According to University of California in Irvine scientist, Robert Moyzis, and his collegues, a variant of the dopamine-receptor gene may be associated with longevity. Their findings, published in the Journal of Neuroscience, show that the genetic variant called the dopamine receptor 4 (DRD4) 7-repeat allele, or DRD4 7R allele for short, appears in significantly higher rates in people more than 90 years old.