development generated by cardiac muscle in the Dmp1 null which may be related to some of the deficits observed in skeletal muscle. There were no differences observed in aortic contractions induced by PGF2a or 5-HT or in endothelium-mediated acetylcholine-induced relaxations or endothelium-independent sodium nitroprusside-induced relaxations. In

  19. Missense Mutation in Fam83H Gene in Iranian Patients with Amelogenesis Imperfecta.

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    S Jalal Pourhashemi

    2014-12-01

    Full Text Available Amelogenesis Imperfecta (AI is a disorder of tooth development where there is an abnormal formation of enamel or the external layer of teeth. The aim of this study was to screen mutations in the four most important candidate genes, ENAM, KLK4, MMP20 and FAM83H responsible for amelogenesis imperfect.Geneomic DNA was isolated from five Iranian families with 22 members affected with enamel malformations. The PCR amplifications were typically carried out for amplification the coding regions for AI patients and unaffected family members. The PCR products were subjected to direct sequencing. The pedigree analysis was performed using Cyrillic software.One family had four affected members with autosomal dominant hypocalcified amelogenesis imperfecta (ADHPCAI; pedigree analysis revealed four consanguineous families with 18 patients with autosomal recessive hypoplastic amelogenesis imperfecta (ARHPAI. One non-synonymous single-nucleotide substitution, c.1150T>A, p. Ser 342Thr was identified in the FAM83H, which resulted in ADHCAI. Furthermore, different polymorphisms or unclassified variants were detected in MMP20, ENAM and KLK4.Our results are consistent with other studies and provide further evidence for pathogenic mutations of FAM83H gene. These findings suggest different loci and genes could be implicated in the pathogenesis of AI.

  20. Genetics Home Reference: amelogenesis imperfecta

    Science.gov (United States)

    ... Me Understand Genetics Home Health Conditions amelogenesis imperfecta amelogenesis imperfecta Enable Javascript to view the expand/collapse boxes. Download PDF Open All Close All Description Amelogenesis imperfecta is a disorder of tooth development. This ...

  1. Hereditary palmoplantar keratosis of the Gamborg Nielsen type. Clinical and ultrastructural characteristics of a new type of autosomal recessive palmoplantar keratosis.

    Science.gov (United States)

    Kastl, I; Anton-Lamprecht, I; Gamborg Nielsen, P

    1990-01-01

    A new kind of diffuse palmoplantar keratoderma with autosomal recessive inheritance and without associated symptoms was described in Norrbotten, Sweden by Gamborg Nielsen in 1985. Clinically, it ranges between the less severe dominant Unna-Thost type and the more severe recessive Meleda type, as it is milder than the latter. Skin biopsies of five patients from three different families with this new palmoplantar keratoderma, as well as five obligatory heterozygotes from one family, were investigated ultrastructurally in order to characterize this new entity and to differentiate it from the Meleda type. Several features are common to both autosomal recessive palmoplantar keratoses. They show a broadened granular layer, a transit region consisting of cells with a marginal envelope, and considerable hyperkeratosis. Morphologically, this transformation delay is less pronounced in the Gamborg Nielsen type than in the classical Meleda type. As is typical for ridged skin, both types of palmoplantar keratoses possess composite keratohyaline granules. In contrast to the normal appearance of keratohyaline granules in the Meleda type, the Gamborg Nielsen type also shows qualitative deviations of keratohyaline granules with different degrees of spongiosity and electron density and sometimes with a granular border. It seems that abnormal keratohyaline proteins are synthesized that behave differently. The sudden transformation of a granular into a horny cell is physiologically regulated by different enzymes. A delay in this process may be caused by a mutation that reduces or alters the enzymes concerned. We assume the palmoplantar keratoderma of the Gamborg Nielsen type to be a variant of the heterogeneous group of the Meleda type of palmoplantar keratoderma with autosomal recessive inheritance.

  2. LAMB3 mutations causing autosomal-dominant amelogenesis imperfecta.

    Science.gov (United States)

    Kim, J W; Seymen, F; Lee, K E; Ko, J; Yildirim, M; Tuna, E B; Gencay, K; Shin, T J; Kyun, H K; Simmer, J P; Hu, J C-C

    2013-10-01

    Amelogenesis imperfecta (AI) can be either isolated or part of a larger syndrome. Junctional epidermolysis bullosa (JEB) is a collection of autosomal-recessive disorders featuring AI associated with skin fragility and other symptoms. JEB is a recessive syndrome usually caused by mutations in both alleles of COL17A1, LAMA3, LAMB3, or LAMC2. In rare cases, heterozygous carriers in JEB kindreds display enamel malformations in the absence of skin fragility (isolated AI). We recruited two kindreds with autosomal-dominant amelogenesis imperfecta (ADAI) characterized by generalized severe enamel hypoplasia with deep linear grooves and pits. Whole-exome sequencing of both probands identified novel heterozygous mutations in the last exon of LAMB3 that likely truncated the protein. The mutations perfectly segregated with the enamel defects in both families. In Family 1, an 8-bp deletion (c.3446_3453del GACTGGAG) shifted the reading frame (p.Gly 1149Glufs*8). In Family 2, a single nucleotide substitution (c.C3431A) generated an in-frame translation termination codon (p.Ser1144*). We conclude that enamel formation is particularly sensitive to defects in hemidesmosome/basement-membrane complexes and that syndromic and non-syndromic forms of AI can be etiologically related.

  3. The search for mutations in the gene for the beta subunit of the cGMP phosphodiesterase (PDEB) in patients with autosomal recessive retinitis pigmentosa

    DEFF Research Database (Denmark)

    Riess, O; Noerremoelle, A; Weber, B

    1992-01-01

    including 196 bp of the 5' region of the PDEB gene have been assessed for mutations by using single-strand conformational polymorphism analysis in 14 patients from 13 unrelated families with autosomal recessive retinitis pigmentosa (ARRP). No disease-causing mutations were found in this group of affected...... individuals of seven different ancestries. However, a frequent intronic and two exonic polymorphisms (Leu489----Gln and Gly842----Gly) were identified. Segregation analysis using these polymorphic sites excludes linkage of ARRP to the PDEB gene in a family with two affected children....

  4. Autosomal recessive hyper IgM syndrome associated with activation-induced cytidine deaminase gene in three Turkish siblings presented with tuberculosis lymphadenitis - Case report.

    Science.gov (United States)

    Patiroglu, Turkan; Akar, H Haluk; van der Burg, Mirjam; Unal, Ekrem

    2015-09-01

    The hyper-immunoglobulin M (HIGM) syndrome is a heterogeneous group of genetic disorders characterized by recurrent infections, decreased serum levels of immunoglobulin G (IgG) and IgA, and normal/increased serum levels of IgM. Herein, we describe three Turkish siblings with HIGM syndrome who had a homozygous missense mutation (c.70C>T, p.Arg24Trp) in the activation-induced cytidine deaminase gene which results in autosomal recessive HIGM syndrome. Two of the siblings, sibling 1 and sibling 3, presented with cervical deep abscess and cervical tuberculosis lymphadenitis, respectively.

  5. A novel c.5308_5311delGAGA mutation in Senataxin in a Cypriot family with an autosomal recessive cerebellar ataxia

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    Zamba-Papanicolaou Eleni

    2008-04-01

    Full Text Available Abstract Background Senataxin (chromosome 9q34 was recently identified as the causative gene for an autosomal recessive form of Ataxia (ARCA, termed as Ataxia with Oculomotor Apraxia, type 2 (AOA2 and characterized by generalized incoordination, cerebellar atrophy, peripheral neuropathy, "oculomotor apraxia" and increased alpha-fetoprotein (AFP. Here, we report a novel Senataxin mutation in a Cypriot ARCA family. Methods We studied several Cypriot autosomal recessive cerebellar ataxia (ARCA families for linkage to known ARCA gene loci. We linked one family (909 to the SETX locus on chromosome 9q34 and screened the proband for mutations by direct sequencing. Results Sequence analysis revealed a novel c.5308_5311delGAGA mutation in exon 11 of the SETX gene. The mutation has not been detected in 204 control chromosomes from the Cypriot population, the remaining Cypriot ARCA families and 37 Cypriot sporadic cerebellar ataxia patients. Conclusion We identified a novel SETX homozygous c.5308_5311delGAGA mutation that co-segregates with ARCA with cerebellar atrophy and raised AFP.

  6. Whole-exome sequencing reveals a novel frameshift mutation in the FAM161A gene causing autosomal recessive retinitis pigmentosa in the Indian population.

    Science.gov (United States)

    Zhou, Yu; Saikia, Bibhuti B; Jiang, Zhilin; Zhu, Xiong; Liu, Yuqing; Huang, Lulin; Kim, Ramasamy; Yang, Yin; Qu, Chao; Hao, Fang; Gong, Bo; Tai, Zhengfu; Niu, Lihong; Yang, Zhenglin; Sundaresan, Periasamy; Zhu, Xianjun

    2015-10-01

    Retinitis pigmentosa (RP) is a heterogenous group of inherited retinal degenerations caused by mutations in at least 50 genes. To identify genetic mutations underlying autosomal recessive RP (arRP), we performed whole-exome sequencing study on two consanguineous marriage Indian families (RP-252 and RP-182) and 100 sporadic RP patients. Here we reported novel mutation in FAM161A in RP-252 and RP-182 with two patients affected with RP in each family. The FAM161A gene was identified as the causative gene for RP28, an autosomal recessive form of RP. By whole-exome sequencing we identified several homozygous genomic regions, one of which included the recently identified FAM161A gene mutated in RP28-linked arRP. Sequencing analysis revealed the presence of a novel homozygous frameshift mutation p.R592FsX2 in both patients of family RP-252 and family RP-182. In 100 sporadic Indian RP patients, this novel homozygous frameshift mutation p.R592FsX2 was identified in one sporadic patient ARRP-S-I-46 by whole-exome sequencing and validated by Sanger sequencing. Meanwhile, this homozygous frameshift mutation was absent in 1000 ethnicity-matched control samples screened by direct Sanger sequencing. In conclusion, we identified a novel homozygous frameshift mutations of RP28-linked RP gene FAM161A in Indian population.

  7. Periodontal management and restoration of an amelogenesis imperfecta patient: a case report.

    Science.gov (United States)

    Horowitz, Robert A; Gautam, D K; Karol, Suneet; Kumari, Bindiya

    2014-02-01

    This report describes the treatment of a young male patient diagnosed with amelogenesis imperfecta (AI), a hereditary disorder that affects the enamel of both primary and permanent dentition. For management and rehabilitation, it is crucial to determine the type of AI-hypoplastic, hypomaturation, or hypocalcified. As with this patient, who presented with tricho-dento osseous syndrome, patients may present with associated expression of a syndrome (partial or full) and secondary changes in the periodontium. AI is a serious problem; therefore extensive treatment using a multidisciplinary approach must be instituted, especially if the patient is syndrome-associated.

  8. Defining a new candidate gene for amelogenesis imperfecta: from molecular genetics to biochemistry.

    Science.gov (United States)

    Urzúa, Blanca; Ortega-Pinto, Ana; Morales-Bozo, Irene; Rojas-Alcayaga, Gonzalo; Cifuentes, Víctor

    2011-02-01

    Amelogenesis imperfecta is a group of genetic conditions that affect the structure and clinical appearance of tooth enamel. The types (hypoplastic, hypocalcified, and hypomature) are correlated with defects in different stages of the process of enamel synthesis. Autosomal dominant, recessive, and X-linked types have been previously described. These disorders are considered clinically and genetically heterogeneous in etiology, involving a variety of genes, such as AMELX, ENAM, DLX3, FAM83H, MMP-20, KLK4, and WDR72. The mutations identified within these causal genes explain less than half of all cases of amelogenesis imperfecta. Most of the candidate and causal genes currently identified encode proteins involved in enamel synthesis. We think it is necessary to refocus the search for candidate genes using biochemical processes. This review provides theoretical evidence that the human SLC4A4 gene (sodium bicarbonate cotransporter) may be a new candidate gene.

  9. Recessive Mutations in ACPT, Encoding Testicular Acid Phosphatase, Cause Hypoplastic Amelogenesis Imperfecta.

    Science.gov (United States)

    Seymen, Figen; Kim, Youn Jung; Lee, Ye Ji; Kang, Jenny; Kim, Tak-Heun; Choi, Hwajung; Koruyucu, Mine; Kasimoglu, Yelda; Tuna, Elif Bahar; Gencay, Koray; Shin, Teo Jeon; Hyun, Hong-Keun; Kim, Young-Jae; Lee, Sang-Hoon; Lee, Zang Hee; Zhang, Hong; Hu, Jan C-C; Simmer, James P; Cho, Eui-Sic; Kim, Jung-Wook

    2016-11-03

    Amelogenesis imperfecta (AI) is a heterogeneous group of genetic disorders affecting tooth enamel. The affected enamel can be hypoplastic and/or hypomineralized. In this study, we identified ACPT (testicular acid phosphatase) biallelic mutations causing non-syndromic, generalized hypoplastic autosomal-recessive amelogenesis imperfecta (AI) in individuals from six apparently unrelated Turkish families. Families 1, 4, and 5 were affected by the homozygous ACPT mutation c.713C>T (p.Ser238Leu), family 2 by the homozygous ACPT mutation c.331C>T (p.Arg111Cys), family 3 by the homozygous ACPT mutation c.226C>T (p.Arg76Cys), and family 6 by the compound heterozygous ACPT mutations c.382G>C (p.Ala128Pro) and 397G>A (p.Glu133Lys). Analysis of the ACPT crystal structure suggests that these mutations damaged the activity of ACPT by altering the sizes and charges of key amino acid side chains, limiting accessibility of the catalytic core, and interfering with homodimerization. Immunohistochemical analysis confirmed localization of ACPT in secretory-stage ameloblasts. The study results provide evidence for the crucial function of ACPT during amelogenesis.

  10. Additional case of Marden-Walker syndrome: support for the autosomal-recessive inheritance adn refinement of phenotype in a surviving patient.

    Science.gov (United States)

    Orrico, A; Galli, L; Zappella, M; Orsi, A; Hayek, G

    2001-02-01

    In this report, we present a 14-year-old girl, born to consanguineous parents, who presented with severe mental retardation, hypotonia, short stature, and congenital joint contractures. The craniofacial features were scaphocephaly, thin/long and immobile face, marked hypoplasia of the midface, temporal narrowness, blepharophimosis, palpebral ptosis, and strabismus. The combination of such a distinctive craniofacial appearance and psychomotor retardation allows us to recognize a new case of the Marden-Walker syndrome. Our patient represents one of the rare cases in which consanguineous mating supports the autosomal-recessive pattern of inheritance of this condition. Furthermore, through refining the phenotype of a surviving patient, this report may contribute to a better recognition of this disorder in older affected children.

  11. A new locus for autosomal recessive non-syndromic mental retardation maps to 1p21.1-p13.3.

    Science.gov (United States)

    Uyguner, O; Kayserili, H; Li, Y; Karaman, B; Nürnberg, G; Hennies, Hc; Becker, C; Nürnberg, P; Başaran, S; Apak, M Y; Wollnik, B

    2007-03-01

    Autosomal recessive inheritance of non-syndromic mental retardation (ARNSMR) may account for approximately 25% of all patients with non-specific mental retardation (NSMR). Although many X-linked genes have been identified as a cause of NSMR, only three autosomal genes are known to cause ARNSMR. We present here a large consanguineous Turkish family with four mentally retarded individuals from different branches of the family. Clinical tests showed cognitive impairment but no neurological, skeletal, and biochemical involvements. Genome-wide mapping using Human Mapping 10K Array showed a single positive locus with a parametric LOD score of 4.92 in a region on chromosome 1p21.1-p13.3. Further analyses using polymorphic microsatellite markers defined a 6.6-Mb critical region containing approximately 130 known genes. This locus is the fourth one linked to ARNSMR.

  12. A Missense Mutation in the LIM2 Gene Is Associated with Autosomal Recessive Presenile Cataract in an Inbred Iraqi Jewish Family

    Science.gov (United States)

    Pras, Eran; Levy-Nissenbaum, Etgar; Bakhan, Tangiz; Lahat, Hadas; Assia, Ehud; Geffen-Carmi, Noa; Frydman, Moshe; Goldman, Boleslaw; Pras, Elon

    2002-01-01

    In an inbred Iraqi Jewish family, we have studied three siblings with presenile cataract first noticed between the ages of 20 and 51 years and segregating in an autosomal recessive mode. Using microsatellite repeat markers in close proximity to 25 genes and loci previously associated with congenital cataracts in humans and mice, we identified five markers on chromosome 19q that cosegregated with the disease. Sequencing of LIM2, one of two candidate genes in this region, revealed a homozygous T→G change resulting in a phenylalanine-to-valine substitution at position 105 of the protein. To our knowledge, this constitutes the first report, in humans, of cataract formation associated with a mutation in LIM2. Studies of late-onset single-gene cataracts may provide insight into the pathogenesis of the more common age-related cataracts. PMID:11917274

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

    Science.gov (United States)

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

    2016-01-01

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

  14. Identification and characterization of novel parathyroid-specific transcription factor Glial Cells Missing Homolog B (GCMB) mutations in eight families with autosomal recessive hypoparathyroidism.

    Science.gov (United States)

    Bowl, Michael R; Mirczuk, Samantha M; Grigorieva, Irina V; Piret, Sian E; Cranston, Treena; Southam, Lorraine; Allgrove, Jeremy; Bahl, Shailini; Brain, Caroline; Loughlin, John; Mughal, Zulf; Ryan, Fiona; Shaw, Nick; Thakker, Yogini V; Tiosano, Dov; Nesbit, M Andrew; Thakker, Rajesh V

    2010-05-15

    GCMB is a member of the small transcription factor family GCM (glial cells missing), which are important regulators of development, present in vertebrates and some invertebrates. In man, GCMB encodes a 506 amino acid parathyroid gland-specific protein, mutations of which have been reported to cause both autosomal dominant and autosomal recessive hypoparathyroidism. We ascertained 18 affected individuals from 12 families with autosomal recessive hypoparathyroidism and have investigated them for GCMB abnormalities. Four different homozygous germline mutations were identified in eight families that originate from the Indian Subcontinent. These consisted of a novel nonsense mutation R39X; a missense mutation, R47L in two families; a novel missense mutation, R110W; and a novel frameshifting deletion, I298fsX307 in four families. Haplotype analysis, using polymorphic microsatellites from chromosome 6p23-24, revealed that R47L and I298fsX307 mutations arose either as ancient founders, or recurrent de novo mutations. Functional studies including: subcellular localization studies, EMSAs and luciferase-reporter assays, were undertaken and these demonstrated that: the R39X mutant failed to localize to the nucleus; the R47L and R110W mutants both lost DNA-binding ability; and the I298fsX307 mutant had reduced transactivational ability. In order to gain further insights, we undertook 3D-modeling of the GCMB DNA-binding domain, which revealed that the R110 residue is likely important for the structural integrity of helix 2, which forms part of the GCMB/DNA binding interface. Thus, our results, which expand the spectrum of hypoparathyroidism-associated GCMB mutations, help elucidate the molecular mechanisms underlying DNA-binding and transactivation that are required for this parathyroid-specific transcription factor.

  15. Target gene analyses of 39 amelogenesis imperfecta kindreds.

    Science.gov (United States)

    Chan, Hui-Chen; Estrella, Ninna M R P; Milkovich, Rachel N; Kim, Jung-Wook; Simmer, James P; Hu, Jan C-C

    2011-12-01

    Previously, mutational analyses identified six disease-causing mutations in 24 amelogenesis imperfecta (AI) kindreds. We have since expanded the number of AI kindreds to 39, and performed mutation analyses covering the coding exons and adjoining intron sequences for the six proven AI candidate genes [amelogenin (AMELX), enamelin (ENAM), family with sequence similarity 83, member H (FAM83H), WD repeat containing domain 72 (WDR72), enamelysin (MMP20), and kallikrein-related peptidase 4 (KLK4)] and for ameloblastin (AMBN) (a suspected candidate gene). All four of the X-linked AI families (100%) had disease-causing mutations in AMELX, suggesting that AMELX is the only gene involved in the aetiology of X-linked AI. Eighteen families showed an autosomal-dominant pattern of inheritance. Disease-causing mutations were identified in 12 (67%): eight in FAM83H, and four in ENAM. No FAM83H coding-region or splice-junction mutations were identified in three probands with autosomal-dominant hypocalcification AI (ADHCAI), suggesting that a second gene may contribute to the aetiology of ADHCAI. Six families showed an autosomal-recessive pattern of inheritance, and disease-causing mutations were identified in three (50%): two in MMP20, and one in WDR72. No disease-causing mutations were found in 11 families with only one affected member. We conclude that mutation analyses of the current candidate genes for AI have about a 50% chance of identifying the disease-causing mutation in a given kindred.

  16. Animals deficient in C2Orf71, an autosomal recessive retinitis pigmentosa-associated locus, develop severe early-onset retinal degeneration.

    Science.gov (United States)

    Kevany, Brian M; Zhang, Ning; Jastrzebska, Beata; Palczewski, Krzysztof

    2015-05-01

    Genetic mapping was recently used to identify the underlying cause for a previously uncharacterized cohort of autosomal recessive retinitis pigmentosa cases. Genetic mapping of affected individuals resulted in the identification of an uncharacterized gene, C2Orf71, as the causative locus. However, initial homology searches failed to reveal similarities to any previously characterized protein or domain. To address this issue, we characterized the mouse homolog, BC027072. Immunohistochemistry with a custom polyclonal antibody showed staining localized to the inner segments (IS) of photoreceptor cells, as well as the outer segments (OS) of cone cells. A knockout mouse line (BC(-/-)) was generated and demonstrated that loss of this gene results in a severe, early-onset retinal degeneration. Histology and electron microscopy (EM) revealed disorganized OS as early as 3 weeks with complete loss by 24 weeks of age. EM micrographs displayed packets of cellular material containing OS discs or IS organelles in the OS region and abnormal retinal pigmented epithelium cells. Analyses of retinoids and rhodopsin levels showed retinal degenerations. Although its function remains unknown, this protein appears essential for normal OS development/maintenance and vision in humans and mice. RNAseq data are available in the GEO database under accession: GSE63810.

  17. Clinical Application of Screening for GJB2 Mutations before Cochlear Implantation in a Heterogeneous Population with High Rate of Autosomal Recessive Nonsyndromic Hearing Loss

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    Masoud Motasaddi Zarandy

    2011-01-01

    Full Text Available Clinical application of mutation screening and its effect on the outcome of cochlear implantation is widely debated. We investigated the effect of mutations in GJB2 gene on the outcome of cochlear implantation in a population with a high rate of consanguineous marriage and autosomal recessive nonsyndromic hearing loss. Two hundred and one children with profound prelingual sensorineural hearing loss were included. Forty-six patients had 35delG in GJB2. Speech awareness thresholds (SATs and speech recognition thresholds (SRTs improved following implantation, but there was no difference in performance between patients with GJB2-related deafness versus control (all >0.10. Both groups had produced their first comprehensible words within the same period of time following implantation (2.27 months in GJB2-related deaf versus 2.62 months in controls, =0.22. Although our findings demonstrate the need to uncover unidentified genetic causes of hereditary deafness, they do not support the current policy for genetic screening before cochlear implantation, nor prove a prognostic value.

  18. A missense mutation in ALDH18A1, encoding Delta1-pyrroline-5-carboxylate synthase (P5CS), causes an autosomal recessive neurocutaneous syndrome.

    Science.gov (United States)

    Bicknell, Louise S; Pitt, James; Aftimos, Salim; Ramadas, Ram; Maw, Marion A; Robertson, Stephen P

    2008-10-01

    There are several rare syndromes combining wrinkled, redundant skin and neurological abnormalities. Although phenotypic overlap between conditions has suggested that some might be allelic to one another, the aetiology for many of them remains unknown. A consanguineous New Zealand Maori family has been characterised that segregates an autosomal recessive connective tissue disorder (joint dislocations, lax skin) associated with neurological abnormalities (severe global developmental delay, choreoathetosis) without metabolic abnormalities in four affected children. A genome-screen performed under a hypothesis of homozygosity by descent for an ancestral mutation, identified a locus at 10q23 (Z = 3.63). One gene within the candidate interval, ALDH18A1, encoding Delta1-pyrroline-5-carboxylate synthase (P5CS), was considered a plausible disease gene since a missense mutation had previously been shown to cause progressive neurodegeneration, cataracts, skin laxity, joint dislocations and metabolic derangement in a consanguineous Algerian family. A missense mutation, 2350C>T, was identified in ALDH18A1, which predicts the substitution H784Y. H784 is invariant across all phyla and lies within a previously unrecognised, conserved C-terminal motif in P5CS. In an in vivo assay of flux through this metabolic pathway using dermal fibroblasts obtained from an affected individual, proline and ornithine biosynthetic activity of P5CS was not affected by the H784Y substitution. These data suggest that P5CS may possess additional uncharacterised functions that affect connective tissue and central nervous system function.

  19. SIPA1L3 identified by linkage analysis and whole-exome sequencing as a novel gene for autosomal recessive congenital cataract.

    Science.gov (United States)

    Evers, Christina; Paramasivam, Nagarajan; Hinderhofer, Katrin; Fischer, Christine; Granzow, Martin; Schmidt-Bacher, Annette; Eils, Roland; Steinbeisser, Herbert; Schlesner, Matthias; Moog, Ute

    2015-12-01

    Congenital cataract (CC) is one of the most important causes for blindness or visual impairment in infancy. A substantial proportion of isolated CCs has monogenic causes. The disease is genetically heterogeneous, and all Mendelian modes of inheritance have been reported. We mapped a locus for isolated CC on 19p13.1-q13.2 in a distantly consanguineous German family with two sisters affected by dense white cataracts. Whole-exome sequencing identified a homozygous nonsense variant c.4489C>T (p.(R1497*)) in SIPA1L3 (signal-induced proliferation-associated 1 like 3) in both affected children. SIPA1L3 encodes a GTPase-activating protein (GAP), which interacts with small GTPases of the Rap family via its Rap-GAP-domain. The suggested role of Rap GTPases in cell growth, differentiation and organization of the cytoskeleton in the human lens, and lens-enriched expression of the murine ortholog gene Sipa1l3 in embryonic mice indicates that this gene is crucial for early lens development. Our results provide evidence that sequence variants in human SIPA1L3 cause autosomal recessive isolated CC and give new insight into the molecular pathogenesis underlying human cataracts.

  20. Mutations in CDC14A, Encoding a Protein Phosphatase Involved in Hair Cell Ciliogenesis, Cause Autosomal-Recessive Severe to Profound Deafness.

    Science.gov (United States)

    Delmaghani, Sedigheh; Aghaie, Asadollah; Bouyacoub, Yosra; El Hachmi, Hala; Bonnet, Crystel; Riahi, Zied; Chardenoux, Sebastien; Perfettini, Isabelle; Hardelin, Jean-Pierre; Houmeida, Ahmed; Herbomel, Philippe; Petit, Christine

    2016-06-01

    By genetic linkage analysis in a large consanguineous Iranian family with eleven individuals affected by severe to profound congenital deafness, we were able to define a 2.8 Mb critical interval (at chromosome 1p21.2-1p21.1) for an autosomal-recessive nonsyndromic deafness locus (DFNB). Whole-exome sequencing allowed us to identify a CDC14A biallelic nonsense mutation, c.1126C>T (p.Arg376(∗)), which was present in the eight clinically affected individuals still alive. Subsequent screening of 115 unrelated individuals affected by severe or profound congenital deafness of unknown genetic cause led us to identify another CDC14A biallelic nonsense mutation, c.1015C>T (p.Arg339(∗)), in an individual originating from Mauritania. CDC14A encodes a protein tyrosine phosphatase. Immunofluorescence analysis of the protein distribution in the mouse inner ear showed a strong labeling of the hair cells' kinocilia. By using a morpholino strategy to knockdown cdc14a in zebrafish larvae, we found that the length of the kinocilia was reduced in inner-ear hair cells. Therefore, deafness caused by loss-of-function mutations in CDC14A probably arises from a morphogenetic defect of the auditory sensory cells' hair bundles, whose differentiation critically depends on the proper growth of their kinocilium.

  1. Mutations in the latent TGF-beta binding protein 3 (LTBP3) gene cause brachyolmia with amelogenesis imperfecta.

    Science.gov (United States)

    Huckert, Mathilde; Stoetzel, Corinne; Morkmued, Supawich; Laugel-Haushalter, Virginie; Geoffroy, Véronique; Muller, Jean; Clauss, François; Prasad, Megana K; Obry, Frédéric; Raymond, Jean Louis; Switala, Marzena; Alembik, Yves; Soskin, Sylvie; Mathieu, Eric; Hemmerlé, Joseph; Weickert, Jean-Luc; Dabovic, Branka Brukner; Rifkin, Daniel B; Dheedene, Annelies; Boudin, Eveline; Caluseriu, Oana; Cholette, Marie-Claude; Mcleod, Ross; Antequera, Reynaldo; Gellé, Marie-Paule; Coeuriot, Jean-Louis; Jacquelin, Louis-Frédéric; Bailleul-Forestier, Isabelle; Manière, Marie-Cécile; Van Hul, Wim; Bertola, Debora; Dollé, Pascal; Verloes, Alain; Mortier, Geert; Dollfus, Hélène; Bloch-Zupan, Agnès

    2015-06-01

    Inherited dental malformations constitute a clinically and genetically heterogeneous group of disorders. Here, we report on four families, three of them consanguineous, with an identical phenotype, characterized by significant short stature with brachyolmia and hypoplastic amelogenesis imperfecta (AI) with almost absent enamel. This phenotype was first described in 1996 by Verloes et al. as an autosomal recessive form of brachyolmia associated with AI. Whole-exome sequencing resulted in the identification of recessive hypomorphic mutations including deletion, nonsense and splice mutations, in the LTBP3 gene, which is involved in the TGF-beta signaling pathway. We further investigated gene expression during mouse development and tooth formation. Differentiated ameloblasts synthesizing enamel matrix proteins and odontoblasts expressed the gene. Study of an available knockout mouse model showed that the mutant mice displayed very thin to absent enamel in both incisors and molars, hereby recapitulating the AI phenotype in the human disorder.

  2. Autosomal recessive transmission of a rare KRT74 variant causes hair and nail ectodermal dysplasia: allelism with dominant woolly hair/hypotrichosis.

    Directory of Open Access Journals (Sweden)

    Doroteya Raykova

    Full Text Available Pure hair and nail ectodermal dysplasia (PHNED comprises a heterogeneous group of rare heritable disorders characterized by brittle hair, hypotrichosis, onychodystrophy and micronychia. Autosomal recessive (AR PHNED has previously been associated with mutations in either KRT85 or HOXC13 on chromosome 12p11.1-q14.3. We investigated a consanguineous Pakistani family with AR PHNED linked to the keratin gene cluster on 12p11.1 but without detectable mutations in KRT85 and HOXC13. Whole exome sequencing of affected individuals revealed homozygosity for a rare c.821T>C variant (p.Phe274Ser in the KRT74 gene that segregates AR PHNED in the family. The transition alters the highly conserved Phe274 residue in the coil 1B domain required for long-range dimerization of keratins, suggesting that the mutation compromises the stability of intermediate filaments. Immunohistochemical (IHC analyses confirmed a strong keratin-74 expression in the nail matrix, the nail bed and the hyponychium of mouse distal digits, as well as in normal human hair follicles. Furthermore, hair follicles and epidermis of an affected family member stained negative for Keratin-74 suggesting a loss of function mechanism mediated by the Phe274Ser substitution. Our observations show for the first time that homozygosity for a KRT74 missense variant may be associated with AR PHNED. Heterozygous KRT74 mutations have previously been associated with autosomal dominant woolly hair/hypotrichosis simplex (ADWH. Thus, our findings expand the phenotypic spectrum associated with KRT74 mutations and imply that a subtype of AR PHNED is allelic with ADWH.

  3. An autosomal recessive leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa maps to chromosome 17q24.2-25.3

    Directory of Open Access Journals (Sweden)

    Bouhouche Ahmed

    2012-03-01

    Full Text Available Abstract Background Single-gene disorders related to ischemic stroke seem to be an important cause of stroke in young patients without known risk factors. To identify new genes responsible of such diseases, we studied a consanguineous Moroccan family with three affected individuals displaying hereditary leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa that appears to segregate in autosomal recessive pattern. Methods All family members underwent neurological and radiological examinations. A genome wide search was conducted in this family using the ABI PRISM linkage mapping set version 2.5 from Applied Biosystems. Six candidate genes within the region linked to the disease were screened for mutations by direct sequencing. Results Evidence of linkage was obtained on chromosome 17q24.2-25.3. Analysis of recombination events and LOD score calculation suggests linkage of the responsible gene in a genetic interval of 11 Mb located between D17S789 and D17S1806 with a maximal multipoint LOD score of 2.90. Sequencing of seven candidate genes in this locus, ATP5H, FDXR, SLC25A19, MCT8, CYGB, KCNJ16 and GRIN2C, identified three missense mutations in the FDXR gene which were also found in a homozygous state in three healthy controls, suggesting that these variants are not disease-causing mutations in the family. Conclusion A novel locus for leucoencephalopathy with ischemic stroke, dysmorphic syndrome and retinitis pigmentosa has been mapped to chromosome 17q24.2-25.3 in a consanguineous Moroccan family.

  4. Initial evaluation of hepatic T1 relaxation time as an imaging marker of liver disease associated with autosomal recessive polycystic kidney disease (ARPKD).

    Science.gov (United States)

    Gao, Ying; Erokwu, Bernadette O; DeSantis, David A; Croniger, Colleen M; Schur, Rebecca M; Lu, Lan; Mariappuram, Jose; Dell, Katherine M; Flask, Chris A

    2016-01-01

    Autosomal recessive polycystic kidney disease (ARPKD) is a potentially lethal multi-organ disease affecting both the kidneys and the liver. Unfortunately, there are currently no non-invasive methods to monitor liver disease progression in ARPKD patients, limiting the study of potential therapeutic interventions. Herein, we perform an initial investigation of T1 relaxation time as a potential imaging biomarker to quantitatively assess the two primary pathologic hallmarks of ARPKD liver disease: biliary dilatation and periportal fibrosis in the PCK rat model of ARPKD. T1 relaxation time results were obtained for five PCK rats at 3 months of age using a Look-Locker acquisition on a Bruker BioSpec 7.0 T MRI scanner. Six three-month-old Sprague-Dawley (SD) rats were also scanned as controls. All animals were euthanized after the three-month scans for histological and biochemical assessments of bile duct dilatation and hepatic fibrosis for comparison. PCK rats exhibited significantly increased liver T1 values (mean ± standard deviation = 935 ± 39 ms) compared with age-matched SD control rats (847 ± 26 ms, p = 0.01). One PCK rat exhibited severe cholangitis (mean T1  = 1413 ms), which occurs periodically in ARPKD patients. The observed increase in the in vivo liver T1 relaxation time correlated significantly with three histological and biochemical indicators of biliary dilatation and fibrosis: bile duct area percent (R = 0.85, p = 0.002), periportal fibrosis area percent (R = 0.82, p = 0.004), and hydroxyproline content (R = 0.76, p = 0.01). These results suggest that hepatic T1 relaxation time may provide a sensitive and non-invasive imaging biomarker to monitor ARPKD liver disease.

  5. A new autosomal recessive non-progressive congenital cerebellar ataxia associated with mental retardation, optic atrophy, and skin abnormalities (CAMOS) maps to chromosome 15q24-q26 in a large consanguineous Lebanese Druze Family.

    Science.gov (United States)

    Delague, Valérie; Bareil, Corinne; Bouvagnet, Patrice; Salem, Nabiha; Chouery, Eliane; Loiselet, Jacques; Mégarbané, André; Claustres, Mireille

    2002-03-01

    Congenital cerebellar ataxias are a heterogeneous group of non-progressive disorders characterized by hypotonia and developmental delay followed by the appearance of ataxia, and often associated with dysarthria, mental retardation, and atrophy of the cerebellum. We report the mapping of a disease gene in a large inbred Lebanese Druze family, with five cases of a new form of non-progressive autosomal recessive congenital ataxia associated with optic atrophy, severe mental retardation, and structural skin abnormalities, to a 3.6-cM interval on chromosome 15q24-15q26.

  6. The human intrinsic factor-vitamin B12 receptor, cubilin: molecular characterization and chromosomal mapping of the gene to 10p within the autosomal recessive megaloblastic anemia (MGA1) region

    DEFF Research Database (Denmark)

    Kozyraki, R; Kristiansen, M; Silahtaroglu, A

    1998-01-01

    -5445 on the short arm of chromosome 10. This is within the autosomal recessive megaloblastic anemia (MGA1) 6-cM region harboring the unknown recessive-gene locus of juvenile megaloblastic anemia caused by intestinal malabsorption of cobalamin (Imerslund-Gräsbeck's disease). In conclusion, the present...... molecular and genetic information on human cubilin now provides circumstantial evidence that an impaired synthesis, processing, or ligand binding of cubilin is the molecular background of this hereditary form of megaloblastic anemia. Udgivelsesdato: 1998-May-15...

  7. Do consanguineous parents of a child affected by an autosomal recessive disease have more DNA identical-by-descent than similarly-related parents with healthy offspring? Design of a case-control study

    Directory of Open Access Journals (Sweden)

    Cornel Martina C

    2010-07-01

    Full Text Available Abstract Background The offspring of consanguineous relations have an increased risk of congenital/genetic disorders and early mortality. Consanguineous couples and their offspring account for approximately 10% of the global population. The increased risk for congenital/genetic disorders is most marked for autosomal recessive disorders and depends on the degree of relatedness of the parents. For children of first cousins the increased risk is 2-4%. For individual couples, however, the extra risk can vary from zero to 25% or higher, with only a minority of these couples having an increased risk of at least 25%. It is currently not possible to differentiate between high-and low-risk couples. The quantity of DNA identical-by-descent between couples with the same degree of relatedness shows a remarkable variation. Here we hypothesize that consanguineous partners with children affected by an autosomal recessive disease have more DNA identical-by-descent than similarly-related partners who have only healthy children. The aim of the study is thus to establish whether the amount of DNA identical-by-descent in consanguineous parents of children with an autosomal recessive disease is indeed different from its proportion in consanguineous parents who have healthy children only. Methods/Design This project is designed as a case-control study. Cases are defined as consanguineous couples with one or more children with an autosomal recessive disorder and controls as consanguineous couples with at least three healthy children and no affected child. We aim to include 100 case couples and 100 control couples. Control couples are matched by restricting the search to the same family, clan or ethnic origin as the case couple. Genome-wide SNP arrays will be used to test our hypothesis. Discussion This study contains a new approach to risk assessment in consanguineous couples. There is no previous study on the amount of DNA identical-by-descent in consanguineous

  8. MRI assessment of fetal autosomal recessive polycystic kidney disease%常染色体隐性遗传性多囊肾病胎儿的MRI表现

    Institute of Scientific and Technical Information of China (English)

    董素贞; 朱铭; 钟玉敏; 张弘; 潘慧红

    2014-01-01

    目的 探讨MRI对常染色体隐性遗传性多囊肾病(ARPKD)胎儿的诊断价值.方法 回顾性分析2005年7月至2013年12月间产前超声检查提示异常,然后行MR检查,并经引产后尸解或病理证实的ARPKD胎儿16例.MR扫描序列主要采用稳态自由进动(SSFP)序列、单次激发快速自旋回波(SSTSE)序列和快速加权序列T1WI.将产前MRI、超声表现与引产后尸解或病理结果进行对照分析.结果 16例ARPKD患儿均表现为双侧肾脏体积明显增大,SSTSE序列肾髓质弥漫性高信号小囊肿.11例合并羊水过少,11例合并双肺发育不良,6例合并肝纤维化.11例双肺发育不良和6例肝脏轻度纤维化超声均未提示,肾脏病变超声误诊1例,MRI诊断均正确.结论 MRI诊断胎儿ARPKD具有明显优势,不受羊水量的影响,能准确评价肾脏及肺异常.%Objective To explore the value of MRI on fetal autosomal recessive polycystic kidney disease (ARPKD).Methods Sixteen pregnant women,aged from 28 to 38 years (average 30 years) and with gestation age from 22 to 36 weeks (average 25 weeks) underwent MR scanning with a 1.5 T MR unit within 24 to 48 hours after ultrasound examinations.The imaging sequences included steady-state free-precession (SSFP) sequence,single-shot turbo spin echo (SSTSE) sequence and T1-weighted fast imaging sequence.Prenatal US and MR imaging findings were compared with autopsy or pathological results.Results A total of 16 cases of ARPKD showed bilateral markedly enlarged kidneys and diffuse high signal small cysts in renal medulla on SSTSE sequence.Among the 16 cases,11 cases were with oligohydramnios,1 1 cases were with pulmonary hypoplasia,and 6 cases were with hepatic fibrosis.Eleven cases of pulmonary hypoplasia and 6 cases of hepatic fibrosis were all missed by US.For the diagnosis of the renal anomalies,US missed one case.MRI diagnosis was correct in all these cases.Conclusions MRI shows great advantages on the diagnosis of fetal ARPKD

  9. Inhibitory action of chlorophyllin of autosome recessive lethals induced by irradiation; Accion inhibidora de la clorofilina de letales recesivos autosonicos inducidos por irradiacion

    Energy Technology Data Exchange (ETDEWEB)

    Salceda, V.M.; Pimentel, P.A.E.; Cruces, M.P. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: vmss@nuclear.inin.mx

    2006-07-01

    chlorophyllin on the damage caused by the radiation, it was into accothe presence of lethal and semi lethals autosomal. One observes this way that even without the use of the radiation the semi lethals frequency is diminished when the chlorophyllin is applied, in this case the decrease was significant and although there was decrease in the case of the irradiated group this it was not significant; in the case of the lethal ones it happened the opposite it was not significant in radiation absence on the contrary elevate the frequency of this type of genes, however, before the radiation and with pre-treatment with chlorophyllin this it reduced the frequency of autosomal recessive lethals significantly. This is important because in the case of bound recessive lethals recessive to the sex this doesn't happen. (Author)

  10. Amelogenesis imperfecta: an introduction.

    Science.gov (United States)

    Gadhia, K; McDonald, S; Arkutu, N; Malik, K

    2012-04-27

    Amelogenesis imperfecta (AI) is an inherited disorder that is associated with mutations in five genes (AMEL; ENAM; MMP20; KLK4 and FAM83H) with a wide range of clinical presentations (phenotypes). It affects the structure and appearance of enamel of all teeth, both in the primary and secondary dentition. In this review paper, we look at the epidemiology, classification, aetiology, clinical description and diagnosis of AI. In the following three papers of this series, we aim to describe the role of paediatric dentists, orthodontists and restorative dentists in the clinical management of patients with AI.

  11. Uniparental disomy of chromosome 8 leading to homozygosity of a CYP11B1 mutation in a patient with congenital adrenal hyperplasia: implication for a rare etiology of an autosomal recessive disorder.

    Science.gov (United States)

    Matsubara, Keiko; Kataoka, Naoki; Ogita, Satoko; Sano, Shinichiro; Ogata, Tsutomu; Fukami, Maki; Katsumata, Noriyuki

    2014-01-01

    Congenital adrenal hyperplasia (CAH) is an autosomal recessive disorder that usually results from paternally and maternally transmitted mutations in genes for steroidogenic enzymes. Recent studies on steroid 21-hydroxylase deficiency, the most common form of CAH, have revealed that a small percentage of patients have a non-carrier parent; uniparental disomy (UPD) and de novo mutations were reported as disease-causing mechanisms in these patients. However, it remains unknown whether UPD and de novo mutations underlie other forms of CAH. Here, we report a male patient with steroid 11β-hydroxylase deficiency (11OHD) born to a non-carrier mother. The patient was identified by an elevated 17-hydroxyprogesterone level at a neonatal mass-screening test. His clinical features were comparable to those of previously reported patients with 11OHD. Direct sequencing of CYP11B1 identified a homozygous IVS7+1G>A mutation in the patient, which was not shared by his mother. Comparative genomic hybridization of the patient detected UPD of chromosome 8 [UPD(8)]. Microsatellite analysis indicated non-maternal origin of the UPD(8) and confirmed parentage of other chromosomes. This study shows for the first time that 11OHD can be caused by UPD in the presence of a non-carrier parent. Awareness of such rare cases should improve the accuracy of genetic counseling for families with CAH. Our data support the importance of UPD as an underlying mechanism of autosomal recessive disorders.

  12. Circadian rhythms regulate amelogenesis.

    Science.gov (United States)

    Zheng, Li; Seon, Yoon Ji; Mourão, Marcio A; Schnell, Santiago; Kim, Doohak; Harada, Hidemitsu; Papagerakis, Silvana; Papagerakis, Petros

    2013-07-01

    Ameloblasts, the cells responsible for making enamel, modify their morphological features in response to specialized functions necessary for synchronized ameloblast differentiation and enamel formation. Secretory and maturation ameloblasts are characterized by the expression of stage-specific genes which follows strictly controlled repetitive patterns. Circadian rhythms are recognized as key regulators of the development and diseases of many tissues including bone. Our aim was to gain novel insights on the role of clock genes in enamel formation and to explore the potential links between circadian rhythms and amelogenesis. Our data shows definitive evidence that the main clock genes (Bmal1, Clock, Per1 and Per2) oscillate in ameloblasts at regular circadian (24 h) intervals both at RNA and protein levels. This study also reveals that the two markers of ameloblast differentiation i.e. amelogenin (Amelx; a marker of secretory stage ameloblasts) and kallikrein-related peptidase 4 (Klk4, a marker of maturation stage ameloblasts) are downstream targets of clock genes. Both, Amelx and Klk4 show 24h oscillatory expression patterns and their expression levels are up-regulated after Bmal1 over-expression in HAT-7 ameloblast cells. Taken together, these data suggest that both the secretory and the maturation stages of amelogenesis might be under circadian control. Changes in clock gene expression patterns might result in significant alterations of enamel apposition and mineralization.

  13. The absence of correlations between a clinical classification and ultrastructural findings in amelogenesis imperfecta

    Energy Technology Data Exchange (ETDEWEB)

    Baeckman, B.; Lundgren, T.; Engstroem, E.U.; Falk, L.K.L.; Chabala, J.M.; Levi-Setti, R.; Noren, J.G. (Dept. of Pedodontics, Univ. of Goeteborg (Sweden))

    1993-01-01

    This study was performed to examine whether a clinical classification of different phenotypes of amelogenesis imperfecta could be discernible at the ultrastructural level. 17 primary teeth from 16 children with hypomineralization, hypomaturation, or hypoplastic variants of the disease were collected for histologic studies of the enamel by means of polarized light microscopy, scanning electron microscopy (SEM), and secondary ion mass spectrometry (SIMS). Polarization microscopy showed that the enamel was hypomineralized; in 6 teeth a wavy configuration of the enamel prisms also appeared. Three histomorphologic main types could be discerned. In 10 of the teeth extensive hypermineralization of the bulk of the enamel was found. 1 tooth had an unusually tick enamel with only a thin normally mineralized surface layer. SIMS images showed less pronounced signals from Ca[sup 2+] and Na[sup +], but with stronger signals from Cl[sup -] and CN[sup -], representing the organic component of enamel. The SEM images showed an irregular prism pattern with marked interprismatic areas. Irrespective of the clinical appearance or the herediatary pattern the main findings were hypomineralized enamel with or without wavy bands. Neither of the analytical methods used in this paper distinguishes between the clinical phenotypes of amelogenesis imperfecta. 35 refs., 9 figs., 1 tab.

  14. Localization of a gene for autosomal dominant amelogenesis imperfecta (ADAI) to chromosome 4q

    Energy Technology Data Exchange (ETDEWEB)

    Forsman, K.; Lind. L.; Westermark, E. [Univ. of Umea (Sweden)] [and others

    1994-09-01

    Amelogenesis imperfecta (AI), a disorder affecting the formation of enamel, is significantly more common in Northern Sweden than in other parts of the world. The disease is genetically and clinically heterogenous, and autosomal dominant, autosomal recessive and X-linked inheritance patterns have been recognized. Linkage analysis has identified two different loci for X-linked AI, one of which is identical to the gene encoding the enamel protein amelogenin. However, in families with an autosomal inheritance pattern for AI, the genetic basis of the disease still remains unknown. We report a linkage analysis study performed on three Swedish families where the affected members had an autosomal dominant variant of AI (ADAI) clinically characterized as local hypoplastic. Significant linkage to microsatellite markers on chromosome 4q were obtained, with a maximum lod score of 5.55 for the marker D4S428. Recombinations in the family localized the ADAI locus to the interval between D4S392 and D4S395. This chromosome region contains both a locus for the dental disorder dentinogenesis imperfecta and the albumin gene. Serum albumin has been suggested to play a role in enamel formation, and the albumin gene is therefore a candidate gene for this genetic disease.

  15. Simple recessive mutation in ENAM is associated with amelogenesis imperfecta in Italian Greyhounds.

    Science.gov (United States)

    Gandolfi, Barbara; Liu, Hongwei; Griffioen, Layle; Pedersen, Niels C

    2013-08-01

    We report a familial enamel hypoplasia in Italian Greyhounds resembling non-syndromic autosomal recessive amelogenesis imperfecta (AI) of humans. The condition uniformly affects deciduous and permanent teeth and is manifested by enamel roughening/thinning and brownish mottling. Affected teeth are often small and pointed with increased gaps. However, basic tooth structure is usually maintained throughout life, and fractures and dental cavities are not a serious problem as in humans. No tissues or organs other than teeth were affected by this mutation, and there was no relationship between enamel hypoplasia and either autoimmunity or periodontal disease, which also are prevalent in the breed. The enamel hypoplasia was associated with a 5-bp deletion in exon 10 of the enamelin (ENAM) gene. The prevalence of the enamel defect in Italian Greyhounds was 14%, and 30% of dogs with normal teeth were carriers. Genome analyses suggest that the trait is under inadvertent positive selection. Based on the deletion detected in the ENAM gene, a genetic test was developed for identifying mutation carriers, which would enable breeders to manage the trait.

  16. A neonate with Coombs-negative hemolytic jaundice with spherocytes but normal erythrocyte indices: a rare case of autosomal-recessive hereditary spherocytosis due to alpha-spectrin deficiency.

    Science.gov (United States)

    Yaish, H M; Christensen, R D; Agarwal, A

    2013-05-01

    The diagnosis of hereditary spherocytosis (HS) in a newborn infant is generally made on the basis of a positive family history, spherocytes on blood film and Coombs-negative hemolytic jaundice of variable severity with an elevated mean corpuscular hemoglobin concentration (MCHC) and a low mean corpuscular volume (MCV). In general, sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE) quantification of erythrocyte membrane proteins is not needed to make the clinical diagnosis of HS. However, we observed that a neonate with no family history of HS, but with abundant spherocytosis on repeated blood films, Coombs-negative hemolytic jaundice and normal MCHC and MCV measurements, where SDS-PAGE revealed alpha-spectrin deficiency, a rare autosomal-recessive variety of HS that generally has a severe clinical phenotype.

  17. Microcefalia primária autossômica recessiva em três famílias pernambucanas: aspectos clínicos e moleculares Autosomal recessive primary microcephaly in three families from Pernambuco: clinical and molecular aspects

    Directory of Open Access Journals (Sweden)

    Gabriela F. Leal

    2005-06-01

    Full Text Available OBJETIVOS: descrever os aspectos clínicos de três famílias pernambucanas com microcefalia primária autossômica recessiva e as análises de ligação em uma delas (família 2. MÉTODOS: três famílias consangüíneas pernambucanas, não relacionadas biologicamente, com microcefalia primária, foram estudadas. Os heredogramas e a história clínica dos afetados foram construídos com base em informações obtidas de seus pais e outros parentes. O exame físico foi realizado em todos os afetados, seus genitores e na quase totalidade dos irmãos normais dos afetados. O DNA genômico dos afetados da família 2 e de seus pais foi usado em reações de PCR (polimerase chain reaction com primers elaborados para amplificar marcadores microssatélites ligados aos locos já conhecidos de microcefalia primária autossômica recessiva. Os marcadores amplificados foram submetidos a eletroforese e seus alelos analisados. RESULTADOS: nas três famílias, os afetados apresentavam perímetro cefálico muito reduzido acompanhado de retardo mental e apenas uma paciente (da família 3 manifestava outras alterações neurológicas, mas sem dismorfias associadas. Estudos moleculares demonstraram que a microcefalia, na família 2, não apresentava ligação com nenhum dos locos associados à microcefalia primária autossômica recessiva já conhecidos. CONCLUSÕES: pelo menos mais um gene associado à microcefalia primária autossômica recessiva existe e aguarda identificação.OBJECTIVES: to describe the clinical findings in three families from Pernambuco with autosomal recessive primary microcephaly, and the linkage analysis in one of them (family 2. METHODS: three consanguineous families from Pernambuco, not related one to another and with primary microcephaly, were studied. The genealogical data and the clinical history of the affected individuals were obtained from their parents and other family members. All the affected subjects, almost all their normal

  18. Enamelin (Enam) is essential for amelogenesis: ENU-induced mouse mutants as models for different clinical subtypes of human amelogenesis imperfecta (AI).

    Science.gov (United States)

    Masuya, Hiroshi; Shimizu, Kunihiko; Sezutsu, Hideki; Sakuraba, Yoshiyuki; Nagano, Junko; Shimizu, Aya; Fujimoto, Naomi; Kawai, Akiko; Miura, Ikuo; Kaneda, Hideki; Kobayashi, Kimio; Ishijima, Junko; Maeda, Takahide; Gondo, Yoichi; Noda, Tetsuo; Wakana, Shigeharu; Shiroishi, Toshihiko

    2005-03-01

    Amelogenesis imperfecta (AI) is a group of commonly inherited defects of dental enamel formation, which exhibits marked genetic and clinical heterogeneity. The genetic basis of this heterogeneity is still poorly understood. Enamelin, the affected gene product in one form of AI (AIH2), is an extracellular matrix protein that is one of the components of enamel. We isolated three ENU-induced dominant mouse mutations, M100395, M100514 and M100521, which caused AI-like phenotypes in the incisors and molars of the affected individuals. Linkage analyses mapped each of the three mutations to a region of chromosome 5 that contained the genes encoding enamelin (Enam) and ameloblastin (Ambn). Sequence analysis revealed that each mutation was a single-base substitution in Enam. M100395 (Enam(Rgsc395)) and M100514 (Enam(Rgsc514)) were putative missense mutations that caused S to I and E to G substitutions at positions 55 and 57 of the translated protein, respectively. Enam(Rgsc395) and Enam(Rgsc514) heterozygotes showed severe breakage of the enamel surface, a phenotype that resembled local hypoplastic AI. The M100521 mutation (Enam(Rgsc521)) was a T to A substitution at the splicing donor site in intron 4. This mutation resulted in a frameshift that gave rise to a premature stop codon. The transcript of the Enam(Rgsc521) mutant allele was degraded, indicating that Enam(Rgsc521) is a loss-of-function mutation. Enam(Rgsc521) heterozygotes showed a hypomaturation-type AI phenotype in the incisors, possibly due to haploinsufficiency of Enam. Enam(Rgsc521) homozygotes showed complete loss of enamel on the incisors and the molars. Thus, we report here that the Enam gene is essential for amelogenesis, and that mice with different point mutations at Enam may provide good animal models to study the different clinical subtypes of AI.

  19. Amelogenesis imperfecta: the orthodontic perspective.

    Science.gov (United States)

    Arkutu, N; Gadhia, K; McDonald, S; Malik, K; Currie, L

    2012-05-25

    Orthodontics in patients with amelogenesis imperfecta can be complicated by commonly occurring dental features in this group as well as patient factors. In this article we examine ways to avoid the common pitfalls of orthodontic management and the importance of adequate and timely liaison between the general dental practitioner and the multidisciplinary team.

  20. Kallikrein 4 and amelogenesis imperfecta%激肽释放酶4与釉质发生不全

    Institute of Scientific and Technical Information of China (English)

    王光平; 李明霞; 刘建国

    2013-01-01

      激肽释放酶4(KLK4)在釉质发生的转换期和成熟早期大量表达,水解基质蛋白,降低牙釉蛋白与羟磷灰石的结合,促进釉质晶体的生长和矿化。如果其基因突变或缺失,将导致釉质发生不全。本文就KLK4的结构、KLK4的表达与生物学功能、 KLK4的调控因子、 KLK4与釉质发生不全等研究进展作一综述。%  Kallikrein 4(KLK4) is a protease expressed during the transition and maturation stages of dental enamel formation. KLK4 can degrade enamel proteins, reduce enamel proteins combination to hydroxyapatite, and promote the enamel crystals growth and mineralization. KLK4 mutations or defects cause hypomaturation amelogenesis im-perfecta. This article reviewed the structure, expression, functions, regulatory factors of KLK4 and its effect on amelogenesis imperfecta.

  1. 常染色体隐性遗传性成骨不全症的分子遗传学研究进展%Advances on molecular genetics of autosomal recessive osteogenesis imperfecta

    Institute of Scientific and Technical Information of China (English)

    曹丽华; 张学

    2010-01-01

    成骨不全症(osteogenesis imperfecta,OI)又称脆骨症,由于遗传缺陷而引起Ⅰ型胶原结构或功能异常,表现为全身骨骼等结缔组织异常.临床特点是多发性骨折,同时可伴有巨头畸形、蓝巩膜、耳聋、牙齿改变和脊柱后侧凸等.成骨不全症不仪临床表型变异度大,而且遗传异质性高,以常染色体显件或隐性遗传方式传递,本文就常染色体隐性遗传性成骨不全症的分子遗传学研究进展加以综述.%Osteogenesis imperfecta (OI) , also known as brittle bone disease, is a genetic disorder of connective tissue caused by structural or functional abnormality of type I collagen. OI is characterized by multiple bone fractures. Affected individuals may also have macrocephaly, blue sclerae,hearing loss, dentinogene-sis imperfecta, and kyphoscoliosis. OI shows marked clinical variability and genetic heterogeneity, and both autosomal dominant and recessive forms exist. In this paper, we will review the recent progress in molecular genetics of the autosomal recessive OI.

  2. AMELOGENESIS IMPERFECTA: A CLINICAL REPORT

    Directory of Open Access Journals (Sweden)

    Veena

    2015-01-01

    Full Text Available AIM: This clinical case report describes the oral rehabilitation of a young adult female patient diagnosed with hypoplastic Amelogenesis imperfecta. SUMMARY : Amelogenesis Imperfecta is a hereditary condition that affects the formation of the enamel mineralization process of both the primary and secondary dentition. It is clinically and genetically heterogeneous grou p of condition that affects both the quantity and quality of the enamel structure resulting in extensive loss of tooth tissue , poor esthetics and tooth sensitivity. The main objective for the selected treatment was to enhance the esthetics , and restoring m asticatory function. Treatment was divided into phases which included removal of impacted canine , lengthening of the maxillary and mandibular clinical crowns , and placement of anterior and posterior crowns.

  3. Amelogenesis imperfecta and other biomineralization defects in Fam20a and Fam20c null mice.

    Science.gov (United States)

    Vogel, P; Hansen, G M; Read, R W; Vance, R B; Thiel, M; Liu, J; Wronski, T J; Smith, D D; Jeter-Jones, S; Brommage, R

    2012-11-01

    The FAM20 family of secreted proteins consists of three members (FAM20A, FAM20B, and FAM20C) recently linked to developmental disorders suggesting roles for FAM20 proteins in modulating biomineralization processes. The authors report here findings in knockout mice having null mutations affecting each of the three FAM20 proteins. Both Fam20a and Fam20c null mice survived to adulthood and showed biomineralization defects. Fam20b (-/-) embryos showed severe stunting and increased mortality at E13.5, although early lethality precluded detailed investigations. Physiologic calcification or biomineralization of extracellular matrices is a normal process in the development and functioning of various tissues (eg, bones and teeth). The lesions that developed in teeth, bones, or blood vessels after functional deletion of either Fam20a or Fam20c support a significant role for their encoded proteins in modulating biomineralization processes. Severe amelogenesis imperfecta (AI) was present in both Fam20a and Fam20c null mice. In addition, Fam20a (-/-) mice developed disseminated calcifications of muscular arteries and intrapulmonary calcifications, similar to those of fetuin-A deficient mice, although they were normocalcemic and normophosphatemic, with normal dentin and bone. Fam20a gene expression was detected in ameloblasts, odontoblasts, and the parathyroid gland, with local and systemic effects suggesting both local and/or systemic effects for FAM20A. In contrast, Fam20c (-/-) mice lacked ectopic calcifications but were severely hypophosphatemic and developed notable lesions in both dentin and bone to accompany the AI. The bone and dentin lesions, plus the marked hypophosphatemia and elevated serum alkaline phosphatase and FGF23 levels, are indicative of autosomal recessive hypophosphatemic rickets/osteomalacia in Fam20c (-/-) mice.

  4. A new locus (SPG46) maps to 9p21.2-q21.12 in a Tunisian family with a complicated autosomal recessive hereditary spastic paraplegia with mental impairment and thin corpus callosum.

    Science.gov (United States)

    Boukhris, Amir; Feki, Imed; Elleuch, Nizar; Miladi, Mohamed Imed; Boland-Augé, Anne; Truchetto, Jérémy; Mundwiller, Emeline; Jezequel, Nadia; Zelenika, Diana; Mhiri, Chokri; Brice, Alexis; Stevanin, Giovanni

    2010-10-01

    Hereditary spastic paraplegia (HSP) with thin corpus callosum (TCC) and mental impairment is a frequent subtype of complicated HSP, often inherited as an autosomal recessive (AR) trait. It is clear from molecular genetic analyses that there are several underlying causes of this syndrome, with at least six genetic loci identified to date. However, SPG11 and SPG15 are the two major genes for this entity. To map the responsible gene in a large AR-HSP-TCC family of Tunisian origin, we investigated a consanguineous family with a diagnosis of AR-HSP-TCC excluded for linkage to the SPG7, SPG11, SPG15, SPG18, SPG21, and SPG32 loci. A genome-wide scan was undertaken using 6,090 SNP markers covering all chromosomes. The phenotypic presentation in five patients was suggestive of a complex HSP that associated an early-onset spastic paraplegia with mild handicap, mental deterioration, congenital cataract, cerebellar signs, and TCC. The genome-wide search identified a single candidate region on chromosome 9, exceeding the LOD score threshold of +3. Fine mapping using additional markers narrowed the candidate region to a 45.1-Mb interval (15.4 cM). Mutations in three candidate genes were excluded. The mapping of a novel AR-HSP-TCC locus further demonstrates the extensive genetic heterogeneity of this condition. We propose that testing for this locus should be performed, after exclusion of mutations in SPG11 and SPG15 genes, in AR-HSP-TCC families, especially when cerebellar ataxia and cataract are present.

  5. Rescue of the temperature-sensitive, autosomal-recessive mutation R298S in the sodium-bicarbonate cotransporter NBCe1-A characterized by a weakened dimer and abnormal aggregation

    Science.gov (United States)

    Gill, Harindarpal S.; Choi, Kun-Young; Kammili, Lakshmi; Popratiloff, Anastas

    2015-01-01

    Background Band keratopathy, an ocular disease that is characterized by hypercalcemia and opaque bands across the cornea, has been associated with kidney disease. Type-II renal tubular acidosis (RTA), a condition in which the kidneys fail to recover bicarbonate (HCO3−) in the proximal tubule of the nephron, results in HCO3− wastage in the urine and low blood pH. The development of these diseases is associated with autosomal-recessive mutations in the Na+-coupled HCO3− cotransporter NBCe1-A located at the basolateral membranes of either cell type. Methods We provide insight into the devastating R298S mutation found in type-II RTA-afflicted individuals using confocal-microscopy imaging of fluorescently-tagged NBCe1-A and NBCe1-A-R298S molecules expressed in human corneal endothelial and proximal tubule cells and from in-depth biophysical studies of their cytoplasmic N-terminal domains (Nt and Nt-R298S), including Nt crystal structure, melting-temperature, and homodimer dissociation constant (KD) analyses. Results We illuminate and rescue trafficking defects of the R298S mutation of NBCe1-A. The KD for Nt monomer-dimer equilibrium is established. The KD for Nt-R298S is significantly higher, but immeasurable due to environmental factors (pH, temperature, concentration) that result in dimer instability leading to precipitation. The crystal structure of Nt-dimer shows that R298 is part of a putative substrate conduit and resides near the dimer interface held together by hydrogen-bond networks. Conclusions The R298S is a temperature-sensitive mutation in Nt that results in instability of the colloidal system leading to abnormal aggregation. General significance Our findings provide new perspectives to the aberrant mechanism of certain ocular pathologies and type-II RTA associated with the R298S mutation. PMID:25743102

  6. Aberrant expression pattern of a novel mutation in connexin 26 gene resulting in autosomal recessive deafness%连接蛋白基因一个新致聋突变体p.Y155X及功能分析

    Institute of Scientific and Technical Information of China (English)

    杨中纯; 肖自安; 谢鼎华; 夏昆

    2010-01-01

    Objective To report a novel deafness-causing mutation c. 465T→A, p. Y155X in connexin 26 (CX26) (also called gap junction protein β-2, GJB2 ), and perform functional analysis of the mutated protein p. Y155X in Hela cells to explore the underlying mechanism on deafness. Methods Mutations in CX26 gene of the proband in an autosomal recessive inherited deafness family were tested by direct DNA sequencing method. Mutant p. Y155X, which was found in the deafness family, and wild type CX26 (wtCX26), were directionally subcloned into the pEGFP-N1 plasmid to construct the recombinant fusion protein expression vector of CX26 p. Y155X-EGFP and wtCX26-EGFP, followed by transfecting into HeLa cells. The expression of the mutated and wild type proteins was analyzed using Western blot analysis. The intracellular localization of proteins and the formation of gap junction-like plaques at plasma membrane were observed under confocal microscope. Gap junction coupling was tested by calcein-AM dye transfer experiment. Results A novel nonsense mutation c. 465T→A, p. Y155X in the CX26 gene was found in the autosomal recessive deafness family. The molecular weight of protein p. Y155X was smaller than that of wtCX26 in transiently expressed HeLa cells. The mutated protein failed to reach the cell surface to form gap junction plaques, and displayed cytoplasmic accumulation. Also, no calcein-AM dye was transferred from the donor cells to the recipient cells when both were transfected with CX26 p. Y155X. The wtCX26 protein localized at the cell membrane to form gap junction plaques with permeability to fluorescent dye calcein-AM. Conclusion CX26 p. Y155X could not be targeted to the plasma membrane and there was no formation of gap junction channels between the adjacent cells. The mutation c. 465T→A, p. Y155X in CX26 gene was responsible for the autosomal recessive hearing impairment in this family.%目的 观察连接蛋白(connexin 26,CX26)基因的一个新致聋突变c.465T

  7. Enamel formation and amelogenesis imperfecta.

    Science.gov (United States)

    Hu, Jan C-C; Chun, Yong-Hee P; Al Hazzazzi, Turki; Simmer, James P

    2007-01-01

    Dental enamel is the epithelial-derived hard tissue covering the crowns of teeth. It is the most highly mineralized and hardest tissue in the body. Dental enamel is acellular and has no physiological means of repair outside of the protective and remineralization potential provided by saliva. Enamel is comprised of highly organized hydroxyapatite crystals that form in a defined extracellular space, the contents of which are supplied and regulated by ameloblasts. The entire process is under genetic instruction. The genetic control of amelogenesis is poorly understood, but requires the activities of multiple components that are uniquely important for dental enamel formation. Amelogenesis imperfecta (AI) is a collective designation for the variety of inherited conditions displaying isolated enamel malformations, but the designation is also used to indicate the presence of an enamel phenotype in syndromes. Recently, genetic studies have demonstrated the importance of genes encoding enamel matrix proteins in the etiology of isolated AI. Here we review the essential elements of dental enamel formation and the results of genetic analyses that have identified disease-causing mutations in genes encoding enamel matrix proteins. In addition, we provide a fresh perspective on the roles matrix proteins play in catalyzing the biomineralization of dental enamel.

  8. 常染色体隐性遗传多囊肾病 PKHD1基因检测%Detection of PKHD1 gene in autosomal recessive polycystic kidney disease

    Institute of Scientific and Technical Information of China (English)

    宋红霞; 孙春梅; 韩蓁; 李媛; 周熙惠

    2013-01-01

    Objective To identify and analyze mutation in polycystic kidney and hepatic disease 1 ( PKHD1 ) in one abortion fetus of autosomal recessive polycystic kidney disease ( ARPKD).Methods Genome DNA was extracted from peripheral venous blood sampled from the fetus and his parents .PCR amplification and DNA direct sequencing and other technical means were adopted to perform gene mutation analysis of PKHD1.Results The following DNA sequence variations were found , ISV7+51G>T in intron 7, c.1587T>C(p. N529N) in exon 17, c.3785C>T(p.A1262V) in exon 32, which caused amino acid substitution from Alanine to Valine .Conclusion The variation of PKHD1 sequence may be involved in the pathogenesis of ARPKD .The sequence analysis of PKHD1 gene can be used as an effective method for prenatal diagnosis .%目的对1例引产的常染色体隐性遗传性多囊肾病胎儿的多囊肾/多囊肝病变1基因( PKHD1)进行基因突变鉴定和结果分析。方法采集引产胎儿及其父母外周静脉血,分别提取基因组DNA,应用PCR扩增、DNA直接测序等技术手段对该胎儿及其父母进行PKHD1基因突变分析。结果胎儿PKHD1基因出现几种序列变异:PKHD1基因第7号内含子发生ISV7+51G>T变异;第17号外显子发生c.1587T>C(p.N529N)变异;第32号外显子发生c.3785C>T(p.A1262V)变异,导致编码PKHD1蛋白多肽链第1262号氨基酸由丙氨酸变为缬氨酸。结论 PKHD1基因序列变异可能是常染色体隐性遗传性多囊肾病的病因,PKHD1基因检测可作为产前筛查的有效诊断手段。

  9. Identification of the first multi-exonic WDR72 deletion in isolated amelogenesis imperfecta, and generation of a WDR72-specific copy number screening tool.

    Science.gov (United States)

    Hentschel, Julia; Tatun, Dana; Parkhomchuk, Dmitri; Kurth, Ingo; Schimmel, Bettina; Heinrich-Weltzien, Roswitha; Bertzbach, Sabine; Peters, Hartmut; Beetz, Christian

    2016-09-15

    Amelogenesis imperfecta (AI) is a clinically and genetically heterogeneous disorder of tooth development which is due to aberrant deposition or composition of enamel. Both syndromic and isolated forms exist; they may be inherited in an X-linked, autosomal recessive, or autosomal dominant manner. WDR72 is one of ten currently known genes for recessive isolated AI; nine WDR72 mutations affecting single nucleotides have been described to date. Based on whole exome sequencing in a large consanguineous AI pedigree, we obtained evidence for presence of a multi-exonic WDR72 deletion. A home-made multiplex ligation-dependent probe amplification assay was used to confirm the aberration, to narrow its extent, and to identify heterozygous carriers. Our study extends the mutational spectrum for WDR72 to include large deletions, and supports a relevance of the previously proposed loss-of-function mechanism. It also introduces an easy-to-use and highly sensitive tool for detecting WDR72 copy number alterations.

  10. Homozygosity for a missense mutation in the 67 kDa isoform of glutamate decarboxylase in a family with autosomal recessive spastic cerebral palsy: parallels with Stiff-Person Syndrome and other movement disorders

    Directory of Open Access Journals (Sweden)

    Woods C Geoffrey

    2004-11-01

    Full Text Available Abstract Background Cerebral palsy (CP is an heterogeneous group of neurological disorders of movement and/or posture, with an estimated incidence of 1 in 1000 live births. Non-progressive forms of symmetrical, spastic CP have been identified, which show a Mendelian autosomal recessive pattern of inheritance. We recently described the mapping of a recessive spastic CP locus to a 5 cM chromosomal region located at 2q24-31.1, in rare consanguineous families. Methods Here we present data that refine this locus to a 0.5 cM region, flanked by the microsatellite markers D2S2345 and D2S326. The minimal region contains the candidate gene GAD1, which encodes a glutamate decarboxylase isoform (GAD67, involved in conversion of the amino acid and excitatory neurotransmitter glutamate to the inhibitory neurotransmitter γ-aminobutyric acid (GABA. Results A novel amino acid mis-sense mutation in GAD67 was detected, which segregated with CP in affected individuals. Conclusions This result is interesting because auto-antibodies to GAD67 and the more widely studied GAD65 homologue encoded by the GAD2 gene, are described in patients with Stiff-Person Syndrome (SPS, epilepsy, cerebellar ataxia and Batten disease. Further investigation seems merited of the possibility that variation in the GAD1 sequence, potentially affecting glutamate/GABA ratios, may underlie this form of spastic CP, given the presence of anti-GAD antibodies in SPS and the recognised excitotoxicity of glutamate in various contexts. Table 4 GAD1 single nucleotide substitutions detected on mutation analysis and occurring in sequences submitted to NCBI SNP database and in the literature. This is not a definitive list, but includes those described at the time of the mutational analysis. *Nucleotide positions were not provided by Maestrini et al. [47]. Source SNP position in mRNA, from the translational start site (bp Gene position of SNP(bp Amino acid change (ALappalainen et al. (2002 A(-478Del Exon

  11. Low doses of paraquat and polyphenols prolong life span and locomotor activity in knock-down parkin Drosophila melanogaster exposed to oxidative stress stimuli: implication in autosomal recessive juvenile parkinsonism.

    Science.gov (United States)

    Bonilla-Ramirez, Leonardo; Jimenez-Del-Rio, Marlene; Velez-Pardo, Carlos

    2013-01-10

    Previous studies have shown that polyphenols might be potent neuroprotective agents in Drosophila melanogaster wild type Canton-S acutely or chronically treated with paraquat (PQ), a selective toxin for elimination of dopaminergic (DAergic) neurons by oxidative stress (OS), as model of Parkinson's disease (PD). This study reports for the first time that knock-down (K-D) parkin Drosophila melanogaster (TH-GAL4; UAS-RNAi-parkin) chronically exposed to PQ (0.1-0.25 mM), FeSO(4) (Fe, 0.1mM), deferoxamine (DFO, 0.01 mM) alone or (0.1mM) PQ in combination with polyphenols propyl gallate (PG, 0.1mM) and epigallocathecin gallate (EGCG, 0.1, 0.5mM) showed significantly higher life span and locomotor activity than untreated K-D flies or treated with (1, 5, 20mM) PQ alone. Whilst gallic acid (GA, 0.1, 0.5mM) alone or in the presence of PQ provoked no effect on K-D flies, epicathecin (EC, 0.5mM) only showed a positive effect on prolonging K-D flies' life span. It is shown that PG (and EGCG) protected protocerebral posterolateral 1 (PPL1) DAergic neurons against PQ. Interestingly, the protective effect of low PQ concentrations, DFO and iron might be explained by a phenomenon known as "hormesis." However, pre-fed K-D flies with (0.1mM) PQ for 7 days and then exposed to (0.25 mM) for additional 8 days affect neither survival nor climbing of K-D Drosophila compared to flies treated with (0.25 mM) PQ alone. Remarkably, K-D flies treated with 0.1mM PQ (7 days) and then with (0.25 mM) PQ plus PG (8 days) behaved almost as flies treated with (0.25 mM) PQ. Taken these data suggest that antioxidant supplements that synergistically act with low pro-oxidant stimuli to prolong and increase locomotor activity become inefficient once a threshold of OS has been reached in K-D flies. Our present findings support the notion that genetically altered Drosophila melanogaster as suitable model to study genetic and environmental factors as causal and/or modulators in the development of autosomal

  12. Clinical findings and long-term managements of patients with amelogenesis imperfecta.

    Science.gov (United States)

    Koruyucu, Mine; Bayram, Merve; Tuna, Elif Bahar; Gencay, Koray; Seymen, Figen

    2014-10-01

    The aim of this clinical case series is to present a diagnosis and different treatment methods of patients in different ages with amelogenesis imperfecta (AI) as well as further treatments during a 3-6 years follow-up period. A number of 31 patients (16 female, 15 male with a mean age of 10.77 ± 2.65 years) with AI have been examined for the study group between 2007 and 2010 years. A detailed anamnesis was recorded, followed by a clinical and radiological assessment of oral health. The types of AI classified for each patient according to clinical and radiographic evaluation. The main complaints of patients, presence of dental caries and dental anomalies were noted. Necessary treatments had been planned for the individual cases of AI. A number of 19 patients had hypoplastic (HP) form, and 10 patients showed hypomaturation (HM) form of AI, while one patient showed hypocalcified form of AI and one patient had HM-HP form with taurodontism. Main complaints were chiefly related to dissatisfactory esthetics and dental sensitivity. Caries prevalence index was 93.5%. Mean decayed, missing, filling permanent teeth (DMF) and DMF surface (DMFS) were found as 2.74 ± 1.71 and 6.23 ± 3.99; df (decayed, filling primary teeth) and dfs (decayed, filling primary teeth surface) were found as 3.12 ± 2.85 and 5.24 ± 4.97, respectively. All patients received individual clinical care, including preventive, restorative, and prosthetic treatments. Patients have scheduled for regular follow-up in every 3 months. Composite restorations were used as the most common treatment (25 patients, 80.6%). The treatment plan should be based on patient's age, type of defects and individual needs of the patients. Necessary treatment plan is essential, not only due to functional and aesthetic reasons, but also for the positive psychological impact on young patients.

  13. Aspectos clínicos da doença renal policística autossômica recessiva DRPAR Clinical aspects of autosomal recessive polycystic kidney disease

    Directory of Open Access Journals (Sweden)

    Natasha Favoretto Dias

    2010-09-01

    Full Text Available INTRODUÇÃO: A Doença Renal Policística Autossômica Recessiva (DRPAR é uma causa importante de morbidade e mortalidade pediátricas, com um espectro variável de manifestações clínicas. MÉTODOS: A apresentação e evolução clínica de 25 pacientes (Pts foram analisadas através da revisão de prontuários, aplicando-se os formulários propostos por Guay-Woodford et al. As morbidades associadas à doença foram avaliadas quanto à frequência e à idade de manifestação. RESULTADOS: A idade média de diagnóstico foi de 61,45 meses (0 a 336,5 meses, com distribuição similar entre os sexos (52% dos pts do sexo feminino. Houve histórico familiar da doença em 20% dos casos (5/25, com dois casos de consanguinidade. Na análise inicial, diagnosticou-se hipertensão arterial (HAS em 56% dos Pts (14/25; doença renal crônica estágio > 2 (DRC > 2 em 24% (6/25; infecções do trato urinário (ITU em 40% (10/25 e hipertensão portal (HP em 32% dos casos (8/25. Das ultrassonografias abdominais iniciais, 80% demonstraram rins ecogênicos com cistos grosseiros e 64% detectaram fígado e vias biliares normais. Inibidores da ECA foram utilizados em 36% dos Pts, betabloqueadores em 20%, bloqueadores de canais de cálcio em 28% e diuréticos em 36% dos casos. Na análise final, após um tempo de acompanhamento médio de 152,2 meses (29,8 a 274,9 meses, HAS foi diagnosticada em 76% dos Pts, DRC > 2 em 44%, ITU em 52% e HP em 68%. CONCLUSÃO: As altas morbidade e mortalidade associadas à DRPAR justificam a construção de um banco de dados internacional, visando ao estabelecimento de um tratamento de suporte precoce.INTRODUCTION: Autosomal Recessive Polycystic Kidney Disease (ARPKD is an important pediatric cause of morbidity and mortality, with a variable clinical spectrum. METHODS: The clinical presentation and evolution of 25 patients (Pts were analyzed by clinical record review, according to the forms proposed by Guay-Woodford et al

  14. Multiple unerupted teeth with amelogenesis imperfecta in siblings.

    Science.gov (United States)

    Hegde, Shruthi

    2012-05-01

    Amelogenesis imperfecta encompasses a group of inherited abnormalities that are generally considered to primarily affect the formation and/or calcification of enamel. This case report describes the unusual presentation of amelogenesis imperfecta in siblings as multiple unerupted teeth, multiple pulpal calcifications, and multiple dilacerations of roots along with the defect in the enamel. The intent of our report is to highlight a rare co-occurrence of amelogenesis imperfecta with multiple morphologic alterations in siblings.

  15. Multiple Unerupted Teeth with Amelogenesis Imperfecta in Siblings

    Directory of Open Access Journals (Sweden)

    Shruthi Hegde

    2012-01-01

    Full Text Available Amelogenesis imperfecta encompasses a group of inherited abnormalities that are generally considered to primarily affect the formation and/or calcification of enamel. This case report describes the unusual presentation of amelogenesis imperfecta in siblings as multiple unerupted teeth, multiple pulpal calcifications, and multiple dilacerations of roots along with the defect in the enamel. The intent of our report is to highlight a rare co-occurrence of amelogenesis imperfecta with multiple morphologic alterations in siblings.

  16. Regulation of pH During Amelogenesis.

    Science.gov (United States)

    Lacruz, Rodrigo S; Nanci, Antonio; Kurtz, Ira; Wright, J Timothy; Paine, Michael L

    2010-02-01

    During amelogenesis, extracellular matrix proteins interact with growing hydroxyapatite crystals to create one of the most architecturally complex biological tissues. The process of enamel formation is a unique biomineralizing system characterized first by an increase in crystallite length during the secretory phase of amelogenesis, followed by a vast increase in crystallite width and thickness in the later maturation phase when organic complexes are enzymatically removed. Crystal growth is modulated by changes in the pH of the enamel microenvironment that is critical for proper enamel biomineralization. Whereas the genetic bases for most abnormal enamel phenotypes (amelogenesis imperfecta) are generally associated with mutations to enamel matrix specific genes, mutations to genes involved in pH regulation may result in severely affected enamel structure, highlighting the importance of pH regulation for normal enamel development. This review summarizes the intra- and extracellular mechanisms employed by the enamel-forming cells, ameloblasts, to maintain pH homeostasis and, also, discusses the enamel phenotypes associated with disruptions to genes involved in pH regulation.

  17. Amelogenesis imperfecta and localised aggressive periodontitis: A rare clinical entity

    Directory of Open Access Journals (Sweden)

    Gayatri Gundannavar

    2013-01-01

    Full Text Available This case report presents two female patients whose chief complaint was discoloration of teeth. On careful clinical examination it was found that the patients had features of amelogenesis imperfecta and localised aggressive periodontitis. This article will give an insight of clinical and radiographic features of amelogenesis imperfecta with localised aggressive periodontitis, which is a rare clinical entity.

  18. Amelogenesis imperfecta and localised aggressive periodontitis: A rare clinical entity.

    Science.gov (United States)

    Gundannavar, Gayatri; Rosh, Radhika M; Chandrasekaran, Shoba; Hussain, Ahad M

    2013-01-01

    This case report presents two female patients whose chief complaint was discoloration of teeth. On careful clinical examination it was found that the patients had features of amelogenesis imperfecta and localised aggressive periodontitis. This article will give an insight of clinical and radiographic features of amelogenesis imperfecta with localised aggressive periodontitis, which is a rare clinical entity.

  19. Amelogenesis imperfecta and the treatment plan - interdisciplinary team approach.

    Science.gov (United States)

    Suchancova, B; Holly, D; Janska, M; Stebel, J; Lysy, J; Thurzo, A; Sasinek, S

    2014-01-01

    Amelogenesis imperfecta is a set of hereditary defects representing mainly the development defects of enamel without the presence of whole-body symptoms. Developmental disorders can manifest a complete absence of enamel, which is caused by improper differentiation of ameloblasts. This article describes the diagnosis and treatment of a patient with amelogenesis imperfecta, as well as the need for interdisciplinary cooperation to achieve the best possible morphological, skeletal, functional and aesthetic rehabilitation of the patients with this diagnosis. Furthermore, the article reviews literature dealing with other anomalies occurring in association with amelogenesis imperfect (Fig. 12, Ref. 20).

  20. Amelogenesis imperfecta: review of diagnostic findings and treatment concepts.

    Science.gov (United States)

    Sabandal, Martin M I; Schäfer, Edgar

    2016-09-01

    Mineralization defects like amelogenesis imperfecta are often of hereditary origin. This article reviews the diagnostic findings and summarizes the suggested treatment approaches. Currently, there are no defined therapy recommendations available for patients suffering from amelogenesis imperfecta. The mentioned therapies are more or less equal but no comprehensive therapy recommendation is evident. When treating patients suffering from amelogenesis imperfecta, a comprehensive therapy of almost every dental discipline has to be considered. The earlier the diagnosis of amelogenesis imperfecta is confirmed, the better the outcome is. Optimal treatment approaches consist of early diagnosis and treatment approach and frequent dental recall appointments to prevent progressive occlusal wear or early destruction by caries. Full-mouth prosthetic treatment seems to be the best treatment option.

  1. 三个常染色体隐性遗传早发型帕金森病家系的PARKIN基因研究%A study on PARKIN gene in three pedigrees with autosomal recessive early-onset Parkinson's disease

    Institute of Scientific and Technical Information of China (English)

    金淼; 焦劲松; 顾卫红; 王康; 邹海强; 陈彪; 王国相

    2005-01-01

    目的探讨PARKIN基因与中国人常染色体隐性遗传早发型帕金森病(autosomal recessive early-onset Parkinson's disease, AREP)家系的关系.方法对3个AREP家系的6例患者和23位成员进行系统的临床检查并进行PARKIN基因PCR扩增,产物通过变性高压液相色谱(denaturing high-performance liquid chromatography, DHPLC)进行突变检测,阳性结果标本进行基因测序.结果所有研究对象的PARKIN基因外显子均扩增成功.DHPLC检测和基因测序发现一个家系中存在PARKIN基因杂合Gly284Arg突变,另一个家系中存在PARKIN基因Ser167Asn多态性,且患者均有环境毒物接触史.结论 PARKIN基因杂合Gly284Arg突变在环境因素的协同作用下可能导致发病.PARKIN基因Ser167Asn多态性是帕金森病的易感因素,汞中毒与其共同作用可能导致发病.

  2. Amelogenesis Imperfecta with Coronal Resorption: Report of Three Cases.

    Science.gov (United States)

    Bhatia, Shannu K; Hunter, M Lindsay; Ashley, Paul F

    2015-12-01

    Intracoronal resorption of the permanent dentition in cases of amelogenesis imperfecta (AI) is a rare finding which poses an added complication to the already complex management of this condition. This paper presents three cases of AI associated with delayed eruption of permanent teeth in which asymptomatic intracoronal resorption occurred. CPD/Clinical Relevance: This paper highlights the fact that teeth affected with amelogenesis imperfecta may undergo asymptomatic intracoronal resorption which is only identifiable radiographically.

  3. Enamelin and autosomal-dominant amelogenesis imperfecta.

    Science.gov (United States)

    Hu, J C-C; Yamakoshi, Y

    2003-01-01

    Dental enamel forms as a progressively thickening extracellular layer by the action of proteins secreted by ameloblasts. The most abundant enamel protein is amelogenin, which is expressed primarily from a gene on the X-chromosome (AMELX). The two most abundant non-amelogenin enamel proteins are ameloblastin and enamelin, which are expressed from the AMBN and ENAM genes, respectively. The human AMBN and ENAM genes are located on chromosome 4q13.2. The major secretory products of the human AMELX, AMBN, and ENAM genes have 175, 421, and 1103 amino acids, respectively, and are all post-translationally modified, secreted, and processed by proteases. Mutations in AMELX have been shown to cause X-linked amelogenesis imperfecta (AI), which accounts for 5% of AI cases. Mutations in ENAM cause a severe form of autosomal-dominant smooth hypoplastic AI that represents 1.5%, and a mild form of autosomal-dominant local hypoplastic AI that accounts for 27% of AI cases in Sweden. The discovery of mutations in the ENAM gene in AI kindreds proved that enamelin is critical for proper dental enamel formation and that it plays a role in human disease. Here we review how enamelin was discovered, what is known about enamelin protein structure, post-translational modifications, processing by proteases, and its potentially important functional properties such as its affinity for hydroxyapatite and influence on crystal growth in vitro. The primary structures of human, porcine, mouse, and rat enamelin are compared, and the human enamelin gene, its structure, chromosomal localization, temporal and spatial patterns of expression, and its role in the etiology of amelogenesis imperfecta are discussed.

  4. X-Linked and Autosomal Recessive Alport Syndrome

    DEFF Research Database (Denmark)

    Savige, Judith; Storey, Helen; Il Cheong, Hae

    2016-01-01

    Alport syndrome results from mutations in the COL4A5 (X-linked) or COL4A3/COL4A4 (recessive) genes. This study examined 754 previously- unpublished variants in these genes from individuals referred for genetic testing in 12 accredited diagnostic laboratories worldwide, in addition to all publishe...

  5. X-Linked and Autosomal Recessive Alport Syndrome

    DEFF Research Database (Denmark)

    Savige, Judith; Storey, Helen; Il Cheong, Hae;

    2016-01-01

    , retinopathy, lamellated glomerular basement membrane), variant pathogenicity was assessed using currently-accepted criteria, and variants were examined for gene location, and age at renal failure onset. Results were compared using Fisher's exact test (DNA Stata). Altogether 754 new DNA variants were...

  6. Autosomal recessive limb girdle myasthenia in two sisters.

    Directory of Open Access Journals (Sweden)

    Shankar A

    2002-10-01

    Full Text Available Limb girdle myasthenic syndromes are rare genetic disorders described under the broad heterogeneous group known as congenital myasthenic syndromes and present with mixed features of myasthenia and myopathy. The familial limb girdle myasthenia has been described as one with selective weakness of pectoral and pelvic girdles, showing a positive response to edrophonium chloride. A report of two sisters affected by this disorder is presented.

  7. Seasonal palmar keratoderma in erythropoietic protoporphyria indicates autosomal recessive inheritance.

    Science.gov (United States)

    Holme, S Alexander; Whatley, Sharon D; Roberts, Andrew G; Anstey, Alexander V; Elder, George H; Ead, Russell D; Stewart, M Felicity; Farr, Peter M; Lewis, Helen M; Davies, Nicholas; White, Marion I; Ackroyd, R Simon; Badminton, Michael N

    2009-03-01

    Erythropoietic protoporphyria (EPP) is an inherited disorder that results from partial deficiency of ferrochelatase (FECH). It is characterized clinically by acute photosensitivity and, in 2% of patients, liver disease. Inheritance is usually autosomal dominant with low penetrance but is recessive in about 4% of families. A cross-sectional study of 223 patients with EPP in the United Kingdom identified six individuals with palmar keratoderma. We now show that these and three additional patients, from six families, have an inherited subtype of EPP which is characterized by seasonal palmar keratoderma, relatively low erythrocyte protoporphyrin concentrations, and recessive inheritance. No patient had evidence of liver dysfunction; four patients had neurological abnormalities. Patients were hetero- or homoallelic for nine different FECH mutations; four of which were previously unreported. Prokaryotic expression predicted that FECH activities were 2.7-25% (mean 10.6%) of normal. Neither mutation type nor FECH activity provided an explanation for the unusual phenotype. Our findings show that palmar keratoderma is a clinical indicator of recessive EPP, identify a phenotype that occurs in 38% of reported families with recessive EPP that to our knowledge is previously unreported, and suggest that patients with this phenotype may carry a lower risk of liver disease than other patients with recessive EPP.

  8. Spectrum of Autosomal Recessive Congenital Ichthyosis in Scandinavia

    DEFF Research Database (Denmark)

    Hellström Pigg, Maritta; Bygum, Anette; Gånemo, Agneta;

    2016-01-01

    -100%). A scoring (0-4) of ichthyosis/ery-thema past infancy showed widely different mean values in the subgroups: HI (3.2/3.1), LI (2.4/0.6), CIE (1.8/1.6), PI (1.1/0.3). Novel or recurrent mutations were found in 113 patients: TGM1 (n = 56), NIPAL4 (n = 15), ALOX12B (n = 15), ABCA12 (n = 8), ALOXE3 (n = 9), SLC27...

  9. Genetics Home Reference: autosomal recessive hyper-IgE syndrome

    Science.gov (United States)

    ... attacks the body's own tissues and organs, causing autoimmune disease. For example, autoimmunity can lead to abnormal destruction of red blood cells (hemolytic anemia ) in people with AR-HIES. AR-HIES is ...

  10. Interdisciplinary approach to oral rehabilitation of patient with amelogenesis imperfecta.

    Science.gov (United States)

    Yilmaz, Burak; Oz, Ulas; Yilmaz, Hasan Guney

    2014-03-01

    Amelogenesis imperfecta is a hereditary condition that affects the development of enamel, causing quantity, structural and compositional anomalies that involve all dentitions. Consequently, the effects can extend to both the primary and secondary dentitions. Patients with amelogenesis imperfecta may present with clinical difficulties, such as insufficient crown length, tooth sensitivity and orthodontic discrepancies, all of which can be resolved successfully with an interdisciplinary approach. This case report describes the interdisciplinary approach to the treatment of a 22-year-old patient with amelogenesis imperfecta. The proper alignment of anterior teeth and gingivo-cervical line was provided with orthodontic and periodontal treatments. All-ceramic crowns were placed on anterior, and metal-ceramic restorations were placed on posterior teeth to reduce sensitivity and improve esthetics with function. Improved esthetic appearance, reduced tooth sensitivity and the resolution of a potentially harmful psychosocial condition were achieved. Patient remained satisfied in the 12-month follow-up examination.

  11. Differential expression of syndecan isoforms during mouse incisor amelogenesis.

    Science.gov (United States)

    Muto, Taro; Miyoshi, Keiko; Munesue, Seiichi; Nakada, Hiroshi; Okayama, Minoru; Matsuo, Takashi; Noma, Takafumi

    2007-08-01

    Syndecans are transmembranous heparan sulfate proteoglycans (HSPGs) with covalently attached glycosaminoglycan side-chains located on the cell surface. The mammalian syndecan family is composed of four types of syndecans (syndecan-1 to -4). Syndecans interact with the intracellular cytoskeleton through the cytoplasmic domains of their core proteins and membrane proteins, extracellular enzymes, growth factors, and matrix components, through their heparan-sulfate chains, to regulate developmental processes.Here, as a first step to assess the possible roles of syndecan proteins in amelogenesis, we examined the expression patterns of all syndecan isoforms in continuously growing mouse incisors, in which we can overview major differentiation stages of amelogenesis at a glance. Understanding the expression domain of each syndecan isoform during specific developmental stages seems useful for investigating their physiological roles in amelogenesis. Immunohistochemical analysis of syndecan core proteins in the lower incisors from postnatal day 1 mice revealed spatially and temporally specific expression patterns, with syndecan-1 expressed in undifferentiated epithelial and mesenchymal cells, and syndecan-2, -3, and -4 in more differentiated cells. These findings suggest that each syndecan isoform functions distinctly during the amelogenesis of the incisors of mice.

  12. Deletion of ameloblastin exon 6 is associated with amelogenesis imperfecta.

    Science.gov (United States)

    Poulter, James A; Murillo, Gina; Brookes, Steven J; Smith, Claire E L; Parry, David A; Silva, Sandra; Kirkham, Jennifer; Inglehearn, Chris F; Mighell, Alan J

    2014-10-15

    Amelogenesis imperfecta (AI) describes a heterogeneous group of inherited dental enamel defects reflecting failure of normal amelogenesis. Ameloblastin (AMBN) is the second most abundant enamel matrix protein expressed during amelogenesis. The pivotal role of AMBN in amelogenesis has been confirmed experimentally using mouse models. However, no AMBN mutations have been associated with human AI. Using autozygosity mapping and exome sequencing, we identified genomic deletion of AMBN exon 6 in a second cousin consanguineous family with three of the six children having hypoplastic AI. The genomic deletion corresponds to an in-frame deletion of 79 amino acids, shortening the protein from 447 to 368 residues. Exfoliated primary teeth (unmatched to genotype) were available from family members. The most severely affected had thin, aprismatic enamel (similar to that reported in mice homozygous for Ambn lacking exons 5 and 6). Other teeth exhibited thicker but largely aprismatic enamel. One tooth had apparently normal enamel. It has been suggested that AMBN may function in bone development. No clinically obvious bone or other co-segregating health problems were identified in the family investigated. This study confirms for the first time that AMBN mutations cause non-syndromic human AI and that mouse models with disrupted Ambn function are valid.

  13. Rehabilitation of amelogenesis imperfecta using a reorganized approach: a case report.

    Science.gov (United States)

    Chan, Kingsley H C; Ho, Edward H T; Botelho, Michael G; Pow, Edmond H N

    2011-05-01

    Amelogenesis imperfecta is a genetic disorder that causes defective enamel development in both the primary and permanent dentitions. Significant tooth structure damage often results in various pulpal symptoms, occlusal disharmony, impaired function, and esthetic disfigurement. These problems pose great challenges to the clinician when rehabilitating patients with amelogenesis imperfecta. This case report describes an uncomplicated and logical way to reorganize, temporize, and completely restore an extensively damaged dentition caused by amelogenesis imperfecta.

  14. Amelogenesis imperfecta and anterior open bite: Etiological, classification, clinical and management interrelationships.

    Science.gov (United States)

    Alachioti, Xanthippi Sofia; Dimopoulou, Eleni; Vlasakidou, Anatoli; Athanasiou, Athanasios E

    2014-01-01

    Although amelogenesis imperfecta is not a common dental pathological condition, its etiological, classification, clinical and management aspects have been addressed extensively in the scientific literature. Of special clinical consideration is the frequent co-existence of amelogenesis imperfecta with the anterior open bite. This paper provides an updated review on amelogenesis imperfecta as well as anterior open bite, in general, and documents the association of these two separate entities, in particular. Diagnosis and treatment of amelogenesis imperfecta patients presenting also with anterior open bite require a lengthy, comprehensive and multidisciplinary approach, which should aim to successfully address all dental, occlusal, developmental, skeletal and soft tissue problems associated with these two serious clinical conditions.

  15. Characterization of the nanoscratch, microstructure, and composition in hypoplastic amelogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Ping Qing

    2015-07-01

    Full Text Available Hypoplastic amelogenesis imperfecta is a widespread hereditary disease that causes the loss of enamel. The purpose of this study was to investigate the nanoscratch resistance of hypoplastic amelogenesis imperfecta for providing a reference for restorative treatment. Four unerupted third molars from a patient diagnosed with hypoplastic amelogenesis imperfecta and seven unerupted third molars from normal individuals were compared. Atomic force microscopy and energy-dispersive X-ray spectroscopy were used to observe the microstructure and composition of the teeth (enamel and dentin. The nanoscratch tests of teeth (enamel and dentin were investigated using a nanoscratch tester, scanning electron microscopy, and a stylus profilometer. The results indicated that hypoplastic amelogenesis imperfecta teeth had different microstructures compared to normal teeth. Hypoplastic amelogenesis imperfecta demonstrated a higher composition of organic substance. Meanwhile, the friction coefficient of hypoplastic amelogenesis imperfecta was higher than that of normal teeth, and inferior frictional resistance of hypoplastic amelogenesis imperfecta teeth was observed. The main damaging mechanisms observed in hypoplastic amelogenesis imperfecta under nanoscratch were the combination of delamination, debris, and cracks in enamel with delamination, debris, and plastic deformation in dentin. Our findings suggested that new dental restorative materials should be selected to match the mechanical properties of hypoplastic amelogenesis imperfecta.

  16. 应用SYBR GreenⅠ实时荧光定量聚合酶链反应检测常染色体隐性遗传早发性帕金森综合征的parkin基因外显子重排突变%Analysis of exon rearrangements in the parkin gene in patients with autosomal recessive early-onset parkinsonism using SYBR Green Ⅰ Real-time PCR

    Institute of Scientific and Technical Information of China (English)

    唐北沙; 严新翔; 聂利珞; 郭纪锋; 张海南; 张学伟; 王磊; 沈璐; 江泓; 夏昆

    2009-01-01

    目的 建立应用SYBR GreenⅠ实时荧光定量聚合酶链反应(Real-time PCR,RT-PCR)检测parkin基因外显子重排突变的技术平台,应用该技术对常染色体隐性遗传早发型帕金森综合征(autosomal recessive early-onset parkinsonism,AREP) 家系进行parkin基因外显子重排突变分析.方法 应用SYBR GreenⅠRT-PCR技术对32个中国AREP家系进行parkin基因外显子重排突变分析.结果 14个家系先证者存在parkin基因外显子重排突变,其中3个为纯合缺失突变、3个为复杂杂合缺失突变和8个杂合缺失突变,未发现外显子重复突变,突变主要累及第2~4号外显子.结论 建立了应用SYBR GreenⅠRT-PCR技术检测parkin基因外显子重排突变的基因检测平台;中国AREP 家系的parkin基因外显子重排突变频率为43.8%,与国外报道相似.%Objective To develop a method of detection exon rearrangements in the parkin gene (PARK2) using SYBR Green Ⅰ real-time PCR and to analyze PARK2 exon rearrangement mutations in families with autosomal recessive early-onset parkinsonism (AREP) using this method. Methods Exon rearrangement in PARK2 was screened by SYBR Green Ⅰ real-time PCR in 32 families with AREP. Results Exon rearrangement mutations were found in 14 families, including 3 compound heterozygous deletions;3 homozygous deletions;and 8 heterozygous deletions. No duplication mutation was found. Hotspot for exon rearrangements clustered in exons 2 through 4. Conclusions We have developed a gene test method using SYBR Green Ⅰ Real-time PCR to detect exon rearrangements in the gene PARK2. The frequency of PARK2 mutation is 43.8% in Chinese families with AREP. This frequency is similar to reported findings in other countries.

  17. 常染色体隐性遗传的类Duchenne肌营养不良临床特征及其发生比率的估计值分析%The Proportion and Clinical Feature of Duchenne Muscular Dystrophy With Autosomal Recessive Inheritance

    Institute of Scientific and Technical Information of China (English)

    麻宏伟; 武盈玉; 王阳; 高薇; 薛燕宁

    2001-01-01

    目的:探讨常染色体隐性遗传的类杜氏肌营养不良(类DMD)临床特点及其在杜氏肌营养不良症(DMD)中的比例。方法:研究8个家系中9例女性类DMD的临床表现、家族史及血清肌酸激酶水平,并估计常染色体隐性遗传的类DMD在DMD中的比例。结果:常染色体隐性遗传的类DMD患者独立行走的平均时间为(1.47±1.00)岁,症状出现的平均时间为(8.11±4.32)岁,血清肌酸激酶平均水平为(2785.10±1500.29)U/L,这种常染色体隐性遗传型类DMD占DMD的9.4%。结论:常染色体隐性遗传的类DMD与DMD在临床上无法区别,部分被认为是性连锁隐性遗传的DMD,实际上是常染色体隐性遗传的类DMD。%Objective:Our aim was to investigate the proportion of autosomal recessive (AR) inheritance among families with patients with Duchenne muscular dystrophy (DMD) and clinical feature in patients with AR form of DMD. Methods:A total of 193 families was studied, 8 of them with at least one girl with “DMD - like” phenotype and 185 with only boys with this kind of phenotype. Based on the number of families with at least one affected girl and the number of patients per sibship among these pedigrees, the proportion of families with DMD inherited as an AR trait was estimated. The clinical examination, family history and serum creatine-kinase were studied in 11 patients diagnosed as AR form of DMD. Results: The proportion of families with AR form of DMD was estimated as 9.4%. The average age of being able to walk is (1.47±1.00) year, serum creatine-kinase levels were (2785.10±1500.29) U/L. The clinical symptom occurred at the average age of (8.11±4.32) year in patients with AR form of DMD. Conclusion: The AR form of muscular dystrophy and DMD not be distingushed clinically. Some families with only affected boys diagnosed as typical DMD, in fact, have the AR form of the disease. This study is very useful for genetic consulting.

  18. Minimally invasive rehabilitation of a patient with amelogenesis imperfecta

    OpenAIRE

    Büchi, Dominik; Fehmer, Vincent; Sailer, Irena; Wolleb, Karin; Jung, Ronald

    2014-01-01

    This case report describes a minimally invasive step-by-step approach to treat a patient with amelogenesis imperfecta. This is a genetic developmental disorder of the dental enamel, which clinically manifests as white and dark discolorations of the teeth. The clinical examination did not reveal the true depth of the staining. Therefore, a step-wise treatment approach was chosen. The first step consisted of a home bleaching procedure, which led to a slight improvement of the esthetic appearanc...

  19. Immediate Desensitization in Teeth Affected by Amelogenesis Imperfecta

    OpenAIRE

    Moreira,Rudá França; Figueiredo,Rossana Gomes; Oliveira,Henrique Eduardo de; Fonseca,Ana Christina Lamosa da; Miranda,Mauro Sayão de

    2016-01-01

    Abstract The aim of this paper was to describe a clinical case of immediate dental desensitization using a self-etch adhesive system in an adolescent patient diagnosed with amelogenesis imperfecta (AI). AI was associated with severe tooth sensitivity, treated by the application of a universal adhesive system for desensitization of the teeth affected by AI. Reduction of tooth sensitivity was assessed using a visual analog scale during all reevaluations. The technique was effective for reducing...

  20. Literature review of amelogenesis imperfecta with case report

    Directory of Open Access Journals (Sweden)

    Sumathy C Chanmougananda

    2012-01-01

    Full Text Available Amelogenesis impertecta (Al is a diverse collection of inherited diseases that exhibit qualitative or quantitative tooth enamel defects in the absence of systemic manifestations. Also known by varied names, such as hereditary enamel dysplasia, hereditary brown opalescent teeth, this defect is entirely ectodermal, since mesodermal components of the teeth are basically normal. This article details a case of Al along with complete review which presents in his twin siblings with clinical, radiological and histopathological report.

  1. Early restorative rehabilitation of children and adolescents with amelogenesis imperfecta

    OpenAIRE

    Pousette Lundgren, Gunilla

    2015-01-01

    Amelogenesis imperfecta (AI) is a rare, genetically determined defect in enamel mineralization. Patients with (AI) can present with rapid tooth loss or fractures of enamel and dental sensitivity as well as alterations in enamel thickness, color, and shape. These factors may compromise esthetic appearance and masticatory function. Existing treatment recommendations suggest using resin composite restorations until adulthood, although such restorations have a limited longevity. The mai...

  2. Amelogenesis Imperfecta - An account of Three Generations affected in a Family

    Directory of Open Access Journals (Sweden)

    G Sarat

    2004-01-01

    Full Text Available Amelogenesis Imperfecta is a hereditary condition affecting dental enamel without any systemic manifestation. This condition can be inherited as either Autosomal or X-linked. In this case report, we discuss with the help of Pedigree Analysis, an account of three generations in a family affected by Autosomal Dominant, Hypoplastic type of Amelogenesis Imperfecta.

  3. Exon rearrangement analysis of parkin gene in patients with autosomal recessive early-onset parkinsonism using fluorescent semi-quantitative PCR%应用荧光半定量聚合酶链反应方法检测常染色体隐性遗传早发性帕金森综合征parkin基因外显子重排突变分析

    Institute of Scientific and Technical Information of China (English)

    郭纪锋; 蔡芳; 潘乾; 沈璐; 江泓; 唐北沙; 夏昆; 严新翔; 张玉虎; 陈涛; 李静; 张学伟; 曹立

    2006-01-01

    目的探讨常染色体隐性遗传早发性帕金森综合征(autosomal recessive early-onset parkinsonism,AREP)parkin基因外显子重排突变情况.方法应用荧光半定量聚合酶链反应(PCR)方法对18个AREP家系进行parkin基因外显子重排突变分析.结果9个AREP家系含有parkin基因外显子重排突变,其中2个家系为外显子4纯合缺失,2个家系为外显子4杂合缺失,2个家系为外显子2杂合缺失,1家系为外显子3杂合缺失,1家系为外显子1杂合缺失,此外,1家系为外显子3和外显子4的复合杂合缺失.未见parkin基因外显子重复突变.结论我国AREP患者存在parkin基因外显子重排突变;parkin基因外显子重排突变可能是我国AREP患者的主要致病因素.

  4. CYBA突变所致儿童常染色体隐性遗传性慢性肉芽肿病二例临床特点和突变分析%Clinical features and molecular analysis of 2 Chinese children with autosomal recessive chronic granulomatous disease caused by CYBA mutations

    Institute of Scientific and Technical Information of China (English)

    贺建新; 赵顺英; 徐保平; 胡英惠; 申昆玲; 江载芳

    2011-01-01

    Objective To summarize clinical and molecular features of two children with autosomal recessive chronic granulomatous disease caused by CYBA mutations.Method The clinical records and CYBA mutations were reviewed for analysis of infections and inflammatory complications.Result The first case was a girl diagnosed with "liver and spleen abscess" in our hospital when she was 2.9 years old,with past history of neonatal impetigo and recurrent purulent lymphadenitis and positive family history.The results of DHR123 flow-cytometry showed that positive phagocytes after phorbol ester (PMA) stimulation was 84.63%.CYBA mutation analysis showed that she had heterozygous 35C > T,Q3X and IVS-2A > G.The second case was a boy diagnosed with" sepsis (salmonella D)" when he was 4 years old with a past history of impetigo,sepsis,perianal abscess,skin infection and positive family history.The results of flowcytometry showed that positive phagocytes after PMA stimulation was 96.13%.CYBA mutation analysis showed that he had homozygous 35C > T,Q3X and his parents were all carriers.All of them had BCG related axillary lymphnode calcification.Conclusion A22CGD cases had recurrent purulent infections (skin,lymphnode,liver and spleen,lung,blood),DHR123 flowcytometric analysis helped the diagnosis of CGD,CYBA mutation analysis ascertained the diagnosis of A22CGD.%目的 报道2例由细胞色素b,α亚单位(CYBA)突变所致常染色体隐性遗传性慢性肉芽肿病(A22CGD)患儿的临床表现及基因突变特点.方法 针对经DHR123流式细胞分析和CYBA基因突变分析明确诊断的2例A22CGD患儿,回顾其临床资料,总结与感染及炎症并发症相关的临床特点.结果 例1,女,2岁11个月,以肝脾脓肿入院,既往有新生儿脓疱疹,反复化脓性淋巴结炎病史.有2例同胞兄长生后早期高热夭折病史.DHR123流式细胞分析结果示佛波酯(PMA)刺激后阳性吞噬细胞为84.61%.CYBA基因突变分析为杂合的35T>C,Q3X

  5. The dynamics of DNA methylation and hydroxymethylation during amelogenesis.

    Science.gov (United States)

    Yoshioka, Hirotaka; Minamizaki, Tomoko; Yoshiko, Yuji

    2015-11-01

    Amelogenesis is a multistep process that relies on specific temporal and spatial signaling networks between the dental epithelium and mesenchymal tissues. Epigenetic modifications of key developmental genes in this process may be closely linked to a network of molecular events. However, the role of epigenetic regulation in amelogenesis remains unclear. Here, we have uncovered the spatial distributions of 5-methylcytosine (5-mC) and 5-hydroxymethylcytosine (5-hmC) to determine epigenetic events in the mandibular incisors of mice. Immunohistochemistry and dot blotting showed that 5-hmC in ameloblasts increased from the secretory stage to the later maturation stage. We also demonstrated the distribution of 5-mC-positive ameloblasts with punctate nuclear labeling from sometime after the initiation of the secretory stage to the later maturation stage; however, dot blotting failed to detect this change. No obvious alteration of 5-mC/5-hmC staining in odontoblasts and dental pulp cells was observed. Concomitant with quantitative expression data, immunohistochemistry showed that maintenance DNA methyltransferase DNMT1 was highly expressed in immature dental epithelial cells and subsequently decreased at later stages of development. Meanwhile, de novo DNA methyltransferase Dnmt3a and Dnmt3b and DNA demethylase Tet family genes were universally expressed, except Tet1 that was highly expressed in immature dental epithelial cells. Thus, DNMT1 may sustain the undifferentiated status of dental epithelial cells through the maintenance of DNA methylation, while the hydroxylation of 5-mC may occur through the whole differentiation process by TET activity. Taken together, these data indicate that the dynamic changes of 5-mC and 5-hmC may be critical for the regulation of amelogenesis.

  6. Crown lengthening procedure in the management of amelogenesis imperfecta

    Science.gov (United States)

    Kalaivani, S.; Manohar, Jenish; Shakunthala, P.; Sujatha, S.; Rajasekaran, S. A.; Karthikeyan, B.; Kalaiselvan, S.

    2015-01-01

    Full mouth rehabilitation includes a promising treatment planning and execution thus fulfilling esthetic, occlusal, and functional parameters maintaining the harmony of the stomatognathic system. Crown lengthening procedures have become an integral component of the esthetic armamentarium and are utilized with increasing frequency to enhance the appearance of restorations placed in the esthetic zone. Crown lengthening plays a role to create healthy relationship of the gingiva and bone levels so as to gain access to more of the tooth which can be restored, if it is badly worn, decayed or fractured, below the gum line. This paper highlights the full mouth crown lengthening procedure performed on a patient with amelogenesis imperfecta. PMID:26538965

  7. Crown lengthening procedure in the management of amelogenesis imperfecta.

    Science.gov (United States)

    Kalaivani, S; Manohar, Jenish; Shakunthala, P; Sujatha, S; Rajasekaran, S A; Karthikeyan, B; Kalaiselvan, S

    2015-08-01

    Full mouth rehabilitation includes a promising treatment planning and execution thus fulfilling esthetic, occlusal, and functional parameters maintaining the harmony of the stomatognathic system. Crown lengthening procedures have become an integral component of the esthetic armamentarium and are utilized with increasing frequency to enhance the appearance of restorations placed in the esthetic zone. Crown lengthening plays a role to create healthy relationship of the gingiva and bone levels so as to gain access to more of the tooth which can be restored, if it is badly worn, decayed or fractured, below the gum line. This paper highlights the full mouth crown lengthening procedure performed on a patient with amelogenesis imperfecta.

  8. Amelogenesis Imperfecta, Facial Esthetics and Snap-On Smile.

    Science.gov (United States)

    Wilson, Lee; Bradshaw, Jonathan P; Marks, Murray K

    2015-01-01

    Amelogenesis imperfecta is a hereditary enamel protein disorder affecting deciduous and secondary crown formation. The prevalence ranges from 1:700 to 1:14,000 depending on the population. These teeth may be hypoplastic, hypomineralized, or hypermineralized and are often discolored, sensitive and caries vulnerable. Patients often present with psychosocial issues due to appearance. Primary teeth are often treated with stainless steel crowns while secondary teeth are treated with full coverage esthetic crowns. The presenting preteen male here was fitted with Snap-On Smile? (www.snaponsmile.com). This treatment option provided cosmetic enhancement of the patient's appearance besides stabilization without altering the primary and secondary dentition during adolescent development.

  9. Amelogenesis imperfecta - lifelong management. Restorative management of the adult patient.

    Science.gov (United States)

    Patel, M; McDonnell, S T; Iram, S; Chan, M F W-Y

    2013-11-08

    The biggest challenge restorative dentists face in rehabilitating patients with amelogenesis imperfecta (AI) is trying to restore aesthetics, function and occlusal stability while keeping the treatment as conservative as possible. The goals of treatment should be to prolong the life of the patient's own teeth and avoid or delay the need for extractions and subsequent replacement with conventional fixed, removable or implant retained prostheses. In order to achieve these goals a stepwise approach to treatment planning is required starting with the most conservative but aesthetically acceptable treatment. This article discusses the management of AI and presents the various treatment options available for restoring the adult patient who presents to the dentist with AI.

  10. Immediate Desensitization in Teeth Affected by Amelogenesis Imperfecta.

    Science.gov (United States)

    Moreira, Rudá França; Figueiredo, Rossana Gomes; Oliveira, Henrique Eduardo; Fonseca, Ana Christina Lamosa da; Miranda, Mauro Sayão de

    2016-01-01

    The aim of this paper was to describe a clinical case of immediate dental desensitization using a self-etch adhesive system in an adolescent patient diagnosed with amelogenesis imperfecta (AI). AI was associated with severe tooth sensitivity, treated by the application of a universal adhesive system for desensitization of the teeth affected by AI. Reduction of tooth sensitivity was assessed using a visual analog scale during all reevaluations. The technique was effective for reducing tooth sensitivity. It was concluded that the adhesive system for tooth desensitization had an immediate effect and maintained its effectiveness during a 12-month follow-up period.

  11. Conservative treatment for amelogenesis imperfecta: a case report.

    Science.gov (United States)

    Campos, Roberto Elias; Miranda Valdivia, Andrea Dolores Correia; Santos-Filho, Paulo Cesar de Freitas; Menezes, Murilo de Souza; de Oliveira Junior, Osmir Batista; Soares, Carlos Jose

    2014-01-01

    Amelogenesis imperfecta is a hereditary condition that can alter the thickness, color, and shape of tooth enamel. Recent adhesive materials and techniques have provided less invasive treatment options. This case report presents the treatment of a patient whose anterior teeth had color alterations, white spots, pits, and shape defects. Using a more conservative technique, the mandibular and maxillary anterior teeth were restored using veneer direct composite restorations. After 6 years, the restorations demonstrated no deterioration, and no pathology was seen in association with the rehabilitation.

  12. Amelogenesis Imperfecta: 1 Family, 2 Phenotypes, and 2 Mutated Genes.

    Science.gov (United States)

    Prasad, M K; Laouina, S; El Alloussi, M; Dollfus, H; Bloch-Zupan, A

    2016-12-01

    Amelogenesis imperfecta (AI) is a clinically and genetically heterogeneous group of diseases characterized by enamel defects. The authors have identified a large consanguineous Moroccan family segregating different clinical subtypes of hypoplastic and hypomineralized AI in different individuals within the family. Using targeted next-generation sequencing, the authors identified a novel heterozygous nonsense mutation in COL17A1 (c.1873C>T, p.R625*) segregating with hypoplastic AI and a novel homozygous 8-bp deletion in C4orf26 (c.39_46del, p.Cys14Glyfs*18) segregating with hypomineralized-hypoplastic AI in this family. This study highlights the phenotypic and genotypic heterogeneity of AI that can exist even within a single consanguineous family. Furthermore, the identification of novel mutations in COL17A1 and C4orf26 and their correlation with distinct AI phenotypes can contribute to a better understanding of the pathophysiology of AI and the contribution of these genes to amelogenesis.

  13. Dentin sialoprotein and dentin phosphoprotein overexpression during amelogenesis.

    Science.gov (United States)

    Paine, Michael L; Luo, Wen; Wang, Hong-Jun; Bringas, Pablo; Ngan, Amanda Y W; Miklus, Vetea G; Zhu, Dan-Hong; MacDougall, Mary; White, Shane N; Snead, Malcolm L

    2005-09-09

    The gene for dentin sialophosphoprotein produces a single protein that is post-translationally modified to generate two distinct extracellular proteins: dentin sialoprotein and dentin phosphoprotein. In teeth, dentin sialophosphoprotein is expressed primarily by odontoblast cells, but is also transiently expressed by presecretory ameloblasts. Because of this expression profile it appears that dentin sialophosphoprotein contributes to the early events of amelogenesis, and in particular to those events that result in the formation of the dentino-enamel junction and the adjacent "aprismatic" enamel. Using a transgenic animal approach we have extended dentin sialoprotein or dentin phosphoprotein expression throughout the developmental stages of amelogenesis. Overexpression of dentin sialoprotein results in an increased rate of enamel mineralization, however, the enamel morphology is not significantly altered. In wild-type animals, the inclusion of dentin sialoprotein in the forming aprismatic enamel may account for its increased hardness properties, when compared with bulk enamel. In contrast, the overexpression of dentin phosphoprotein creates "pitted" and "chalky" enamel of non-uniform thickness that is more prone to wear. Disruptions to the prismatic enamel structure are also a characteristic of the dentin phosphoprotein overexpressing animals. These data support the previous suggestion that dentin sialoprotein and dentin phosphoprotein have distinct functions related to tooth formation, and that the dentino-enamel junction should be viewed as a unique transition zone between enamel and the underlying dentin. These results support the notion that the dentin proteins expressed by presecretory ameloblasts contribute to the unique properties of the dentino-enamel junction.

  14. Occurrence of epidermolysis bullosa along with Amelogenesis imperfecta in female patient of India

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    A P Javed

    2013-01-01

    Full Text Available Epidermolysis bullosa (EB is an inherited disorder, which is characteristically presented as skin blisters developing in response to minor injury. Junctional variety of EB is also associated with enamel hypoplasia. Amelogenesis imperfecta presents with abnormal formation of the enamel both in deciduous and permanent dentition. This article describes a previously unreported case of Amelogenesis imperfecta with complete loss of enamel in a young female patient with EB.

  15. Occurrence of epidermolysis bullosa along with Amelogenesis imperfecta in female patient of India.

    Science.gov (United States)

    Javed, A P; Shenai, Prashanth; Chatra, Laxmikanth; Veena, K M; Rao, Prasanna Kumar; Prabhu, Rachana

    2013-11-01

    Epidermolysis bullosa (EB) is an inherited disorder, which is characteristically presented as skin blisters developing in response to minor injury. Junctional variety of EB is also associated with enamel hypoplasia. Amelogenesis imperfecta presents with abnormal formation of the enamel both in deciduous and permanent dentition. This article describes a previously unreported case of Amelogenesis imperfecta with complete loss of enamel in a young female patient with EB.

  16. Dental rehabilitation of amelogenesis imperfecta using thermoformed templates.

    Science.gov (United States)

    Sockalingam, Snmp

    2011-01-01

    Amelogenesis imperfecta represents a group of dental developmental conditions that are genomic in origin. Hypoplastic AI, hypomineralised AI or both in combination were the most common types seen clinically. This paper describes oral rehabilitation of a 9-year-old Malay girl with inherited hypoplastic AI using transparent thermoforming templates. The defective surface areas were reconstructed to their original dimensions on stone cast models of the upper and lower arches using composite, and transparent thermoform templates were fabricated on the models. The templates were used as crown formers to reconstruct the defective teeth clinically using esthetically matching composite. The usage of the templates allowed direct light curing of the composite, accurate reproducibility of the anatomic contours of the defective teeth, reduced chair-side time and easy contouring and placement of homogenous thickness of composite in otherwise inaccessible sites of the affected teeth.

  17. Bilateral nephrocalcinosis and amelogenesis imperfecta: A case report

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    Alok Patel

    2015-01-01

    Full Text Available Amelogenesis imperfecta (AI is a group of hereditary disorders that affect the quality and/or quantity of dental enamel. This paper describes the clinicopathological features of a patient who was born of nonconsanguineous parents and who presented with oral alterations, including yellow and misshapen teeth, intrapulpal calcifications, delayed tooth eruption, and gum enlargement. Scanning electron microscopy of the teeth revealed hypoplastic enamel, and a renal ultrasound detected bilateral nephrocalcinosis, leading to a diagnosis of AI and nephrocalcinosis syndrome. Since nephrocalcinosis is often asymptomatic and can be associated with impaired renal function, dentists who see children with a generalized and thin hypoplastic AI should consider a renal ultrasound scan and referral to a Nephrologist. Children with nephrocalcinosis should also be considered for a dental check.

  18. Structure of initial crystals formed during human amelogenesis

    Science.gov (United States)

    Cuisinier, F. J. G.; Voegel, J. C.; Yacaman, J.; Frank, R. M.

    1992-02-01

    X-ray diffraction analysis revealed only the existence of carbonated hydroxyapatite (c.HA) during amelogenesis, whereas conventional transmission electron microscopy investigations showed that developing enamel crystals have a ribbon-like habit. The described compositional changes could be an indication for the presence of minerals different from c.HA. However, the absence of identification of such a mineral shows the need of studies by high resolution electron microscopy (HREM) of initial formed human enamel crystals. We demonstrate the existence of two crystal families involved in the early stages of biomineralization: (a) nanometer-size particles which appeared as a precursor phase; (b) ribbon-like crystals, with a structure closely related to c.HA, which by a progressive thickening process tend to attain the mature enamel crystal habit.

  19. Amelogenesis Imperfecta and Screening of Mutation in Amelogenin Gene

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    Fernanda Veronese Oliveira

    2014-01-01

    Full Text Available The aim of this study was to report the clinical findings and the screening of mutations of amelogenin gene of a 7-year-old boy with amelogenesis imperfecta (AI. The genomic DNA was extracted from saliva of patient and his family, followed by PCR and direct DNA sequencing. The c.261C>T mutation was found in samples of mother, father, and brother, but the mutation was not found in the sequence of the patient. This mutation is a silent mutation and a single-nucleotide polymorphism (rs2106416. Thus, it is suggested that the mutation found was not related to the clinical presence of AI. Further research is necessary to examine larger number of patients and genes related to AI.

  20. Dental rehabilitation of amelogenesis imperfecta using thermoformed templates

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    SNMP Sockalingam

    2011-01-01

    Full Text Available Amelogenesis imperfecta represents a group of dental developmental conditions that are genomic in origin. Hypoplastic AI, hypomineralised AI or both in combination were the most common types seen clinically. This paper describes oral rehabilitation of a 9-year-old Malay girl with inherited hypoplastic AI using transparent thermoforming templates. The defective surface areas were reconstructed to their original dimensions on stone cast models of the upper and lower arches using composite, and transparent thermoform templates were fabricated on the models. The templates were used as crown formers to reconstruct the defective teeth clinically using esthetically matching composite. The usage of the templates allowed direct light curing of the composite, accurate reproducibility of the anatomic contours of the defective teeth, reduced chair-side time and easy contouring and placement of homogenous thickness of composite in otherwise inaccessible sites of the affected teeth.

  1. Amelogenesis imperfecta: A challenge to restoring esthetics and function

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    Ranganath V

    2010-01-01

    Full Text Available Rehabilitation of complicated cases poses difficulty in clinical practice, both with respect to restoring function and with esthetics. One such clinical condition where the dentist has to give importance to proper planning of the treatment and execution of the plan is amelogenesis imperfecta (AI, a condition where both function and esthetics are accommodated. This article discusses both the functional and esthetic rehabilitation of a patient with AI. Both the esthetics and function were hampered in this patient due to the condition. As a result, the treatment was properly planned and executed. A number of treatment options are available for us today to treat such a case. There is no one technique to be followed as such. However, the aim was to properly diagnose the case and provide good function and esthetics to the patient.

  2. Functional and esthetic rehabilitation of a patient with amelogenesis imperfecta.

    Science.gov (United States)

    Ergun, Gulfem; Kaya, Bekir Murat; Egilmez, Ferhan; Cekic-Nagas, Isil

    2013-01-01

    Amelogenesis imperfecta (AI) is a hereditary disorder that causes developmental alterations in the structure of enamel. In addition, tooth sensitivity, missing or impacted teeth, taurodontism, altered dental esthetics and anterior open bite can also be associated with AI. This clinical report presents the diagnosis, treatment planning and prosthetic rehabilitation of a 19-year-old female patient with AI associated with a group of dental anomalies. Following clinical and radiographic examination, histologic evaluation of the teeth confirmed the diagnosis of rough pattern hypoplastic AI. The patient was rehabilitated with full-mouth zirconium oxide ceramic fixed bridges. Adaptation of the temporomandibular joints and masticatory muscles to the bridges was carefully observed over 3 years. At the end of this follow-up period, the patient was satisfied with the esthetics, function and phonation of her prostheses.

  3. Bilateral nephrocalcinosis and amelogenesis imperfecta: A case report.

    Science.gov (United States)

    Patel, Alok; Jagtap, Chetana; Bhat, Chetan; Shah, Rohan

    2015-01-01

    Amelogenesis imperfecta (AI) is a group of hereditary disorders that affect the quality and/or quantity of dental enamel. This paper describes the clinicopathological features of a patient who was born of nonconsanguineous parents and who presented with oral alterations, including yellow and misshapen teeth, intrapulpal calcifications, delayed tooth eruption, and gum enlargement. Scanning electron microscopy of the teeth revealed hypoplastic enamel, and a renal ultrasound detected bilateral nephrocalcinosis, leading to a diagnosis of AI and nephrocalcinosis syndrome. Since nephrocalcinosis is often asymptomatic and can be associated with impaired renal function, dentists who see children with a generalized and thin hypoplastic AI should consider a renal ultrasound scan and referral to a Nephrologist. Children with nephrocalcinosis should also be considered for a dental check.

  4. Epileptic encephalopathy and amelogenesis imperfecta: Kohlschütter-Tönz syndrome.

    Science.gov (United States)

    Schossig, Anna; Wolf, Nicole I; Kapferer, Ines; Kohlschütter, Alfried; Zschocke, Johannes

    2012-05-01

    Kohlschütter-Tönz syndrome is a rare genetic disorder with epilepsy, psychomotor regression, and a severe enamel defect with yellow or brownish discoloration of the teeth. The first affected family was described in 1974, and 25 patients in 11 families have been reported until now. Inheritance is autosomal recessive. Epilepsy usually starts within the first or second year of life. All affected individuals show a psychomotor regression after onset of epilepsy or a developmental delay from birth on. Clinical course and disease severity are variable even within families. There are no known biochemical or other diagnostic markers of the condition. Very recently it has been shown that the condition is caused by mutations in the gene ROGDI but molecular data have only been reported for three families. It remains to be seen whether Kohlschütter-Tönz syndrome has the same molecular basis in all affected individuals.

  5. Possible Linkage of SP6 Transcriptional Activity with Amelogenesis by Protein Stabilization

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    Trianna W. Utami

    2011-01-01

    Full Text Available Ameloblasts produce enamel matrix proteins such as amelogenin, ameloblastin, and amelotin during tooth development. The molecular mechanisms of ameloblast differentiation (amelogenesis are currently not well understood. SP6 is a transcription factor of the Sp/KLF family that was recently found to regulate cell proliferation in a cell-type-specific manner. Sp6-deficient mice demonstrate characteristic tooth anomalies such as delayed eruption of the incisors and supernumerary teeth with disorganized amelogenesis. However, it remains unclear how Sp6 controls amelogenesis. In this study, we used SP6 high producer cells to identify SP6 target genes. Based on the observations that long-term culture of SP6 high producer cells reduced SP6 protein expression but not Sp6 mRNA expression, we found that SP6 is short lived and specifically degraded through a proteasome pathway. We established an in vitro inducible SP6 expression system coupled with siRNA knockdown and found a possible linkage between SP6 and amelogenesis through the regulation of amelotin and Rock1 gene expression by microarray analysis. Our findings suggest that the regulation of SP6 protein stability is one of the crucial steps in amelogenesis.

  6. Possible linkage of SP6 transcriptional activity with amelogenesis by protein stabilization.

    Science.gov (United States)

    Utami, Trianna W; Miyoshi, Keiko; Hagita, Hiroko; Yanuaryska, Ryna Dwi; Horiguchi, Taigo; Noma, Takafumi

    2011-01-01

    Ameloblasts produce enamel matrix proteins such as amelogenin, ameloblastin, and amelotin during tooth development. The molecular mechanisms of ameloblast differentiation (amelogenesis) are currently not well understood. SP6 is a transcription factor of the Sp/KLF family that was recently found to regulate cell proliferation in a cell-type-specific manner. Sp6-deficient mice demonstrate characteristic tooth anomalies such as delayed eruption of the incisors and supernumerary teeth with disorganized amelogenesis. However, it remains unclear how Sp6 controls amelogenesis. In this study, we used SP6 high producer cells to identify SP6 target genes. Based on the observations that long-term culture of SP6 high producer cells reduced SP6 protein expression but not Sp6 mRNA expression, we found that SP6 is short lived and specifically degraded through a proteasome pathway. We established an in vitro inducible SP6 expression system coupled with siRNA knockdown and found a possible linkage between SP6 and amelogenesis through the regulation of amelotin and Rock1 gene expression by microarray analysis. Our findings suggest that the regulation of SP6 protein stability is one of the crucial steps in amelogenesis.

  7. Enamel renal syndrome with associated amelogenesis imperfecta, nephrolithiasis, and hypocitraturia: A case report

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    Bhesania, Dhvani; Arora, Ankit; Kapoor, Sonali [Dept. of Conservative Dentistry and Endodontics, Manubhai Patel Dental College, Maharaja Krishnakumarsinhji Bhavnagar University, Vadodara (India)

    2015-09-15

    Numerous cases of enamel renal syndrome have been previously reported. Various terms, such as enamel renal syndrome, amelogenesis imperfecta and gingival fibromatosis syndrome, and enamel-renal-gingival syndrome, have been used for patients presenting with the dental phenotype characteristic of this condition, nephrocalcinosis or nephrolithiasis, and gingival findings. This report describes a case of amelogenesis imperfecta of the enamel agenesis variety with nephrolithiasis in a 21-year-old male patient who complained of small teeth. The imaging modalities employed were conventional radiography, cone-beam computed tomography, and renal sonography. Such cases are first encountered by dentists, as other organ or metabolic diseases are generally hidden. Hence, cases of amelogenesis imperfecta should be subjected to advanced diagnostic modalities, incorporating both dental and medical criteria, in order to facilitate comprehensive long-term management.

  8. Dental management of amelogenesis imperfecta patients: a primer on genotype-phenotype correlations.

    Science.gov (United States)

    Ng, F K; Messer, L B

    2009-01-01

    Amelogenesis imperfecta (AI) represents a group of hereditary conditions which affects enamel formation in the primary and permanent dentitions. Mutations in genes critical for amelogenesis result in diverse phenotypes characterized by variably thin and/or defective enamel. To date, mutations in 5 genes are known to cause AI in humans. Understanding the molecular etiologies and associated inheritance patterns can assist in the early diagnosis of this condition. Recognition of genotype-phenotype correlations will allow clinicians to guide genetic testing and select appropriate management strategies for patients who express different phenotypes. The purpose of this paper was to provide a narrative review of the current literature on amelogenesis imperfecta, particularly regarding recent advances in the identification of candidate genes and the patterns of inheritance.

  9. Amelogenesis Imperfecta with Taurodontism, Microdontia, and Minor Thalassemia: A Case Report

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    Fatemeh Mazhari

    2013-12-01

    Full Text Available Amelogenesis imperfecta is a group of genetic disorders that affects both the morphology and quality of tooth structure. Although the disease entity is primarily associated with abnormalities of dental and oral structures, it has been reported to be associated with a few syndromes. A 9-year-old girl with minor thalassemia referred to the Department of Pediatric Dentistry of the Mashhad Faculty of Dentistry with a complaint of sensitivity of first permanent molars. Dental findings consisted of amelogenesis imperfecta, microdontia, posterior cross bite and taurodontism. This is the first report of thalassemia accompanied with amelogenesis imperfecta. Although the patients often are non-symptomatic, the trait can be passed on to a child and if both parents carry the trait, the child could develop a more severe form of the disease; therefore, early diagnosis is important.

  10. Enamel renal syndrome with associated amelogenesis imperfecta, nephrolithiasis, and hypocitraturia: A case report.

    Science.gov (United States)

    Bhesania, Dhvani; Arora, Ankit; Kapoor, Sonali

    2015-09-01

    Numerous cases of enamel renal syndrome have been previously reported. Various terms, such as enamel renal syndrome, amelogenesis imperfecta and gingival fibromatosis syndrome, and enamel-renal-gingival syndrome, have been used for patients presenting with the dental phenotype characteristic of this condition, nephrocalcinosis or nephrolithiasis, and gingival findings. This report describes a case of amelogenesis imperfecta of the enamel agenesis variety with nephrolithiasis in a 21-year-old male patient who complained of small teeth. The imaging modalities employed were conventional radiography, cone-beam computed tomography, and renal sonography. Such cases are first encountered by dentists, as other organ or metabolic diseases are generally hidden. Hence, cases of amelogenesis imperfecta should be subjected to advanced diagnostic modalities, incorporating both dental and medical criteria, in order to facilitate comprehensive long-term management.

  11. Esthetic and functional rehabilitation of mutilated dentition and loss of vertical dimension due to amelogenesis imperfecta.

    Science.gov (United States)

    Mittal, Shweta; Tewari, Sanjay; Goel, Rajat

    2014-04-01

    Cases of severe attrition are a common finding. Among the congenital anomalies, amelogenesis imperfecta and dentinogenesis imperfecta are important conditions that may cause accelerated wear of teeth. The following case report describes the complete oral rehabilitation of a patient diagnosed with amelogenesis imperfecta. A detailed treatment plan was chalked out which included proper oral hygiene measures, restoration of carious teeth and endodontic treatment followed by foundation restorations of teeth that were crucial for the final prostheses. Patient was given transitional restorations for about 6 weeks with the aim of regaining the lost vertical dimensions. Final rehabilitation was done by fixed dental prostheses.

  12. Diagnosis and esthetic functional rehabilitation of a patient with amelogenesis imperfecta.

    Science.gov (United States)

    Oliveira, Ilione Kruschewsky Costa Sousa; Fonseca, Jussara de Fatima Barbosa; do Amaral, Flavia Lucisano Botelho; Pecorari, Vanessa Gallego Arias; Basting, Roberta Tarkany; França, Fabiana Mantovani Gomes

    2011-06-01

    Amelogenesis imperfecta is a hereditary disease that causes structural anomalies in dental enamel of both the primary and permanent dentition. The anomaly may present a variety of clinical forms and appearances, with its main characteristics being the loss of tooth structure, compromised esthetic appearance, and dental sensitivity. The aim of this study was to present the clinical report of a 16-year-old patient with severely compromised esthetics as a result of amelogenesis imperfecta of the hypocalcified type who was rehabilitated with composite resin and ceramic crowns.

  13. No Evidence for Association between Amelogenesis Imperfecta and Candidate Genes

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    M Ghandehari Motlagh

    2009-03-01

    Full Text Available "nBackground: Amelogenesis imperfecta (AI is an inherited tooth disorder. Despite the fact that up to now, several gene muta­tions in MMP20, ENAM, AMELX and KLK4 genes have been reported to be associated with AI, many other genes sug­gested to be involved. The main objective of this study was to find the mutations in three major candidate genes including MMP20, ENAM and KLK4 responsible for AI from three Iranian families with generalized hypoplastic phenotype in all teeth. "nMethods: All exon/intron boundaries of subjected genes were amplified by polymerase chain reaction and subjected to direct sequencing."nResults: One polymorphisms was identified in KLK4 exon 2, in one family a homozygous mutation was found in the third base of codon 22 for serine (TCG>TCT, but not in other families. Although these base substitutions have been occurred in the signaling domain, they do not seem to influence the activity of KLK4 protein."nConclusion: Our results might support the further evidence for genetic heterogeneity; at least, in some AI cases are not caused by a gene in these reported candidate genes.

  14. Minimally invasive rehabilitation of a patient with amelogenesis imperfecta.

    Science.gov (United States)

    Büchi, Dominik; Fehmer, Vincent; Sailer, Irene; Wolleb, Karin; Jung, Ronald

    2014-01-01

    This case report describes a minimally invasive step-by-step approach to treat a patient with amelogenesis imperfecta. This is a genetic developmental disorder of the dental enamel, which clinically manifests as white and dark discolorations of the teeth. The clinical examination did not reveal the true depth of the staining. Therefore, a step-wise treatment approach was chosen. The first step consisted of a home bleaching procedure, which led to a slight improvement of the esthetic appearance, but the stains were still clearly visible. The next step was the application of a microabrasion technique. This led to further improvement, but not to a satisfactory result for this patient who had high esthetic expectations. Thus, the third step was undertaken: it was planned to restore the maxillary incisors and canines with ceramic veneers. The dental technician prepared a wax-up, which served as a basis for a clinical mock-up. After discussing the mock-up and the treatment plan with the patient, crown lengthening was performed on teeth 11 and 23 to improve the pink esthetics. Subsequently, the teeth were prepared in a minimally invasive way and a final impression was taken. Following try-in, the six veneers were inserted with resin cement.

  15. The specific role of FAM20C in amelogenesis.

    Science.gov (United States)

    Wang, X; Jung, J; Liu, Y; Yuan, B; Lu, Y; Feng, J Q; Qin, C

    2013-11-01

    Previously, we showed that Sox2-Cre;Fam20C(fl/fl) mice in which Fam20C was ubiquitously inactivated had severe defects in dentin, enamel, and bone, along with hypophosphatemia. It remains to be determined if the enamel defects in the mice with universal inactivation of Family with sequence similarity 20-C (FAM20C) were associated with the dentin defects and whether hypophosphatemia in the knockout mice contributed to the enamel defects. In this study, we crossed Fam20C(fl/fl) mice with keratin 14-Cre (K14-Cre) transgenic mice to specifically inactivate Fam20C in the epithelial cells, including the dental epithelial cells that are responsible for forming tooth enamel. X-ray, backscattered scanning electron microscopic, and histological analyses showed that the K14-Cre;Fam20C(fl/fl) mice had severe enamel and ameloblast defects, while their dentin and alveolar bone were not significantly affected. Accordingly, serum biochemistry of the K14-Cre;Fam20C(fl/fl) mice showed normal phosphate and FGF23 levels in the circulation. Analysis of these data indicates that, while FAM20C is a molecule essential to amelogenesis, its inactivation in the dental epithelium does not significantly affect dentinogenesis. Hypophosphatemia makes no significant contribution to the enamel defects in the mice with the ubiquitous deletion of Fam20C.

  16. Adenovirus gene transfer to amelogenesis imperfecta ameloblast-like cells.

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    Anton V Borovjagin

    Full Text Available To explore gene therapy strategies for amelogenesis imperfecta (AI, a human ameloblast-like cell population was established from third molars of an AI-affected patient. These cells were characterized by expression of cytokeratin 14, major enamel proteins and alkaline phosphatase staining. Suboptimal transduction of the ameloblast-like cells by an adenovirus type 5 (Ad5 vector was consistent with lower levels of the coxsackie-and-adenovirus receptor (CAR on those cells relative to CAR-positive A549 cells. To overcome CAR -deficiency, we evaluated capsid-modified Ad5 vectors with various genetic capsid modifications including "pK7" and/or "RGD" motif-containing short peptides incorporated in the capsid protein fiber as well as fiber chimera with the Ad serotype 3 (Ad3 fiber "knob" domain. All fiber modifications provided an augmented transduction of AI-ameloblasts, revealed following vector dose normalization in A549 cells with a superior effect (up to 404-fold of pK7/RGD double modification. This robust infectivity enhancement occurred through vector binding to both α(vβ3/α(vβ5 integrins and heparan sulfate proteoglycans (HSPGs highly expressed by AI-ameloblasts as revealed by gene transfer blocking experiments. This work thus not only pioneers establishment of human AI ameloblast-like cell population as a model for in vitro studies but also reveals an optimal infectivity-enhancement strategy for a potential Ad5 vector-mediated gene therapy for AI.

  17. Transcriptional factor DLX3 promotes the gene expression of enamel matrix proteins during amelogenesis.

    Science.gov (United States)

    Zhang, Zhichun; Tian, Hua; Lv, Ping; Wang, Weiping; Jia, Zhuqing; Wang, Sainan; Zhou, Chunyan; Gao, Xuejun

    2015-01-01

    Mutation of distal-less homeobox 3 (DLX3) is responsible for human tricho-dento-osseous syndrome (TDO) with amelogenesis imperfecta, indicating a crucial role of DLX3 in amelogenesis. However, the expression pattern of DLX3 and its specific function in amelogenesis remain largely unknown. The aim of this study was to investigate the effects of DLX3 on enamel matrix protein (EMP) genes. By immunohistochemistry assays of mouse tooth germs, stronger immunostaining of DLX3 protein was identified in ameloblasts in the secretory stage than in the pre-secretory and maturation stages, and the same pattern was found for Dlx3 mRNA using Realtime PCR. In a mouse ameloblast cell lineage, forced expression of DLX3 up-regulated the expression of the EMP genes Amelx, Enam, Klk4, and Odam, whereas knockdown of DLX3 down-regulated these four EMP genes. Further, bioinformatics, chromatin immunoprecipitation, and luciferase assays revealed that DLX3 transactivated Enam, Amelx, and Odam through direct binding to their enhancer regions. Particularly, over-expression of mutant-DLX3 (c.571_574delGGGG, responsible for TDO) inhibited the activation function of DLX3 on expression levels and promoter activities of the Enam, Amelx, and Odam genes. Together, our data show that DLX3 promotes the expression of the EMP genes Amelx, Enam, Klk4, and Odam in amelogenesis, while mutant-DLX3 disrupts this regulatory function, thus providing insights into the molecular mechanisms underlying the enamel defects of TDO disease.

  18. Prosthetic and Surgical Approach for Oral Rehabilitation in a Patient with Amelogenesis Imperfecta: A Clinical Report

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    H. Sazegara

    2007-06-01

    Full Text Available Amelogenesis imperfecta is a heterogeneous group of hereditary disorders. Its treatment continues throughout the patients’ childhood and adolescence and consists of advanced restorative care in severe cases.A thorough prosthodontic treatment plan including orthognatic surgery, full veneer crowns and all ceramic anterior crowns is presented in this clinical report.

  19. Ceramic Veneers and Direct-Composite Cases of Amelogenesis Imperfecta Rehabilitation.

    Science.gov (United States)

    Shibata, S; Taguchi, Cmc; Gondo, R; Stolf, S C; Baratieri, L N

    2016-01-01

    The aim of this article is to present two case reports for the treatment of patients affected with amelogenesis imperfecta. One case was treated with composite resin and the other case with ceramic veneers. Esthetic and functional results were achieved using both treatments, and a review of advantages and disadvantages is presented.

  20. Comparative temporospatial expression profiling of murine amelotin protein during amelogenesis.

    Science.gov (United States)

    Somogyi-Ganss, Eszter; Nakayama, Yohei; Iwasaki, Kengo; Nakano, Yukiko; Stolf, Daiana; McKee, Marc D; Ganss, Bernhard

    2012-01-01

    Tooth enamel is formed in a typical biomineralization process under the guidance of specific organic components. Amelotin (AMTN) is a recently identified, secreted protein that is transcribed predominantly during the maturation stage of enamel formation, but its protein expression profile throughout amelogenesis has not been described in detail. The main objective of this study was to define the spatiotemporal expression profile of AMTN during tooth development in comparison with other known enamel proteins. A peptide antibody against AMTN was raised in rabbits, affinity purified and used for immunohistochemical analyses on sagittal and transverse paraffin sections of decalcified mouse hemimandibles. The localization of AMTN was compared to that of known enamel proteins amelogenin, ameloblastin, enamelin, odontogenic ameloblast-associated/amyloid in Pindborg tumors and kallikrein 4. Three-dimensional images of AMTN localization in molars at selected ages were reconstructed from serial stained sections, and transmission electron microscopy was used for ultrastructural localization of AMTN. AMTN was detected in ameloblasts of molars in a transient fashion, declining at the time of tooth eruption. Prominent expression in maturation stage ameloblasts of the continuously erupting incisor persisted into adulthood. In contrast, amelogenin, ameloblastin and enamelin were predominantly found during the early secretory stage, while odontogenic ameloblast-associated/amyloid in Pindborg tumors and kallikrein 4 expression in maturation stage ameloblasts paralleled that of AMTN. Secreted AMTN was detected at the interface between ameloblasts and the mineralized enamel. Recombinant AMTN protein did not mediate cell attachment in vitro. These results suggest a primary role for AMTN in the late stages of enamel mineralization.

  1. Retinoic Acid Excess Impairs Amelogenesis Inducing Enamel Defects

    Science.gov (United States)

    Morkmued, Supawich; Laugel-Haushalter, Virginie; Mathieu, Eric; Schuhbaur, Brigitte; Hemmerlé, Joseph; Dollé, Pascal; Bloch-Zupan, Agnès; Niederreither, Karen

    2017-01-01

    Abnormalities of enamel matrix proteins deposition, mineralization, or degradation during tooth development are responsible for a spectrum of either genetic diseases termed Amelogenesis imperfecta or acquired enamel defects. To assess if environmental/nutritional factors can exacerbate enamel defects, we investigated the role of the active form of vitamin A, retinoic acid (RA). Robust expression of RA-degrading enzymes Cyp26b1 and Cyp26c1 in developing murine teeth suggested RA excess would reduce tooth hard tissue mineralization, adversely affecting enamel. We employed a protocol where RA was supplied to pregnant mice as a food supplement, at a concentration estimated to result in moderate elevations in serum RA levels. This supplementation led to severe enamel defects in adult mice born from pregnant dams, with most severe alterations observed for treatments from embryonic day (E)12.5 to E16.5. We identified the enamel matrix proteins enamelin (Enam), ameloblastin (Ambn), and odontogenic ameloblast-associated protein (Odam) as target genes affected by excess RA, exhibiting mRNA reductions of over 20-fold in lower incisors at E16.5. RA treatments also affected bone formation, reducing mineralization. Accordingly, craniofacial ossification was drastically reduced after 2 days of treatment (E14.5). Massive RNA-sequencing (RNA-seq) was performed on E14.5 and E16.5 lower incisors. Reductions in Runx2 (a key transcriptional regulator of bone and enamel differentiation) and its targets were observed at E14.5 in RA-exposed embryos. RNA-seq analysis further indicated that bone growth factors, extracellular matrix, and calcium homeostasis were perturbed. Genes mutated in human AI (ENAM, AMBN, AMELX, AMTN, KLK4) were reduced in expression at E16.5. Our observations support a model in which elevated RA signaling at fetal stages affects dental cell lineages. Thereafter enamel protein production is impaired, leading to permanent enamel alterations. PMID:28111553

  2. GEP, a Local Growth Factor, is Critical for Odontogenesis and Amelogenesis

    Directory of Open Access Journals (Sweden)

    Zhengguo Cao, Baichun Jiang, Yixia Xie, Chuan-ju Liu, Jian Q. Feng

    2010-01-01

    Full Text Available Granulin epithelin precursor (GEP is a new growth factor that functions in brain development, chondrogenesis, tissue regeneration, tumorigenesis, and inflammation. The goal of this study was to study whether GEP was critical for odontogenesis and amelogenesis both in vivo and in vitro. The in situ hybridization and immunohistochemistry data showed that GEP was expressed in both odontoblast and ameloblast cells postnatally. Knockdown of GEP by crossing U6-ploxPneo-GEP and Sox2-Cre transgenic mice led to a reduction of dentin thickness, an increase in predentin thickness, and a reduction in mineral content in enamel. The in vitro application of recombinant GEP up-regulated molecular markers important for odontogenesis (DMP1, DSPP, and ALP and amelogenesis (ameloblastin, amelogenin and enamelin. In conclusion, both the in vivo and the in vivo data support an important role of GEP in tooth formation during postnatal development.

  3. GEP, a local growth factor, is critical for odontogenesis and amelogenesis.

    Science.gov (United States)

    Cao, Zhengguo; Jiang, Baichun; Xie, Yixia; Liu, Chuan-ju; Feng, Jian Q

    2010-11-25

    Granulin epithelin precursor (GEP) is a new growth factor that functions in brain development, chondrogenesis, tissue regeneration, tumorigenesis, and inflammation. The goal of this study was to study whether GEP was critical for odontogenesis and amelogenesis both in vivo and in vitro. The in situ hybridization and immunohistochemistry data showed that GEP was expressed in both odontoblast and ameloblast cells postnatally. Knockdown of GEP by crossing U6-ploxPneo-GEP and Sox2-Cre transgenic mice led to a reduction of dentin thickness, an increase in predentin thickness, and a reduction in mineral content in enamel. The in vitro application of recombinant GEP up-regulated molecular markers important for odontogenesis (DMP1, DSPP, and ALP) and amelogenesis (ameloblastin, amelogenin and enamelin). In conclusion, both the in vivo and the in vivo data support an important role of GEP in tooth formation during postnatal development.

  4. Scanning electron microscopy and calcification in amelogenesis imperfecta in anterior and posterior human teeth

    OpenAIRE

    Sánchez-Quevedo, M. C.; Ceballos, G.; García, J. M.; Rodriguez, I. A.; Gómez de Ferraris, M. E.; Campos, Antonio

    2001-01-01

    Teeth fragments from members of a famil? clinically and genetically diagnosed as having amelogenesis imperfecta were studied by scanning electron microscopy and X-ray microprobe analysis to establish the morphological patterns and the quantitative concentration of calcium in the enamel of anterior (canine, incisor) and posterior (premolar and molar) teeth. The prism patterns in the enamel of teeth from both regions were parallel or irregularly decussate, with ...

  5. Transcriptional factor DLX3 promotes the gene expression of enamel matrix proteins during amelogenesis.

    Directory of Open Access Journals (Sweden)

    Zhichun Zhang

    Full Text Available Mutation of distal-less homeobox 3 (DLX3 is responsible for human tricho-dento-osseous syndrome (TDO with amelogenesis imperfecta, indicating a crucial role of DLX3 in amelogenesis. However, the expression pattern of DLX3 and its specific function in amelogenesis remain largely unknown. The aim of this study was to investigate the effects of DLX3 on enamel matrix protein (EMP genes. By immunohistochemistry assays of mouse tooth germs, stronger immunostaining of DLX3 protein was identified in ameloblasts in the secretory stage than in the pre-secretory and maturation stages, and the same pattern was found for Dlx3 mRNA using Realtime PCR. In a mouse ameloblast cell lineage, forced expression of DLX3 up-regulated the expression of the EMP genes Amelx, Enam, Klk4, and Odam, whereas knockdown of DLX3 down-regulated these four EMP genes. Further, bioinformatics, chromatin immunoprecipitation, and luciferase assays revealed that DLX3 transactivated Enam, Amelx, and Odam through direct binding to their enhancer regions. Particularly, over-expression of mutant-DLX3 (c.571_574delGGGG, responsible for TDO inhibited the activation function of DLX3 on expression levels and promoter activities of the Enam, Amelx, and Odam genes. Together, our data show that DLX3 promotes the expression of the EMP genes Amelx, Enam, Klk4, and Odam in amelogenesis, while mutant-DLX3 disrupts this regulatory function, thus providing insights into the molecular mechanisms underlying the enamel defects of TDO disease.

  6. Aesthetic And Functional Rehabilitation Of The Primary Dentition Affected By Amelogenesis Imperfecta.

    OpenAIRE

    Maria Carolina Salomé Marquezin; Bruna Raquel Zancopé; Larissa Ferreira Pacheco; Maria Beatriz Duarte Gavião; Fernanda Miori Pascon

    2015-01-01

    The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI) in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars wit...

  7. "Dermatoglyphic Observations in an Iranian Girl Affected with Congenital Cutis Laxa (Autosomal Recessive"

    Directory of Open Access Journals (Sweden)

    H Pour-Jafari

    2003-08-01

    Full Text Available The aim of the this work was to determine the finger patterns, Finger Ridge Count (FRC, Total Finger Ridge Count (TFRC, and Asymmetry of Finger Ridge Count (AFRC of an Iranian girl (aged 13 years affected with congenital cutis laxa (CCL.The fingerprints of the first phalanx of both hands were taken by using the standard method (stamp ink. The fingerprints were classified according to the Galton nomenclature. The patterns of palm creases were also studied. Besides, the ridges of fingerprints of all ten fingers were counted, then employing the related formulas, the FRC, TFRC and AFRC were calculated.Results showed that the finger patterns of all ten fingers were radial loop; the major creases of the palms existed but their sizes were not normal. TFRC, which is the sum of all ten FRCs, was 77 (“low”, and AFRC was 10.344, more than that of her normal sister, that was 7.280. It is concluded that in CCL, the TFRC and symmetry of the fingertips ridges count may decrease; also palm pattern may be unusual.

  8. Mutations in c10orf11, a melanocyte-differentiation gene, cause autosomal-recessive albinism

    DEFF Research Database (Denmark)

    Grønskov, Karen; Dooley, Christopher M; Østergaard, Elsebet

    2013-01-01

    in an individual originating from Lithuania. Immunohistochemistry showed localization of C10orf11 in melanoblasts and melanocytes in human fetal tissue, but no localization was seen in retinal pigment epithelial cells. Knockdown of the zebrafish (Danio rerio) homolog with the use of morpholinos resulted...... in substantially decreased pigmentation and a reduction of the apparent number of pigmented melanocytes. The morphant phenotype was rescued by wild-type C10orf11, but not by mutant C10orf11. In conclusion, we have identified a melanocyte-differentiation gene, C10orf11, which when mutated causes autosomal...

  9. Missense variants in AIMP1 gene are implicated in autosomal recessive intellectual disability without neurodegeneration

    NARCIS (Netherlands)

    Iqbal, Z.; Puttmann, L.; Musante, L.; Razzaq, A.; Zahoor, M.Y.; Hu, H; Wienker, T.F.; Garshasbi, M.; Fattahi, Z.; Gilissen, C.; Vissers, L.E.; Brouwer, A.P. de; Veltman, J.A.; Pfundt, R.P.; Najmabadi, H.; Ropers, H.H.; Riazuddin, S.; Kahrizi, K.; Bokhoven, H. van

    2016-01-01

    AIMP1/p43 is a multifunctional non-catalytic component of the multisynthetase complex. The complex consists of nine catalytic and three non-catalytic proteins, which catalyze the ligation of amino acids to their cognate tRNA isoacceptors for use in protein translation. To date, two allelic variants

  10. Genetic dissection of two Pakistani families with consanguineous localized autosomal recessive hypotrichosis (LAH

    Directory of Open Access Journals (Sweden)

    Seyyedha Abbas

    2014-07-01

    Conclusion:Both families were tested for linkage by genotyping polymorphic microsatellite markers linked to known alopecia loci. Family A excluded all known diseased regions that is suggestive of some novel chromosomal disorder. However, sequencing of P2RY5 gene in family B showed no pathogenic mutation.

  11. Autosomal recessive agammaglobulinemia: novel insights from mutations in Ig-beta.

    Science.gov (United States)

    Lougaris, Vassilios; Ferrari, Simona; Cattalini, Marco; Soresina, Annarosa; Plebani, Alessandro

    2008-09-01

    Agammaglobulinemia is a rare primary immuno-deficiency characterized by an early block of B-cell development in the bone marrow resulting in the absence of peripheral B cells and low/absent immunoglobulin serum levels. Mutations in the Bruton tyrosine kinase and in components of the pre-B-cell receptor (pre-BCR), such as mu heavy chain, surrogate light chain, and Igalpha have been found in 85% to 90% of patients affected by this disease. Here we review the recent advances in the characterization of molecular defects underlying an early block in B-cell development, focusing on the novel finding of the first two patients with agammaglobulinemia caused by mutations in Igbeta, the transmembrane protein that associates with Igalpha as part of the pre-BCR complex. Characterization of novel genetic defects involving components of the pre-BCR is crucial for a better understanding of the biology of early B-cell development and may have therapeutic and prognostic implications.

  12. Vici Syndrome: A Rare Autosomal Recessive Syndrome with Brain Anomalies, Cardiomyopathy, and Severe Intellectual Disability

    Directory of Open Access Journals (Sweden)

    R. Curtis Rogers

    2011-01-01

    Full Text Available Purpose. The objective of this study was to present and describe two additional patients diagnosed with Vici syndrome. Methods. Clinical, laboratory, and imaging findings of the two siblings are discussed in detail. The two patients' descriptions are compared with the other eleven patients reported in the literature. We also presented detailed autopsy results on the male sibling, which demonstrated cytoplasmic vacuoles of the cardiomyocytes and confirmed the clinical findings. Results. The patients reported here include the 13th and 14th patients reported with Vici syndrome. The summary of findings present in these patients includes postnatal growth retardation, developmental delay, bilateral cataracts, agenesis of the corpus callosum, cerebellar anomalies, gyral abnormalities, seizures, hypotonia, and cardiomyopathy. Conclusion. Vici syndrome should be suspected in any child with agenesis of the corpus callosum and one of the following findings: cardiomyopathy, cataracts, immune deficiency, or cutaneous hypopigmentation.

  13. Decreased bone density and treatment in patients with autosomal recessive cutis laxa.

    NARCIS (Netherlands)

    Noordam, C.; Funke, S.; Slobbe-Knoers, V.V.A.M.; Jira, P.E.; Wevers, R.A.; Urban, Z.; Morava, E.

    2009-01-01

    AIM: Due to the occasional association pathological fractures and osteoporosis we evaluated four patients with cutis laxa syndrome for skeletal anomalies. PATIENT/METHODS: We prospectively evaluated four patients, a male and a female child and a brother-sister sib pair, with dysmorphic features, gro

  14. Spectrum of mutations in the renin-angiotensin system genes in autosomal recessive renal tubular dysgenesis

    DEFF Research Database (Denmark)

    Gribouval, Olivier; Morinière, Vincent; Pawtowski, Audrey

    2012-01-01

    , pulmonary hypoplasia, and refractory arterial hypotension. The disease is linked to mutations in the genes encoding several components of the renin-angiotensin system (RAS): AGT (angiotensinogen), REN (renin), ACE (angiotensin-converting enzyme), and AGTR1 (angiotensin II receptor type 1). Here, we review...

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

    NARCIS (Netherlands)

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

    2009-01-01

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

  16. An autosomal recessive cerebellar ataxia syndrome with upward gaze palsy, neuropathy, and seizures

    NARCIS (Netherlands)

    Straussberg, R; Basel-Vanagaite, L; Kivity, S; Dabby, R; Cirak, S; Nurnberg, P; Voit, T; Mahajnah, M; Inbar, D; Saifi, GM; Lupski, [No Value; Delague, [No Value; Megarbane, A; Richter, A; Leshinsky, E; Berkovic, SF

    2005-01-01

    The authors describe three siblings born to consanguineous parents with early onset ataxia, dysarthria, myoclonic, generalized tonic clonic seizures, upward gaze palsy, extensor plantar reflexes, sensory neuropathy, and normal cognition. Direct screening excluded mutations in FRDA, TDP1, and SACS ge

  17. Identification of the CRB1 gene and analysis of its role in autosomal recessive retinal dystrophies

    NARCIS (Netherlands)

    Hollander, Antonia Ingrid den

    2002-01-01

    Inherited retinal dystrophies generally lead to severe visual impairment early in life. Most genes involved in retinal dystrophies are expressed exclusively or predominantly in the retina or the RPE. To identify candidate genes for inherited retinal dystrophies, we isolated

  18. [Autosomal recessive GTPCH 1 deficiency: the importance of the analysis of neurotransmitters in cerebrospinal fluid].

    Science.gov (United States)

    Moreno-Medinilla, E E; Mora-Ramirez, M D; Calvo-Medina, R; Martinez-Anton, J

    2016-06-01

    Introduccion. El deficit de la enzima trifosfato de guanosina ciclohidrolasa 1 (GTPCH 1) origina una disminucion de la sintesis de la tetrahidrobiopterina (BH4), cofactor indispensable en la sintesis de la tirosina, la dopamina y la serotonina. Es una enfermedad poco frecuente que produce un retraso o regresion psicomotora y trastornos del movimiento, y en la que el tratamiento puede mejorar o incluso corregir la clinica. Caso clinico. Niña afecta de deficit de GTPCH con herencia autosomica recesiva, diagnosticada a los 14 meses con estudio del liquido cefalorraquideo con deficit de pterinas, HVA y 5-HIAA, test de sobrecarga de fenilalanina y estudio genetico positivos. La clinica comenzo a los 5 meses con temblor cefalico y de las extremidades superiores, en reposo e intencional, intermitente, que desaparecio en un mes. El desarrollo psicomotor era normal, destacaba una hipotonia axial leve en la exploracion y las pruebas complementarias realizadas fueron normales. Posteriormente presento regresion psicomotora con perdida del sosten cefalico, disminucion de los movimientos activos, dificultad para la manipulacion bimanual, hipomimia e hipotonia global grave, lo que motivo el estudio de una encefalopatia progresiva. Tras el diagnostico de deficit de GTPCH, inicio tratamiento sustitutivo con levodopa/carbidopa, OH triptofano y BH4, con muy buena evolucion tanto motora como cognitiva. Actualmente, la paciente tiene 5 años, presenta un desarrollo psicomotor adecuado a su edad, cursa tercer curso de educacion infantil y ha alcanzado el nivel de su clase. Conclusion. Hay que destacar en este caso la mejoria tan satisfactoria, tanto motora como cognitiva, tras iniciar el tratamiento sustitutivo, ya que el nivel cognitivo suele quedar afectado en muchos casos.

  19. A mutation in CABP2, expressed in cochlear hair cells, causes autosomal-recessive hearing impairment

    NARCIS (Netherlands)

    Schrauwen, I.; Helfmann, S.; Inagaki, A.; Predoehl, F.; Tabatabaiefar, M.A.; Picher, M.M.; Sommen, M.; Seco, C.Z.; Oostrik, J.; Kremer, J.M.J.; Dheedene, A.; Claes, C.; Fransen, E.; Chaleshtori, M.H.; Coucke, P.; Lee, A.; Moser, T.; Camp, G. van

    2012-01-01

    CaBPs are a family of Ca(2+)-binding proteins related to calmodulin and are localized in the brain and sensory organs, including the retina and cochlea. Although their physiological roles are not yet fully elucidated, CaBPs modulate Ca(2+) signaling through effectors such as voltage-gated Ca(v) Ca(2

  20. CLPB Variants Associated with Autosomal-Recessive Mitochondrial Disorder with Cataract, Neutropenia, Epilepsy, and Methylglutaconic Aciduria

    DEFF Research Database (Denmark)

    Saunders, Carol; Smith, Laurie; Wibrand, Flemming;

    2015-01-01

    of type IV 3-MGA-uria characterized by cataracts, severe psychomotor regression during febrile episodes, epilepsy, neutropenia with frequent infections, and death in early childhood. Four of the individuals were of Greenlandic descent, and one was North American, of Northern European and Asian descent......3-methylglutaconic aciduria (3-MGA-uria) is a nonspecific finding associated with mitochondrial dysfunction, including defects of oxidative phosphorylation. 3-MGA-uria is classified into five groups, of which one, type IV, is genetically heterogeneous. Here we report five children with a form...

  1. Screening for homozygosity by descent in families with autosomal recessive retinitis pigmentosa

    Indian Academy of Sciences (India)

    Kota Lalitha; Subhadra Jalali; Tejas Kadakia; Chitra Kannabiran

    2002-08-01

    Retinitis pigmentosa (RP) is a genetically heterogeneous disease and an important cause of blindness in the state of Andhra Pradesh in India. In an attempt to identify the disease locus in families with the recessive form of the disease, we used the approach of screening for homozygosity by descent in offspring of consanguineous and nonconsanguineous families with RP. Microsatellite markers closely flanking 21 known candidate genes for RP were genotyped in parents and affected offspring to determine whether there was homozygosity at these loci that was shared by affected individuals of a family. This screening approach may be a rapid preliminary method to test known loci for possible cosegregation with disease.

  2. Radiation effect on the stages of amelogenesis in the rat incisor

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Hyun Bae; Choi, Soon Chul; Park, Tae Won; You, Dong Soo [Dept. of Oral and Maxillofacial Radiology, College of Dentistry, Seoul National University, Seoul (Korea, Republic of)

    1997-02-15

    The purpose of this study was to investigate the radiation effect on the stages of amelogenesis. Twenty 11-day-old rats which were irradiated by 4 GY of gamma radiation on the 19th prenatal day were used for the experimental group and twenty 11-day-old rats which were not irradiated were used for the control group. The length of each zone of amelogenesis were measured on the sagittal section using a light microscopic enlargement at 400X the normal view while the morphologic changes of ameloblasts of each zone were observed electron-microscopically. The obtained results were as followed : 1. The length of the region of facing pulp and facing dentin of the zone of presecretion were increased by 11.5% (P<0.01) and 17.7% (P<0.01), respectively. 2. The length of the zone of secretion was increased by 17.3% (P<0.01), but the zone of maturation was decreased by 15.3% (P>0.01). 3. The total length of the zone of amelogenesis was not changed significantly (P>0.05). 4. Electron-microscopically, enlargement of the cell membrane, rER, mitochondria, and nuclear membrane were observed. These changes were mostly severe in the zone of maturation.

  3. Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation

    DEFF Research Database (Denmark)

    Haubek, Dorte; Gjørup, Hans; Jensen, Lillian Gryesten

    2011-01-01

    Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation......Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a danish five-generation family with a novel FAM83H nonsense mutation...

  4. Mutations in the pH-Sensing G-protein-Coupled Receptor GPR68 Cause Amelogenesis Imperfecta.

    Science.gov (United States)

    Parry, David A; Smith, Claire E L; El-Sayed, Walid; Poulter, James A; Shore, Roger C; Logan, Clare V; Mogi, Chihiro; Sato, Koichi; Okajima, Fumikazu; Harada, Akihiro; Zhang, Hong; Koruyucu, Mine; Seymen, Figen; Hu, Jan C-C; Simmer, James P; Ahmed, Mushtaq; Jafri, Hussain; Johnson, Colin A; Inglehearn, Chris F; Mighell, Alan J

    2016-10-06

    Amelogenesis is the process of dental enamel formation, leading to the deposition of the hardest tissue in the human body. This process requires the intricate regulation of ion transport and controlled changes to the pH of the developing enamel matrix. The means by which the enamel organ regulates pH during amelogenesis is largely unknown. We identified rare homozygous variants in GPR68 in three families with amelogenesis imperfecta, a genetically and phenotypically heterogeneous group of inherited conditions associated with abnormal enamel formation. Each of these homozygous variants (a large in-frame deletion, a frameshift deletion, and a missense variant) were predicted to result in loss of function. GPR68 encodes a proton-sensing G-protein-coupled receptor with sensitivity in the pH range that occurs in the developing enamel matrix during amelogenesis. Immunohistochemistry of rat mandibles confirmed localization of GPR68 in the enamel organ at all stages of amelogenesis. Our data identify a role for GPR68 as a proton sensor that is required for proper enamel formation.

  5. Chairside treatment of amelogenesis imperfecta, including establishment of a new vertical dimension with resin nanoceramic and intraoral scanning.

    Science.gov (United States)

    Zimmermann, Moritz; Koller, Christina; Hickel, Reinhard; Kühnisch, Jan

    2016-09-01

    Amelogenesis imperfecta is a hereditary disease affecting the structural development of tooth substance. This clinical report describes a 1-visit chairside treatment of an 8-year-old patient with amelogenesis imperfecta, using computer-aided design and computer-aided manufacturing (CAD-CAM) technology. Intraoral scanning was performed using the Cerec Omnicam. Thirteen resin nanoceramic crowns (Lava Ultimate) were fabricated chairside by using a Cerec MCXL milling unit and seated adhesively. The patient's treatment included establishing a new occlusal vertical dimension and new centric relationship. Reevaluation after 6 months showed a stable situation.

  6. Amelogenesis imperfecta with multiple impacted teeth and skeletal class III malocclusion: complete mouth rehabilitation of a young adult.

    Science.gov (United States)

    Patil, Pravinkumar G; Patil, Smita P

    2014-01-01

    Amelogenesis imperfecta is an autosomal dominant disorder. It is a group of hereditary diseases showing abnormal enamel density and crown malformation. This clinical report describes the oral rehabilitation of a young adult diagnosed with a variant of hypoplastic amelogenesis imperfecta with multiple impacted teeth and skeletal class III malocclusion. The treatment procedures of teeth extractions, endodontic treatment of remaining teeth followed by post and core restorations, esthetic and functional crown lengthening, and metal ceramic fixed dental prostheses were performed sequentially in the maxillary arch. The mandibular arch was restored with an overdenture. One-year follow-up revealed satisfactory results.

  7. Amelogenesis Imperfecta and Generalized Gingival Overgrowth Resembling Hereditary Gingival Fibromatosis in Siblings: A Case Report

    Directory of Open Access Journals (Sweden)

    Emre Yaprak

    2012-01-01

    Full Text Available Amelogenesis imperfecta (AI is a group of hereditary disorders primarily characterized by developmental abnormalities in the quantity and/or quality of enamel. There are some reports suggesting an association between AI and generalized gingival enlargement. This paper describes the clinical findings and oral management of two siblings presenting both AI and hereditary gingival fibromatosis (HGF like generalized gingival enlargements. The treatment of gingival enlargements by periodontal flap surgery was successful in the management of the physiologic gingival form for both patients in the 3-year follow-up period. Prosthetic treatment was also satisfactory for the older patient both aesthetically and functionally.

  8. Expression of steroid receptors in ameloblasts during amelogenesis in rat incisors

    Directory of Open Access Journals (Sweden)

    Sophia Houari

    2016-11-01

    Full Text Available Endocrine disrupting chemicals (EDCs play a part in the modern burst of diseases and interfere with the steroid hormone axis. Bisphenol A (BPA, one of the most active and widely used EDCs, affects ameloblast functions, leading to an enamel hypomineralization pattern similar to that of Molar Incisor Hypomineralization (MIH. In order to explore the molecular pathways stimulated by BPA during amelogenesis, we thoroughly investigated the receptors known to directly or indirectly mediate the effects of BPA. The expression patterns of high affinity BPA receptors (ERRγ, GPR30, of ketosteroid receptors (ERs, AR, PGR, GR, MR, of the retinoid receptor RXRα and PPARγ were established using RT-qPCR analysis of RNAs extracted from microdissected enamel organ of adult rats. Their expression was dependent on the stage of ameloblast differentiation, except that of ERβ and PPARγ which remained undetectable. An additional large scale microarray analysis revealed three main groups of receptors according to their level of expression in maturation stage ameloblasts. The expression level of RXRα was the highest, similar to the vitamin D receptor (VDR, whereas the others were 13 to 612 fold lower, with AR and GR being intermediate. Immunofluorescent analysis of VDR, ERα and AR confirmed their presence mainly in maturation- stage ameloblasts. These data provide further evidence that ameloblasts express a specific combination of hormonal receptors depending on their developmental stage. This study represents the first step towards understanding dental endocrinology as well as some of the effects of EDCs on the pathophysiology of amelogenesis.

  9. Expression of Steroid Receptors in Ameloblasts during Amelogenesis in Rat Incisors.

    Science.gov (United States)

    Houari, Sophia; Loiodice, Sophia; Jedeon, Katia; Berdal, Ariane; Babajko, Sylvie

    2016-01-01

    Endocrine disrupting chemicals (EDCs) play a part in the modern burst of diseases and interfere with the steroid hormone axis. Bisphenol A (BPA), one of the most active and widely used EDCs, affects ameloblast functions, leading to an enamel hypomineralization pattern similar to that of Molar Incisor Hypomineralization (MIH). In order to explore the molecular pathways stimulated by BPA during amelogenesis, we thoroughly investigated the receptors known to directly or indirectly mediate the effects of BPA. The expression patterns of high affinity BPA receptors (ERRγ, GPR30), of ketosteroid receptors (ERs, AR, PGR, GR, MR), of the retinoid receptor RXRα, and PPARγ were established using RT-qPCR analysis of RNAs extracted from microdissected enamel organ of adult rats. Their expression was dependent on the stage of ameloblast differentiation, except that of ERβ and PPARγ which remained undetectable. An additional large scale microarray analysis revealed three main groups of receptors according to their level of expression in maturation-stage ameloblasts. The expression level of RXRα was the highest, similar to the vitamin D receptor (VDR), whereas the others were 13 to 612-fold lower, with AR and GR being intermediate. Immunofluorescent analysis of VDR, ERα and AR confirmed their presence mainly in maturation- stage ameloblasts. These data provide further evidence that ameloblasts express a specific combination of hormonal receptors depending on their developmental stage. This study represents the first step toward understanding dental endocrinology as well as some of the effects of EDCs on the pathophysiology of amelogenesis.

  10. Expression of Steroid Receptors in Ameloblasts during Amelogenesis in Rat Incisors

    Science.gov (United States)

    Houari, Sophia; Loiodice, Sophia; Jedeon, Katia; Berdal, Ariane; Babajko, Sylvie

    2016-01-01

    Endocrine disrupting chemicals (EDCs) play a part in the modern burst of diseases and interfere with the steroid hormone axis. Bisphenol A (BPA), one of the most active and widely used EDCs, affects ameloblast functions, leading to an enamel hypomineralization pattern similar to that of Molar Incisor Hypomineralization (MIH). In order to explore the molecular pathways stimulated by BPA during amelogenesis, we thoroughly investigated the receptors known to directly or indirectly mediate the effects of BPA. The expression patterns of high affinity BPA receptors (ERRγ, GPR30), of ketosteroid receptors (ERs, AR, PGR, GR, MR), of the retinoid receptor RXRα, and PPARγ were established using RT-qPCR analysis of RNAs extracted from microdissected enamel organ of adult rats. Their expression was dependent on the stage of ameloblast differentiation, except that of ERβ and PPARγ which remained undetectable. An additional large scale microarray analysis revealed three main groups of receptors according to their level of expression in maturation-stage ameloblasts. The expression level of RXRα was the highest, similar to the vitamin D receptor (VDR), whereas the others were 13 to 612-fold lower, with AR and GR being intermediate. Immunofluorescent analysis of VDR, ERα and AR confirmed their presence mainly in maturation- stage ameloblasts. These data provide further evidence that ameloblasts express a specific combination of hormonal receptors depending on their developmental stage. This study represents the first step toward understanding dental endocrinology as well as some of the effects of EDCs on the pathophysiology of amelogenesis. PMID:27853434

  11. KohlschutterTonz Syndrome : Mutations in ROGDI and Evidence of Genetic Heterogeneity

    NARCIS (Netherlands)

    Tucci, Arianna; Kara, Eleanna; Schossig, Anna; Wolf, Nicole I.; Plagnol, Vincent; Fawcett, Katherine; Paisan-Ruiz, Coro; Moore, Matthew; Hernandez, Dena; Musumeci, Sebastiano; Tennison, Michael; Hennekam, Raoul; Palmeri, Silvia; Malandrini, Alessandro; Raskin, Salmo; Donnai, Dian; Hennig, Corina; Tzschach, Andreas; Hordijk, Roel; Bast, Thomas; Wimmer, Katharina; Lo, Chien-Ning; Shorvon, Simon; Mefford, Heather; Eichler, Evan E.; Hall, Roger; Hayes, Ian; Hardy, John; Singleton, Andrew; Zschocke, Johannes; Houlden, Henry

    2013-01-01

    KohlschutterTonz syndrome (KTS) is a rare autosomal recessive disorder characterized by amelogenesis imperfecta, psychomotor delay or regression and seizures starting early in childhood. KTS was established as a distinct clinical entity after the first report by Kohlschutter in 1974, and to date, on

  12. Restoring function and esthetics in a patient with amelogenesis imperfecta: a case report.

    Science.gov (United States)

    Sengun, Abdulkadir; Ozer, Füsun

    2002-03-01

    Amelogenesis imperfecta is a hereditary disorder that affects enamel on primary and permanent teeth. It is a rare dental disease but represents a major restorative challenge for the dentist. A 14-year-old boy presented with sensitive, discolored, and mutilated teeth and a decreased vertical dimension of occlusion. The aim of treatment was to reduce dental sensitivity, to restore esthetics, and to correct the vertical dimension of occlusion. To modify the occlusion, and to protect the dentin from chemical and thermal attacks, nickel-chrome onlays were placed on the molars. To improve the esthetics of the incisors and premolars, resin composite restorations were applied. The patient was regularly recalled during the postoperative period. Radiographic and clinical examinations 10 months posttreatment revealed no evidence of disorders associated with the restored teeth or their supporting structures.

  13. Interdisciplinary management for restoration of function and esthetics in a patient with hereditary amelogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Sushma Dhiman

    2015-01-01

    Full Text Available Amelogenesis imperfecta (AI is a type of the hereditary disorder which is expressed as a group of conditions causing developmental alterations in the structure of enamel. It is associated with a reduction of oral health-related quality-of-life, has an impact on psychological well-being, and leads to various physiological problems. Children or adults with AI express varying degree of malocclusions either in the form of crowding, impacted teeth, spacing, retained teeth, reduced vertical height due to abnormal tooth structure or undue tooth loss. Orthodontic treatment should precede esthetic rehabilitation. Proper diagnosis of the case is quintessential to provide durable functional and esthetic result to these patients, improving the quality of their lives. We present a case of interdisciplinary management for restoring function and esthetics in a patient with hereditary AI of the hypoplastic type accompanied with tooth impaction and some other dental anomalies.

  14. Satisfaction After Restoring Aesthetics and Function in a Child with Amelogenesis Imperfecta: A Case Report

    Directory of Open Access Journals (Sweden)

    Nihal Özcan

    2016-08-01

    Full Text Available Amelogenesis imperfecta (AI is a hereditary disorder that disrupts the formation of enamel in both primary and permanent dentition. Management of AI is a challenge for the patient and the clinician. This case report presents the management of AI in a six-year-old female patient. Considering the patient’s age, we decided to make removable dentures in order to avoid growth and development problems. Conventional complete dentures were made, vertical dimension was increased, and the desired aesthetics and function were gained. Additionally, satisfaction with prosthodontic rehabilitation was evaluated using a questionnaire. A high level of patient and parent satisfaction was obtained. Treatment planning for patients with AI is related to many factors including the age and socioeconomic status of the patient, the type and severity of the disorder, the intraoral situation at the time the treatment is planned and most importantly, cooperation of the patient plays a major role.

  15. Exclusion of known gene for enamel development in two Brazilian families with amelogenesis imperfecta.

    Science.gov (United States)

    Santos, Maria C L G; Hart, P Suzanne; Ramaswami, Mukundhan; Kanno, Cláudia M; Hart, Thomas C; Line, Sergio R P

    2007-01-31

    Amelogenesis imperfecta (AI) is a genetically heterogeneous group of diseases that result in defective development of tooth enamel. Mutations in several enamel proteins and proteinases have been associated with AI. The object of this study was to evaluate evidence of etiology for the six major candidate gene loci in two Brazilian families with AI. Genomic DNA was obtained from family members and all exons and exon-intron boundaries of the ENAM, AMBN, AMELX, MMP20, KLK4 and Amelotin gene were amplified and sequenced. Each family was also evaluated for linkage to chromosome regions known to contain genes important in enamel development. The present study indicates that the AI in these two families is not caused by any of the known loci for AI or any of the major candidate genes proposed in the literature. These findings indicate extensive genetic heterogeneity for non-syndromic AI.

  16. Exclusion of known gene for enamel development in two Brazilian families with amelogenesis imperfecta

    Directory of Open Access Journals (Sweden)

    Hart Thomas C

    2007-01-01

    Full Text Available Abstract Amelogenesis imperfecta (AI is a genetically heterogeneous group of diseases that result in defective development of tooth enamel. Mutations in several enamel proteins and proteinases have been associated with AI. The object of this study was to evaluate evidence of etiology for the six major candidate gene loci in two Brazilian families with AI. Genomic DNA was obtained from family members and all exons and exon-intron boundaries of the ENAM, AMBN, AMELX, MMP20, KLK4 and Amelotin gene were amplified and sequenced. Each family was also evaluated for linkage to chromosome regions known to contain genes important in enamel development. The present study indicates that the AI in these two families is not caused by any of the known loci for AI or any of the major candidate genes proposed in the literature. These findings indicate extensive genetic heterogeneity for non-syndromic AI.

  17. Full mouth rehabilitation of a patient with amelogenesis imperfecta: a case report.

    Science.gov (United States)

    Rajesh, P; Prasad, Maruthi; Haldal, Sindhu

    2014-07-01

    Amelogenesis imperfecta (AI) is a hereditary disorder expressing a group of conditions which cause developmental alterations in the structure of enamel. This disorder has an adverse impact on oral health and also hampers the quality of life of the individual causing physiologic problems. The treatment of such patients would not only upgrade their quality-of-life, but also improve their self-esteem. The correction of such severely worn out dentition may require extensive restorative treatment to achieve appropriate results. It is important to identify the factors that contribute to the excessive wear and loss of vertical dimension. The correction of the defects has to be done without violating the biologic or mechanical principles. Full mouth rehabilitation in such patients improves esthetics, function and comfort. The following case report presents a systematic approach in rehabilitating a case of AI hypoplastic type using full mouth metal reinforced porcelain restorations.

  18. Novel ENAM and LAMB3 mutations in Chinese families with hypoplastic amelogenesis imperfecta.

    Directory of Open Access Journals (Sweden)

    Xin Wang

    Full Text Available Amelogenesis imperfecta is a group of inherited diseases affecting the quality and quantity of dental enamel. To date, mutations in more than ten genes have been associated with non-syndromic amelogenesis imperfecta (AI. Among these, ENAM and LAMB3 mutations are known to be parts of the etiology of hypoplastic AI in human cases. When both alleles of LAMB3 are defective, it could cause junctional epidermolysis bullosa (JEB, while with only one mutant allele in the C-terminus of LAMB3, it could result in severe hypoplastic AI without skin fragility. We enrolled three Chinese families with hypoplastic autosomal-dominant AI. Despite the diagnosis falling into the same type, the characteristics of their enamel hypoplasia were different. Screening of ENAM and LAMB3 genes was performed by direct sequencing of genomic DNA from blood samples. Disease-causing mutations were identified and perfectly segregated with the enamel defects in three families: a 19-bp insertion mutation in the exon 7 of ENAM (c.406_407insTCAAAAAAGCCGACCACAA, p.K136Ifs*16 in Family 1, a single-base deletion mutation in the exon 5 of ENAM (c. 139delA, p. M47Cfs*11 in Family 2, and a LAMB3 nonsense mutation in the last exon (c.3466C>T, p.Q1156X in Family 3. Our results suggest that heterozygous mutations in ENAM and LAMB3 genes can cause hypoplastic AI with markedly different phenotypes in Chinese patients. And these findings extend the mutation spectrum of both genes and can be used for mutation screening of AI in the Chinese population.

  19. Novel ENAM and LAMB3 mutations in Chinese families with hypoplastic amelogenesis imperfecta.

    Science.gov (United States)

    Wang, Xin; Zhao, Yuming; Yang, Yuan; Qin, Man

    2015-01-01

    Amelogenesis imperfecta is a group of inherited diseases affecting the quality and quantity of dental enamel. To date, mutations in more than ten genes have been associated with non-syndromic amelogenesis imperfecta (AI). Among these, ENAM and LAMB3 mutations are known to be parts of the etiology of hypoplastic AI in human cases. When both alleles of LAMB3 are defective, it could cause junctional epidermolysis bullosa (JEB), while with only one mutant allele in the C-terminus of LAMB3, it could result in severe hypoplastic AI without skin fragility. We enrolled three Chinese families with hypoplastic autosomal-dominant AI. Despite the diagnosis falling into the same type, the characteristics of their enamel hypoplasia were different. Screening of ENAM and LAMB3 genes was performed by direct sequencing of genomic DNA from blood samples. Disease-causing mutations were identified and perfectly segregated with the enamel defects in three families: a 19-bp insertion mutation in the exon 7 of ENAM (c.406_407insTCAAAAAAGCCGACCACAA, p.K136Ifs*16) in Family 1, a single-base deletion mutation in the exon 5 of ENAM (c. 139delA, p. M47Cfs*11) in Family 2, and a LAMB3 nonsense mutation in the last exon (c.3466C>T, p.Q1156X) in Family 3. Our results suggest that heterozygous mutations in ENAM and LAMB3 genes can cause hypoplastic AI with markedly different phenotypes in Chinese patients. And these findings extend the mutation spectrum of both genes and can be used for mutation screening of AI in the Chinese population.

  20. Treatment plan in amelogenesis imperfecta: A structured literature review on treatment protocols and dedicating the best possible options

    Directory of Open Access Journals (Sweden)

    Azari A.

    2008-12-01

    Full Text Available "nAmelogenesis imperfecta is an inherited disease that disturbs the formation of the enamel. It occurs as two main categories, hypomineralized and hypoplastic. Both deciduous and permanent teeth are affected, and the disorder may create unaesthetic appearance, dental sensitivity, and severe attrition. In this article through performing a structured literature review, numerous treatment modalities which so far advocated in rehabilitation of amelogenesis imperfecta in adults and children is discussed. The progressive changes on open bite, the problem of bonding during restorative phase of treatment , the rehabilitation difficulties of deciduous as well as permanent teeth is also discussed in detail and finally the interdisciplinary approach for treatment of this disability is demonstrated and some points for decision making in treatment protocols are suggested.

  1. Rehabilitation of a patient with amelogenesis imperfecta using porcelain veneers and CAD/CAM polymer restorations: A clinical report.

    Science.gov (United States)

    Saeidi Pour, Reza; Edelhoff, Daniel; Prandtner, Otto; Liebermann, Anja

    2015-01-01

    The complete dental rehabilitation of patients with a vertical dimension loss (VDL) caused by structural enamel deficits associated with amelogenesis imperfecta (AI) represents a difficult challenge for restorative teams. Accurate analysis and treatment planning that includes esthetic and functional evaluations and adequate material selection are important prerequisites for successful results. Long-term provisional restorations play an important role in exploring and elucidating the patients' esthetic demands and functional needs. Restorative treatment options can vary from requiring only oral hygiene instructions to extensive dental restorations that include composite fillings, ceramic veneers, metal-ceramic, or all-ceramic crowns. This case report describes a full-mouth rehabilitation of a patient with amelogenesis imperfecta including the case planning, bite replacement, preparation, and restoration setting steps with an experimental CAD/CAM polymer and porcelain veneers.

  2. Androgen Receptor Involvement in Rat Amelogenesis: An Additional Way for Endocrine-Disrupting Chemicals to Affect Enamel Synthesis.

    Science.gov (United States)

    Jedeon, Katia; Loiodice, Sophia; Salhi, Khaled; Le Normand, Manon; Houari, Sophia; Chaloyard, Jessica; Berdal, Ariane; Babajko, Sylvie

    2016-11-01

    Endocrine-disrupting chemicals (EDCs) that interfere with the steroid axis can affect amelogenesis, leading to enamel hypomineralization similar to that of molar incisor hypomineralization, a recently described enamel disease. We investigated the sex steroid receptors that may mediate the effects of EDCs during rat amelogenesis. The expression of androgen receptor (AR), estrogen receptor (ER)-α, and progesterone receptor was dependent on the stage of ameloblast differentiation, whereas ERβ remained undetectable. AR was the only receptor selectively expressed in ameloblasts involved in final enamel mineralization. AR nuclear translocation and induction of androgen-responsive element-containing promoter activity upon T treatment, demonstrated ameloblast responsiveness to androgens. T regulated the expression of genes involved in enamel mineralization such as KLK4, amelotin, SLC26A4, and SLC5A8 but not the expression of genes encoding matrix proteins, which determine enamel thickness. Vinclozolin and to a lesser extent bisphenol A, two antiandrogenic EDCs that cause enamel defects, counteracted the actions of T. In conclusion, we show, for the first time, the following: 1) ameloblasts express AR; 2) the androgen signaling pathway is involved in the enamel mineralization process; and 3) EDCs with antiandrogenic effects inhibit AR activity and preferentially affect amelogenesis in male rats. Their action, through the AR pathway, may specifically and irreversibly affect enamel, potentially leading to the use of dental defects as a biomarker of exposure to environmental pollutants. These results are consistent with the steroid hormones affecting ameloblasts, raising the issue of the hormonal influence on amelogenesis and possible sexual dimorphism in enamel quality.

  3. Amelogenesis imperfecta

    Science.gov (United States)

    ... 2016 Updated by: Michael Kapner, DDS, general and aesthetic dentistry, Norwalk Medical Center, Norwalk, CT. Review provided ... for EHRs For Developers U.S. National Library of Medicine 8600 Rockville Pike, Bethesda, MD 20894 U.S. Department ...

  4. Identification of mutations in SLC24A4, encoding a potassium-dependent sodium/calcium exchanger, as a cause of amelogenesis imperfecta.

    Science.gov (United States)

    Parry, David A; Poulter, James A; Logan, Clare V; Brookes, Steven J; Jafri, Hussain; Ferguson, Christopher H; Anwari, Babra M; Rashid, Yasmin; Zhao, Haiqing; Johnson, Colin A; Inglehearn, Chris F; Mighell, Alan J

    2013-02-07

    A combination of autozygosity mapping and exome sequencing identified a null mutation in SLC24A4 in a family with hypomineralized amelogenesis imperfect a (AI), a condition in which tooth enamel formation fails. SLC24A4 encodes a calcium transporter upregulated in ameloblasts during the maturation stage of amelogenesis. Screening of further AI families identified a missense mutation in the ion-binding site of SLC24A4 expected to severely diminish or abolish the ion transport function of the protein. Furthermore, examination of previously generated Slc24a4 null mice identified a severe defect in tooth enamel that reflects impaired amelogenesis. These findings support a key role for SLC24A4 in calcium transport during enamel formation.

  5. A new locus for autosomal dominant amelogenesis imperfecta on chromosome 8q24.3.

    Science.gov (United States)

    Mendoza, Gustavo; Pemberton, Trevor J; Lee, Kwanghyuk; Scarel-Caminaga, Raquel; Mehrian-Shai, Ruty; Gonzalez-Quevedo, Catalina; Ninis, Vasiliki; Hartiala, Jaana; Allayee, Hooman; Snead, Malcolm L; Leal, Suzanne M; Line, Sergio R P; Patel, Pragna I

    2007-01-01

    Amelogenesis imperfecta (AI) is a collective term used to describe phenotypically diverse forms of defective tooth enamel development. AI has been reported to exhibit a variety of inheritance patterns, and several loci have been identified that are associated with AI. We have performed a genome-wide scan in a large Brazilian family segregating an autosomal dominant form of AI and mapped a novel locus to 8q24.3. A maximum multipoint LOD score of 7.5 was obtained at marker D8S2334 (146,101,309 bp). The disease locus lies in a 1.9 cM (2.1 Mb) region according to the Rutgers Combined Linkage-Physical map, between a VNTR marker (at 143,988,705 bp) and the telomere (146,274,826 bp). Ten candidate genes were identified based on gene ontology and microarray-facilitated gene selection using the expression of murine orthologues in dental tissue, and examined for the presence of a mutation. However, no causative mutation was identified.

  6. Typical Features of Amelogenesis Imperfecta in Two Patients with Bartter’s Syndrome

    Directory of Open Access Journals (Sweden)

    Hercílio Martelli-Júnior

    2012-12-01

    Full Text Available Background/Aims: Amelogenesis imperfecta (AI is due to many inherited defects of enamel formation that affect the quantity and quality of enamel, leading to delay in tooth eruption and cosmetic consequences. AI has been described in association with nephrocalcinosis, which is called the enamel-renal syndrome. The aim of this case report is to describe typical features of AI in 2 patients with Bartter’s syndrome (BS for the first time. Methods: -Eight patients with confirmed BS were systematically screened for dental abnormalities as part of protocol. Those with suggestive clinical features of AI were submitted to panoramic X-ray and decayed teeth were analyzed by scanning electron microscopy. Results: Typical features of AI were detected in 2 girls with BS. These 2 patients showed nephrocalcinosis, and diagnosis and adequate clinical control were delayed. Genetic analysis detected the mutation responsible for BS in 1 of these patients. In this case, BS was due to a homozygous mutation of exon 5 of the KCNJ1 gene resulting in a substitution of valine for alanine at the codon 214 (A214V. Conclusions: The finding of typical features of AI in BS might constitute preliminary evidence that abnormalities of the biomineralization process found in patients with renal tubular disorders might also affect calcium deposition in dental tissues.

  7. Amelogenesis Imperfecta: Rehabilitation and Brainstorming on the Treatment Outcome after the First Year

    Directory of Open Access Journals (Sweden)

    Ayça Deniz İzgi

    2015-01-01

    Full Text Available Amelogenesis imperfecta (AI affects enamel on primary and permanent dentition. This hereditary disorder is characterized by loss of enamel, poor esthetics, and hypersensitivity. Functional and cosmetic rehabilitation is challenging with variety of treatment options. This report presents the treatment of an AI patient using conventional fixed dentures and discusses issues related to posttreatment complications and prosthetic treatment outcome after 1 year of follow-up. A 19-year-old male AI patient with impaired self-esteem presented with hypersensitive, discolored, and mutilated teeth. Clinical examination revealed compromised occlusion and anterior open-bite. After hygiene maintenance full-coverage porcelain-fused-to-metal fixed restorations were indicated and applied. At the end of the treatment acceptable functional and esthetic results could be achieved. However, nearly a year after treatment a gingival inflammation in the esthetic zone complicated the outcome. Insufficient oral hygiene was to be blamed. Tooth sensitivity present from early childhood in these patients may prevent oral hygiene from becoming a habit. The relaxation due to relieve of hypersensitivity after treatment makes oral hygiene learning difficult. Continuous oral hygiene maintenance motivation may be crucial for the success of the treatment of AI patients. Treatment of AI patients should be carefully planned and an acceptable risk-benefit balance should be established.

  8. Changes in amelogenesis in the rat incisor following short-term hypocalcaemia.

    Science.gov (United States)

    Yamaguti, Paulo M; Arana-Chavez, Victor E; Acevedo, Ana Carolina

    2005-02-01

    There is a relationship between hypocalcaemia and the enamel hypoplasia. Earlier studies in rats have reported a severe hypocalcaemia and enamel hypoplasia a month after thyro-parathyroidectomy (TPTX). The aims of this study were to look at earlier stages and to attempt to correlate morphological changes with alterations in the distribution of amelogenin. Twenty-five Wistar rats were, under anaesthesia, thyro-parathyroidectomized. Sham operated rats were included as controls. After 14, 30 or 57 days, the animals were reanesthatized and the tissues fixed by intracardiac perfusion of fixative. The lower incisors were processed for light microscopy and immunogold electron microscopy. After 14 days the thyro-parathyroidectomised rats were severely hypocalcaemic but amelogenesis was morphologically similar to controls. After 30 and 57 days, enamel defects were observed in the late secretory and early maturation stages in the thyro-parathyroidectomised rats. The immunocytochemical study revealed a concentration of stippled material immunolabelled for amelogenin at the secretory pole of the ameloblasts in the hypocalcaemic rats. The absence of enamel defects after 14 days suggests that this was an insufficient hypocalcaemic period to induce morphological alterations. The concentration of stippled material containing amelogenin suggests that alterations in matrix formation may be the basis of the morphological changes.

  9. Deletion of amelotin exons 3–6 is associated with amelogenesis imperfecta

    Science.gov (United States)

    Smith, Claire E.L.; Murillo, Gina; Brookes, Steven J.; Poulter, James A.; Silva, Sandra; Kirkham, Jennifer; Inglehearn, Chris F.; Mighell, Alan J.

    2016-01-01

    Amelogenesis imperfecta (AI) is a heterogeneous group of genetic conditions that result in defective dental enamel formation. Amelotin (AMTN) is a secreted protein thought to act as a promoter of matrix mineralization in the final stage of enamel development, and is strongly expressed, almost exclusively, in maturation stage ameloblasts. Amtn overexpression and Amtn knockout mouse models have defective enamel with no other associated phenotypes, highlighting AMTN as an excellent candidate gene for human AI. However, no AMTN mutations have yet been associated with human AI. Using whole exome sequencing, we identified an 8,678 bp heterozygous genomic deletion encompassing exons 3-6 of AMTN in a Costa Rican family segregating dominant hypomineralised AI. The deletion corresponds to an in-frame deletion of 92 amino acids, shortening the protein from 209 to 117 residues. Exfoliated primary teeth from an affected family member had enamel that was of a lower mineral density compared to control enamel and exhibited structural defects at least some of which appeared to be associated with organic material as evidenced using elemental analysis. This study demonstrates for the first time that AMTN mutations cause non-syndromic human AI and explores the human phenotype, comparing it with that of mice with disrupted Amtn function. PMID:27412008

  10. Effect of calcium, given before or after a fluoride insult, on hamster secretory amelogenesis in vitro.

    Science.gov (United States)

    Bronckers, Antonius L J J; Bervoets, Theodorus J M; Wöltgens, Joseph H M; Lyaruu, Donacian M

    2006-05-01

    We tested the hypothesis that high-calcium medium given prior to or immediately after exposure to fluoride (F) reduces the negative effects of F on secretory amelogenesis. Hamster molar tooth germs were grown in organ culture in media with different calcium levels. Deposition of enamel matrix and matrix mineralization were monitored by incorporation of [3H]proline and uptake of 45Ca and acid-soluble 32PO4. Ameloblast structure and the occurrence of a fluorotic enamel matrix were examined by light and electron microscopy. A preculture of explants in high-calcium medium partially prevented the formation of fluorotic (non-mineralizing) enamel matrix, increased matrix secretion but could not prevent F-induced hypermineralization of the pre-exposure enamel. High-calcium medium, applied after F insult, accelerated the recovery of fluorotic matrix, improved ameloblast structure, enhanced amelogenin secretion, and increased enamel thickness. The data indicate that it might be the balance between the amount of mineral deposition and that of matrix secretion which is critical for the mineralization of newly secreted enamel. Exposure to F disturbs this balance by enhancing mineralization of the pre-exposure enamel, probably generating an excess of protons. High calcium may protect against F exposure by enhancing amelogenin secretion into the enamel space, thereby increasing the local buffering capacity at the mineralization front.

  11. Aesthetic and Functional Rehabilitation of the Primary Dentition Affected by Amelogenesis Imperfecta

    Directory of Open Access Journals (Sweden)

    Maria Carolina Salomé Marquezin

    2015-01-01

    Full Text Available The objective of this case report was to describe the oral rehabilitation of a five-year-old boy patient diagnosed with amelogenesis imperfecta (AI in the primary dentition. AI is a group of hereditary disorders that affects the enamel structure. The patient was brought to the dental clinic complaining of tooth hypersensitivity during meals. The medical history and clinical examination were used to arrive at the diagnosis of AI. The treatment was oral rehabilitation of the primary molars with stainless steel crowns and resin-filled celluloid forms. The main objectives of the selected treatment were to enhance the esthetics, restore masticatory function, and eliminate the teeth sensitivity. The child was monitored in the pediatric dentistry clinic at four-month intervals until the mixed dentition stage. Treatment not only restored function and esthetic, but also showed a positive psychological impact and thereby improved perceived quality of life. The preventive, psychological, and curative measures of a young child with AI were successful. This result can encourage the clinicians to seek a cost-effective technique such as stainless steel crowns, and resin-filled celluloid forms to reestablish the oral functions and improve the child’s psychosocial development.

  12. Endoplasmic reticulum stress in amelogenesis imperfecta and phenotypic rescue using 4-phenylbutyrate.

    Science.gov (United States)

    Brookes, Steven J; Barron, Martin J; Boot-Handford, Ray; Kirkham, Jennifer; Dixon, Michael J

    2014-05-01

    Inherited diseases caused by genetic mutations can arise due to loss of protein function. Alternatively, mutated proteins may mis-fold, impairing endoplasmic reticulum (ER) trafficking, causing ER stress and triggering the unfolded protein response (UPR). The UPR attempts to restore proteostasis but if unsuccessful drives affected cells towards apoptosis. Previously, we reported that in mice, the p.Tyr64His mutation in the enamel extracellular matrix (EEM) protein amelogenin disrupts the secretory pathway in the enamel-forming ameloblasts, resulting in eruption of malformed tooth enamel that phenocopies human amelogenesis imperfecta (AI). Defective amelogenin post-secretory self-assembly and processing within the developing EEM has been suggested to underlie the pathogenesis of X chromosome-linked AI. Here, we challenge this concept by showing that AI pathogenesis associated with the p.Tyr64His amelogenin mutation involves ameloblast apoptosis induced by ER stress. Furthermore, we show that 4-phenylbutyrate can rescue the enamel phenotype in affected female mice by promoting cell survival over apoptosis such that they are able to complete enamel formation despite the presence of the mutation, offering a potential therapeutic option for patients with this form of AI and emphasizing the importance of ER stress in the pathogenesis of this inherited conformational disease.

  13. Amelogenesis Imperfecta: Rehabilitation and Brainstorming on the Treatment Outcome after the First Year

    Science.gov (United States)

    İzgi, Ayça Deniz; Kale, Ediz; Niğiz, Remzi

    2015-01-01

    Amelogenesis imperfecta (AI) affects enamel on primary and permanent dentition. This hereditary disorder is characterized by loss of enamel, poor esthetics, and hypersensitivity. Functional and cosmetic rehabilitation is challenging with variety of treatment options. This report presents the treatment of an AI patient using conventional fixed dentures and discusses issues related to posttreatment complications and prosthetic treatment outcome after 1 year of follow-up. A 19-year-old male AI patient with impaired self-esteem presented with hypersensitive, discolored, and mutilated teeth. Clinical examination revealed compromised occlusion and anterior open-bite. After hygiene maintenance full-coverage porcelain-fused-to-metal fixed restorations were indicated and applied. At the end of the treatment acceptable functional and esthetic results could be achieved. However, nearly a year after treatment a gingival inflammation in the esthetic zone complicated the outcome. Insufficient oral hygiene was to be blamed. Tooth sensitivity present from early childhood in these patients may prevent oral hygiene from becoming a habit. The relaxation due to relieve of hypersensitivity after treatment makes oral hygiene learning difficult. Continuous oral hygiene maintenance motivation may be crucial for the success of the treatment of AI patients. Treatment of AI patients should be carefully planned and an acceptable risk-benefit balance should be established. PMID:26783475

  14. A Randomized Controlled Trial of Crown Therapy in Young Individuals with Amelogenesis Imperfecta.

    Science.gov (United States)

    Pousette Lundgren, G; Morling Vestlund, G I; Trulsson, M; Dahllöf, G

    2015-08-01

    Amelogenesis imperfecta (AI) is a rare, genetically determined defect in enamel mineralization. Existing treatment recommendations suggest resin-composite restorations until adulthood, although such restorations have a limited longevity. New crown materials allow for minimal preparation techniques. The aim of this study was to compare the quality and longevity of 2 crown types-Procera and IPS e.max Press-in adolescents and young adults with AI. A secondary aim was to document adverse events. We included 27 patients (11 to 22 y of age) with AI in need of crown therapy in a randomized controlled trial using a split-mouth technique. After placing 119 Procera crowns and 108 IPS e.max Press crowns following randomization, we recorded longevity, quality, adverse events, and tooth sensitivity. After 2 y, 97% of the crowns in both crown groups had excellent or acceptable quality. We found no significant differences in quality between Procera and IPS e.max Press crowns. Tooth sensitivity was significantly reduced after crown therapy (P < 0.001). Endodontic complications occurred in 3% of crowns. The results show that it is possible to perform crown therapy with excellent results and without severe complications in young patients with AI. The study is registered at http://www.controlled-trials.com (ISRCTN70438627).

  15. Amelogenesis Imperfecta: Rehabilitation and Brainstorming on the Treatment Outcome after the First Year.

    Science.gov (United States)

    İzgi, Ayça Deniz; Kale, Ediz; Niğiz, Remzi

    2015-01-01

    Amelogenesis imperfecta (AI) affects enamel on primary and permanent dentition. This hereditary disorder is characterized by loss of enamel, poor esthetics, and hypersensitivity. Functional and cosmetic rehabilitation is challenging with variety of treatment options. This report presents the treatment of an AI patient using conventional fixed dentures and discusses issues related to posttreatment complications and prosthetic treatment outcome after 1 year of follow-up. A 19-year-old male AI patient with impaired self-esteem presented with hypersensitive, discolored, and mutilated teeth. Clinical examination revealed compromised occlusion and anterior open-bite. After hygiene maintenance full-coverage porcelain-fused-to-metal fixed restorations were indicated and applied. At the end of the treatment acceptable functional and esthetic results could be achieved. However, nearly a year after treatment a gingival inflammation in the esthetic zone complicated the outcome. Insufficient oral hygiene was to be blamed. Tooth sensitivity present from early childhood in these patients may prevent oral hygiene from becoming a habit. The relaxation due to relieve of hypersensitivity after treatment makes oral hygiene learning difficult. Continuous oral hygiene maintenance motivation may be crucial for the success of the treatment of AI patients. Treatment of AI patients should be carefully planned and an acceptable risk-benefit balance should be established.

  16. An autosomal recessive syndrome of severe mental retardation, cataract, coloboma and kyphosis maps to the pericentromeric region of chromosome 4.

    Science.gov (United States)

    Kahrizi, Kimia; Najmabadi, Hossein; Kariminejad, Roxana; Jamali, Payman; Malekpour, Mahdi; Garshasbi, Masoud; Ropers, Hans Hilger; Kuss, Andreas Walter; Tzschach, Andreas

    2009-01-01

    We report on three siblings with a novel mental retardation (MR) syndrome who were born to distantly related Iranian parents. The clinical problems comprised severe MR, cataracts with onset in late adolescence, kyphosis, contractures of large joints, bulbous nose with broad nasal bridge, and thick lips. Two patients also had uni- or bilateral iris coloboma. Linkage analysis revealed a single 10.4 Mb interval of homozygosity with significant LOD score in the pericentromeric region of chromosome 4 flanked by SNPs rs728293 (4p12) and rs1105434 (4q12). This interval contains more than 40 genes, none of which has been implicated in MR so far. The identification of the causative gene defect for this syndrome will provide new insights into the development of the brain and the eye.

  17. Hypomorphic mutations in PGAP2, encoding a GPI-anchor-remodeling protein, cause autosomal-recessive intellectual disability

    DEFF Research Database (Denmark)

    Hansen, Lars; Tawamie, Hasan; Murakami, Yoshiko

    2013-01-01

    PGAP2 encodes a protein involved in remodeling the glycosylphosphatidylinositol (GPI) anchor in the Golgi apparatus. After synthesis in the endoplasmic reticulum (ER), GPI anchors are transferred to the proteins and are remodeled while transported through the Golgi to the cell membrane. Germline...... rescue when we used strong promoters before the mutant cDNAs, suggesting a hypomorphic effect of the mutations. We report on alterations in the Golgi-located part of the GPI-anchor-biosynthesis pathway and extend the phenotypic spectrum of the GPI-anchor deficiencies to isolated intellectual disability...

  18. Two cases of autosomal recessive generalized dystonia in childhood: 5 year follow-up and bilateral globus pallidus stimulation results

    NARCIS (Netherlands)

    Lenders, Mathieu W.; Vergouwen, Mervyn D.; Hageman, Gerard; Hoek, van der Joffrey A.; Ippel, Elly F.; Jansen Steur, Ernst N.; Buschman, Hendrik P.J.; Hariz, Marwan

    2006-01-01

    We report two brothers with an unknown form of early-onset familiar dystonia. Characteristic clinical features are (1) childhood-onset; (2) extrapyramidal motor symptoms; (3) dysarthria; and (4) mental retardation. Additional findings include loss of D2-receptors in both basal ganglia and hypoplasia

  19. Autosomal recessive mental retardation, deafness, ankylosis, and mild hypophosphatemia associated with a novel ANKH mutation in a consanguineous family

    NARCIS (Netherlands)

    Morava, E.; Kuhnisch, J.; Drijvers, J.M.; Robben, J.H.; Cremers, C.W.R.J.; Setten, P. van; Branten, A.J.W.; Stumpp, S.; Jong, A. de; Voesenek, K.E.J.; Vermeer, S.; Heister, A.; Claahsen-van der Grinten, H.L.; O'Neill, C.W.; Willemsen, M.H.; Lefeber, D.J.; Deen, P.M.T.; Kornak, U.; Kremer, J.M.J.; Wevers, R.A.

    2011-01-01

    CONTEXT: Mutations in ANKH cause the highly divergent conditions familial chondrocalcinosis and craniometaphyseal dysplasia. The gene product ANK is supposed to regulate tissue mineralization by transporting pyrophosphate to the extracellular space. OBJECTIVE: We evaluated several family members of

  20. A novel mutation in the sterol 27-hydroxylase gene of a woman with autosomal recessive cerebrotendinous xanthomatosis

    Directory of Open Access Journals (Sweden)

    Garuti Rita

    2010-10-01

    Full Text Available Article abstract Mutations of the gene encoding the mitochondrial enzyme sterol 27-hydroxylase (CYP27A1 gene cause defects in the cholesterol pathway to bile acids that lead to the storage of cholestanol and cholesterol in tendons, lenses and the central nervous system. This disorder is the cause of a clinical syndrome known as cerebrotendinous xanthomatosis (CTX. Since 1991 several mutations of the CYP27A1 gene have been reported. We diagnosed the clinical features of CTX in a caucasian woman. Serum levels of cholestanol and 7α-hydroxycholesterol were elevated and the concentration of 27-hydroxycholesterol was reduced. Bile alcohols in the urine and faeces were increased. The analysis of the CYP27A1 gene showed that the patient was a compound heterozygote carrying two mutations both located in exon 8. One mutation is a novel four nucleotide deletion (c.1330-1333delTTCC that results in a frameshift and the occurrence of a premature stop codon leading to the formation of a truncated protein of 448 amino acids. The other mutation, previously reported, is a C - > T transition (c. c.1381C > T that converts the glutamine codon at position 461 into a termination codon (p.Q461X. These truncated proteins are expected to have no biological function being devoid of the cysteine residue at position 476 of the normal enzyme that is crucial for heme binding and enzyme activity.

  1. Whole-exome sequencing reveals ZNF408 as a new gene associated with autosomal recessive retinitis pigmentosa with vitreal alterations

    NARCIS (Netherlands)

    Avila-Fernandez, A.; Perez-Carro, R.; Corton, M.; Lopez-Molina, M.I.; Campello, L.; Garanto, A.; Fernandez-Sanchez, L.; Duijkers, L.; Lopez-Martinez, M.A.; Riveiro-Alvarez, R.; Silva, L.R. Da; Sanchez-Alcudia, R.; Martin-Garrido, E.; Reyes, N.; Garcia-Garcia, F.; Dopazo, J.; Garcia-Sandoval, B.; Collin, R.W.J.; Cuenca, N.; Ayuso, C.

    2015-01-01

    Retinitis pigmentosa (RP) is a group of progressive inherited retinal dystrophies that cause visual impairment as a result of photoreceptor cell death. RP is heterogeneous, both clinically and genetically making difficult to establish precise genotype-phenotype correlations. In a Spanish family with

  2. A Novel Mutation in the EDAR Gene Causes Severe Autosomal Recessive Hypohidrotic Ectodermal Dysplasia

    DEFF Research Database (Denmark)

    Henningsen, Emil; Svendsen, Mathias Tiedemann; Lildballe, D. L.;

    2014-01-01

    nasal discharge. The girl was the second born child of first-cousin immigrants from Northern Iraq. A novel homozygous mutation (c.84delC) in the EDAR gene was identified. This mutation most likely causes a frameshift in the protein product (p.S29fs*74). This results in abolition of all ectodysplasin...

  3. X-Linked and Autosomal Recessive Alport Syndrome: Pathogenic Variant Features and Further Genotype-Phenotype Correlations.

    Science.gov (United States)

    Savige, Judith; Storey, Helen; Il Cheong, Hae; Gyung Kang, Hee; Park, Eujin; Hilbert, Pascale; Persikov, Anton; Torres-Fernandez, Carmen; Ars, Elisabet; Torra, Roser; Hertz, Jens Michael; Thomassen, Mads; Shagam, Lev; Wang, Dongmao; Wang, Yanyan; Flinter, Frances; Nagel, Mato

    2016-01-01

    Alport syndrome results from mutations in the COL4A5 (X-linked) or COL4A3/COL4A4 (recessive) genes. This study examined 754 previously- unpublished variants in these genes from individuals referred for genetic testing in 12 accredited diagnostic laboratories worldwide, in addition to all published COL4A5, COL4A3 and COL4A4 variants in the LOVD databases. It also determined genotype-phenotype correlations for variants where clinical data were available. Individuals were referred for genetic testing where Alport syndrome was suspected clinically or on biopsy (renal failure, hearing loss, retinopathy, lamellated glomerular basement membrane), variant pathogenicity was assessed using currently-accepted criteria, and variants were examined for gene location, and age at renal failure onset. Results were compared using Fisher's exact test (DNA Stata). Altogether 754 new DNA variants were identified, an increase of 25%, predominantly in people of European background. Of the 1168 COL4A5 variants, 504 (43%) were missense mutations, 273 (23%) splicing variants, 73 (6%) nonsense mutations, 169 (14%) short deletions and 76 (7%) complex or large deletions. Only 135 of the 432 Gly residues in the collagenous sequence were substituted (31%), which means that fewer than 10% of all possible variants have been identified. Both missense and nonsense mutations in COL4A5 were not randomly distributed but more common at the 70 CpG sequences (pAla substitutions were underrepresented in all three genes (p< 0.0001) probably because of an association with a milder phenotype. The average age at end-stage renal failure was the same for all mutations in COL4A5 (24.4 ±7.8 years), COL4A3 (23.3 ± 9.3) and COL4A4 (25.4 ± 10.3) (COL4A5 and COL4A3, p = 0.45; COL4A5 and COL4A4, p = 0.55; COL4A3 and COL4A4, p = 0.41). For COL4A5, renal failure occurred sooner with non-missense than missense variants (p<0.01). For the COL4A3 and COL4A4 genes, age at renal failure occurred sooner with two non-missense variants (p = 0.08, and p = 0.01 respectively). Thus DNA variant characteristics that predict age at renal failure appeared to be the same for all three Alport genes. Founder mutations (with the pathogenic variant in at least 5 apparently- unrelated individuals) were not necessarily associated with a milder phenotype. This study illustrates the benefits when routine diagnostic laboratories share and analyse their data.

  4. High Resolution Ultrasonography for Assessment of Renal Cysts in the PCK Rat Model of Autosomal Recessive Polycystic Kidney Disease

    Directory of Open Access Journals (Sweden)

    Sarika Kapoor

    2016-03-01

    Full Text Available Background/Aims: The PCK rat model of polycystic kidney disease is characterized by the progressive development of renal medullary cysts. Here, we evaluated the suitability of high resolution ultrasonography (HRU to assess the kidney and cyst volume in PCK rats, testing three different ultrasound image analysis methods, and correlating them with kidneys weights and histological examinations. Methods: After inducing anesthesia, PCK rats (n=18 were subjected to HRU to visualize the kidneys, to perform numeric and volumetric measurements of the kidney and any cysts observed, and to generate 3-dimensional images of the cysts within the kidney parenchyma. Results: HRU provided superior information in comparison to microscopic analysis of stained kidney sections. HRU-based kidney volumes correlated strongly with kidney weights (R2=0.809; PConclusion: HRU represents a useful diagnostic tool for kidney and cyst volume measurements in PCK rats. Sequential HRU examinations may be useful to study the effect of drugs on cyst growth without the need to euthanize experimental animals.

  5. Familial Clustering of Unexplained Transient Respiratory Distress in 12 Newborns from Three Unrelated Families Suggests an Autosomal-Recessive Inheritance

    OpenAIRE

    2007-01-01

    We report on 12 near-term babies from three families in which an unexplained transient respiratory distress was observed. No known risk factor was present in any family and no sequelae were recorded at follow-up. The most common causes of respiratory distress at birth are Neonatal Respiratory Distress Syndrome (NRD) and Transient Tachypnea of the Newborn (TTN), and their cumulative incidence is estimated to be about 2%. Genetic factors have been identified in NRD (surfactant genes) or suggest...

  6. Decreased catalytic activity and altered activation properties of PDE6C mutants associated with autosomal recessive achromatopsia

    DEFF Research Database (Denmark)

    Grau, Tanja; Artemyev, Nikolai O; Rosenberg, Thomas

    2011-01-01

    characterization of six missense mutations applying the baculovirus system to express recombinant mutant and wildtype chimeric PDE6C/PDE5 proteins in Sf9 insect cells. Purified proteins were analyzed using Western blotting, phosphodiesterase (PDE) activity measurements as well as inhibition assays by zaprinast...

  7. Research situation of amelogenesis imperfecta%遗传性釉质发育不全研究现状

    Institute of Scientific and Technical Information of China (English)

    王欣; 赵玉鸣

    2016-01-01

    遗传性釉质发育不全(amelogenesis imperfecta,AI)通常是指不伴有系统性疾病的一类单基因遗传病,乳牙、恒牙均可累及.目前已知的AI致病基因众多,且临床表型和基因型之间存在一定相关性.AI治疗计划的制定及预后评估与早期确诊息息相关.

  8. Disease: H01015 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available mental disorder CNNM4 [HSA:26504] [KO:K16302] Cone-rod dystrophy and amelogenesis...consisting of autosomal-recessive cone-rod dystrophy and amelogenesis imperfecta. Am J Hum Genet 84:266-73 (...2009) PMID:20706282 (descritpion) Jalili IK Cone-rod dystrophy and amelogenesis i...ogenesis imperfecta. It is caused mutations in the CNNM4 gene that encodes a putati...H01015 Jalili syndrome Jalili syndrome is a combination of recessively inherited cone-rod dystrophy and amel

  9. MiR-153 Regulates Amelogenesis by Targeting Endocytotic and Endosomal/lysosomal Pathways-Novel Insight into the Origins of Enamel Pathologies.

    Science.gov (United States)

    Yin, Kaifeng; Lin, Wenting; Guo, Jing; Sugiyama, Toshihiro; Snead, Malcolm L; Hacia, Joseph G; Paine, Michael L

    2017-03-13

    Amelogenesis imperfecta (AI) is group of inherited disorders resulting in enamel pathologies. The involvement of epigenetic regulation in the pathogenesis of AI is yet to be clarified due to a lack of knowledge about amelogenesis. Our previous genome-wide microRNA and mRNA transcriptome analyses suggest a key role for miR-153 in endosome/lysosome-related pathways during amelogenesis. Here we show that miR-153 is significantly downregulated in maturation ameloblasts compared with secretory ameloblasts. Within ameloblast-like cells, upregulation of miR-153 results in the downregulation of its predicted targets including Cltc, Lamp1, Clcn4 and Slc4a4, and a number of miRNAs implicated in endocytotic pathways. Luciferase reporter assays confirmed the predicted interactions between miR-153 and the 3'-UTRs of Cltc, Lamp1 (in a prior study), Clcn4 and Slc4a4. In an enamel protein intake assay, enamel cells transfected with miR-153 show a decreased ability to endocytose enamel proteins. Finally, microinjection of miR-153 in the region of mouse first mandibular molar at postnatal day 8 (PN8) induced AI-like pathologies when the enamel development reached maturity (PN12). In conclusion, miR-153 regulates maturation-stage amelogenesis by targeting key genes involved in the endocytotic and endosomal/lysosomal pathways, and disruption of miR-153 expression is a potential candidate etiologic factor contributing to the occurrence of AI.

  10. Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a Danish five-generation family with a novel FAM83H nonsense mutation

    DEFF Research Database (Denmark)

    Haubek, Dorte; Gjørup, Hans; Jensen, Lillian Gryesten

    2011-01-01

    BACKGROUND.  Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI) is a disease with severe dental manifestations. OBJECTIVES.  The aims were by means of a genome-wide linkage scan to search for the gene underlying the ADHCAI phenotype in a Danish five-generation family and to study...

  11. Amelogenesis imperfecta in two families with defined AMELX deletions in ARHGAP6.

    Directory of Open Access Journals (Sweden)

    Jan C-C Hu

    Full Text Available Amelogenesis imperfecta (AI is a group of inherited conditions featuring isolated enamel malformations. About 5% of AI cases show an X-linked pattern of inheritance, which are caused by mutations in AMELX. In humans there are two, non-allelic amelogenin genes: AMELX (Xp22.3 and AMELY (Yp11.2. About 90% of amelogenin expression is from AMELX, which is nested within intron 1 of the gene encoding Rho GTPase activating protein 6 (ARHGAP6. We recruited two AI families and determined that their disease-causing mutations were partial deletions in ARHGAP6 that completely deleted AMELX. Affected males in both families had a distinctive enamel phenotype resembling "snow-capped" teeth. The 96,240 bp deletion in family 1 was confined to intron 1 of ARHGAP6 (g.302534_398773del96240, but removed alternative ARHGAP6 promoters 1c and 1d. Analyses of developing teeth in mice showed that ARHGAP6 is not expressed from these promoters in ameloblasts. The 52,654 bp deletion in family 2 (g.363924_416577del52654insA removed ARHGAP6 promoter 1d and exon 2, precluding normal expression of ARHGAP6. The male proband of family 2 had slightly thinner enamel with greater surface roughness, but exhibited the same pattern of enamel malformations characteristic of males in family 1, which themselves showed minor variations in their enamel phenotypes. We conclude that the enamel defects in both families were caused by amelogenin insufficiency, that deletion of AMELX results in males with a characteristic snow-capped enamel phenotype, and failed ARHGAP6 expression did not appreciably alter the severity of enamel defects when AMELX was absent.

  12. Phenotype-genotype correlations in mouse models of amelogenesis imperfecta caused by Amelx and Enam mutations.

    Science.gov (United States)

    Coxon, Thomas Liam; Brook, Alan Henry; Barron, Martin John; Smith, Richard Nigel

    2012-01-01

    Mutations in human and in mouse orthologous genes Amelx and Enam result in a diverse range of enamel defects. In this study we aimed to investigate the phenotype-genotype correlation between the mutants and the wild-type controls in mouse models of amelogenesis imperfecta using novel measurement approaches. Ten hemi-mandibles and incisors were dissected from each group of Amelx(WT), Amelx(X/Y64H), Amelx(Y/Y64H), Amelx(Y64H/Y64H), and Enam(WT), Enam(Rgsc395) heterozygous and Enam(Rgsc395) homozygous mice. Their macro-morphology, colour and micro-topography were assessed using bespoke 2D and 3D image analysis systems and customized colour and whiteness algorithms. The novel methods identified significant differences (p ≤ 0.05) between the Amelx groups for mandible and incisor size and enamel colour and between the Enam groups for incisor size and enamel colour. The Amelx(WT) mice had the largest mandibles and incisors, followed in descending order of size by the Amelx(X/Y64H), Amelx(Y/Y64H) and Amelx(Y64H/Y64H) mice. Within the Enam groups the Enam(WT) incisors were largest and the Enam(Rgsc395) heterozygous mice were smallest. The effect on tooth morphology was also reflected by the severity of the enamel defects in the colour and whiteness assessment. Amelogenin affected mandible morphology and incisor enamel formation, while enamelin only affected incisors, supporting the multifunctional role of amelogenin. The enamelin mutation was associated with earlier forming enamel defects. The study supported the critical involvement of amelogenin and enamelin in enamel mineralization.

  13. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression

    Science.gov (United States)

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H.; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-01-01

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2f/f;Bmp4f/fameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling. PMID:27146352

  14. Abrogation of epithelial BMP2 and BMP4 causes Amelogenesis Imperfecta by reducing MMP20 and KLK4 expression.

    Science.gov (United States)

    Xie, Xiaohua; Liu, Chao; Zhang, Hua; Jani, Priyam H; Lu, Yongbo; Wang, Xiaofang; Zhang, Bin; Qin, Chunlin

    2016-05-05

    Amelogenesis Imperfecta (AI) can be caused by the deficiencies of enamel matrix proteins, molecules responsible for the transportation and secretion of enamel matrix components, and proteases processing enamel matrix proteins. In the present study, we discovered the double deletion of bone morphogenetic protein 2 (Bmp2) and bone morphogenetic protein 4 (Bmp4) in the dental epithelium by K14-cre resulted in hypoplastic enamel and reduced density in X-ray radiography as well as shortened enamel rods under scanning electron microscopy. Such enamel phenotype was consistent with the diagnosis of hypoplastic amelogenesis imperfecta. Histological and molecular analyses revealed that the removal of matrix proteins in the mutant enamel was drastically delayed, which was coincided with the greatly reduced expression of matrix metalloproteinase 20 (MMP20) and kallikrein 4 (KLK4). Although the expression of multiple enamel matrix proteins was down-regulated in the mutant ameloblasts, the cleavage of ameloblastin was drastically impaired. Therefore, we attributed the AI primarily to the reduction of MMP20 and KLK4. Further investigation found that BMP/Smad4 signaling pathway was down-regulated in the K14-cre;Bmp2(f/f);Bmp4(f/f)ameloblasts, suggesting that the reduced MMP20 and KLK4 expression may be due to the attenuated epithelial BMP/Smad4 signaling.

  15. Amelogenin signal peptide mutation: Correlation between mutations in the amelogenin gene (AMGX) and manifestations of X-linked amelogenesis imperfecta

    Energy Technology Data Exchange (ETDEWEB)

    Lagerstroem-Fermer, M.; Nilsson, M.; Pettersson, U. [Univ. of Uppsala (Sweden)] [and others

    1995-03-01

    Formation of tooth enamel is a poorly understood biological process. In this study the authors describe a 9-bp deletion in exon 2 of the amelogenin gene (AMGX) causing X-linked hypoplastic amelogenesis imperfecta, a disease characterized by defective enamel. The mutation results in the loss of 3 amino acids and exchange of 1 in the signal peptide of the amelogenin protein. This deletion in the signal peptide probably interferes with translocation of the amelogenin protein during synthesis, resulting in the thin enamel observed in affected members of the family. The authors compare this mutation to a previously reported mutation in the amelogenin gene that causes a different disease phenotype. The study illustrates that molecular analysis can help explain the various manifestations of a tooth disorder and thereby provide insights into the mechanisms of tooth enamel formation. 16 refs., 2 figs., 1 tab.

  16. Interdisciplinary Full Mouth Rehabilitation of a Patient with Amelogenesis Imperfecta: A Case Report with 8 Years Follow-up.

    Science.gov (United States)

    Sreedevi, S; Sanjeev, R; Ephraim, Rena; Joseph, Mathai

    2014-01-01

    This case report deals with the interdisciplinary approach of a 28-year-old lady with Amelogenesis imperfecta of the hypoplastic kind. The patient came with a chief illness of worn out teeth, unsatisfactory esthetics and severe sensitivity of teeth. Her family history revealed a related situation in her father's brother and her sister. On clinical assessment, the crowns of all teeth were worn out. The plan of the treatment was to protect as much tooth structure, restore the vertical dimension, and improve esthetics and masticatory function. The treatment procedures involved prosthodontic, endodontic, and periodontic interventions. After recording the vertical height, endodontic treatment and crown lengthening were performed with respect to the lower anteriors. The lost vertical height was regained in stages by insertion of full coverage crowns for all the teeth. The patient's esthetic and functional needs were met with systematic and sequential interdisciplinary treatment approach.

  17. Loss of epithelial FAM20A in mice causes amelogenesis imperfecta, tooth eruption delay and gingival overgrowth

    Science.gov (United States)

    Li, Li-Li; Liu, Pei-Hong; Xie, Xiao-Hua; Ma, Su; Liu, Chao; Chen, Li; Qin, Chun-Lin

    2016-01-01

    FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM20A in dental tissues and to assess the pathological changes when this molecule is specifically nullified in individual tissues. Recently, we generated mice with a Fam20A-floxed allele containing the beta-galactosidase reporter gene. We analysed FAM20A expression in dental tissues using X-Gal staining, immunohistochemistry and in situ hybridization, which showed that the ameloblasts in the mouse mandibular first molar began to express FAM20A at 1 day after birth, and the reduced enamel epithelium in erupting molars expressed a significant level of FAM20A. By breeding K14-Cre mice with Fam20Aflox/flox mice, we created K14-Cre;Fam20Aflox/flox (conditional knock out, cKO) mice, in which Fam20A was inactivated in the epithelium. We analysed the dental tissues of cKO mice using X-ray radiography, histology and immunohistochemistry. The molar enamel matrix in cKO mice was much thinner than normal and was often separated from the dentinoenamel junction. The Fam20A-deficient ameloblasts were non-polarized and disorganized and were detached from the enamel matrix. The enamel abnormality in cKO mice was consistent with the diagnosis of amelogenesis imperfecta. The levels of enamelin and matrix metalloproteinase 20 were lower in the ameloblasts and enamel of cKO mice than the normal mice. The cKO mice had remarkable delays in the eruption of molars and hyperplasia of the gingival epithelium. The findings emphasize the essential roles of FAM20A in the development of dental and oral tissues. PMID:27281036

  18. Loss of epithelial FAM20A in mice causes amelogenesis imperfecta, tooth eruption delay and gingival overgrowth.

    Science.gov (United States)

    Li, Li-Li; Liu, Pei-Hong; Xie, Xiao-Hua; Ma, Su; Liu, Chao; Chen, Li; Qin, Chun-Lin

    2016-06-30

    FAM20A has been studied to a very limited extent. Mutations in human FAM20A cause amelogenesis imperfecta, gingival fibromatosis and kidney problems. It would be desirable to systemically analyse the expression of FAM20A in dental tissues and to assess the pathological changes when this molecule is specifically nullified in individual tissues. Recently, we generated mice with a Fam20A-floxed allele containing the beta-galactosidase reporter gene. We analysed FAM20A expression in dental tissues using X-Gal staining, immunohistochemistry and in situ hybridization, which showed that the ameloblasts in the mouse mandibular first molar began to express FAM20A at 1 day after birth, and the reduced enamel epithelium in erupting molars expressed a significant level of FAM20A. By breeding K14-Cre mice with Fam20A(flox/flox) mice, we created K14-Cre;Fam20A(flox/flox) (conditional knock out, cKO) mice, in which Fam20A was inactivated in the epithelium. We analysed the dental tissues of cKO mice using X-ray radiography, histology and immunohistochemistry. The molar enamel matrix in cKO mice was much thinner than normal and was often separated from the dentinoenamel junction. The Fam20A-deficient ameloblasts were non-polarized and disorganized and were detached from the enamel matrix. The enamel abnormality in cKO mice was consistent with the diagnosis of amelogenesis imperfecta. The levels of enamelin and matrix metalloproteinase 20 were lower in the ameloblasts and enamel of cKO mice than the normal mice. The cKO mice had remarkable delays in the eruption of molars and hyperplasia of the gingival epithelium. The findings emphasize the essential roles of FAM20A in the development of dental and oral tissues.

  19. MiR-153 Regulates Amelogenesis by Targeting Endocytotic and Endosomal/lysosomal Pathways–Novel Insight into the Origins of Enamel Pathologies

    Science.gov (United States)

    Yin, Kaifeng; Lin, Wenting; Guo, Jing; Sugiyama, Toshihiro; Snead, Malcolm L.; Hacia, Joseph G.; Paine, Michael L.

    2017-01-01

    Amelogenesis imperfecta (AI) is group of inherited disorders resulting in enamel pathologies. The involvement of epigenetic regulation in the pathogenesis of AI is yet to be clarified due to a lack of knowledge about amelogenesis. Our previous genome-wide microRNA and mRNA transcriptome analyses suggest a key role for miR-153 in endosome/lysosome-related pathways during amelogenesis. Here we show that miR-153 is significantly downregulated in maturation ameloblasts compared with secretory ameloblasts. Within ameloblast-like cells, upregulation of miR-153 results in the downregulation of its predicted targets including Cltc, Lamp1, Clcn4 and Slc4a4, and a number of miRNAs implicated in endocytotic pathways. Luciferase reporter assays confirmed the predicted interactions between miR-153 and the 3′-UTRs of Cltc, Lamp1 (in a prior study), Clcn4 and Slc4a4. In an enamel protein intake assay, enamel cells transfected with miR-153 show a decreased ability to endocytose enamel proteins. Finally, microinjection of miR-153 in the region of mouse first mandibular molar at postnatal day 8 (PN8) induced AI-like pathologies when the enamel development reached maturity (PN12). In conclusion, miR-153 regulates maturation-stage amelogenesis by targeting key genes involved in the endocytotic and endosomal/lysosomal pathways, and disruption of miR-153 expression is a potential candidate etiologic factor contributing to the occurrence of AI. PMID:28287144

  20. Treatment of teeth in the esthetic zone in a patient with amelogenesis imperfecta using composite veneers and the clear matrix technique: A case report

    OpenAIRE

    Bogosavljević Aleksandar; Mišina Vanja; Jordačević Jovana; Abazović Milka; Dukić Smiljka; Ristić Ljubiša; Daković Dragana

    2016-01-01

    Introduction. Restorative dental treatment of patients with a generalized form of amelogenesis imperfecta (AI) remains a challenge even today. The treatment approach is multidisciplinary and includes action of several dental disciplines such as restorative, orthodontic, and prosthetic dental specialties. Case report. A 18-year-old female patent was referred to the Department of Restorative Dentistry and Periodontology at the Military Medical Academy of Belg...

  1. Amelogenesis Imperfecta and Early Restorative Crown Therapy: An Interview Study with Adolescents and Young Adults on Their Experiences

    Science.gov (United States)

    Wickström, Anette; Hasselblad, Tove; Dahllöf, Göran

    2016-01-01

    Patients with Amelogenesis imperfecta (AI) can present with rapid tooth loss or fractures of enamel as well as alterations in enamel thickness, color, and shape; factors that may compromise aesthetic appearance and masticatory function. The aim was to explore the experiences and perceptions of adolescents and young adults living with AI and receiving early prosthetic therapy. Seven patients with severe AI aged 16 to 23 years who underwent porcelain crown therapy participated in one-to-one individual interviews. The interviews followed a topic guide consisting of open-ended questions related to experiences of having AI. Transcripts from the interviews were analyzed using thematic analysis. The analysis process identified three main themes: Disturbances in daily life, Managing disturbances, and Normalization of daily life. These themes explain the experiences of patients living with enamel disturbances caused by AI and receiving early crown therapy. Experiences include severe pain and sensitivity problems, feelings of embarrassment, and dealing with dental staff that lack knowledge and understanding of their condition. The patients described ways to manage their disturbances and to reduce pain when eating or drinking, and strategies for meeting other people. After definitive treatment with porcelain crown therapy, they described feeling like a normal patient. In conclusion the results showed that adolescents and young adults describe a profound effect of AI on several aspects of their daily life. PMID:27359125

  2. Noninvasive and Multidisciplinary Approach to the Functional and Esthetic Rehabilitation of Amelogenesis Imperfecta: A Pediatric Case Report

    Directory of Open Access Journals (Sweden)

    Juliana Feltrin de Souza

    2014-01-01

    Full Text Available Case Report. An 8-year-old girl with amelogenesis imperfecta (AI reported unsatisfactory aesthetics, difficulty in mastication, and dental hypersensitivity. The intraoral examination observed mixed dentition, malocclusion in anteroposterior relationships, anterior open bite, and dental asymmetry. A hypoplastic form of AI was diagnosed in the permanent dentition. A multidisciplinary planning was performed and divided into preventive, orthopedic, and rehabilitation stages. Initially, preventive treatment was implemented, with fluoride varnish applications, in order to protect the fragile enamel and reduce the dental sensitivity. In the second stage, the patient received an interceptive orthopedic treatment to improve cross-relationship of the arches during six months. Finally, the rehabilitation treatment was executed to establish the vertical dimension. In the posterior teeth, indirect composite resin crowns were performed with minimally invasive dental preparation. Direct composite resin restorations were used to improve the appearance of anterior teeth. Follow-Up. The follow-up was carried out after 3, 6, 12, and 18 months. After 18 months of follow-up, The restoration of integrity, oral hygiene, and patient satisfaction were observed . Conclusion. Successful reduction of the dental hypersensitivity and improvement of the aesthetic and functional aspects as well as quality of life were observed.

  3. Ultrastructural and immunocytochemical characterization of ameloblast-enamel adhesion at maturation stage in amelogenesis in Macaca fuscata tooth germ.

    Science.gov (United States)

    Sawada, Takashi

    2015-12-01

    Maturation-stage ameloblasts are firmly bound to the tooth enamel by a basal lamina-like structure. The mechanism underlying this adhesion, however, remains to be fully clarified. The goal of this study was to investigate the mechanism underlying adhesion between the basal lamina-like structure and the enamel in monkey tooth germ. High-resolution immunogold labeling was performed to localize amelotin and laminin 332 at the interface between ameloblasts and tooth enamel. Minute, electron-dense strands were observed on the enamel side of the lamina densa, extending into the degrading enamel matrix to produce a well-developed fibrous layer (lamina fibroreticularis). In un-demineralized tissue sections, mineral crystals smaller than those in the bulk of the enamel were observed adhering to these strands where they protruded into the surface enamel. Immunogold particles reactive for amelotin were preferentially localized on these strands in the fibrous layer. On the other hand, those for laminin 332 were localized solely in the lamina densa; none were observed in the fibrous layer. These results suggest that the fibrous layer of the basal lamina-like structure is partly composed of amelotin molecules, and that these molecules facilitate ameloblast-enamel adhesion by promoting mineralization of the fibrous layer during the maturation stage of amelogenesis.

  4. Co-operative mineralization and protein self-assembly in amelogenesis: silica mineralization and assembly of recombinant amelogenins in vitro.

    Science.gov (United States)

    Fowler, Christabel E; Beniash, Elia; Yamakoshi, Yasuo; Simmer, James P; Margolis, Henry C

    2006-05-01

    An amorphous silica mineralization technique was used to produce inorganic/protein composites to elucidate the structure and mechanism of formation of amelogenin assemblies, which may play an important role in regulating enamel structure during the initial stages of amelogenesis. Full-length recombinant amelogenins from mouse (rM179) and pig (rP172) were investigated along with key degradation products (rM166 and native P148) lacking the hydrophilic C terminus found in parent molecules. The resulting products were examined using transmission electron microscopy and/or small-angle X-ray scattering. Using protein concentrations of 0.1-3 mg ml-1, large monodisperse spheres of remarkably similar mean diameters were observed using rM179 (124+/-4 nm) and rP172 (126+/-7 nm). These spheres also exhibited 'internal structure', comprising nearly spherical monodisperse particles of approximately 20 nm in diameter. In the presence of rM166, P148, and bovine serum albumin (control), large unstructured and randomly shaped particles (250-1000 nm) were observed. Without added protein, large dense spherical particles of silica (mean approximately 500 nm) lacking internal structure were produced. These findings demonstrate that full-length amelogenins have the ability to form higher-order structures, whereas amelogenins that lack the hydrophilic C terminus do not. The results also suggest that full-length amelogenin can guide the formation of organized mineralized structures through co-operative interactions between assembling protein and forming mineral.

  5. Amelogenesis Imperfecta and Early Restorative Crown Therapy: An Interview Study with Adolescents and Young Adults on Their Experiences.

    Directory of Open Access Journals (Sweden)

    Gunilla Pousette Lundgren

    Full Text Available Patients with Amelogenesis imperfecta (AI can present with rapid tooth loss or fractures of enamel as well as alterations in enamel thickness, color, and shape; factors that may compromise aesthetic appearance and masticatory function. The aim was to explore the experiences and perceptions of adolescents and young adults living with AI and receiving early prosthetic therapy. Seven patients with severe AI aged 16 to 23 years who underwent porcelain crown therapy participated in one-to-one individual interviews. The interviews followed a topic guide consisting of open-ended questions related to experiences of having AI. Transcripts from the interviews were analyzed using thematic analysis. The analysis process identified three main themes: Disturbances in daily life, Managing disturbances, and Normalization of daily life. These themes explain the experiences of patients living with enamel disturbances caused by AI and receiving early crown therapy. Experiences include severe pain and sensitivity problems, feelings of embarrassment, and dealing with dental staff that lack knowledge and understanding of their condition. The patients described ways to manage their disturbances and to reduce pain when eating or drinking, and strategies for meeting other people. After definitive treatment with porcelain crown therapy, they described feeling like a normal patient. In conclusion the results showed that adolescents and young adults describe a profound effect of AI on several aspects of their daily life.

  6. Full-mouth adhesive rehabilitation in a case of amelogenesis imperfecta: a 5-year follow-up case report.

    Science.gov (United States)

    Gerdolle, David; Mortier, Eric; Richard, Adeline; Vailati, Francesca

    2015-01-01

    Amelogenesis imperfecta (AI) is a hereditary disorder caused by mutations of genes primarily involved in the enamel formation. Several different types of AI have been identified, based on the phenotype and on the mode of inheritance. Regardless of the type, the dental treatment tends to be the same, favoring the complete removal of the compromised enamel late in the patient's life. With the new dentistry guidelines that orient clinicians towards minimal invasiveness, it should be mandatory to intercept patients affected by AI earlier, not only to protect the dentition from further degradation but also to help patients improve their self-esteem. This article examines the restorative dentistry performed on a 24-year-old Caucasian female suffering from the hypoplastic type of AI, using only adhesive procedures. Due to the complex needs of the patient, an interdisciplinary approach was followed, involving orthodontics, periodontics, and restorative dentistry. A full-mouth adhesive rehabilitation was achieved by means of direct composite restorations, veneer/onlays and facial/palatal veneers. No elective endodontic therapy was necessary for restorative purposes. The esthetics, mechanics, and biological success were achieved and maintained. The bond to the enamel did not show signs of degradation (eg, discoloration or infiltration) even after 5 years of function. This is encouraging as it shows that adhesive techniques may be a reliable approach even in the presence of a compromised enamel layer.

  7. Mapping of the locus for autosomal dominant amelogenesis imperfecta (AIH2) to a 4-Mb YAC contig on chromosome 4q11-q21

    Energy Technology Data Exchange (ETDEWEB)

    Kaerrman, C.; Holmgren, G.; Forsman, K. [Univ. Hospital, Umea (Sweden)]|[Univ. of Umea (Sweden)] [and others

    1997-01-15

    Amelogenesis imperfecta (Al) is a clinically and genetically heterogeneous group of inherited enamel defects. We recently mapped a locus for autosomal dominant local hypoplastic amelogenesis imperfecta (AIH2) to the long arm of chromosome 4. The disease gene was localized to a 17.6-cM region between the markers D4S392 and D4S395. The albumin gene (ALB), located in the same interval, was a candidate gene for autosomal dominant AI (ADAI) since albumin has a potential role in enamel maturation. Here we describe refined mapping of the AIH2 locus and the construction of marker maps by radiation hybrid mapping and yeast artificial chromosome (YAC)-based sequence tagged site-content mapping. A radiation hybrid map consisting of 11 microsatellite markers in the 5-cM interval between D4S409 and D4S1558 was constructed. Recombinant haplotypes in six Swedish ADAI families suggest that the disease gene is located in the interval between D4S2421 and ALB. ALB is therefore not likely to be the disease-causing gene. Affected members in all six families share the same allele haplotypes, indicating a common ancestral mutation in all families. The AIH2 critical region is less than 4 cM and spans a physical distance of approximately 4 Mb as judged from radiation hybrid maps. A YAC contig over the AIH2 critical region including several potential candidate genes was constructed. 35 refs., 4 figs., 1 tab.

  8. The genetics of amelogenesis imperfecta: a review of the literature Genética da amelogênese imperfeita: uma revisão da literatura

    Directory of Open Access Journals (Sweden)

    Maria Cristina Leme Godoy dos Santos

    2005-09-01

    Full Text Available A melogenesis imperfecta (AI is a group of inherited defects of dental enamel formation that show both clinical and genetic heterogeneity. Enamel findings in AI are highly variable, ranging from deficient enamel formation to defects in the mineral and protein content. Enamel formation requires the expression of multiple genes that transcribes matrix proteins and proteinases needed to control the complex process of crystal growth and mineralization. The AI phenotypes depend on the specific gene involved, the location and type of mutation, and the corresponding putative change at the protein level. Different inheritance patterns such as X-linked, autosomal dominant and autosomal recessive types have been reported. Mutations in the amelogenin, enamelin, and kallikrein-4 genes have been demonstrated to result in different types of AI and a number of other genes critical to enamel formation have been identified and proposed as candidates for AI. The aim of this article was to present an evaluation of the literature regarding role of proteins and proteinases important to enamel formation and mutation associated with AI.A melogênese imperfeita é um grupo de doenças hereditárias que causa defeito na formação esmalte dental e mostra heterogeneidade clínica e genética. O esmalte é afetado com alta variabilidade, desde deficiência na formação do esmalte até defeitos no conteúdo mineral e protéico. A formação do esmalte requer a expressão de múltiplos genes que transcrevem proteínas e proteinases importantes para controlar o complexo processo de crescimento dos cristais e mineralização. O fenótipo da AI depende do gene envolvido, sua localização e tipo de mutação, e a conseqüente alteração na proteína. Diferentes padrões hereditários com ligado ao X, autossômico dominante e autossômico recessivo já foram descritos. Mutações nos genes correspondentes da amelogenina, enamelina, e calicreína-4 demonstraram resultar em

  9. Autosomal-recessive posterior microphthalmos is caused by mutations in PRSS56, a gene encoding a trypsin-like serine protease

    DEFF Research Database (Denmark)

    Gal, Andreas; Rau, Isabella; El Matri, Leila

    2011-01-01

    amino acid long secreted trypsin-like serine peptidase. The c.1066dupC is likely to result in a functional null allele, whereas the two point mutations predict the replacement of evolutionary conserved and functionally important residues. Molecular modeling of the p.Trp309Ser mutant suggests that both...... refined the position of the disease locus (MCOP6) in an interval of 250 kb in chromosome 2q37.1 in two large Faroese families. We detected three different mutations in PRSS56. Patients of the Faroese families were either homozygous for c.926G>C (p.Trp309Ser) or compound heterozygous for c.926G>C and c.526......C>G (p.Arg176Gly), whereas a homozygous 1 bp duplication (c.1066dupC) was identified in five patients with arMCOP from a consanguineous Tunisian family. In one patient with MCOP from the Faroe Islands and in another one from Turkey, no PRSS56 mutation was detected, suggesting nonallelic...

  10. GPR179 is required for depolarizing bipolar cell function and is mutated in autosomal-recessive complete congenital stationary night blindness

    NARCIS (Netherlands)

    N.S. Peachey (Neal ); T.A. Ray (Thomas A.); R.J. Florijn (Ralph); L.B. Rowe (Lucy ); T. Sjoerdsma (Trijntje); S. Contreras-Alcantara (Susana); K. Baba (Kenkichi); G. Tosini (Gianluca); N. Pozdeyev (Nikita); P.M. Iuvone (P. Michael); P. Bojang Jr. (Pasano); J.N. Pearring (Jillian ); H.J. Simonsz (Huib); M.M. van Genderen (Maria); D.G. Birch (David ); E.I. Traboulsi (Elias); A. Dorfman (Allison); I. Lopez (Irma); H. Ren (Huanan); A.F.X. Goldberg (Andrew ); P.M. Nishina (Patsy); P. Lachapelle (Pierre); M.A. McCall (Maureen ); R.K. Koenekoop (Robert); A.A.B. Bergen (Arthur); M. Kamermans; R.G. Gregg (Ronald)

    2012-01-01

    textabstractComplete congenital stationary night blindness (cCSNB) is a clinically and genetically heterogeneous group of retinal disorders characterized by nonprogressive impairment of night vision, absence of the electroretinogram (ERG) b-wave, and variable degrees of involvement of other visual f

  11. Autosomal Recessive Hereditary Agammaglobulinemia%常染色体隐性遗传的无丙种球蛋白血症

    Institute of Scientific and Technical Information of China (English)

    王悦

    2005-01-01

    在原发性免疫缺陷病中,抗体介导的原发性B细胞缺陷的发生率占50%以上,其中X连锁无丙种球蛋白血症、选择性IgA缺陷、常见变异型免疫不全症等因其相对多见而被熟知.而常染色体隐性遗传的无丙种球蛋白血症也是能导致原发性B细胞缺陷的一类疾病,近10年来才在世界上引起重视并有病例报道.该文介绍了这类疾病的分类、病因、发病机制、诊断、治疗和预后等方面的特点,旨在呼吁儿科界关注此种疾病.

  12. Mutations in SLC33A1 cause a lethal autosomal-recessive disorder with congenital cataracts, hearing loss, and low serum copper and ceruloplasmin

    DEFF Research Database (Denmark)

    Huppke, Peter; Brendel, Cornelia; Kalscheuer, Vera

    2012-01-01

    , hearing loss, and severe developmental delay. Cerebral MRI showed pronounced cerebellar hypoplasia and hypomyelination. Homozygosity mapping was performed and displayed a region of commonality among three families at chromosome 3q25. Deep sequencing and conventional sequencing disclosed homozygous...

  13. ATP6V0A2 mutations present in two Mexican Mestizo children with an autosomal recessive cutis laxa syndrome type IIA

    Directory of Open Access Journals (Sweden)

    D. Bahena-Bahena

    2014-01-01

    Full Text Available Patients with ARCL-IIA harbor mutations in ATP6V0A2 that codes for an organelle proton pump. The ARCL-IIA syndrome characteristically presents a combined glycosylation defect affecting N-linked and O-linked glycosylations, differentiating it from other cutis laxa syndromes and classifying it as a Congenital Disorder of Glycosylation (ATP6V0A2-CDG. We studied two Mexican Mestizo patients with a clinical phenotype corresponding to an ARCL-IIA syndrome. Both patients presented abnormal transferrin (N-linked glycosylation but Patient 1 had a normal ApoCIII (O-linked glycosylation profile. Mutational screening of ATP6V0A2 using cDNA and genomic DNA revealed in Patient 1 a previously reported homozygous nonsense mutation c.187C>T (p.R63X associated with a novel clinical finding of a VSD. In Patient 2 we found a homozygous c.2293C>T (p.Q765X mutation that had been previously reported but found that it also altered RNA processing generating a novel transcript not previously identified (r.2176_2293del; p.F726Sfs*10. This is the first report to describe Mestizo patients with molecular diagnosis of ARCL-IIA/ATP6V0A2-CDG and to establish that their mutations are the first to be found in patients from different regions of the world and with different genetic backgrounds.

  14. CNTNAP2 and NRXN1 are mutated in autosomal-recessive Pitt-Hopkins-like mental retardation and determine the level of a common synaptic protein in Drosophila.

    NARCIS (Netherlands)

    Zweier, C.; Jong, E.K. de; Zweier, M.; Orrico, A.; Ousager, L.B.; Collins, A.L.; Bijlsma, E.K.; Oortveld, M.A.W.; Ekici, A.B.; Reis, A.; Schenck, A.; Rauch, A.

    2009-01-01

    Heterozygous copy-number variants and SNPs of CNTNAP2 and NRXN1, two distantly related members of the neurexin superfamily, have been repeatedly associated with a wide spectrum of neuropsychiatric disorders, such as developmental language disorders, autism spectrum disorders, epilepsy, and schizophr

  15. CNTNAP2 and NRXN1 are mutated in autosomal-recessive Pitt-Hopkins-like mental retardation and determine the level of a common synaptic protein in Drosophila

    DEFF Research Database (Denmark)

    Zweier, Christiane; de Jong, Eiko K; Zweier, Markus;

    2009-01-01

    Heterozygous copy-number variants and SNPs of CNTNAP2 and NRXN1, two distantly related members of the neurexin superfamily, have been repeatedly associated with a wide spectrum of neuropsychiatric disorders, such as developmental language disorders, autism spectrum disorders, epilepsy...... protein can reorganize synaptic morphology and induce increased density of active zones, the synaptic domains of neurotransmitter release. Moreover, both Nrx-I and Nrx-IV determine the level of the presynaptic active-zone protein bruchpilot, indicating a possible common molecular mechanism in Nrx......, and schizophrenia. We now identified homozygous and compound-heterozygous deletions and mutations via molecular karyotyping and mutational screening in CNTNAP2 and NRXN1 in four patients with severe mental retardation (MR) and variable features, such as autistic behavior, epilepsy, and breathing anomalies...

  16. CNTNAP2 and NRXN1 are mutated in autosomal-recessive Pitt-Hopkins-like mental retardation and determine the level of a common synaptic protein in Drosophila.

    Science.gov (United States)

    Zweier, Christiane; de Jong, Eiko K; Zweier, Markus; Orrico, Alfredo; Ousager, Lilian B; Collins, Amanda L; Bijlsma, Emilia K; Oortveld, Merel A W; Ekici, Arif B; Reis, André; Schenck, Annette; Rauch, Anita

    2009-11-01

    Heterozygous copy-number variants and SNPs of CNTNAP2 and NRXN1, two distantly related members of the neurexin superfamily, have been repeatedly associated with a wide spectrum of neuropsychiatric disorders, such as developmental language disorders, autism spectrum disorders, epilepsy, and schizophrenia. We now identified homozygous and compound-heterozygous deletions and mutations via molecular karyotyping and mutational screening in CNTNAP2 and NRXN1 in four patients with severe mental retardation (MR) and variable features, such as autistic behavior, epilepsy, and breathing anomalies, phenotypically overlapping with Pitt-Hopkins syndrome. With a frequency of at least 1% in our cohort of 179 patients, recessive defects in CNTNAP2 appear to significantly contribute to severe MR. Whereas the established synaptic role of NRXN1 suggests that synaptic defects contribute to the associated neuropsychiatric disorders and to severe MR as reported here, evidence for a synaptic role of the CNTNAP2-encoded protein CASPR2 has so far been lacking. Using Drosophila as a model, we now show that, as known for fly Nrx-I, the CASPR2 ortholog Nrx-IV might also localize to synapses. Overexpression of either protein can reorganize synaptic morphology and induce increased density of active zones, the synaptic domains of neurotransmitter release. Moreover, both Nrx-I and Nrx-IV determine the level of the presynaptic active-zone protein bruchpilot, indicating a possible common molecular mechanism in Nrx-I and Nrx-IV mutant conditions. We therefore propose that an analogous shared synaptic mechanism contributes to the similar clinical phenotypes resulting from defects in human NRXN1 and CNTNAP2.

  17. Mutations in DCPS and EDC3 in autosomal recessive intellectual disability indicate a crucial role for mRNA decapping in neurodevelopment.

    Science.gov (United States)

    Ahmed, Iltaf; Buchert, Rebecca; Zhou, Mi; Jiao, Xinfu; Mittal, Kirti; Sheikh, Taimoor I; Scheller, Ute; Vasli, Nasim; Rafiq, Muhammad Arshad; Brohi, M Qasim; Mikhailov, Anna; Ayaz, Muhammad; Bhatti, Attya; Sticht, Heinrich; Nasr, Tanveer; Carter, Melissa T; Uebe, Steffen; Reis, André; Ayub, Muhammad; John, Peter; Kiledjian, Megerditch; Vincent, John B; Jamra, Rami Abou

    2015-06-01

    There are two known mRNA degradation pathways, 3' to 5' and 5' to 3'. We identified likely pathogenic variants in two genes involved in these two pathways in individuals with intellectual disability. In a large family with multiple branches, we identified biallelic variants in DCPS in three affected individuals; a splice site variant (c.636+1G>A) that results in an in-frame insertion of 45 nucleotides and a missense variant (c.947C>T; p.Thr316Met). DCPS decaps the cap structure generated by 3' to 5' exonucleolytic degradation of mRNA. In vitro decapping assays showed an ablation of decapping function for both variants in DCPS. In another family, we identified a homozygous mutation (c.161T>C; p.Phe54Ser) in EDC3 in two affected children. EDC3 stimulates DCP2, which decaps mRNAs at the beginning of the 5' to 3' degradation pathway. In vitro decapping assays showed that altered EDC3 is unable to enhance DCP2 decapping at low concentrations and even inhibits DCP2 decapping at high concentration. We show that individuals with biallelic mutations in these genes of seemingly central functions are viable and that these possibly lead to impairment of neurological functions linking mRNA decapping to normal cognition. Our results further affirm an emerging theme linking aberrant mRNA metabolism to neurological defects.

  18. Identification of a novel homozygous mutation, TMPRSS3: c.535G>A, in a Tibetan family with autosomal recessive non-syndromic hearing loss.

    Directory of Open Access Journals (Sweden)

    Dongyan Fan

    Full Text Available Different ethnic groups have distinct mutation spectrums associated with inheritable deafness. In order to identify the mutations responsible for congenital hearing loss in the Tibetan population, mutation screening for 98 deafness-related genes by microarray and massively parallel sequencing of captured target exons was conducted in one Tibetan family with familiar hearing loss. A homozygous mutation, TMPRSS3: c.535G>A, was identified in two affected brothers. Both parents are heterozygotes and an unaffected sister carries wild type alleles. The same mutation was not detected in 101 control Tibetan individuals. This missense mutation results in an amino acid change (p.Ala179Thr at a highly conserved site in the scavenger receptor cysteine rich (SRCR domain of the TMPRSS3 protein, which is essential for protein-protein interactions. Thus, this mutation likely affects the interactions of this transmembrane protein with extracellular molecules. According to our bioinformatic analyses, the TMPRSS3: c.535G>A mutation might damage protein function and lead to hearing loss. These data suggest that the homozygous mutation TMPRSS3: c.535G>A causes prelingual hearing loss in this Tibetan family. This is the first TMPRSS3 mutation found in the Chinese Tibetan population.

  19. Exclusion of the GNAS locus in PHP-Ib patients with broad GNAS methylation changes: evidence for an autosomal recessive form of PHP-Ib?

    Science.gov (United States)

    Fernández-Rebollo, Eduardo; Pérez de Nanclares, Guiomar; Lecumberri, Beatriz; Turan, Serap; Anda, Emma; Pérez-Nanclares, Gustavo; Feig, Denice; Nik-Zainal, Serena; Bastepe, Murat; Jüppner, Harald

    2011-08-01

    Most patients with autosomal dominant pseudohypoparathyroidism type Ib (AD-PHP-Ib) carry maternally inherited microdeletions upstream of GNAS that are associated with loss of methylation restricted to GNAS exon A/B. Only few AD-PHP-Ib patients carry microdeletions within GNAS that are associated with loss of all maternal methylation imprints. These epigenetic changes are often indistinguishable from those observed in patients affected by an apparently sporadic PHP-Ib form that has not yet been defined genetically. We have now investigated six female patients affected by PHP-Ib (four unrelated and two sisters) with complete or almost complete loss of GNAS methylation, whose healthy children (11 in total) showed no epigenetic changes at this locus. Analysis of several microsatellite markers throughout the 20q13 region made it unlikely that PHP-Ib is caused in these patients by large deletions involving GNAS or by paternal uniparental isodisomy or heterodisomy of chromosome 20 (patUPD20). Microsatellite and single-nucleotide variation (SNV) data revealed that the two affected sisters share their maternally inherited GNAS alleles with unaffected relatives that lack evidence for abnormal GNAS methylation, thus excluding linkage to this locus. Consistent with these findings, healthy children of two unrelated sporadic PHP-Ib patients had inherited different maternal GNAS alleles, also arguing against linkage to this locus. Based on our data, it appears plausible that some forms of PHP-Ib are caused by homozygous or compound heterozygous mutation(s) in an unknown gene involved in establishing or maintaining GNAS methylation.

  20. Addressing key issues in the consanguinity-related risk of autosomal recessive disorders in consanguineous communities: lessons from a qualitative study of British Pakistanis.

    Science.gov (United States)

    Darr, A; Small, N; Ahmad, W I U; Atkin, K; Corry, P; Modell, B

    2016-01-01

    Currently, there is no consensus regarding services required to help families with consanguineous marriages manage their increased genetic reproductive risk. Genetic services for communities with a preference for consanguineous marriage in the UK remain patchy, often poor. Receiving two disparate explanations of the cause of recessive disorders (cousin marriage and recessive inheritance) leads to confusion among families. Further, the realisation that couples in non-consanguineous relationships have affected children leads to mistrust of professional advice. British Pakistani families at-risk for recessive disorders lack an understanding of recessive disorders and their inheritance. Such an understanding is empowering and can be shared within the extended family to enable informed choice. In a three-site qualitative study of British Pakistanis, we explored family and health professional perspectives on recessively inherited conditions. Our findings suggest, firstly, that family networks hold strong potential for cascading genetic information, making the adoption of a family-centred approach an efficient strategy for this community. However, this is dependent on provision of high-quality and timely information from health care providers. Secondly, families' experience was of ill-coordinated and time-starved services, with few having access to specialist provision from Regional Genetics Services; these perspectives were consistent with health professionals' views of services. Thirdly, we confirm previous findings that genetic information is difficult to communicate and comprehend, further complicated by the need to communicate the relationship between cousin marriage and recessive disorders. A communication tool we developed and piloted is described and offered as a useful resource for communicating complex genetic information.

  1. Complex morphological and molecular genetic examination of amelogenesis imperfecta: a case presentation of two Czech siblings with a non-syndrome form of the disease.

    Science.gov (United States)

    Kripnerova, Tereza; Krulisova, Veronika; Ptakova, Nikola; Macek, Milan; Dostalova, Tatjana

    2014-01-01

    Amelogenesis imperfecta (AI) is an overarching term for a group of rare inherited disorders of hard tooth tissues. It is characterized by various defects in proper enamel formation. AI is a severe disorder that affects both the aesthetics and function of the dentition, with affected teeth increasingly suffering from dental caries. Therefore, early diagnosis and lifelong stomatological interventions are important. Due to the complex nature of AI family history, stomatological, radiographic, and molecular genetic examinations should be part of the diagnostic portfolio. Additionally, we utilized new visualization methods for the assessment of teeth demineralization. We present a case report of two affected Czech sisters (6 and 8 years old) with clinically defined AI. These are the first Czech cases in which comprehensive clinical and genetic analysis had been carried out and reflect the complex clinical nature, positive treatment options, and limitations of candidate-gene molecular genetic testing.

  2. Whole-exome sequencing, without prior linkage, identifies a mutation in LAMB3 as a cause of dominant hypoplastic amelogenesis imperfecta.

    Science.gov (United States)

    Poulter, James A; El-Sayed, Walid; Shore, Roger C; Kirkham, Jennifer; Inglehearn, Chris F; Mighell, Alan J

    2014-01-01

    The conventional approach to identifying the defective gene in a family with an inherited disease is to find the disease locus through family studies. However, the rapid development and decreasing cost of next generation sequencing facilitates a more direct approach. Here, we report the identification of a frameshift mutation in LAMB3 as a cause of dominant hypoplastic amelogenesis imperfecta (AI). Whole-exome sequencing of three affected family members and subsequent filtering of shared variants, without prior genetic linkage, sufficed to identify the pathogenic variant. Simultaneous analysis of multiple family members confirms segregation, enhancing the power to filter the genetic variation found and leading to rapid identification of the pathogenic variant. LAMB3 encodes a subunit of Laminin-5, one of a family of basement membrane proteins with essential functions in cell growth, movement and adhesion. Homozygous LAMB3 mutations cause junctional epidermolysis bullosa (JEB) and enamel defects are seen in JEB cases. However, to our knowledge, this is the first report of dominant AI due to a LAMB3 mutation in the absence of JEB.

  3. Treatment of teeth in the esthetic zone in a patient with amelogenesis imperfecta using composite veneers and the clear matrix technique: A case report

    Directory of Open Access Journals (Sweden)

    Bogosavljević Aleksandar

    2016-01-01

    Full Text Available Introduction. Restorative dental treatment of patients with a generalized form of amelogenesis imperfecta (AI remains a challenge even today. The treatment approach is multidisciplinary and includes action of several dental disciplines such as restorative, orthodontic, and prosthetic dental specialties. Case report. A 18-year-old female patent was referred to the Department of Restorative Dentistry and Periodontology at the Military Medical Academy of Belgrade, Serbia. She was diagnosed with AI and formerly had been treated for a long period of time at the Department of Pediatric Dentistry and Orthodontics. Her primary concern upon arrival was discomfort and concern for the esthetic appearance of the anterior teeth. The treatment was done with the modified clear matrix technique used in composite veneer restoration of teeth in the esthetic zone. Conclusion. Because fixed prosthetic restoration with crowns, is the final treatment of AI patients it involves severe tooth structure loss. The clear matrix method which was done in this case allowed for greater comfort, functionality, simplicity, speed, greater economic efficiency and tooth structure preservation.

  4. Limited phenotypic variation of hypocalcified amelogenesis imperfecta in a Danish five-generation family with a novel FAM83H nonsense mutation.

    Science.gov (United States)

    Haubek, Dorte; Gjørup, Hans; Jensen, Lillian G; Juncker, Inger; Nyegaard, Mette; Børglum, Anders D; Poulsen, Sven; Hertz, Jens M

    2011-11-01

    BACKGROUND.  Autosomal dominant hypocalcified amelogenesis imperfecta (ADHCAI) is a disease with severe dental manifestations. OBJECTIVES.  The aims were by means of a genome-wide linkage scan to search for the gene underlying the ADHCAI phenotype in a Danish five-generation family and to study the phenotypic variation of the enamel in affected family members. RESULTS.  Significant linkage was found to a locus at chromosome 8q24.3 comprising the gene FAM83H identified to be responsible for ADHCAI in other families. Subsequent sequencing of FAM83H in affected family members revealed a novel nonsense mutation, p.Y302X. Limited phenotypic variation was found among affected family members with loss of translucency and discoloration of the enamel. Extensive posteruptive loss of enamel was found in all teeth of affected subjects. The tip of the cusps on the premolars and molars and a zone along the gingival margin seemed resistant to posteruptive loss of enamel. We have screened FAM83H in another five unrelated Danish patients with a phenotype of ADHCAI similar to that in the five-generation family, and identified a de novo FAM83H nonsense mutation, p.Q452X in one of these patients. CONCLUSION.  We have identified a FAM83H mutation in two of six unrelated families with ADHCAI and found limited phenotypic variation of the enamel in these patients.

  5. Improved protocol to purify untagged amelogenin - Application to murine amelogenin containing the equivalent P70→T point mutation observed in human amelogenesis imperfecta.

    Science.gov (United States)

    Buchko, Garry W; Shaw, Wendy J

    2015-01-01

    Amelogenin is the predominant extracellular protein responsible for converting carbonated hydroxyapatite into dental enamel, the hardest and most heavily mineralized tissue in vertebrates. Despite much effort, the precise mechanism by which amelogenin regulates enamel formation is not fully understood. To assist efforts aimed at understanding the biochemical mechanism of enamel formation, more facile protocols to purify recombinantly expressed amelogenin, ideally without any tag to assist affinity purification, are advantageous. Here we describe an improved method to purify milligram quantities of amelogenin that exploits its high solubility in 2% glacial acetic acid under conditions of low ionic strength. The method involves heating the frozen cell pellet for two 15min periods at ∼70°C with 2min of sonication in between, dialysis twice in 2% acetic acid (1:250 v/v), and reverse phase chromatography. A further improvement in yield is obtained by resuspending the frozen cell pellet in 6M guanidine hydrochloride in the first step. The acetic acid heating method is illustrated with a murine amelogenin containing the corresponding P70→T point mutation observed in an human amelogenin associated with amelogenesis imperfecta (P71T), while the guanidine hydrochloride heating method is illustrated with wild type murine amelogenin (M180). The self-assembly properties of P71T were probed by NMR chemical shift perturbation studies as a function of protein (0.1-1.8mM) and NaCl (0-367mM) concentration. Relative to similar studies with wild type murine amelogenin, P71T self-associates at lower protein or salt concentrations with the interactions initiated near the N-terminus.

  6. X-ray micro-analysis of the mineralization patterns in developing enamel in hamster tooth germs exposed to fluoride in vitro during the secretory phase of amelogenesis

    Energy Technology Data Exchange (ETDEWEB)

    Lyaruu, D.M.; Blijleven, N.; Hoeben-Schornagel, K.; Bronckers, A.L.; Woeltgens, J.H.

    1989-09-01

    The developing enamel from three-day-old hamster first maxillary (M1) molar tooth germs exposed to fluoride (F-) in vitro was analyzed for its mineral content by means of the energy-dispersive x-ray microanalysis technique. The aim of this study was to obtain semi-quantitative data on the F(-)-induced hypermineralization patterns in the enamel and to confirm that the increase in electron density observed in micrographs of F(-)-treated enamel is indeed due to an increase in mineral content in the fluorotic enamel. The tooth germs were explanted during the early stages of secretory amelogenesis and initially cultured for 24 hr in the presence of 10 ppm F- in the culture medium. The germs were then cultured for another 24 hr without F-. In order to compare the ultrastructural results directly with the microprobe data, we used the same specimens for both investigations. The net calcium counts (measurement minus background counts) in the analyses were used as a measure of the mineral content in the enamel. The aprismatic pre-exposure enamel, deposited in vivo before the onset of culture, was the most hypermineralized region in the fluorotic enamel, i.e., it contained the highest amount of calcium measured. The degree of the F(-)-induced hypermineralization gradually decreased (but was not abolished) in the more mature regions of the enamel. The unmineralized enamel matrix secreted during the initial F- treatment in vitro mineralized during the subsequent culture without F-. The calcium content in this enamel layer was in the same order of magnitude as that recorded for the newly deposited enamel in control tooth germs cultured without F-.

  7. Adaptor protein complex 2-mediated, clathrin-dependent endocytosis, and related gene activities, are a prominent feature during maturation stage amelogenesis.

    Science.gov (United States)

    Lacruz, Rodrigo S; Brookes, Steven J; Wen, Xin; Jimenez, Jaime M; Vikman, Susanna; Hu, Ping; White, Shane N; Lyngstadaas, S Petter; Okamoto, Curtis T; Smith, Charles E; Paine, Michael L

    2013-03-01

    Molecular events defining enamel matrix removal during amelogenesis are poorly understood. Early reports have suggested that adaptor proteins (AP) participate in ameloblast-mediated endocytosis. Enamel formation involves the secretory and maturation stages, with an increase in resorptive function during the latter. Here, using real-time PCR, we show that the expression of clathrin and adaptor protein subunits are upregulated in maturation stage rodent enamel organ cells. AP complex 2 (AP-2) is the most upregulated of the four distinct adaptor protein complexes. Immunolocalization confirms the presence of AP-2 and clathrin in ameloblasts, with strongest reactivity at the apical pole. These data suggest that the resorptive functions of enamel cells involve AP-2 mediated, clathrin-dependent endocytosis, thus implying the likelihood of specific membrane-bound receptor(s) of enamel matrix protein debris. The mRNA expression of other endocytosis-related gene products is also upregulated during maturation including: lysosomal-associated membrane protein 1 (Lamp1); cluster of differentiation 63 and 68 (Cd63 and Cd68); ATPase, H(+) transporting, lysosomal V0 subunit D2 (Atp6v0d2); ATPase, H(+) transporting, lysosomal V1 subunit B2 (Atp6v1b2); chloride channel, voltage-sensitive 7 (Clcn7); and cathepsin K (Ctsk). Immunohistologic data confirms the expression of a number of these proteins in maturation stage ameloblasts. The enamel of Cd63-null mice was also examined. Despite increased mRNA and protein expression in the enamel organ during maturation, the enamel of Cd63-null mice appeared normal. This may suggest inherent functional redundancies between Cd63 and related gene products, such as Lamp1 and Cd68. Ameloblast-like LS8 cells treated with the enamel matrix protein complex Emdogain showed upregulation of AP-2 and clathrin subunits, further supporting the existence of a membrane-bound receptor-regulated pathway for the endocytosis of enamel matrix proteins. These data

  8. Nano-scratch research of amelogenesis imperfecta teeth%釉质发育不全磨牙的微观磨损性能研究

    Institute of Scientific and Technical Information of China (English)

    李悦; 高姗姗; 岳虹池; 于海洋

    2012-01-01

    目的 对比研究釉质发育不全磨牙的微观摩擦磨损性能.方法 分别采用原子力显微镜(AFM)、能量色散X线光谱仪(EDX)对釉质发育不全牙及正常牙进行微观形貌观察和物质成分分析;通过纳米划痕技术并结合扫描电镜(SEM)对比分析其微观摩擦磨损性能上的差异.结果 AFM图显示釉质发育不全牙釉质比正常牙釉质连接疏松且可见有孔状结构,粗糙度大.EDX检测发现釉质发育不全牙釉质Ca、P含量较正常牙低,C含量较正常牙高.釉质发育不全牙釉质在同等载荷下较正常牙的摩擦系数大,破坏严重.结论 釉质发育不全牙与正常牙在微观结构、物质组成和微观摩擦磨损上均有较大差异.在临床上对釉质发育不全牙做修复时,应充分考虑这一因素.%Objective To study the differences between amelogenesis imperfecta (AI) teeth and normal human (NH) teeth in wear properties. Methods The ultrastructure of the human tooth enamel from adult patient diagnosed with AI was investigated using atomic force microscope (AFM) and compared with the surface of normal human tooth enamel. The composition of tooth enamel of AI teeth and normal human teeth were analyzed by energydispersive X-ray spec-troscopy (EDX). The properties of micro-friction and wear between AI teeth and normal human teeth were compared using nano-scratch technology and scanning electron microscope (SEM). Results The AI teeth were found porosity and the loosely packed hydroxyapatite was distributed randomly compared with normal human teeth. The amount of C was higher while the amount of Ca, P were lower in AI teeth than normal human teeth. The friction coefficient of both AI teeth and normal human teeth was increasing with the load increased and the friction coefficient of AI teeth was higher than normal human teeth with the same load. Meanwhile, the destruction of AI teeth was more severe than normal human teeth with the same load. Conclusion The AI

  9. Amelogenesis imperfecta with bilateral nephrocalcinosis

    OpenAIRE

    P Poornima; Katkade, Shashikant; Mohamed, Roshan Noor; Mallikarjuna, Rachappa

    2013-01-01

    A 12-year-old patient presented with a severe delay of eruption in permanent maxillary and mandibular incisors. On examination, there was over-retained primary teeth and delayed eruption of permanent teeth. Retained primary teeth showed light yellow discolouration whereas permanent teeth were distinct yellow with thin or little enamel. Subsequent imaging revealed all the premolars except maxillary left first premolar showed signs of intra-alveolar coronal resorption, nephrocalcinosis with bil...

  10. Amelogenesis imperfecta with bilateral nephrocalcinosis.

    Science.gov (United States)

    Poornima, P; Katkade, Shashikant; Mohamed, Roshan Noor; Mallikarjuna, Rachappa

    2013-05-24

    A 12-year-old patient presented with a severe delay of eruption in permanent maxillary and mandibular incisors. On examination, there was over-retained primary teeth and delayed eruption of permanent teeth. Retained primary teeth showed light yellow discolouration whereas permanent teeth were distinct yellow with thin or little enamel. Subsequent imaging revealed all the premolars except maxillary left first premolar showed signs of intra-alveolar coronal resorption, nephrocalcinosis with bilateral multiple calculi and small papillary tip calcifications, marked increase in alkaline phosphatase. Subsequent dental treatment for restoring the functional and aesthetic requirement followed by appropriate treatment for renal problem was undertaken.

  11. Case Report: Whole exome sequencing reveals a novel frameshift deletion mutation p.G2254fs in COL7A1 associated with autosomal recessive dystrophic epidermolysis bullosa [version 2; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Shamsudheen Karuthedath Vellarikkal

    2016-07-01

    Full Text Available Dystrophic epidermolysis bullosa simplex (DEB is a phenotypically diverse inherited skin fragility disorder. It is majorly manifested by appearance of epidermal bullae upon friction caused either by physical or environmental trauma. The phenotypic manifestations also include appearance of milia, scarring all over the body and nail dystrophy. DEB can be inherited in a recessive or dominant form and the recessive form of DEB (RDEB is more severe. In the present study, we identify a novel p.G2254fs mutation in COL7A1 gene causing a sporadic case of RDEB by whole exome sequencing (WES. Apart from adding a novel frameshift Collagen VII mutation to the repertoire of known mutations reported in the disease, to the best of our knowledge, this is the first report of a genetically characterized case of DEB from India.

  12. Case Report: Whole exome sequencing reveals a novel frameshift deletion mutation p.G2254fs in COL7A1 associated with autosomal recessive dystrophic epidermolysis bullosa [version 1; referees: 2 approved, 1 approved with reservations

    Directory of Open Access Journals (Sweden)

    Shamsudheen Karuthedath Vellarikkal

    2016-05-01

    Full Text Available Dystrophic epidermolysis bullosa simplex (DEB is a phenotypically diverse inherited skin fragility disorder. It is majorly manifested by appearance of epidermal bullae upon friction caused either by physical or environmental trauma. The phenotypic manifestations also include appearance of milia, scarring all over the body and nail dystrophy. DEB can be inherited in a recessive or dominant form and the recessive form of DEB (RDEB is more severe. In the present study, we identify a novel p.G2254fs mutation in COL7A1 gene causing a sporadic case of RDEB by whole exome sequencing (WES. Apart from adding a novel frameshift Collagen VII mutation to the repertoire of known mutations reported in the disease, to the best of our knowledge, this is the first report of a genetically characterized case of DEB from India.

  13. Molecular Basis of Human Enamel Defects

    Directory of Open Access Journals (Sweden)

    Chatzopoulos Georgios

    2014-03-01

    Full Text Available During eruption of teeth in the oral cavity, the effect of gene variations and environmental factors can result in morphological and structural changes in teeth. Amelogenesis imperfecta is a failure which is detected on the enamel of the teeth and clinical picture varies by the severity and type of the disease. Classification of the types of amelogenesis imperfecta is determined by histological, genetic, clinical and radiographic criteria. Specifically, there are 4 types of amelogenesis imperfecta (according to Witkop: hypoplastic form, hypo-maturation form, hypo-calcified form, and hypo-maturation/hypoplasia form with taurodontism and 14 subcategories. The diagnosis and classification of amelogenesis imperfecta has traditionally been based on clinical presentation or phenotype and the inheritance pattern. Several genes can be mutated and cause the disease. Millions of genes, possibly more than 10,000 genes produce proteins that regulate synthesis of enamel. Some of the genes and gene products that are likely associated with amelogenesis imperfecta are: amelogenin (AMELX, AMELY genes, ameloblastin (AMBN gene, enamelin (ENAM gene, enamelysin (MMP20 gene, kalikryn 4 (KLK 4 gene, tuftelins (Tuftelin gene, FAM83H (FAM83H gene and WDR72 (WDR72 gene. Particular attention should be given by the dentist in recognition and correlation of phenotypes with genotypes, in order to diagnose quickly and accurately such a possible disease and to prevent or treat it easily and quickly. Modern dentistry should restore these lesions in order to guarantee aesthetics and functionality, usually in collaboration with a group of dentists.

  14. Bcl-2 expression during amelogenesis in mouse molars%Bcl-2在成釉细胞分化、分泌过程中的表达研究

    Institute of Scientific and Technical Information of China (English)

    于西佼; 唐开亮; 杜毅; 李纾

    2012-01-01

    目的:检测凋亡调控抑制蛋白Bcl-2在成釉细胞分化、分泌过程中的表达,观察细胞超微结构的变化,探讨Bcl-2和细胞凋亡在该过程的可能作用.方法:制备出生后2、5、7、9、14 d不同发育阶段的BALB/C小鼠下颌第一磨牙牙胚标本,采用原位末端标记法(TUNEL法)和PV免疫组织化学技术观察成釉细胞分化、分泌和釉质发育完成各阶段细胞凋亡以及Bcl-2的表达情况;透射电镜观察细胞超微结构的变化.结果:出生后第2~5天,小鼠下颌第一磨牙成釉细胞处于分化期,超微结构可见胞浆内有高尔基复合体和线粒体,并有细胞增生的核分裂;免疫组化结果显示Bcl-2阳性表达,TUNEL检测结果发现部分细胞胞核阳性表达,提示细胞凋亡的存在;出生后第7天,成釉细胞已开始分泌,可见新形成的釉质,胞核远基底排列,胞核附近可见大量线粒体,胞质内可见大量高尔基复合体和粗面内质网,胞浆呈Bcl-2强阳性表达,TUNEL检测结果发现少量细胞胞核阳性表达;出生后14 d,釉质发育完成,成釉细胞变短,间隙变大,细胞器数量减少,核膜逐渐不清,核糖体脱颗粒水肿,呈现凋亡征象,胞浆未见Bcl-2阳性表达.结论:细胞凋亡在釉质发育的各期皆有表达,Bcl-2作为凋亡抑制基因可能参与了成釉细胞的分化、分泌的调控.%AIM: To observe Bcl-2 expresion during amelogenesis in developing mouse molars. METH- ODS : First molar germs of postnatal 2 - 14 d BALB/C mice were extracted. The morphology and distribution of amelo-blasts in the tooth germ were examined by light and transmission electron microscopy. PV two-step immunohistochemi-cal method was used to detect the expression of Bcl-2 protein. Apoptosis was identified by the terminal deoxy-transfer-ase (TdT)-mediated dUTP-biotin nick end labeling (TUNEL) method. RESULTS: Bcl-2 positive cells was detected in the proliferating pre-ameloblasts and secretory stage ameloblasts

  15. Ameloblasts express type I collagen during amelogenesis.

    Science.gov (United States)

    Assaraf-Weill, N; Gasse, B; Silvent, J; Bardet, C; Sire, J Y; Davit-Béal, T

    2014-05-01

    Enamel and enameloid, the highly mineralized tooth-covering tissues in living vertebrates, are different in their matrix composition. Enamel, a unique product of ameloblasts, principally contains enamel matrix proteins (EMPs), while enameloid possesses collagen fibrils and probably receives contributions from both odontoblasts and ameloblasts. Here we focused on type I collagen (COL1A1) and amelogenin (AMEL) gene expression during enameloid and enamel formation throughout ontogeny in the caudate amphibian, Pleurodeles waltl. In this model, pre-metamorphic teeth possess enameloid and enamel, while post-metamorphic teeth possess enamel only. In first-generation teeth, qPCR and in situ hybridization (ISH) on sections revealed that ameloblasts weakly expressed AMEL during late-stage enameloid formation, while expression strongly increased during enamel deposition. Using ISH, we identified COL1A1 transcripts in ameloblasts and odontoblasts during enameloid formation. COL1A1 expression in ameloblasts gradually decreased and was no longer detected after metamorphosis. The transition from enameloid-rich to enamel-rich teeth could be related to a switch in ameloblast activity from COL1A1 to AMEL synthesis. P. waltl therefore appears to be an appropriate animal model for the study of the processes involved during enameloid-to-enamel transition, especially because similar events probably occurred in various lineages during vertebrate evolution.

  16. Disease: H00269 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00269 Primary microcephaly (MCPH) Autosomal recessive primary microcephaly (MCPH) ...t brain growth. Trends Mol Med 12:358-66 (2006) PMID:15806441 Woods CG, Bond J, Enard W Autosomal recessive

  17. EST Table: BY921544 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available ar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) ... similar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) isoform 1 [Tribolium castaneum] FS929848 ovS0 ...

  18. EST Table: DC540266 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available ar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) ... similar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) isoform 1 [Tribolium castaneum] FS929848 dpe- ...

  19. EST Table: FS929848 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available DICTED: similar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterole...1| PREDICTED: similar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) isoform 1 [Tribolium castaneum] FS929848 fwgP ...

  20. EST Table: FS936166 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available ar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) ... similar to Low density lipoprotein receptor adapter protein 1 (Autosomal recessive hypercholesterolemia protein) isoform 1 [Tribolium castaneum] FS929848 fwgP ...

  1. Disease: H00667 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00667 Woolly hair, including: Autosomal-dominant woolly hair (ADWH); Autosomal-rec...essive woolly hair (ARWH); Autosomal-recessive woolly hair with or without hypotrichosis Woolly hair (WH) is...autosomal dominant and autosomal recessive manner. Autosomal recessive woolly hai..., Wajid M, Petukhova L, Kurban M, Christiano AM Autosomal-dominant woolly hair re

  2. 常染色体隐性遗传早发性帕金森病1个家系临床特征及parkin基因突变分析%The clinical characteristics and mutation analysis of parkin gene in a family with autosomal recessive early-onset parkinsonism

    Institute of Scientific and Technical Information of China (English)

    柳四新; 郭纪锋; 唐北沙; 李静; 严新翔

    2008-01-01

    目的 探讨1个常染色体隐性遗传早发性帕金森病(autosornal recessive early-onset parkinson-ism,AREP)家系的临床特征及parkin基因突变情况.方法 对1个AREP家系2例患者的临床资料进行回顾性分析,同时应用DNA直接测序、限制性内切酶酶切、荧光半定量PCR等技术方法进行parkin基因的突变分析.结果 该家系共2例患者,发病年龄轻,分别为22岁和23岁;病情进展相对缓慢,症状有波动,呈晨轻暮重,腱反射活跃;对小剂量多巴制剂反应良好.基因突变发现该家系存在parkin基因的复合杂合突变(第7号外显子杂合的G859T和第4外显子杂合缺失突变),其中G859T为新报道的点突变.结论 我国的AREP家系有帕金森病的一般临床表现,又有其独特的临床特征,存在parkin基因的突变.

  3. Heimler Syndrome Is Caused by Hypomorphic Mutations in the Peroxisome-Biogenesis Genes PEX1 and PEX6

    Science.gov (United States)

    Ratbi, Ilham; Falkenberg, Kim D.; Sommen, Manou; Al-Sheqaih, Nada; Guaoua, Soukaina; Vandeweyer, Geert; Urquhart, Jill E.; Chandler, Kate E.; Williams, Simon G.; Roberts, Neil A.; El Alloussi, Mustapha; Black, Graeme C.; Ferdinandusse, Sacha; Ramdi, Hind; Heimler, Audrey; Fryer, Alan; Lynch, Sally-Ann; Cooper, Nicola; Ong, Kai Ren; Smith, Claire E.L.; Inglehearn, Christopher F.; Mighell, Alan J.; Elcock, Claire; Poulter, James A.; Tischkowitz, Marc; Davies, Sally J.; Sefiani, Abdelaziz; Mironov, Aleksandr A.; Newman, William G.; Waterham, Hans R.; Van Camp, Guy

    2015-01-01

    Heimler syndrome (HS) is a rare recessive disorder characterized by sensorineural hearing loss (SNHL), amelogenesis imperfecta, nail abnormalities, and occasional or late-onset retinal pigmentation. We ascertained eight families affected by HS and, by using a whole-exome sequencing approach, identified biallelic mutations in PEX1 or PEX6 in six of them. Loss-of-function mutations in both genes are known causes of a spectrum of autosomal-recessive peroxisome-biogenesis disorders (PBDs), including Zellweger syndrome. PBDs are characterized by leukodystrophy, hypotonia, SNHL, retinopathy, and skeletal, craniofacial, and liver abnormalities. We demonstrate that each HS-affected family has at least one hypomorphic allele that results in extremely mild peroxisomal dysfunction. Although individuals with HS share some subtle clinical features found in PBDs, the diagnosis was not suggested by routine blood and skin fibroblast analyses used to detect PBDs. In conclusion, our findings define HS as a mild PBD, expanding the pleiotropy of mutations in PEX1 and PEX6. PMID:26387595

  4. NCBI nr-aa BLAST: CBRC-CJAC-01-1207 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-CJAC-01-1207 ref|NP_733842.2| polyductin isoform 2 [Homo sapiens] emb|CAH73868.1| polycystic... kidney and hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAH72782.1| polycystic ...kidney and hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI16677.1| polycystic kidney and hepa...tic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI20325.1| polycystic kid

  5. NCBI nr-aa BLAST: CBRC-FCAT-01-1153 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FCAT-01-1153 ref|NP_733842.2| polyductin isoform 2 [Homo sapiens] emb|CAH73868.1| polycystic... kidney and hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAH72782.1| polycystic ...kidney and hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI16677.1| polycystic kidney and hepa...tic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI20325.1| polycystic kid

  6. Disease: H01170 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H01170 Autosomal recessive spastic ataxia of Charlevoix-Saguenay (ARSACS) Autosomal recessive spastic ataxia... of Charlevoix-Saguenay (ARSACS) is a distinct form of hereditary early-onset spastic ataxia...Fayeche G, Hentati F Autosomal recessive spastic ataxia of Charlevoix-Saguenay: an overview. Parkinsonism Re...lli FM, Benavente I, Modrego P, Tintore M, Berciano J Is the ataxia of Charlevoix-Saguenay a developmental d...n and Purkinje cell loss in autosomal recessive spastic ataxia of Charlevoix-Sagu

  7. Congenital adrenal hyperplasia with localized aggressive periodontitis and amelogenesis imperfecta.

    Science.gov (United States)

    Ajlan, Sumaiah Abdulbaqi

    2015-11-01

    Congenital adrenal hyperplasia (CAH) is an inherited medical condition that implies defects in steroid biosynthesis. The dental findings of a female patient with CAH are reported. The patient suffered from severe periodontal tissue destruction, obvious enamel defects, as well as some occlusal problems. The management approach is presented and the possibility of interrelation of her dental findings with her medical condition is discussed.

  8. Ectopic expression of dentin sialoprotein during amelogenesis hardens bulk enamel.

    Science.gov (United States)

    White, Shane N; Paine, Michael L; Ngan, Amanda Y W; Miklus, Vetea G; Luo, Wen; Wang, HongJun; Snead, Malcolm L

    2007-02-23

    Dentin sialophosphpoprotein (Dspp) is transiently expressed in the early stage of secretory ameloblasts. The secretion of ameloblast-derived Dspp is short-lived, correlates to the establishment of the dentinoenamel junction (DEJ), and is consistent with Dspp having a role in producing the specialized first-formed harder enamel adjacent to the DEJ. Crack diffusion by branching and dissipation within this specialized first-formed enamel close to the DEJ prevents catastrophic interfacial damage and tooth failure. Once Dspp is secreted, it is subjected to proteolytic cleavage that results in two distinct proteins referred to as dentin sialoprotein (Dsp) and dentin phosphoprotein (Dpp). The purpose of this study was to investigate the biological and mechanical contribution of Dsp and Dpp to enamel formation. Transgenic mice were engineered to overexpress either Dsp or Dpp in their enamel organs. The mechanical properties (hardness and toughness) of the mature enamel of transgenic mice were compared with genetically matched and age-matched nontransgenic animals. Dsp and Dpp contributions to enamel formation greatly differed. The inclusion of Dsp in bulk enamel significantly and uniformly increased enamel hardness (20%), whereas the inclusion of Dpp weakened the bulk enamel. Thus, Dsp appears to make a unique contribution to the physical properties of the DEJ. Dsp transgenic animals have been engineered with superior enamel mechanical properties.

  9. Amelogenins as potential buffers during secretory-stage amelogenesis

    NARCIS (Netherlands)

    Guo, J.; Lyaruu, D.M.; Takano, Y.; Gibson, C.W.; Denbesten, P.K.; Bronckers, A.L.

    2015-01-01

    Amelogenins are the most abundant protein species in forming dental enamel, taken to regulate crystal shape and crystal growth. Unprotonated amelogenins can bind protons, suggesting that amelogenins could regulate the pH in enamel in situ. We hypothesized that without amelogenins the enamel would ac

  10. Amelogenins as potential buffers during secretory-stage amelogenesis.

    Science.gov (United States)

    Guo, J; Lyaruu, D M; Takano, Y; Gibson, C W; DenBesten, P K; Bronckers, A L J J

    2015-03-01

    Amelogenins are the most abundant protein species in forming dental enamel, taken to regulate crystal shape and crystal growth. Unprotonated amelogenins can bind protons, suggesting that amelogenins could regulate the pH in enamel in situ. We hypothesized that without amelogenins the enamel would acidify unless ameloblasts were buffered by alternative ways. To investigate this, we measured the mineral and chloride content in incisor enamel of amelogenin-knockout (AmelX(-/-)) mice and determined the pH of enamel by staining with methyl-red. Ameloblasts were immunostained for anion exchanger-2 (Ae2), a transmembrane pH regulator sensitive for acid that secretes bicarbonate in exchange for chloride. The enamel of AmelX(-/-) mice was 10-fold thinner, mineralized in the secretory stage 1.8-fold more than wild-type enamel and containing less chloride (suggesting more bicarbonate secretion). Enamel of AmelX(-/-) mice stained with methyl-red contained no acidic bands in the maturation stage as seen in wild-type enamel. Secretory ameloblasts of AmelX(-/-) mice, but not wild-type mice, were immunopositive for Ae2, and stained more intensely in the maturation stage compared with wild-type mice. Exposure of AmelX(-/-) mice to fluoride enhanced the mineral content in the secretory stage, lowered chloride, and intensified Ae2 immunostaining in the enamel organ in comparison with non-fluorotic mutant teeth. The results suggest that unprotonated amelogenins may regulate the pH of forming enamel in situ. Without amelogenins, Ae2 could compensate for the pH drop associated with crystal formation.

  11. Crown lengthening procedure in the management of amelogenesis imperfecta

    OpenAIRE

    2015-01-01

    Full mouth rehabilitation includes a promising treatment planning and execution thus fulfilling esthetic, occlusal, and functional parameters maintaining the harmony of the stomatognathic system. Crown lengthening procedures have become an integral component of the esthetic armamentarium and are utilized with increasing frequency to enhance the appearance of restorations placed in the esthetic zone. Crown lengthening plays a role to create healthy relationship of the gingiva and bone levels s...

  12. Gclust Server: 22367 [Gclust Server

    Lifescience Database Archive (English)

    Full Text Available f two yeast homologs (with Sdo1p/Ylr022cp) of the human protein SBDS responsible for autosomal recessive Shwachman-Bodian-Diamond...m, one of two yeast homologs (with Sdo1p/Ylr022cp) of the human protein SBDS responsible for autosomal recessive Shwachman-Bodian-Dia...mond Syndrome, also conserved in Archaea Number of Seque

  13. Disease: H00557 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00557 Cutis laxa, including: Autosomal dominant cutis laxa (ADCL); Autosomal reces...sive cutis laxa I (ARCL1); Autosomal recessive cutis laxa II (ARCL2); X-linked recessive cutis laxa (XRCL); ...d M, Lefeber DJ, Wevers RA Autosomal recessive cutis laxa syndrome revisited. Eur J Hum Genet 17:1099-110 (2

  14. FAM20A mutations can cause enamel-renal syndrome (ERS.

    Directory of Open Access Journals (Sweden)

    Shih-Kai Wang

    Full Text Available Enamel-renal syndrome (ERS is an autosomal recessive disorder characterized by severe enamel hypoplasia, failed tooth eruption, intrapulpal calcifications, enlarged gingiva, and nephrocalcinosis. Recently, mutations in FAM20A were reported to cause amelogenesis imperfecta and gingival fibromatosis syndrome (AIGFS, which closely resembles ERS except for the renal calcifications. We characterized three families with AIGFS and identified, in each case, recessive FAM20A mutations: family 1 (c.992G>A; g.63853G>A; p.Gly331Asp, family 2 (c.720-2A>G; g.62232A>G; p.Gln241_Arg271del, and family 3 (c.406C>T; g.50213C>T; p.Arg136* and c.1432C>T; g.68284C>T; p.Arg478*. Significantly, a kidney ultrasound of the family 2 proband revealed nephrocalcinosis, revising the diagnosis from AIGFS to ERS. By characterizing teeth extracted from the family 3 proband, we demonstrated that FAM20A(-/- molars lacked true enamel, showed extensive crown and root resorption, hypercementosis, and partial replacement of resorbed mineral with bone or coalesced mineral spheres. Supported by the observation of severe ectopic calcifications in the kidneys of Fam20a null mice, we conclude that FAM20A, which has a kinase homology domain and localizes to the Golgi, is a putative Golgi kinase that plays a significant role in the regulation of biomineralization processes, and that mutations in FAM20A cause both AIGFS and ERS.

  15. Transcription factor FoxO1 is essential for enamel biomineralization.

    Directory of Open Access Journals (Sweden)

    Ross A Poché

    Full Text Available The Transforming growth factor β (Tgf-β pathway, by signaling via the activation of Smad transcription factors, induces the expression of many diverse downstream target genes thereby regulating a vast array of cellular events essential for proper development and homeostasis. In order for a specific cell type to properly interpret the Tgf-β signal and elicit a specific cellular response, cell-specific transcriptional co-factors often cooperate with the Smads to activate a discrete set of genes in the appropriate temporal and spatial manner. Here, via a conditional knockout approach, we show that mice mutant for Forkhead Box O transcription factor FoxO1 exhibit an enamel hypomaturation defect which phenocopies that of the Smad3 mutant mice. Furthermore, we determined that both the FoxO1 and Smad3 mutant teeth exhibit changes in the expression of similar cohort of genes encoding enamel matrix proteins required for proper enamel development. These data raise the possibility that FoxO1 and Smad3 act in concert to regulate a common repertoire of genes necessary for complete enamel maturation. This study is the first to define an essential role for the FoxO family of transcription factors in tooth development and provides a new molecular entry point which will allow researchers to delineate novel genetic pathways regulating the process of biomineralization which may also have significance for studies of human tooth diseases such as amelogenesis imperfecta.

  16. NCBI nr-aa BLAST: CBRC-CJAC-01-1207 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available HD1_HUMAN Polycystic kidney and hepatic disease 1 precursor (Fibrocystin) (Polyductin) (Tigmin) gb|AAL74290.1| polycystic... kidney and hepatic disease 1 [Homo sapiens] emb|CAH73867.1| polycystic kidney and hepatic dise...ase 1 (autosomal recessive) [Homo sapiens] emb|CAH72781.1| polycystic kidney and ...hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI16676.1| polycystic kidney and hepatic disease... 1 (autosomal recessive) [Homo sapiens] emb|CAI20324.1| polycystic kidney and hepatic disease 1 (autosomal r

  17. NCBI nr-aa BLAST: CBRC-FCAT-01-1153 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available HD1_HUMAN Polycystic kidney and hepatic disease 1 precursor (Fibrocystin) (Polyductin) (Tigmin) gb|AAL74290.1| polycystic... kidney and hepatic disease 1 [Homo sapiens] emb|CAH73867.1| polycystic kidney and hepatic dise...ase 1 (autosomal recessive) [Homo sapiens] emb|CAH72781.1| polycystic kidney and ...hepatic disease 1 (autosomal recessive) [Homo sapiens] emb|CAI16676.1| polycystic kidney and hepatic disease... 1 (autosomal recessive) [Homo sapiens] emb|CAI20324.1| polycystic kidney and hepatic disease 1 (autosomal r

  18. DYNC2LI1 mutations broaden the clinical spectrum of dynein-2 defects

    NARCIS (Netherlands)

    Kessler, K.; Wunderlich, I.; Uebe, S.; Falk, N.S.; Giessl, A.; Brandstatter, J.H.; Popp, B.; Klinger, P.; Ekici, A.B.; Sticht, H.; Dorr, H.G.; Reis, A.; Roepman, R.; Seemanova, E.; Thiel, C.T.

    2015-01-01

    Skeletal ciliopathies are a heterogeneous group of autosomal recessive osteochondrodysplasias caused by defects in formation, maintenance and function of the primary cilium. Mutations in the underlying genes affect the molecular motors, intraflagellar transport complexes (IFT), or the basal body. Th

  19. Disease: H01019 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available y mutations in the cardiac ryanodine receptor gene (RYR2) accounting for an autosomal dominant form (CPVT1) ...or mutations in the cardiac calsequestrin gene CASQ2 accounting for an autosomal recessive form (CPVT2). It

  20. Myo5b knockout mice as a model of microvillus inclusion disease

    NARCIS (Netherlands)

    Carton-Garcia, Fernando; Overeem, Arend W.; Nieto, Rocio; Bazzocco, Sarah; Dopeso, Higinio; Macaya, Irati; Bilic, Josipa; Landolfi, Stefania; Hernandez-Losa, Javier; Schwartz, Simo; Ramon y Cajal, Santiago; van Ijzendoorn, Sven C. D.; Arango, Diego

    2015-01-01

    Inherited MYO5B mutations have recently been associated with microvillus inclusion disease (MVID), an autosomal recessive syndrome characterized by intractable, life-threatening, watery diarrhea appearing shortly after birth. Characterization of the molecular mechanisms underlying this disease and d

  1. Treatment Development of Triheptanoin (G1D)

    Science.gov (United States)

    2017-02-28

    Epilepsy; GLUT1DS1; Glut1 Deficiency Syndrome 1, Autosomal Recessive; Glucose Metabolism Disorders; Glucose Transport Defect; Glucose Transporter Type 1 Deficiency Syndrome; Glucose Transporter Protein Type 1 Deficiency Syndrome

  2. Allogeneic haematopoietic stem cell transplantation for mitochondrial neurogastrointestinal encephalomyopathy

    NARCIS (Netherlands)

    Halter, Joerg P.; Schuepbach, W. Michael M.; Mandel, Hanna; Casali, Carlo; Orchard, Kim; Collin, Matthew; Valcarcel, David; Rovelli, Attilio; Filosto, Massimiliano; Dotti, Maria T.; Marotta, Giuseppe; Pintos, Guillem; Barba, Pere; Accarino, Anna; Ferra, Christelle; Illa, Isabel; Beguin, Yves; Bakker, Jaap A.; Boelens, Jaap J.; de Coo, Irenaeus F. M.; Fay, Keith; Sue, Carolyn M.; Nachbaur, David; Zoller, Heinz; Sobreira, Claudia; Simoes, Belinda Pinto; Hammans, Simon R.; Savage, David; Marti, Ramon; Chinnery, Patrick F.; Elhasid, Ronit; Gratwohl, Alois; Hirano, Michio

    2015-01-01

    Haematopoietic stem cell transplantation has been proposed as treatment for mitochondrial neurogastrointestinal encephalomyopathy, a rare fatal autosomal recessive disease due to TYMP mutations that result in thymidine phosphorylase deficiency. We conducted a retrospective analysis of all known pati

  3. Disease: H00143 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available idosis type III (ML III) are autosomal recessive lysosomal storage disorders caused by the deficiency of N-a...iency, mucolipidosis II/III and Niemann-Pick C1 disease - Lysosomal storage disorders

  4. Disease: H00849 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available tellectual disability and seizures are common to all three disorders. GAMT deficiency and AGAT deficiency ar...e creatine biosynthesis disorders and inherited in an autosomal recessive manner.

  5. Disease: H01143 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available lts from defective vitamin D receptors. Both diseases are rare autosomal recessive disorders characterized b...scription, gene) Malloy PJ, Feldman D Genetic disorders and defects in vitamin d

  6. Molecular characterization of WFS1 in patients with Wolfram syndrome

    NARCIS (Netherlands)

    Van den Ouweland, JMW; Cryns, K; Pennings, RJE; Walraven, [No Value; Janssen, GMC; Maassen, JA; Veldhuijzen, BFE; Arntzenius, AB; Lindhout, D; Cremers, CWRJ; Van Camp, G; Dikkeschei, LD

    2003-01-01

    Wolfram (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness) syndrome is a rare autosomal-recessive neurodegenerative disorder that is characterized by juvenile-onset diabetes mellitus, optic atrophy, diabetes insipidus, and sensorineural hearing impairment. A gene responsible for Wo

  7. Mitochondrial aspartyl-tRNA synthetase deficiency causes leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation.

    NARCIS (Netherlands)

    Scheper, G.C.; Klok, T. van der; Andel, R.J. van; Berkel, C.G. van; Sissler, M.; Smet, J.; Muravina, T.I.; Serkov, S.V.; Uziel, G.; Bugiani, M.; Schiffmann, R.; Krageloh-Mann, I.; Smeitink, J.A.M.; Florentz, C.; Coster, R. van; Pronk, J.C.; Knaap, M.S. van der

    2007-01-01

    Leukoencephalopathy with brain stem and spinal cord involvement and lactate elevation (LBSL) has recently been defined based on a highly characteristic constellation of abnormalities observed by magnetic resonance imaging and spectroscopy. LBSL is an autosomal recessive disease, most often manifesti

  8. Molecular characterization of WFS1 in patients with Wolfram syndrome.

    NARCIS (Netherlands)

    Ouweland, J.M.W. van den; Cryns, K.; Pennings, R.J.E.; Walraven, I.; Janssen, G.M.; Maassen, J.A.; Veldhuijzen, B.F.; Arntzenius, A.B.; Lindhout, D.; Cremers, C.W.R.J.; Camp, G. van; Dikkeschei, L.D.

    2003-01-01

    Wolfram (diabetes insipidus, diabetes mellitus, optic atrophy, and deafness) syndrome is a rare autosomal-recessive neurodegenerative disorder that is characterized by juvenile-onset diabetes mellitus, optic atrophy, diabetes insipidus, and sensorineural hearing impairment. A gene responsible for Wo

  9. Mandibuloacral Dysplasia in An Iranian Girl

    Directory of Open Access Journals (Sweden)

    F. Abbasi

    2006-07-01

    Full Text Available Mandibuloacral dysplasia (MAD is a rare autosomal recessive syndrome. Less than 25 families have been reported, most of which are Italian. Here, we describe a new patient of Iranian origin, born to consanguineous parents.

  10. Disease: H00447 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00447 HEM skeletal dysplasia; Greenberg dysplasia Hydrops ectopic calcification-mo...short limbs, and abnormal chondro-osseous calcification. It is inherited as an autosomal recessive trait. Ho

  11. Disease: H00766 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available betes appears during the first months of life in most patients and major skeletal m...ome is a rare autosomal recessive disorder characterized by neonatal insulin-requiring diabetes and spondyloepiphyseal dysplasia. Dia

  12. Sulfatide levels correlate with severity of neuropathy in metachromatic leukodystrophy

    DEFF Research Database (Denmark)

    Dali, Christine I; Barton, Norman W; Farah, Mohamed H;

    2015-01-01

    OBJECTIVE: Metachromatic leukodystrophy (MLD) is an autosomal recessive lysosomal storage disorder due to deficient activity of arylsulfatase A (ASA) that causes accumulation of sulfatide and lysosulfatide. The disorder is associated with demyelination and axonal loss in the central and periphera...

  13. Clinical spectrum of immunodeficiency, centromeric instability and facial dysmorphism (ICF syndrome).

    NARCIS (Netherlands)

    Hagleitner, M.M.; Lankester, A.; Maraschio, P.; Hulten, M.; Fryns, J.P.; Schuetz, C.; Gimelli, G.; Davies, E.G.; Gennery, A.; Belohradsky, B.H.; Groot, R. de; Gerritsen, E.J.; Mattina, T.; Howard, P.J.; Fasth, A.; Reisli, I.; Furthner, D.; Slatter, M.A.; Cant, A.J.; Cazzola, G.; Dijken, P.J. van; Deuren, M. van; Greef, J.C. de; Maarel, S.M. van der; Weemaes, C.M.R.

    2008-01-01

    BACKGROUND: Immunodeficiency, centromeric instability and facial dysmorphism (ICF syndrome) is a rare autosomal recessive disease characterised by facial dysmorphism, immunoglobulin deficiency and branching of chromosomes 1, 9 and 16 after PHA stimulation of lymphocytes. Hypomethylation of DNA of a

  14. Disease: H00159 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available mutation of ABCA1 gene leading to the accumulation of cholesterol in tissue macrophages and prevalent ather...H00159 Tangier disease Tangier disease is an autosomal recessive disorder caused by

  15. Disease: H00211 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available sis is an autosomal recessive iron metabolism disorder characterized by increased intestinal iron absorption, which leads to progress...ive accumulation of iron in the body. Inherited metabolic disease (HFE) HFE [HSA:30

  16. Disease: H01264 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available sive disease with immunodeficiency (VODI) is an autosomal recessive primary immunodeficiency associated with hepatic vascular occlusi...on and fibrosis. Mutations in the gene coding PML nuclear body protein Sp110 were f

  17. Mitochondrial abnormalities drive cell death in Wolfram syndrome 2

    Institute of Scientific and Technical Information of China (English)

    Tomotake Kanki; Daniel J Klionsky

    2009-01-01

    @@ Wolfram syndrome (WFS; MIM 222300) is an autosomal recessive disorder with highly variable clinical manifestations. It is characterized by di-abetes insipidus, diabetes mellitus, optic atrophy, and deafness (thus, known as DIDMOAD syndrome) [1].

  18. Disease: H01013 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available that was found to be highly associated with congenital cataract. The I and i antigens are carbohydrate struc...iation with autosomal recessive congenital cataracts. Invest Ophthalmol Vis Sci 45:1940-5 (2004) ...

  19. New RAB3GAP1 mutations in patients with Warburg Micro Syndrome from different ethnic backgrounds and a possible founder effect in the Danish

    DEFF Research Database (Denmark)

    Morris-Rosendahl, Deborah J; Segel, Reeval; Born, A Peter

    2010-01-01

    Warburg Micro Syndrome is a rare, autosomal recessive syndrome characterized by microcephaly, microphthalmia, microcornia, congenital cataracts, optic atrophy, cortical dysplasia, in particular corpus callosum hypoplasia, severe mental retardation, spastic diplegia, and hypogonadism. We have found...

  20. Disease: H00261 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ormations of the hands and feet. Nervous system disease; Kidney disease (MKS1) MKS1...hal, autosomal recessive disorder characterized by anomalies of the central nervous system, cystic dysplasia of the kidneys, and malf

  1. Three new families with arterial tortuosity syndrome.

    NARCIS (Netherlands)

    Wessels, M.W.; Catsman-Berrevoets, C.E.; Mancini, G.M.; Breuning, M.H.; Hoogeboom, J.J.; Stroink, H.; Frohn-Mulder, I.M.; Coucke, P.J.; Paepe, A.D.; Niermeijer, M.F.; Willems, P.J.

    2004-01-01

    Arterial tortuosity syndrome (ATS) is a rare condition with autosomal recessive inheritance characterized by connective tissue abnormalities. The most specific clinical findings are cardiovascular anomalies including tortuosity, lengthening, aneurysm, and stenosis formation of major arteries. Also v

  2. Normal expression of the Fanconi anemia proteins FAA and FAC and sensitivity to mitomycin C in two patients with Seckel syndrome

    NARCIS (Netherlands)

    Abou-Zahr, F; Bejjani, B; Kruyt, FAE; Kurg, R; Bacino, C; Shapira, SK; Youssoufian, H

    1999-01-01

    Seckel syndrome is a rare autosomal recessive disorder. The classical presentation includes pre- and postnatal growth deficiency, mental retardation, and characteristic facial appearance. There have been several reports of associated hematological abnormalities and chromosomal breakage, findings sug

  3. Unusual and severe disease course in a child with ataxia-telangiectasia.

    NARCIS (Netherlands)

    Meyts, I.; Weemaes, C.M.R.; Wolf-Peeters, C. de; Proesmans, M.; Renard, M.; Uyttebroeck, A.; Boeck, K. de

    2003-01-01

    Ataxia-telangiectasia (AT) is an autosomal recessive syndrome of combined immunodeficiency. Hallmarks of the disease comprise progressive cerebellar ataxia, oculocutaneous telangiectasia, cancer susceptibility and variable humoral and cellular immunodeficiency. We describe a patient with AT presenti

  4. Pyridoxine-dependent seizures and microcephaly.

    Science.gov (United States)

    Tan, Hüseyin; Kardaş, Fatih; Büyükavci, Mustafa; Karakelleoğlu, Cahit

    2004-09-01

    Pyridoxine dependency is a rare autosomal-recessive disorder causing intractable seizures in neonates and infants. This case report describes an infant with pyridoxine-dependent seizures with microcephaly and discusses a probable pathogenetic mechanism of microcephaly in this condition.

  5. Neuropathies optiques héréditaires

    DEFF Research Database (Denmark)

    Milea, D; Verny, C

    2012-01-01

    Hereditary optic neuropathies are a group of heterogeneous conditions affecting both optic nerves, with an autosomal dominant, autosomal recessive, X-related or mitochondrial transmission. The two most common non-syndromic hereditary optic neuropathies (Leber's hereditary optic neuropathy...

  6. Mutations in SPATA5 Are Associated with Microcephaly, Intellectual Disability, Seizures, and Hearing Loss

    NARCIS (Netherlands)

    Tanaka, Akemi J.; Cho, Megan T.; Millan, Francisca; Juusola, Jane; Retterer, Kyle; Joshi, Charuta; Niyazov, Dmitriy; Garnica, Adolfo; Gratz, Edward; Deardorff, Matthew; Wilkins, Alisha; Ortiz-Gonzalez, Xilma; Mathews, Katherine; Panzer, Karin; Brilstra, Eva; Van Gassen, Koen L I; Volker-Touw, Catharina M L; van Binsbergen, Ellen; Sobreira, Nara; Hamosh, Ada; McKnight, Dianalee; Monaghan, Kristin G.; Chung, Wendy K.

    2015-01-01

    Using whole-exome sequencing, we have identified in ten families 14 individuals with microcephaly, developmental delay, intellectual disability, hypotonia, spasticity, seizures, sensorineural hearing loss, cortical visual impairment, and rare autosomal-recessive predicted pathogenic variants in sper

  7. Genetics of Infantile Bilateral Striatal Necrosis

    Directory of Open Access Journals (Sweden)

    J Gordon Millichap

    2006-09-01

    Full Text Available The gene mutation causing autosomal recessive infantile bilateral striatal necrosis (IBSN was identified in eight consanguineous Israeli Bedouin families, in a study at Schneider Children’s Medical Center, Petah Tikva, Israel, and other centers.

  8. A CONSANGUINEOUS MATING COUPLE AND THEIR CONCOMITANT ESOTROPIA TWINS

    Institute of Scientific and Technical Information of China (English)

    1991-01-01

    A first cousin marriage couple and their 8-year-old identical twin daughters with concomitant strabismus are described.This family would indicate an autosomal recessive inheritance in concomitant strabismus.

  9. The effect of light deprivation in patients with Stargardt disease

    NARCIS (Netherlands)

    Teussink, M.M.; Lee, M.D.; Smith, R.T.; Huet, R.A.C. van; Klaver, C.C.; Klevering, B.J.; Theelen, T.; Hoyng, C.B.

    2015-01-01

    PURPOSE: To investigate whether long-term protection from light exposure affects the rate of disease progression in patients with autosomal recessive Stargardt disease (STGD1), measured using fundus autofluorescence imaging. DESIGN: Longitudinal, retrospective, interventional case series. METHODS: F

  10. Ny klassifikation og molekylærgenetisk viden om arvelig iktyose

    DEFF Research Database (Denmark)

    Andersen, Rikke Elkjær; Hertz, Jens Michael; Bygum, Anette

    2014-01-01

    A new classification of inherited ichthyoses is presented based on clinical features, genetic background and pathophysiology. Ichthyoses are disorders of cornification and may be part of syndromes. Ichthyosis vulgaris, X-linked ichthyosis, autosomal recessive congenital ichthyosis and syndrome...

  11. Localization of the gene for sclerosteosis to the van Buchem Disease-gene region on chromosome 17q12-q21

    NARCIS (Netherlands)

    Balemans, W; Van Den Ende, J; Paes-Alves, AF; Dikkers, FG; Willems, PJ; Vanhoenacker, F; de Almeida-Melo, N; Alves, CF; Stratakis, CA; Hill, SC; Van Hul, W

    1999-01-01

    Sclerosteosis is an uncommon, autosomal recessive, progressive, sclerosing, bone dysplasia characterized by generalized osteosclerosis and hyperostosis of the skeleton, affecting mainly the skull and mandible. In most patients this causes facial paralysis and hearing loss. Other features are giganti

  12. An overview of L-2-hydroxyglutarate dehydrogenase gene (L2HGDH) variants: a genotype-phenotype study

    DEFF Research Database (Denmark)

    Steenweg, Marjan E; Jakobs, Cornelis; Errami, Abdellatif;

    2010-01-01

    L-2-Hydroxyglutaric aciduria (L2HGA) is a rare, neurometabolic disorder with an autosomal recessive mode of inheritance. Affected individuals only have neurological manifestations, including psychomotor retardation, cerebellar ataxia, and more variably macrocephaly, or epilepsy. The diagnosis of ...

  13. Fraser syndrome : epidemiological study in a European population

    NARCIS (Netherlands)

    Barisic, Ingeborg; Odak, Ljubica; Loane, Maria; Garne, Ester; Wellesley, Diana; Calzolari, Elisa; Dolk, Helen; Addor, Marie-Claude; Arriola, Larraitz; Bergman, Jorieke; Bianca, Sebastiano; Boyd, Patricia A; Draper, Elizabeth S; Gatt, Miriam; Haeusler, Martin; Khoshnood, Babak; Latos-Bielenska, Anna; McDonnell, Bob; Pierini, Anna; Rankin, Judith; Rissmann, Anke; Queisser-Luft, Annette; Verellen-Dumoulin, Christine; Stone, David; Tenconi, Romano

    2013-01-01

    Fraser syndrome is a rare autosomal recessive disorder characterized by cryptophthalmos, cutaneous syndactyly, laryngeal, and urogenital malformations. We present a population-based epidemiological study using data provided by the European Surveillance of Congenital Anomalies (EUROCAT) network of bi

  14. Disease: H00999 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available festations, including pure myopathy, myopathy with encephalopathy, cerebellar atrop...H00999 Coenzyme Q10 deficiency Coenzyme Q10 deficiency is an autosomal recessive disorder with variable mani

  15. Unreported manifestations in two Dutch families with Bartsocas-Papas syndrome

    NARCIS (Netherlands)

    Veenstra-Knol, HE; Kleibeuker, A; Timmer, A; ten Kate, LP; van Essen, AJ

    2003-01-01

    Bartsocas-Papas syndrome (BPS) is a severe autosomal recessive syndrome characterized by neonatal or intrauterine death in most cases, severe popliteal webbing, oligosyndactyly, genital abnormalities, and typical face with short palpebral fissures, ankylo-blepharon, hypoplastic nose, orofacial cleft

  16. Disease: H01304 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H01304 Hyperglycinuria Hyperglycinuria (HG) is an autosomal recessive abnormality o...alczuk S, Ng C, Vanslambrouck JM, Rodgers H, Auray-Blais C, Cavanaugh JA, Broer A, Rasko JE Iminoglycinuria and hype

  17. Disease: H00188 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00188 Hyperlysinemia Hyperlysinemia is an autosomal recessive metabolic disorder c... alpha-aminoadipic semialdehyde synthase gene, which is defective in familial hyperlysinemia. Am J Hum Genet 66:1736-43 (2000) ...

  18. Identifying genes responsible for intellectual disability in consanguineous families

    NARCIS (Netherlands)

    Iqbal, Z.; Bokhoven, H. van

    2014-01-01

    Consanguinity is an important determinant of birth defects including intellectual disability (ID). Consanguineous populations have a relative high prevalence of autosomal recessive forms of intellectual disability (ARID), which constitute a highly heterogeneous group of disorders both in their clini

  19. Associations among genotype, clinical phenotype, and intracellular localization of trafficking proteins in ARC syndrome

    NARCIS (Netherlands)

    Smith, Holly; Galmes, Romain; Gogolina, Ekaterina; Straatman-Iwanowska, Anna; Reay, Kim; Banushi, Blerida; Bruce, Christopher K.; Cullinane, Andrew R.; Romero, Rene; Chang, Richard; Ackermann, Oanez; Baumann, Clarisse; Cangul, Hakan; Celik, Fatma Cakmak; Aygun, Canan; Coward, Richard; Dionisi-Vici, Carlo; Sibbles, Barbara; Inward, Carol; Kim, Chong Ae; Klumperman, Judith; Knisely, A. S.; Watson, Steven P.; Gissen, Paul

    2012-01-01

    Arthrogryposisrenal dysfunctioncholestasis (ARC) syndrome is a rare autosomal recessive multisystem disorder caused by mutations in vacuolar protein sorting 33 homologue B (VPS33B) and VPS33B interacting protein, apicalbasolateral polarity regulator (VIPAR). Cardinal features of ARC include congenit

  20. Disease: H00614 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00614 Infantile systemic hyalinosis and juvenile hyaline fibromatosis Infantile sy...stemic hyalinosis (ISH) and juvenile hyaline fibromatosis (JHF) are autosomal recessive diseases with consid

  1. Nutrition in Cystic Fibrosis: Macro- and Micronutrients

    NARCIS (Netherlands)

    Oudshoorn, Johanna Hermiena

    2006-01-01

    Cystic fibrosis (CF) is the most common life-threatening autosomal recessive inherited disease in Caucasians, and is characterized by progressive lung disease, pancreatic insufficiency, malnutrition, hepatobiliary disease and elevated sweat electrolyte levels. The increased survival of CF patients d

  2. Meier-Gorlin syndrome Clinical genetics and genomics

    NARCIS (Netherlands)

    De Munnik, Sonja A.; Hoefsloot, Elisabeth H.; Roukema, Jolt; Schoots, Jeroen; Knoers, Nine Vam; Brunner, Han G.; Jackson, Andrew P.; Bongers, Ernie Mhf

    2015-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females a

  3. Meier-Gorlin syndrome

    NARCIS (Netherlands)

    Munnik, S.A. de; Hoefsloot, E.H.; Roukema, J.; Schoots, J.; Knoers, N.V.A.M.; Brunner, H.G.; Jackson, A.P.; Bongers, E.M.H.F.

    2015-01-01

    Meier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia in females a

  4. Meier-Gorlin syndrome Clinical genetics and genomics

    NARCIS (Netherlands)

    S. de Munnik (Sonja); E.H. Hoefsloot (Elisabeth H.); J. Roukema (Jolt); J. Schoots (Jeroen); N.V.A.M. Knoers (Nine); H.G. Brunner; A.P. Jackson (Andrew); E. Bongers (Ernie)

    2015-01-01

    textabstractMeier-Gorlin syndrome (MGS) is a rare autosomal recessive primordial dwarfism disorder, characterized by microtia, patellar applasia/hypoplasia, and a proportionate short stature. Associated clinical features encompass feeding problems, congenital pulmonary emphysema, mammary hypoplasia

  5. Disease: H01003 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available atine kinase. Dimethylglycine dehydrogenase (DMGDH) is a mitochondrial matrix enzym...ase deficiency is a rare autosomal recessive disorder characterized by fish odor, and unusual muscle fatigue with increased serum cre

  6. POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome

    NARCIS (Netherlands)

    van Reeuwijk, J; Janssen, M; van den Elzen, C; de Bernabe, DBV; Sabatelli, P; Merlini, L; Boon, M; Scheffer, H; Brockington, M; Muntoni, F; Huynen, MA; Verrips, A; Walsh, CA; Barth, PG; Brunner, HG; van Bokhoven, H

    2005-01-01

    Background: Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterised by congenital muscular dystrophy, structural brain defects, and eye malformations. Typical brain abnormalities are hydrocephalus, lissencephaly, agenesis of the corpus callosum, fusion of the hemispheres, cer

  7. Ataxia-telangiectasia: Linkage analysis in highly inbred Arab and Druze families and differentiation from an ataxia-microcephaly-cataract syndrome

    NARCIS (Netherlands)

    Y. Ziv (Yael); M. Frydman (Moshe); E.M. Lange (Ethan); N. Zelnik (N.); G. Rotman (Galit); C. Julier (C.); N.G.J. Jaspers (Nicolaas); E. Dagan (Efrat); D. Abeliovicz (Dvorah); H. Dar (H.); Z. Borochowitz (Z.); M. Lathrop (Mark); A. Gatti (Arianna); Y. Shiloh (Yosef)

    1992-01-01

    textabstractAtaxia-telangiectasia (A-T) is a progressive autosomal recessive disease featuring neurodegeneration, immunodeficiency, chromosomal instability, radiation sensitivity and a highly increased proneness to cancer. A-T is ethnically widespread and genetically heterogeneous, as indicated by t

  8. POMT2 mutations cause alpha-dystroglycan hypoglycosylation and Walker-Warburg syndrome.

    NARCIS (Netherlands)

    Reeuwijk, J. van; Janssen, M.; Elzen, C. van der; Beltran Valero de Bernabe, D.; Sabatelli, P.; Merlini, L.; Boon, M.; Scheffer, H.; Brockington, M.; Muntoni, F.; Huynen, M.A.; Verrips, A.; Walsh, C.A.; Barth, P.G.; Brunner, H.G.; Bokhoven, J.H.L.M. van

    2005-01-01

    BACKGROUND: Walker-Warburg syndrome (WWS) is an autosomal recessive condition characterised by congenital muscular dystrophy, structural brain defects, and eye malformations. Typical brain abnormalities are hydrocephalus, lissencephaly, agenesis of the corpus callosum, fusion of the hemispheres, cer

  9. Pantethine treatment is effective in recovering the disease phenotype induced by ketogenic diet in a pantothenate kinase-associated neurodegeneration mouse model

    NARCIS (Netherlands)

    Brunetti, Dario; Dusi, Sabrina; Giordano, Carla; Lamperti, Costanza; Morbin, Michela; Fugnanesi, Valeria; Marchet, Silvia; Fagiolari, Gigliola; Sibon, Ody; Moggio, Maurizio; d'Amati, Giulia; Tiranti, Valeria

    2014-01-01

    Pantothenate kinase-associated neurodegeneration, caused by mutations in the PANK2 gene, is an autosomal recessive disorder characterized by dystonia, dysarthria, rigidity, pigmentary retinal degeneration and brain iron accumulation. PANK2 encodes the mitochondrial enzyme pantothenate kinase type 2,

  10. Scheie syndrome

    Science.gov (United States)

    ... Diagnosis and Treatment . 5th ed. New York, NY: Springer; 2012:chap 40. Read More Autosomal recessive Cloudy ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  11. Hereditary fructose intolerance

    Science.gov (United States)

    ... Diagnosis and Treatment . 5th ed. New York, NY: Springer; 2012:chap 9. Read More Autosomal recessive Enzyme ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  12. Morquio syndrome

    Science.gov (United States)

    ... Diagnosis and Treatment . 5th ed. New York, NY: Springer; 2012:chap 40. Read More Autosomal recessive Enzyme ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  13. Krabbe disease

    Science.gov (United States)

    ... Diagnosis and Treatment . 5th ed. New York, NY: Springer; 2012:chap 39. Read More Autosomal recessive Blindness ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  14. Sanfilippo syndrome

    Science.gov (United States)

    ... Diagnosis and Treatment . 5th ed. New York, NY: Springer; 2012:chap 40. Read More Autosomal recessive Enzyme ... medical conditions. Call 911 for all medical emergencies. Links to other sites are provided for information only -- ...

  15. Disease: H00941 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available g tendency, FXII is an important protease that plays a major role in the initiation of the intrinsic pathway...y is a rare autosomal recessive disorder. Although FXII deficiency is not associated with a clinical bleedin

  16. Disease: H00092 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ferentiation, along with direct or indirect impairment of B-cell development and function. Adenosine deaminase (ADA) deficiency accou...nts for about half of the autosomal recessive forms of S

  17. The incidence of HLA-SD antigens in recessive retinitis pigmentosa.

    Science.gov (United States)

    Chen, M C; Marak, G E; Pilkerton, A R

    1978-01-01

    Eighteen patients with recessive retinitis pigmentosa were tissue typed for HLA-SD antigens. There was no evidence that a particular HLA-SD antigen was associated with autosomal recessive retinitis pigmentosa. PMID:638110

  18. Clinical, neuroradiological and genetic findings in pontocerebellar hypoplasia

    NARCIS (Netherlands)

    Namavar, Yasmin; Barth, Peter G; Kasher, Paul R; van Ruissen, Fred; Brockmann, Knut; Bernert, Günther; Writzl, Karin; Ventura, Karen; Cheng, Edith Y; Ferriero, Donna M; Basel-Vanagaite, Lina; Eggens, Veerle R C; Krägeloh-Mann, Ingeborg; De Meirleir, Linda; King, Mary; Graham, John M; von Moers, Arpad; Knoers, Nine; Sztriha, Laszlo; Korinthenberg, Rudolf; Dobyns, William B; Baas, Frank; Poll-The, Bwee Tien; Sival, Deborah

    2011-01-01

    Pontocerebellar hypoplasia is a group of autosomal recessive neurodegenerative disorders with prenatal onset. The common characteristics are cerebellar hypoplasia with variable atrophy of the cerebellum and the ventral pons. Supratentorial involvement is reflected by variable neocortical atrophy, ve

  19. Renal function in tyrosinaemia type I after liver transplantation : A long-term follow-up

    NARCIS (Netherlands)

    Pierik, LJWM; van Spronsen, FJ; Bijleveld, CMA; van Dael, CML

    2005-01-01

    Hereditary tyrosinaemia type I is an autosomal recessive inborn error of tyrosine catabolism caused by a deficiency of the enzyme fumarylacetoacetase that results in liver failure, hepatocellular carcinoma, renal tubular dysfunction and acute intermittent porphyria. When treated with liver transplan

  20. Haemochromatosis gene frequency in a control and diabetic Irish population.

    LENUS (Irish Health Repository)

    Kirk, L

    2009-03-01

    Hereditary haemochromatosis is inherited in an autosomal recessive manner. Two major mutations have been identified and the condition is emerging as one of the most common recessive mutations among subjects of Northern European descendants.

  1. Disease: H00214 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ); X-Linked recessive hypophosphatemia (XLRH); Autosomal dominant hypophosphatemic rickets (ADHR); Autosomal...Hadad Y, Goding J, Parvari R Autosomal-recessive hypophosphatemic rickets is asso

  2. Sequence Classification: 890773 [

    Lifescience Database Archive (English)

    Full Text Available oline as sole nitrogen source; deficiency of the human homolog causes HPII, an autosomal recessive inborn error of metabolism; Put2p || http://www.ncbi.nlm.nih.gov/protein/6321826 ...

  3. Leucocyte adhesion deficiency type 1 with developmental delay secondary to CMV infection and filiation questions.

    Science.gov (United States)

    Strickler, Alexis; Gallo, Silvanna; King, Alejandra; Rosenzweig, Sergio D

    2015-04-09

    Leucocyte adhesion deficiency (LAD) is a group of rare autosomal recessive (T; p.C612F, and led us to suspect a biological parent other than the legal father and, therefore, an unwanted social situation.

  4. UAB HRFD Core Center: Core A: The Hepato/Renal Fibrocystic Diseases Translational Resource

    Science.gov (United States)

    2016-08-23

    Hepato/Renal Fibrocystic Disease; Autosomal Recessive Polycystic Kidney Disease; Joubert Syndrome; Bardet Biedl Syndrome; Meckel-Gruber Syndrome; Congenital Hepatic Fibrosis; Caroli Syndrome; Oro-Facial-Digital Syndrome Type I; Nephronophthisis; Glomerulocystic Kidney Disease

  5. Disease: H00971 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available alence of 1 in 33,000 individuals. It is characterized by low visual aquity, photop...H00971 Achromatopsia; Rod monochromacy Achromatopsia is an autosomal recessive retinal dystrophy with a prev

  6. Schimke immunoosseous dysplasia: Defining skeletal features

    NARCIS (Netherlands)

    K.B. Hunter (Kshamta); T. Lücke (Thomas); J. Spranger (Jürgen); S.F. Smithson (Sarah); H. Alpay (Harika); J.-L. André (Jean-Luc); Y. Asakura (Yumi); R. Bogdanovic (Radovan); D. Bonneau (Dominique); R. Cairns (Robyn); K. Cransberg (Karlien); S. Fründ (Stefan); H. Fryssira (Helen); D. Goodman (David); K. Helmke (Knut); B. Hinkelmann (Barbara); G. Lama (Guiliana); P. Lamfers (Petra); C. Loirat (Chantal); S. Majore (Silvia); C. Mayfield (Christy); B.F. Pontz (Betram); C. Rusu (Christina); J.M. Saraiva (Jorge); B. Schmidt (Beate); L. Schoemaker (Lawrence); S. Sigaudy (Sabine); N. Stajic (Natasa); D. Taha (Doris); C.F. Boerkoel (Cornelius)

    2010-01-01

    textabstractSchimke immunoosseous dysplasia (SIOD) is an autosomal recessive multisystem disorder characterized by prominent spondyloepiphyseal dysplasia, T cell deficiency, and focal segmental glomerulosclerosis. Biallelic mutations in swi/snf-related, matrix-associated, actin-dependent regulator o

  7. Disease: H01283 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available a rare autosomal recessive disease characterized by developmental delay, seizure, hypoglycemia, cardiomyopa...D gene that encodes MCD, result in a deficiency of MCD activity. Inherited metabolic disease hsa00410(23417)

  8. Disease: H01146 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H01146 Aminoacylase 1 deficiency Aminoacylase 1 deficiency is an autosomal recessive disea...ave been reported. Inherited metabolic disease; Neurodegenerative disease hsa0033... deficiency causes spongy degeneration of the brain known as Canavan disease [DS:

  9. Disease: H01285 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available cblG) is an autosomal recessive disease characterized by homocystinuria, hyperhomocysteinemia, and hypomethi...oninemia. Mutations in the MTR gene, which encodes methionine synthase result in this disease. Inherited metabolic disea

  10. Clinical and genetic aspects of generalized aggressive periodontitis in families of Tumkur district of Karnataka, India

    Directory of Open Access Journals (Sweden)

    Vaibhavi Joshipura

    2013-01-01

    Conclusion: The disorder may not be segregating as an autosomal recessive trait and we could have been misled by consanguinity in the family. It could be a multifactorial trait, or it could be still segregating as an autosomal recessive trait, but the region of homozygosity could be small and we failed to detect it using microsatellite markers. Therefore, SNP-marker-based analysis is warranted in future.

  11. Disease: H00734 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00734 Lamellar ichthyosis (LI) and Non-bullous congenital ichthyosiform erythroder...ma (NBCIE) Autosomal recessive congenital ichthyoses comprise a heterogeneous group of skin disorders of hyp...erkeratosis. Two non-syndromic forms are defined including lamellar ichthyosis (LI) and non-bullous congenital...OXE3 [HSA:59344] ICHYN [HSA:348938] CYP4F22 [HSA:126410] [KO:K17731] Bullous congenital ichthyosiform erythr...(description, gene) Akiyama M Harlequin ichthyosis and other autosomal recessive congenital

  12. DVL1 frameshift mutations clustering in the penultimate exon cause autosomal-dominant Robinow syndrome

    DEFF Research Database (Denmark)

    White, Janson; Mazzeu, Juliana F; Hoischen, Alexander

    2015-01-01

    Robinow syndrome is a genetically heterogeneous disorder characterized by mesomelic limb shortening, genital hypoplasia, and distinctive facial features and for which both autosomal-recessive and autosomal-dominant inheritance patterns have been described. Causative variants in the non-canonical ......Robinow syndrome is a genetically heterogeneous disorder characterized by mesomelic limb shortening, genital hypoplasia, and distinctive facial features and for which both autosomal-recessive and autosomal-dominant inheritance patterns have been described. Causative variants in the non...

  13. Experience of a single center with congenital hepatic fibrosis:A review of the literature

    Institute of Scientific and Technical Information of China (English)

    Ali; Shorbagi; Yusuf; Bayraktar

    2010-01-01

    Congenital hepatic fibrosis(CHF) is an autosomal recessive inherited malformation defined pathologically by a variable degree of periportal fibrosis and irregularly shaped proliferating bile ducts.It is one of the fibropolycystic diseases,which also include Caroli disease,autosomal dominant polycystic kidney disease,and autosomal recessive polycystic kidney disease. Clinically it is characterized by hepatic fibrosis,portal hypertension,and renal cystic disease.CHF is known to occur in association with a ran...

  14. NCBI nr-aa BLAST: CBRC-FRUB-02-0208 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-FRUB-02-0208 emb|CAP09515.1| novel gene similar to vertebrate polycystic kidne...y and hepatic disease 1 (autosomal recessive)-like 1 (PKHD1L1) [Danio rerio] emb|CAP09460.1| novel gene similar to vertebrate polycys...tic kidney and hepatic disease 1 (autosomal recessive)-like 1 (PKHD1L1) [Danio rerio] CAP09515.1 1e-111 42% ...

  15. Disease: H00753 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00753 Urofacial syndrome The urofacial syndrome (UFS) is an autosomal recessive di...sorder characterized by the combination of urological problems and distorted facial expression. Failure of t...S, Rana S, Nurnberg P, Hubner C First HPSE2 missense mutation in urofacial syndro... HPSE2 Cause the Autosomal Recessive Urofacial Syndrome. Am J Hum Genet (2010) PM...ith R, Woolf AS, Black GC, Newman WG Mutations in HPSE2 Cause Urofacial Syndrome. Am J Hum Genet (2010) ...

  16. Rare Disease Patient Registry & Natural History Study - Coordination of Rare Diseases at Sanford

    Science.gov (United States)

    2016-09-01

    -Hirschhorn Syndrome; 4p16.3 Microduplication Syndrome; 4p Deletion Syndrome, Non-Wolf-Hirschhorn Syndrome; Autosomal Recessive Stickler Syndrome; Stickler Syndrome Type 2; Stickler Syndrome Type 1; Stickler Syndrome; Mucolipidosis Type 4; X-linked Spinocerebellar Ataxia Type 4; X-linked Spinocerebellar Ataxia Type 3; X-linked Intellectual Disability - Ataxia - Apraxia; X-linked Progressive Cerebellar Ataxia; X-linked Non Progressive Cerebellar Ataxia; X-linked Cerebellar Ataxia; Vitamin B12 Deficiency Ataxia; Toxic Exposure Ataxia; Unclassified Autosomal Dominant Spinocerebellar Ataxia; Thyroid Antibody Ataxia; Sporadic Adult-onset Ataxia of Unknown Etiology; Spinocerebellar Ataxia With Oculomotor Anomaly; Spinocerebellar Ataxia With Epilepsy; Spinocerebellar Ataxia With Axonal Neuropathy Type 2; Spinocerebellar Ataxia Type 8; Spinocerebellar Ataxia Type 7; Spinocerebellar Ataxia Type 6; Spinocerebellar Ataxia Type 5; Spinocerebellar Ataxia Type 4; Spinocerebellar Ataxia Type 37; Spinocerebellar Ataxia Type 36; Spinocerebellar Ataxia Type 35; Spinocerebellar Ataxia Type 34; Spinocerebellar Ataxia Type 32; Spinocerebellar Ataxia Type 31; Spinocerebellar Ataxia Type 30; Spinocerebellar Ataxia Type 3; Spinocerebellar Ataxia Type 29; Spinocerebellar Ataxia Type 28; Spinocerebellar Ataxia Type 27; Spinocerebellar Ataxia Type 26; Spinocerebellar Ataxia Type 25; Spinocerebellar Ataxia Type 23; Spinocerebellar Ataxia Type 22; Spinocerebellar Ataxia Type 21; Spinocerebellar Ataxia Type 20; Spinocerebellar Ataxia Type 2; Spinocerebellar Ataxia Type 19/22; Spinocerebellar Ataxia Type 18; Spinocerebellar Ataxia Type 17; Spinocerebellar Ataxia Type 16; Spinocerebellar Ataxia Type 15/16; Spinocerebellar Ataxia Type 14; Spinocerebellar Ataxia Type 13; Spinocerebellar Ataxia Type 12; Spinocerebellar Ataxia Type 11; Spinocerebellar Ataxia Type 10; Spinocerebellar Ataxia Type 1 With Axonal Neuropathy; Spinocerebellar Ataxia Type 1; Spinocerebellar Ataxia - Unknown; Spinocerebellar Ataxia - Dysmorphism

  17. Msx2 -/- transgenic mice develop compound amelogenesis imperfecta, dentinogenesis imperfecta and periodental osteopetrosis.

    Science.gov (United States)

    Aïoub, M; Lézot, F; Molla, M; Castaneda, B; Robert, B; Goubin, G; Néfussi, J R; Berdal, A

    2007-11-01

    The physiological function of the transcription factor Msx2 in tooth and alveolar bone was analysed using a knock-in transgenic mouse line. In this mouse line, the beta-galactosidase gene was used to disrupt Msx2: thus, beta-galactosidase expression was driven by the Msx2 promoter, but Msx2 was not produced. This allowed to monitor Msx2 expression using a beta-galactosidase assay. Msx2 transgenic mice ubiquitously and continuously expressed the mutated Msx2-nlacZ gene in cells of the complex formed by tooth and alveolar bone. Msx2 -/- homozygous mice displayed a wide spectrum of alterations in tooth eruption and morphology as well as dental and periodontal defects from the first post-natal weeks up to 6 months. These defects culminated with the formation of an odontogenic tumour at the mandibular third molar site. This study suggests that bone resorption is a functional target of Msx2 in the alveolar compartment, since Msx2 was expressed in osteoclasts, with the highest expression levels found in the active sites of bone modelling associated with tooth eruption and root elongation. The RANK osteoclast differentiation pathway was affected in microdissected Msx2 -/- mouse alveolar bone (as inferred by RANK ligand mRNA levels) compared to basal bone and wild-type controls. Decreased alveolar osteoclast activity was observed in Msx2 -/- mice, similar to that seen in osteopetrosis, another condition in which osteoclast activity is impaired and odontogenic tumours form. These data suggest a pleiotropic role for Msx2 in oral bone growth from birth until adult homeostasis. RANK pathway appeared to be modulated by Msx2, in addition to the previously reported modulations of BMP4 and laminin5alpha3 in early tooth development. Non-overlapping Msx1 and Msx2 expression patterns suggested that these two homeogenes play non-redundant roles in skeletal growth, with Msx1 targeting basal bone and Msx2 targeting alveolar bone. This study provides a detailed analysis of the phenotype resulting from the Msx2 null mutation and identifies the impact of Msx1 and Msx2 on post-natal oral bone growth.

  18. Ameloblast modulation and transport of Cl-, Na+, and K+ during amelogenesis

    NARCIS (Netherlands)

    Bronckers, A.L.J.J.; Lyaruu, D.; Jalali, R.; Medina, J.F.; Zandieh-Doulabi, B.; DenBesten, P.K.

    2015-01-01

    Ameloblasts express transmembrane proteins for transport of mineral ions and regulation of pH in the enamel space. Two major transporters recently identified in ameloblasts are the Na+K+-dependent calcium transporter NCKX4 and the Na+-dependent HPO42- (Pi) cotransporter NaPi-2b. To regulate pH, amel

  19. Ameloblast Modulation and Transport of Cl⁻, Na⁺, and K⁺ during Amelogenesis.

    Science.gov (United States)

    Bronckers, A L J J; Lyaruu, D; Jalali, R; Medina, J F; Zandieh-Doulabi, B; DenBesten, P K

    2015-12-01

    Ameloblasts express transmembrane proteins for transport of mineral ions and regulation of pH in the enamel space. Two major transporters recently identified in ameloblasts are the Na(+)K(+)-dependent calcium transporter NCKX4 and the Na(+)-dependent HPO4 (2-) (Pi) cotransporter NaPi-2b. To regulate pH, ameloblasts express anion exchanger 2 (Ae2a,b), chloride channel Cftr, and amelogenins that can bind protons. Exposure to fluoride or null mutation of Cftr, Ae2a,b, or Amelx each results in formation of hypomineralized enamel. We hypothesized that enamel hypomineralization associated with disturbed pH regulation results from reduced ion transport by NCKX4 and NaPi-2b. This was tested by correlation analyses among the levels of Ca, Pi, Cl, Na, and K in forming enamel of mice with null mutation of Cftr, Ae2a,b, and Amelx, according to quantitative x-ray electron probe microanalysis. Immunohistochemistry, polymerase chain reaction analysis, and Western blotting confirmed the presence of apical NaPi-2b and Nckx4 in maturation-stage ameloblasts. In wild-type mice, K levels in enamel were negatively correlated with Ca and Cl but less negatively or even positively in fluorotic enamel. Na did not correlate with P or Ca in enamel of wild-type mice but showed strong positive correlation in fluorotic and nonfluorotic Ae2a,b- and Cftr-null enamel. In hypomineralizing enamel of all models tested, 1) Cl(-) was strongly reduced; 2) K(+) and Na(+) accumulated (Na(+) not in Amelx-null enamel); and 3) modulation was delayed or blocked. These results suggest that a Na(+)K(+)-dependent calcium transporter (likely NCKX4) and a Na(+)-dependent Pi transporter (potentially NaPi-2b) located in ruffle-ended ameloblasts operate in a coordinated way with the pH-regulating machinery to transport Ca(2+), Pi, and bicarbonate into maturation-stage enamel. Acidification and/or associated physicochemical/electrochemical changes in ion levels in enamel fluid near the apical ameloblast membrane may reduce the transport activity of mineral transporters, which results in hypomineralization.

  20. Bmp2 deletion causes an amelogenesis imperfecta phenotype via regulating enamel gene expression.

    Science.gov (United States)

    Guo, Feng; Feng, Junsheng; Wang, Feng; Li, Wentong; Gao, Qingping; Chen, Zhuo; Shoff, Lisa; Donly, Kevin J; Gluhak-Heinrich, Jelica; Chun, Yong Hee Patricia; Harris, Stephen E; MacDougall, Mary; Chen, Shuo

    2015-08-01

    Although Bmp2 is essential for tooth formation, the role of Bmp2 during enamel formation remains unknown in vivo. In this study, the role of Bmp2 in regulation of enamel formation was investigated by the Bmp2 conditional knock out (Bmp2 cKO) mice. Teeth of Bmp2 cKO mice displayed severe and profound phenotypes with asymmetric and misshaped incisors as well as abrasion of incisors and molars. Scanning electron microscopy analysis showed that the enamel layer was hypoplastic and enamel lacked a typical prismatic pattern. Teeth from null mice were much more brittle as tested by shear and compressive moduli. Expression of enamel matrix protein genes, amelogenin, enamelin, and enamel-processing proteases, Mmp-20 and Klk4 was reduced in the Bmp2 cKO teeth as reflected in a reduced enamel formation. Exogenous Bmp2 up-regulated those gene expressions in mouse enamel organ epithelial cells. This result for the first time indicates Bmp2 signaling is essential for proper enamel development and mineralization in vivo.

  1. Stress Response Pathways in Ameloblasts: Implications for Amelogenesis and Dental Fluorosis

    Directory of Open Access Journals (Sweden)

    John D. Bartlett

    2012-08-01

    Full Text Available Human enamel development of the permanent teeth takes place during childhood and stresses encountered during this period can have lasting effects on the appearance and structural integrity of the enamel. One of the most common examples of this is the development of dental fluorosis after childhood exposure to excess fluoride, an elemental agent used to increase enamel hardness and prevent dental caries. Currently the molecular mechanism responsible for dental fluorosis remains unknown; however, recent work suggests dental fluorosis may be the result of activated stress response pathways in ameloblasts during the development of permanent teeth. Using fluorosis as an example, the role of stress response pathways during enamel maturation is discussed.

  2. Enamel-free teeth: Tbx1 deletion affects amelogenesis in rodent incisors.

    Science.gov (United States)

    Catón, Javier; Luder, Hans-Ulrich; Zoupa, Maria; Bradman, Matthew; Bluteau, Gilles; Tucker, Abigail S; Klein, Ophir; Mitsiadis, Thimios A

    2009-04-15

    TBX1 is a principal candidate gene for DiGeorge syndrome, a developmental anomaly that affects the heart, thymus, parathyroid, face, and teeth. A mouse model carrying a deletion in a functional region of the Tbx1 gene has been extensively used to study anomalies related to this syndrome. We have used the Tbx1 null mouse to understand the tooth phenotype reported in patients afflicted by DiGeorge syndrome. Because of the early lethality of the Tbx1-/- mice, we used long-term culture techniques that allow the unharmed growth of incisors until their full maturity. All cultured incisors of Tbx1-/- mice were hypoplastic and lacked enamel, while thorough histological examinations demonstrated the complete absence of ameloblasts. The absence of enamel is preceded by a decrease in proliferation of the ameloblast precursor cells and a reduction in amelogenin gene expression. The cervical loop area of the incisor, which contains the niche for the epithelial stem cells, was either severely reduced or completely missing in mutant incisors. In contrast, ectopic expression of Tbx1 was observed in incisors from mice with upregulated Fibroblast Growth Factor signalling and was closely linked to ectopic enamel formation and deposition in these incisors. These results demonstrate that Tbx1 is essential for the maintenance of ameloblast progenitor cells in rodent incisors and that its deletion results in the absence of enamel formation.

  3. Postnatal epithelium and mesenchyme stem/progenitor cells in bioengineered amelogenesis and dentinogenesis.

    Science.gov (United States)

    Jiang, Nan; Zhou, Jian; Chen, Mo; Schiff, Michael D; Lee, Chang H; Kong, Kimi; Embree, Mildred C; Zhou, Yanheng; Mao, Jeremy J

    2014-02-01

    Rodent incisors provide a classic model for studying epithelial-mesenchymal interactions in development. However, postnatal stem/progenitor cells in rodent incisors have not been exploited for tooth regeneration. Here, we characterized postnatal rat incisor epithelium and mesenchyme stem/progenitor cells and found that they formed enamel- and dentin-like tissues in vivo. Epithelium and mesenchyme cells were harvested separately from the apical region of postnatal 4-5 day rat incisors. Epithelial and mesenchymal phenotypes were confirmed by immunocytochemistry, CFU assay and/or multi-lineage differentiation. CK14+, Sox2+ and Lgr5+ epithelium stem cells from the cervical loop enhanced amelogenin and ameloblastin expression upon BMP4 or FGF3 stimulation, signifying their differentiation towards ameloblast-like cells, whereas mesenchyme stem/progenitor cells upon BMP4, BMP7 and Wnt3a treatment robustly expressed Dspp, a hallmark of odontoblastic differentiation. We then control-released microencapsulated BMP4, BMP7 and Wnt3a in transplants of epithelium and mesenchyme stem/progenitor cells in the renal capsule of athymic mice in vivo. Enamel and dentin-like tissues were generated in two integrated layers with specific expression of amelogenin and ameloblastin in the newly formed, de novo enamel-like tissue, and DSP in dentin-like tissue. These findings suggest that postnatal epithelium and mesenchyme stem/progenitor cells can be primed towards bioengineered tooth regeneration.

  4. A missense mutation in PIK3R5 gene in a family with ataxia and oculomotor apraxia.

    Science.gov (United States)

    Al Tassan, Nada; Khalil, Dania; Shinwari, Jameela; Al Sharif, Latifa; Bavi, Prashant; Abduljaleel, Zainularifeen; Abu Dhaim, Nada; Magrashi, Amna; Bobis, Steve; Ahmed, Hala; Alahmed, Samaher; Bohlega, Saeed

    2012-02-01

    Autosomal recessive ataxias are heterogeneous group of disorders characterized by cerebellar atrophy and peripheral sensorimotor neuropathy. Molecular characterization of this group of disorders identified a number of genes contributing to these overlapping phenotypes. Ataxia with oculomotor apraxia type 2 (AOA2) is an autosomal recessive form of ataxia caused by mutations in the SETX gene. We report on a consanguineous family with autosomal recessive inheritance and clinical characteristics of AOA2, and no mutations in the SETX gene. We mapped the AOA locus in this family to chromosome 17p12-p13. Sequencing of all genes in the refined region identified a homozygous missense mutation in PIK3R5 that was absent in 477 normal controls. Our characterization of the PIK3R5 protein and findings suggest that it may play a role in the development of the cerebellum and vermis.

  5. Novel compound heterozygous NMNAT1 variants associated with Leber congenital amaurosis

    DEFF Research Database (Denmark)

    Siemiatkowska, Anna M; van den Born, L Ingeborgh; van Genderen, Maria M;

    2014-01-01

    and associated phenotypes in different types of inherited retinal dystrophies. METHODS: DNA samples of 161 patients with LCA without genetic diagnosis were analyzed for variants in NMNAT1 using Sanger sequencing. Variants in exon 5 of NMNAT1, which harbors the majority of the previously identified mutations......, were screened in 532 additional patients with retinal dystrophies. This cohort encompassed 108 persons with isolated or autosomal recessive cone-rod dystrophy (CRD), 271 with isolated or autosomal recessive retinitis pigmentosa (RP), and 49 with autosomal dominant RP, as well as 104 persons with LCA......: Although macular atrophy can occur in LCA and CRD, no NMNAT1 mutations were found in the latter cohort. NMNAT1 variants were also not found in a large group of patients with sporadic or autosomal recessive RP. The enrichment of p.E257K in a heterozygous state in patients with LCA versus controls suggests...

  6. Osteogenesis imperfecta due to compound heterozygosity for the LEPRE1 gene.

    Science.gov (United States)

    Moul, Adrienne; Alladin, Amanda; Navarrete, Cristina; Abdenour, George; Rodriguez, Maria M

    2013-10-01

    Osteogenesis imperfecta is a rare connective tissue disorder characterized by bone fragility and low bone density. Most cases are caused by an autosomal dominant mutation in either COL1A1 or COL1A2 gene encoding type I collagen. However, autosomal recessive forms have been identified. We present a patient with severe respiratory distress due to osteogenesis imperfecta simulating type II, born to a non-consanguineous couple with mixed African-American and African-Hispanic ethnicity. Cultured skin fibroblasts demonstrated compound heterozygosity for mutations in the LEPRE1 gene encoding prolyl 3-hydroxylase 1 confirming the diagnosis of autosomal recessive osteogenesis imperfecta type VIII, perinatal lethal type.

  7. [Partial lipodystrophy in two HLA identical sisters with hypocomplementemia and nephropathy].

    Science.gov (United States)

    Peces, R

    2002-01-01

    Partial lipodystrophy is a rare disorder with both autosomal recessive and familial forms. The cutaneous findings, which are often subtle, consist of gradual loss of subcutaneous fat from the face and upper body. Low levels of C3 and the presence of C3NeF help to identify these patients. Associated systemic abnormalities include the development of membranoproliferative glomerulonephritis, insulin resistance and an increased incidence of autoimmune diseases. We report here two HLA identical sisters with the typical features of partial lipodystrophy associated with recurrent infections, low levels of C3, and nephropathy. Our data suggest an autosomal recessive transmission. We discuss the genetic and molecular basis of this rare association.

  8. CYP7B1

    DEFF Research Database (Denmark)

    Roos, P; Svenstrup, K; Danielsen, E R

    2014-01-01

    UNLABELLED: The SPG5A subtype of Hereditary Spastic Paraplegia (HSP) is a rare autosomal recessive neurodegenerative disorder caused by mutations in the CYP7B1 gene, which encodes a steroid cytochrome P450 7α-hydroxylase. This enzyme provides the primary metabolic route for neurosteroids. Clinica......UNLABELLED: The SPG5A subtype of Hereditary Spastic Paraplegia (HSP) is a rare autosomal recessive neurodegenerative disorder caused by mutations in the CYP7B1 gene, which encodes a steroid cytochrome P450 7α-hydroxylase. This enzyme provides the primary metabolic route for neurosteroids...

  9. [Pyridoxine dependent seizures].

    Science.gov (United States)

    Hansen, K N; Ostergaard, J R; Møller, S M

    1994-10-17

    Pyridoxine dependent seizures is a rare autosomal recessive disorder. Its manifestations are intractable epilepsy leading to death in status epilepticus. Treatment with pyridoxine prevents the seizures and normalizes the EEG. Early diagnosis is important for the intellectual outcome. In Denmark, the disease has occurred in a child of healthy Tamil immigrants, who are first cousins. The child's case story is described and points to awareness of increased occurrence of rare autosomal recessive disorders in immigrants from cultures with traditional consanguinity. We suggest giving a pyridoxine test dosis to all cases of severe epilepsy and status epilepticus in infants younger than 18 months.

  10. KARTAGENER’S SYNDROME

    Directory of Open Access Journals (Sweden)

    Swati M

    2014-11-01

    Full Text Available : BACKGROUND: Kartagener syndrome (a clinical variant of primary ciliary dyskinesia is an autosomal recessive disease characterized by the triad of chronic sinusitis, bronchiectasis and situs inversus with dextrocardia. CASE CHARACTERISTICS: A 11-year-old boy presenting with chronic cough with expectoration requiring frequent nebulisations. OUTCOME: Early diagnosis of this rare congenital autosomal recessive disorder in early life is important in the overall prognosis of the syndrome, as many of the complications can be prevented if timely management is instituted, as was done in this in this case.

  11. Dextrocardia with situs inversus – a case report

    Directory of Open Access Journals (Sweden)

    Radhika D

    2011-05-01

    Full Text Available for undergraduate medical students. It was found that some of visceral organs such as stomach and spleen were located on right side. Liver and gallbladder on left. Both right lung and left lung were bilobed. Heart was flattened directed to right with transposition of great vessels. The report showed that dextrocardia with situs inversus existing in one in ten thousand population. Complete situs inversus may form part of multiple malformational syndromes such as Kartagener syndrome with autosomal recessive transmission, which represent 20-25% cases. Situs inversus is generally autosomal recessive condition although it can be X-linked or found in identical mirror twins.

  12. Fixed Restoration of Amelogenesis Imperfecta%遗传性牙釉质发育不全固定修复

    Institute of Scientific and Technical Information of China (English)

    樊弘毅; 李晓箐; 高姗姗; 卿萍; 于海洋

    2012-01-01

    Objective:To study the characteristics of occlusion in patients with amclogcncsis impcrfecta and to investigate criteria for diagnosing and treating them with the aim of recovering their chewing functions. Methods: A treatment plan was made after complete oral evaluation. Then a transitional prosthesis was applied to the patient for a period (two or three months) of observation. When a proper occlusal position was confirmed, treated patients with fixed prosthesis. Results: Activity of tcm-poromandibular joints were stable and facial appearance was improved significantly. Conclusions: An appropriate design of fixed partial denture* accurate teeth reconstruction, establishment of a proper vertical dimension of occlusion, and the use of transient denture were important for acceptable facial appearance.%目的:研究遗传性牙釉质发育不全患者的咬合关系特点与诊治方法.方法:运用口腔固定修复技术对患者进行咬合重建.确定颌位关系后戴暂时性垫2~3个月,恢复到最适颌位之后行固定义齿修复.结果:患者的颞下颌关节活动稳定,咬合关系基本正常,且固定修复后患者的容貌有明显改观.结论:采用固定修复方法治疗遗传性牙釉质发育不全患者的咬合紊乱,进行咬合重建的效果令人满意.

  13. Localization of the Wilson's disease protein in human liver

    NARCIS (Netherlands)

    Schaefer, M; Roelofsen, H; Wolters, H; Hofmann, WJ; Muller, M; Kuipers, F; Stremmel, W; Vonk, RJ

    1999-01-01

    Background & Aims: Wilson's disease is an autosomal-recessive disorder of copper metabolism that results from the absence or dysfunction of a copper-transporting P-type adenosine triphosphatase that leads to impaired biliary copper excretion and disturbed holoceruloplasmin synthesis, To gain further

  14. Mutation in the AP4M1 Gene Provides a Model for Neuroaxonal Injury in Cerebral Palsy

    NARCIS (Netherlands)

    J.H.M. Verkerk (Annemieke); R. Schot (Rachel); B. Dumee (Belinda); K. Schellekens (Karlijn); S.M.A. Swagemakers (Sigrid); A.M. Bertoli Avella (Aida); M. Leguin (Maarten); J. Dudink (Jeroen); P. Govaert (Paul); A.L. van Zwol (Arjen); J. Hirst (Jennifer); M.W. Wessels (Marja); C.E. Catsman-Berrevoets (Coriene); F.W. Verheijen (Frans); E. de Graaff (Esther); I.F.M. de Coo (René); J.M. Kros (Johan); R. Willemsen (Rob); P.J. Willems (Patrick); P.J. van der Spek (Peter); G.M.S. Mancini (Grazia)

    2009-01-01

    textabstractCerebral palsy due to perinatal injury to cerebral white matter is usually not caused by genetic mutations, but by ischemia and/or inflammation. Here, we describe an autosomal-recessive type of tetraplegic cerebral palsy with mental retardation, reduction of cerebral white matter, and at

  15. Disease: H01117 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available ndrome is a rare, autosomal recessive autoinflammatory disorder consisting of chronic recurrent multifocal o...eal SM, Pelet A, Munnich A, Lyonnet S, Majeed HA, El-Shanti H Homozygous mutations in LPIN2 are responsible for the syndrome of chron...ic recurrent multifocal osteomyelitis and congenital dyserythropoietic anaemia (Majeed syndrome). J Med Genet 42:551-7 (2005) ...

  16. Disease: H00803 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available H00803 Seizures-sensorineural deafness-ataxia-mental retardation-electrolyte imbalance... (SESAME) ; SeSAME/EAST syndrome Seizures-sensorineural deafness-ataxia-mental retardation-electrolyte imbalance...deficit, and electrolyte imbalance. This disease links to autosomal recessive mut

  17. Rud′s syndrome

    Directory of Open Access Journals (Sweden)

    K Pavani

    2014-01-01

    Full Text Available Rud′s syndrome is a rare autosomal recessive hereditary disorder characterized by congenital ichthyosis, epilepsy, dwarfism, sexual infantilism, polyneuritis, and macrocytic anemia. We report here an interesting case of this disorder in an 18-year-old girl for its rarity and academic interest.

  18. RTTN mutations link primary cilia function to organization of the human cerebral cortex

    NARCIS (Netherlands)

    S.K. Kia; E. Verbeek (Elly); M.P. Engelen (Erik); R. Schot (Rachel); R.A. Poot (Raymond); I.F.M. de Coo (René); M. Leguin (Maarten); C.J. Poulton (Cathryn); F. Pourfarzad, F. (Farzin); F.G. Grosveld (Frank); A. Brehm (António); M.C.Y. de Wit (Marie Claire); R. Oegema (Renske); W.B. Dobyns (William); F.W. Verheijen (Frans); G.M.S. Mancini (Grazia)

    2012-01-01

    textabstractPolymicrogyria is a malformation of the developing cerebral cortex caused by abnormal organization and characterized by many small gyri and fusion of the outer molecular layer. We have identified autosomal-recessive mutations in RTTN, encoding Rotatin, in individuals with bilateral diffu

  19. Arterial tortuosity syndrome : Clinical and molecular findings in 12 newly identified families

    NARCIS (Netherlands)

    Callewaert, B. L.; Willaert, A.; Kerstjens-Frederikse, W. S.; De Backer, J.; Devriendt, K.; Albrecht, B.; Ramos-Arroyo, M. A.; Doco-Fenzy, M.; Hennekam, R. C. M.; Pyeritz, R. E.; Krogmann, O. N.; Gillessen-kaesbach, G.; Wakeling, E. L.; Nik-zainal, S.; Francannet, C.; Mauran, P.; Booth, C.; Barrow, M.; Dekens, R.; Loeys, B. L.; Coucke, P. J.; De Paepe, A. M.

    2008-01-01

    Arterial tortuosity syndrome (ATS) is a rare autosomal recessive connective tissue disease, characterized by widespread arterial involvement with elongation, tortuosity, and aneurysms of the large and middle-sized arteries. Recently, SLC2A10 mutations were identified in this condition. This gene enc

  20. Disease: H00593 [KEGG MEDICUS

    Lifescience Database Archive (English)

    Full Text Available 1f of PLEC, leading to disruption of plectin isoform 1f, causes autosomal-recessive limb-girdle muscular dystrophy. Am J Hum Genet 87:834-41 (2010) ... ... Gundesli H, Talim B, Korkusuz P, Balci-Hayta B, Cirak S, Akarsu NA, Topaloglu H, Dincer P Mutation in exon