Inheritance of hypoplastic left heart syndrome (HLHS): further observations.

From a survey of newborn infants using truncate ascertainment of families through affected offspring, 64 cases of hypoplastic left heart syndrome (HLHS) were found. Pedigree information was obtained from 42 families. The incidence of HLHS, based on 64 affected infants, was 36.5/100,000 births. The incidence of HLHS with aortic and/or mitral atresia was 25.1/100,000 births. The recurrence among later siblings was about 2 %. Autosomal recessive hypothesis of transmission of this disorder was not supported. Using Edwards' formula, the observed recurrence among later siblings was compatible with polygenic inheritance.