Permit me my skepticism.

First, genetic ancestry tests focus on either the y-chromosome or on mitochondrial DNA. The former represents a line of descent through the male line, the latter the female line. The problem is that you *don't* have two ancestors 1000 years ago. You have hundreds. And most of those ancestors are not traceable using y-chromosome or mitochondrial DNA.

Thus what is scientifically known about the ancestry of Askenazi Jews is very little. We simply do not have the tools to evaluate it very well.

Second, IQ testing is known to be influenced by much more than heredity. Environmental factors matter - such as cultural emphasis of education and valuation of literacy, family size, parental involvement in child education, nutrition, exposure to toxins and diseases. How much of intelligence is heritable is a very large unknown.

My skepticism is screaming alarms. I see people climbing out onto very narrow limbs to draw unwarranted conclusions about heredity - such as William's amusingly-told but unsupported hypothesis that superior intelligence and susceptibility to disease is linked in Jewish populations.

Still, science must show no fear. Hypotheses are allowed, and so is research to confirm or refute them. Perhaps Jews are the beneficiaries of a heritable advantage; learning that's so and discovering the genes responsible could lead to interesting developments for all of humanity. But I'm by no means sanguine that science will deliver us to this particular doorstep.