I wanted to try to get this thread back on topic, but a cursory search on the Internet for "big boobed chess masters" availed nothing of interest. 
I thought this was funny, but I guess not...
The president of the USA is elected. Blacks can vote. The world chess champion is not elected.
I was going to suggest the same thing as ptoing about the US Presidency, but my angle is a little different. To say that there hasn't been a black world chess champion and then imply that this significantly has something to do with race is almost certainly an underinformed stance. The list of world chess champions is a very short list, like the list of US Presidents. It's not a good idea to try to draw conclusions about genetics from either of those lists, exactly because they are populated by such small numbers of people (small sample size).
If there were literally no black grandmasters anywhere in the whole world, then this might be something worth studying and trying to find out why that is. However, there are black grandmasters. This is extremely important because it very neatly discredits your point. You're obviously trying in some way, however roughly or broadly, to link being black with poor chess playing ability (and by extension, presumably intelligence or logical thinking ability or something generic like that), but at a glance the evidence doesn't appear to support what you're suggesting.
It's similar to what Helm was saying earlier about matriarchal societies existing and how that affects the idea that a patriarchy is inevitable on account of something intrinsic to being human. The fact that there have been matriarchal societies at the very least calls the idea into question and very probably discredits it completely.
From what I know about genes and race, if there is a genetic cause for being good or bad at chess, then my guess is that it has extremely little to do with those few genes that produce racial phenotypes.
