“The Minnesota Study of Twins Reared Apart” startled scientists by demonstrating that twins reared apart are as alike, across a number of personality traits and other measures, as those raised together, suggesting that genetic influence is pervasive. Dr. Nancy Segal, a professor in the Department of Psychology at California State University, Fullerton, and the director of the Twin Studies Center, offers an overview of the study’s scientific contributions and effect on public consciousness. Dr. Segal is an associate editor of Twin Research and Human Genetics, the official journal of the International Society for Twin Studies.
