Genetic inheritance of the brain

[IvoryTowerDenizen]

@ZenBeam

Large patches is what I expected from looking at the Calico cat image in the article. But that doesn’t square with IvoryTowerDenizen’s post that

With large patches, the two eyes might be different from each other, but I wouldn’t expect multiple patches in a single retina. Do you (or anyone) have a source for the typical size of this X-chromosome inactivation mosaicism in humans?

It will depend on the tissue and the number of times the cells divide. Skin cells divide a lot so a single cell will give rise to a large number of generations of progeny cells, each bearing the same inactivated X. The patch, then, will be very large. Retinal cells divide much fewer times, so the patches are very small.

[eschereal]

My question would be, to what extent do genetics affect intelligence? The approach to raising children differs WRT girls v. boys, so how they perform on “IQ tests” may at least partially be a cultural affect.

The brain, after all, is a profoundly dynamic organ in humans. That is one of the things that makes us unusual/unique amongst animals. Early development is quite important, the way we relate to children on a gender basis may be significantly skewing the data. In fact, some of the cognitive differences between men and women may be developmental adaptation rather than purely biologically driven.

We are almost treating genetics like some kind of deity, that seems like a bad plan to me.

[IvoryTowerDenizen]

@eschereal

My question would be, to what extent do genetics affect intelligence? The approach to raising children differs WRT girls v. boys, so how they perform on “IQ tests” may at least partially be a cultural affect.

The brain, after all, is a profoundly dynamic organ in humans. That is one of the things that makes us unusual/unique amongst animals. Early development is quite important, the way we relate to children on a gender basis may be significantly skewing the data. In fact, some of the cognitive differences between men and women may be developmental adaptation rather than purely biologically driven.

We are almost treating genetics like some kind of deity, that seems like a bad plan to me.

Very few geneticists would dispute any of what you’re saying.

[Smeghead]

@eschereal

My question would be, to what extent do genetics affect intelligence? The approach to raising children differs WRT girls v. boys, so how they perform on “IQ tests” may at least partially be a cultural affect.

The brain, after all, is a profoundly dynamic organ in humans. That is one of the things that makes us unusual/unique amongst animals. Early development is quite important, the way we relate to children on a gender basis may be significantly skewing the data. In fact, some of the cognitive differences between men and women may be developmental adaptation rather than purely biologically driven.

We are almost treating genetics like some kind of deity, that seems like a bad plan to me.

This is why the author’s hypothesis would be exceedingly difficult to test. You’d need to have a totally objective, reliable, reproducible measure of cognitive performance that is entirely resistant to nongenetic factors. First one to come up with one wins a prize. And probably a free trip to Stockholm.