Fascinating article in The New York Times about genetics and neuroscience. One of the most bizarre things though is how the article concludes:

Dr. Walsh's success is partly a result of his research strategy: he has focused on populations and regions, like the Middle East, where the deformities are more easily found because families are large, marriage among close relatives is common and the people stay in the same villages or cities for generations.

In Riyadh, Saudi Arabia, for example, 58 percent of women marry blood relatives, Dr. Walsh said, so researchers need to find only 10 affected families to have enough cases to study instead of the thousands of families that would otherwise be required.