Attention-Deficit Hyperactivity Disorder Related To Advantageous Gene
Between 10,000 and 40,000 years ago, anthropologists concur that humans were developing the first signs of complex societies, replete with agriculture, rudimentary governments and the creation of cities for the first time. Humans also were rapidly expanding and exploring the planet. These revolutionary changes in human societies may have changed the forces that selected for certain genetic traits.
"Our data show that the creation of the 7R allele was an unusual, spontaneous mutation, which became an advantage for humans," Moyzis said. "Because it was an advantage, the gene became increasingly prevalent. This is very different from other genes that predispose to genetic disorders, where the mutations are detrimental. We believe this helps explain why a disorder with such a strong genetic association is so common today."
The researchers are now working on determining how the genetic variations in DRD4 may actually predispose individuals to ADHD and other behaviors, and on examining the relationship between other complex genetic variations and ADHD.