Were it not for a single base pair insertion/deletion mutation in the
"Our analyses show how positive natural selection can shape variation in a human population, because we exclude other possibilities, said lead author Matt Rockman, of Duke University. "For a long time, it's been argued that genetic variation underlying disease is the result of deleterious mutations. That is, there's a 'good' version of the gene but occasionally a 'bad' mutation arises that leads to disease susceptibility."
"However, what we find in the case of