Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!tut.cis.ohio-state.edu!ukma!psuvm.bitnet!cunyvm!barilvm!bimacs!kanov From: kanov@bimacs.BITNET (Mechael Kanovsky) Newsgroups: sci.bio Subject: Re: The Ubiquity of Tay-Sachs: a shocking but elegant theory Message-ID: <789@bimacs.BITNET> Date: 12 Feb 89 13:20:34 GMT References: <10276@ut-emx.uucp> Reply-To: kanov@bimacs.UUCP (Mechael Kanovsky) Organization: Bar-Ilan University, Israel. Lines: 24 In article eric@snark.uu.net (Eric S. Raymond) writes: >In <10276@ut-emx.UUCP> ethan@ut-emx.UUCP (Ethan Tecumseh Vishniac) writes: >>Not being a geneticist, I have frequently wondered, but never looked into, >>the question of why an infrequent mutation like Tay-Sachs, which has such >>a devastating effect on those unfortunates who are homozygous for it, has >>such a relatively *high* incidence among Ashkenzaic Jewry (I believe that >>1/30 individuals is heterozygous). > I think that the answer is much simpler. If we take into account that the jews lived in Shtetles i.e. small villages and there was alot of intermarrying like first cousins marrying one another then the chances of the defective gene becoming hozygotis is much higher than in a population where there is a larger gene pool and people marry non-relatives. -- Mechael Kanovsky : BITNET kanov@bimacs.bitnet Math & CS Dept. : UUCP uunet!mcvax!humus!bimacs!kanov Bar-Ilan University : ARPA kanov%bimacs.bitnet@cunyvm.cuny.edu Ramat-Gan Israel : CSNET kanov%bimacs.bitnet%cunyvm.cuny.edu@csnet-relay ! You can't propel yourself forward ! ! by patting yourself on the back !