HANDEDNESS, WITH SPECIAL REFERENCE TO TWINS

Abstract

While the occurrence of right-and left-handedness does not appear to conform to any simple Mendelian formula, the familial incidence of left-handedness rather definitely indicates a genetic basis. Children are more likely to be left-handed if one parent is left-handed, than if both are right-handed (Chamberlain 1928), and in families where both parents are left-handed about 50 percent of the children are also left-handed.