Unfortunately, the Maureen Dowd piece about x-celling seems to me to miss the main point of the Duke study about how women have lots more genetic variation from the extra x chromosome than men do.

Dowd frames the findings as legitimating claims about sex differences, going so far as to (sarcastically, I hope) ask whether Larry Summers might have been right about women in science.

What the scientists actually found, though, was unexpected large amounts of variation among women in the particular genes that get expressed from the second x chromosome. The take-home message to me is that variation within sexes in behavior and personality is likely to be (a) larger, and (b) more interesting to study, than variation between women and men. Dowd underplays this point and reinforces the old, tired women-v.-men discourse.

Feminism at its best celebrates women's diversity instead of constructing women as a uniform not-man category. Even with new evidence of variety among women, Dowd's piece chooses to foreground differences between women and men instead of differences among women. The implicit message is that differences among women are only interesting to the extent that they feed the women-v.-men discourse. I think it's a shame that the variety among women part of the story isn't treated as interesting in its own right.

Am I the only person who is uncomfortable with Maureen Dowd's superficial use of unqualified factoids about genetics?

Let me break it down qualitatively:

15% to 20% of the genes in a woman's second X chromosome are expressed. There are about 1000 genes on the X chromosome, therefore, women are expressing about 150 to 200 genes on their second X chromosome

There are 78 genes on the Y chromosome and men express them all. (these genes are unique to men)

Women can express at most about a hundred more genes than men. There might be redundancy between the two X chromosomes which would lower maximum gene expression. (none of these genes are unique to women).

The human genome has somewhere between 20,000 and 25,000 genes. Therefore, an individual woman's gene expression would be at most half a percent greater than a man's.

However, the gene expression within a large population of males is actually going to be greater than the gene expression within a large population of females. In a large population all the genes being expressed in some woman's X will be expressed by some man's X, whereas the Y gene expression, as insignificant as it may be, will not be expressed on any woman's X.

Question - How do you tell an "X" chromosome from a "Y" chromosome?

Answer - Pull down their genes.

I love jokes about the genetic inferiority of groups who think they are superior and seem to run the world. It's great to see them taken down a peg or two. Humour like that is seen as a bit "right-off" in some circles, but I'm glad to see there is no such false "political correctness" on this site. How refreshing!

"Political correctness" means censoring speech because it might offend some people. There is, nonetheless, a substantial difference between finicky political correctness and a reasonable desire for simple, old-fashioned correctness. In that spirit, it frankly bothers me when someone assumes that because some men think they're superior, men throughout the world are deserving of nothing better than to be the subject of Maureen Dowd's misplaced, unscientific accusations of superfluity. Oh, I know you'll claim that I'm only sensitive about it because I know it's true. Whatever. If it's wrong for men to claim categorical superiority - which is most certainly is - then it's also wrong for women to - and it most certainly is.