Familial Effects in Schizophrenia and Homosexuality

Abstract

This paper begins by reviewing the problem of determining whether there is a genetic factor in schizophrenia and homosexuality by considering the problem explaining the resulting apparently stationary polymorphisms. By analysing unpublished data on homosexuals it is concluded that the latter can not be explained by a genetic factor. The implications of the observed increases in parental age and parental loss in these diseases are then discussed, together with their implications for the genetic hypotheses.