Genenic Tests May Reveal Incestuous Family History - ABC News

Genenic Tests May Reveal Incestuous Family History - ABC News: "At Baylor College of Medicine in Houston, sophisticated DNA analyses used to diagnose such disabilities as birth defects, epilepsy or developmental delays revealed that in some children, about 25 percent of genetic material inherited from their mother was the same as material inherited from their father. That suggested their parents were first-degree relatives -- father and daughter, brother and sister, or mother and son. Children who inherited half as much identical DNA from both parents likely were the offspring of second-degree relatives, such as an uncle and niece. Had the mothers and fathers of these youngsters been unrelated, those same stretches of DNA would have differed."