Charles Nydorf <cnydorf@...>
If I remember correctly >from my genetic classes, close cousin
marriage is a two-edged sword. It will tend to keep a gene at a stable
frequency in the community except when, as in the case of Tay-Sachs,
the gene is lethal when inherited >from both parents (the unfortunate
child is homozygous). Homozygotes don't pass on the gene and if there
are enough of them, because of close interbreeding, the gene should
actually grow rarer.
Also if I am not mistaken, diabetes has a multi-genetic
causation and the case that Jews or other populations have a higher
genetic propensity for it has not quite been proved.
Marriage of cousins was quite common and not just in rabbinicalMODERATOR NOTE: Discussions of genetic diseases in general are beyond
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