Family patterns in four dimensions of lateral preference.

Hand, eye, foot, and ear preference were examined in a sample of 459 biologically related parent-offspring triads and 434 sibling pairs. Intercorrelations were computed using the side of preference as the dependent variables and then again using the absolute strength of the displayed preference irrespective of side. The directional analyses did not show strong patterns of familial similarities; however, relatives did tend to resemble each other in the degree of lateralization manifested. Maternal and paternal resemblance to offspring vary over the four indices of laterality, and there are some suggestions of sex-specific interactions. These results imply that genetic influence may operate to affect the degree of expressed preference, while the side of preference may not be genetically encoded. These findings also suggest that lateral preferences for limb and sense organ may not be due to a single causal mechanism.