Study of the origin of nondisjunction in a family with two cases of Down syndrome using cytogenetic and molecular polymorphisms

This is the authors' abstract. We don't add key points for this paper.

We analyzed the possibility of inherited predisposition to nondisjunction in a family with two cases of Down syndrome using restriction fragment length polymorphisms and cytogenetic heteromorphisms. In both patients the extra chromosome 21 was the result of a nondisjunction event at first meiotic division in the mother. Since both patients are maternally related, genetic predisposition cannot be excluded in this family.