The survival of the human species in the face of high rates of genetic mutations has remained an important problem in evolutionary biology. While mutations provide a source of novelty for the species, a large fraction of these genetic changes can also be damaging. A newborn human is estimated to have ~70 new mutations that the parents did not have. In a project conducted by Brigham and Women’s Hospital research geneticist Shamil Sunyaev, PhD, and University of Michigan professor Alexey Kondrashov, PhD, scientists studied natural selection in humans.