Familial predisposition to recurrent mutations causing Huntington's disease: genetic risk to sibs of sporadic cases.
J Med Genet
; 30(12): 987-90, 1993 Dec.
Article
em En
| MEDLINE
| ID: mdl-8133509
ABSTRACT
Huntington's disease (HD) is associated with expansion of a CAG repeat in a new gene. We have recently defined a premutation in a paternal allele of 30 to 38 CAG repeats in the HD gene which is greater than that seen in the general population (< 30 repeats) but below the range seen in patients with HD (> 38). These intermediate alleles are unstable during transmission through the germline and in sporadic cases expand to the full mutation associated with the clinical phenotype of HD. Here we have analysed three new mutation families where, in each, the proband and at least one sib have CAG sizes in the HD range. In one of these families, two sibs with expanded CAG repeats are both clinically affected with HD, thus presenting a pseudorecessive pattern of inheritance. In all three families the parental intermediate allele has expanded in more than one offspring, thus showing a previously unrecognised risk of inheriting HD to sibs of sporadic cases of HD.
Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Sequências Repetitivas de Ácido Nucleico
/
Doença de Huntington
/
Mutação
Tipo de estudo:
Etiology_studies
/
Risk_factors_studies
Limite:
Adult
/
Female
/
Humans
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Male
/
Middle aged
Idioma:
En
Revista:
J Med Genet
Ano de publicação:
1993
Tipo de documento:
Article
País de afiliação:
Canadá