What if it’s true that staying active does not give us a few more years, as some researchers suggest? What if, just by coincidence, the same gene that tends to make people active also makes them live a little longer? That’s the hypothesis of researchers at the University of California in Irvine, who have learned that a dopamine-receptor gene – called the DRD4 7R allele – appears in significantly higher rates in people more than 90 years old. One other thing about that gene: people who carry it seem to be more motivated to pursue social, intellectual and physical activities. The Irvine study analyzed genetic samples from 310 people in a study of people over 90 years old, and found that the “oldest-old” population had a 66 percent increase in people carrying the variant relative to a control group of 2,902 people between the ages of 7 and 45. The variant also was strongly correlated with higher levels of physical activity. Read more from UC Irvine.