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Braz. J. Genet. vol.19 no.4 Ribeirão Preto 1996
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Maternal age and Down syndrome in Southeastern Brazil
Bernardo BeiguelmanI; Henrique KriegerII; Luciana Marques da SilvaI
IDepartamento de Genética Médica, Faculdade de Ciências Médicas, Universidade Estadual de Campinas (UNICAMP), Caixa Postal 6111,13081-970 Campinas, SP, Brasil. Send correspondence to B.B.
IIDepartamento de Parasitologia, Instituto de Ciências Biomédicas, USP, São Paulo, SP, Brasil
The proportion of maternal-age-independent patients estimated among 200 Brazilian Down syndrome children (59.6%) was significantly larger than that of maternal-age-dependent cases (40.4%). The latter proportion is the smallest observed in pertinent literature and due basically to the low mean maternal age of the population analyzed. Based on the remarkable correlation (r = 0.95) between the proportion of maternal-age-dependent patients and the mean maternal age of the general population, a simple predictive equation to estimate the proportion of maternal-age-dependent Down syndrome patients based on the mean maternal age of the general population is suggested in situations where reliable data on the incidence of this syndrome according to maternal age is not available.
Keywords: maternal age; Down syndrome; Southeastern Brazil.
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