title: Tay-Sachs disease in Brazilian patients: prevalence of the IVS7+1g>c mutation.
abstract: Seven Brazilian Tay-Sachs disease cases were screened for the most frequent causative mutations. They all presented at least one copy of the IVS7+1g>c mutation. Three patients were homozygotes, three were compound heterozygotes, and in one case only the mother was tested and shown to carry the IVS7+1g>c mutation. In the second allele the compound heterozygotes presented: R178H (the DN allele), InsTATC1278 and an unidentified mutation. The IVS7+1g>c mutation has already been described in three Portuguese patients. In this study, all families were unaware of any Portuguese ancestry. Since Brazil was a Portuguese colony, the mutation most probably came from ancient common ancestry. The initial molecular analysis of Tay-Sachs disease patients in Brazil indicated a prevalence of the IVS7+1g>c mutation, possibly as a result of genetic drift.
authors.affiliation: Centro de Estudos do Genoma Humano, Depto de Genética, Instituto de Biociências, Universidade de São Paulo, Brazil.
authors.forename: R
authors.initials: R
authors.lastname: Rozenberg
authors.forename: A M
authors.initials: AM
authors.lastname: Martins
authors.forename: C
authors.initials: C
authors.lastname: Micheletti
authors.forename: Z
authors.initials: Z
authors.lastname: Mustacchi
authors.forename: L V
authors.initials: LV
authors.lastname: Pereira
mesh_terms: D001938:Brazil; D005787:Gene Frequency; D006579:Heterozygote; D006720:Homozygote; D006801:Humans; D007438:Introns / Q000235:genetics; D009154:Mutation; D011174:Portugal / Q000208:ethnology; D013661:Tay-Sachs Disease / Q000235:genetics*