RESUMO
Ambras syndrome (AMS) is a unique form of universal congenital hypertrichosis. In patients with this syndrome, the whole body is covered with fine long hair, except for areas where normally no hair grows. There is accompanying facial dysmorphism and teeth abnormalities, including retarded first and second dentition and absence of teeth. In 1993, Baumeister et al. reported an isolated case of Ambras syndrome in association with a pericentric inversion of chromosome 8. Subsequently, another patient with congenital hypertrichosis and rearrangement of chromosome 8 was reported by Balducci et al. (1998). Both of these patients have a breakpoint in 8q22 in common suggesting that this region of chromosome 8 contains a gene involved in regulation of hair growth. In order to precisely determine the nature of the rearrangement in the case of Ambras syndrome, we have used fluorescent in situ hybridization (FISH) analysis. We have cloned the inversion breakpoints in this patient and generated a detailed physical map of the inversion breakpoint interval. Analysis of the transcripts that map in the vicinity of the breakpoints revealed that the inversion does not disrupt a gene, and suggests that the phenotype is caused by a position effect.
Assuntos
Anormalidades Múltiplas/genética , Quebra Cromossômica/genética , Inversão Cromossômica/genética , Cromossomos Humanos Par 8/genética , Clonagem Molecular/métodos , Assimetria Facial/genética , Hipertricose/genética , Anormalidades Dentárias/genética , Feminino , Humanos , Recém-Nascido , SíndromeRESUMO
Research into the field of skin biology has grown exponentially over the past two decades. Even though the fundamental molecular pathways are still not fully understood, there have been significant advances in our understanding of the underlying mechanisms involved in the pathogenesis of genodermatosis. The cloning of many candidate genes involved in the etiology of skin diseases has been facilitated by initial cytogenetic evidence. This review will synthesize recent findings that led to the discovery of candidate genes for anhidrotic ectodermal dysplasia, Williams-Beuren syndrome, neurofibromatosis-I and tricho-rhino-phalangeal syndrome.
Assuntos
Citogenética/métodos , Predisposição Genética para Doença/genética , Dermatopatias/genética , Displasia Ectodérmica/genética , Ectodisplasinas , Humanos , Síndrome de Langer-Giedion/genética , Proteínas de Membrana/genética , Neurofibromatose 1/genética , Neurofibromina 1 , Transdução de Sinais/genética , Síndrome de Williams/genéticaRESUMO
We report a large Mexican kindred with a variant form of congenital universal hypertrichosis that is inherited in an apparent X-linked recessive manner. In addition to the generalized hypertrichosis, the affected individuals have dental malformations and deafness. Males are more severely affected than females who exhibit only mild hypertrichosis, but not deafness or dental anomalies. Haplotype analysis in this pedigree revealed linkage to a 13-cM region on chromosome Xq24-q27.1 between markers GATA198A10 and DXS8106. Localization of the gene underlying this form of hypertrichosis is the initial step in identifying genes on the X chromosome that are involved in the control of hair growth and development.
Assuntos
Cromossomos Humanos X , Surdez/genética , Ligação Genética , Hipertricose/congênito , Hipertricose/genética , Anormalidades Dentárias/genética , Mapeamento Cromossômico , Análise Mutacional de DNA , Feminino , Genes Recessivos , Genótipo , Haplótipos , Humanos , Masculino , México , Linhagem , FenótipoRESUMO
We report the clinical and molecular findings in a patient with a mild form of recessive dystrophic epidermolysis bullosa and aortic insufficiency. To our knowledge, this is the first report of association between dystrophic epidermolysis bullosa and abnormalities of the aortic valve. Analysis of the COL7A1 gene has revealed two new mutations, a 20-bp duplication and a splice site mutation.