This edition: Codes Of Life: Behavior Genetics
Mark Newman and Gerald Levey are identical twins, separated at birth. They share the same genes, but were raised by different parents in different environments. Studies of separated twins and adopted siblings are providing insight into the relative impact of genetic and environmental influences, and the extent to which variation among individuals can be attributed to their differing genes. As molecular geneticist Robert Plomin explains, DNA studies are pointing to the fact not one, or five, but hundreds of genes each contribute a small amount of the variance for any one trait.