Patent ductus arteriosus. Study of two families

Patent ductus arteriosus (PDA) has been found in several members in consecutive generations of two families. In one family the proband's father had affected children through two matings with unrelated wives. In both families, operation confirmed the PDA in each case in two generations. However, in the second family, a maternal great aunt of the proband had characteristic clinical findings, thus making three generations affected. This sequence is best explained by autosomal dominant inheritance with a high degree of specificity. Two other mechanisms for production of PDA seem well established by other studies: (1) maternal rubella and (2) a recessive characteristic. Further family studies are needed to clarify the exact mode of inheritance.