A recurrent expansion of a maternal allele with 36 CAG repeats causes Huntington disease in two sisters.
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ABSTRACT:
SUBMITTER: Laccone F
PROVIDER: S-EPMC1288149 | biostudies-literature | 2000 Mar
REPOSITORIES: biostudies-literature
Publications
A recurrent expansion of a maternal allele with 36 CAG repeats causes Huntington disease in two sisters.
American journal of human genetics 20000301 3
Large intergenerational repeat expansions of the CAG trinucleotide repeat in the HD gene have been well documented for the male germline. We describe a recurrent large expansion of a maternal allele with 36 CAG repeats (to 66 and 57 repeats, respectively, in two daughters) associated with onset of Huntington disease (HD) in the second and third decade in a family without history of HD. Our findings give evidence of a gonadal mosaicism in the unaffected mother. We hypothesize that large expansion ...[more]
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