The relationship between legal abortion and marriage

Abstract

Tay‐Sachs disease is a recessively inherited, invariably lethal, degenerative neurological disorder caused by a lack of hexoaminidase‐A. It is a hundred times more prevalent among the American‐born descendants of the East European Ashkenazim Jews than among any other people in the world. The present retrospective study demonstrates that the currently observed increased gene frequency among these formerly endogamous, highly fecund people is most probably a result of genetic drift. Unique and drastic population contractive and expansion phases are documented to deduce the formation of numerous founder populations which were scattered throughout Eastern Europe by the nineteenth century. The subsequent mass familial migrations to the United States, coupled with the cultural practices of the immigrant generation, greatly enhanced the chances for heterozygote carriers to marry each other. Even if some form of selection were operative in the past, the concatenation of unique cultural events provides convincing evidence for the acceptance of drift as the primary cause for the differential gene frequency.