Chromosomal Aneuploidy, Mosaicism and Eugenics

Abstract

SummaryChromosomal aneuploidy in individuals is very frequent, and is generally a sporadic occurrence. Some aneuploidies seem to be familial, however; that is, parents may have more than one aneuploid child, or they may come from families in which an agglomeration of aneuploidies is distributed over several generations. Since, in such instances, parents often seek eugenic counsel to learn their chances of having aneuploid children, four types of familial aneuploidy and their recurrence risks are described. Special emphasis is given to the more important types of familial interchange, for which the recurrence risks can be calculated with fair accuracy. Familial mosaicism, a rare and puzzling genetic entity with which aneuploidy seems definitely correlated, is discussed.