Chromosome studies in 156 patients with congenital heart disease.

Abnormal chromosomes are present in Down's syndrome, where the incidence of congenital heart disease varies from 22 to 38 per cent (Kaiser and Schmid, 1952; Rowe and Uchida, 1961) and in Turner's syndrome, which may be complicated by coarctation of the aorta (Polani, Hunter, aild Lennox, 1954) and pulmonary valve stenosis (Rainier-Pope et al., 1964). In the rare trisomic syndromes involving chromosomes 13-15 and 17-18 the frequency of ventricular septal defect and persistent ductus arteriosus has been noted (Townes et al., 1963; Smith et al., 1963). In addition persistent ductus arteriosus was found in 3 of the 10 cases of XXXXY sex chromosomes reviewed by Joseph, Anders, and Taylor (1964). Chromosome abnormalities have also been reported in patients with uncomplicated atrial septal defects and other forms of congenital heart disease (Book, Santesson, and Zetterqvist, 1961; Sasaki, Makino, and Kajii, 1963). It was this background that prompted us to examine the chromosomes in patients with isolated congenital heart disease. Cases in which the cardiac lesion was associated with Down's and Turner's syndromes were excluded as the cytogenetic abnormalities of these syndromes have already been described.