International Journal of Cardiology, 27 (1990) 175-178 Elsevier 175 CARD10 01060 Down’s syndrome: different distribution of congenital heart diseases between the sexes Fhtima F. Pinto I, Luis Nunes *, Fernando Ferraz * and Fernanda Sampayo ’ ’ Department of Paediatric Cardiologv of the Hospital of “Santa Marta”, Lisbon, Portugal; ’ Department of Genetics of the Hospital of “Dona Estefznia”, Lisbon, Portugal (Received 26 September 1989; revision accepted 4 January 1990) Pinto FF, Nunes L, Ferraz F, Sampayo F. Down’s syndrome: different distribution of congenital heart diseases between the sexes. Int J Cardiol 1990;27:175-178. zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIH We have investigated the reasons why female patients with Down’s syndrome prevail in our out-patient clinic for Paediatric Cardiology compared to the higher incidence of Down’s syndrome among live born male children. We reviewed 277 cases of Down’s syndrome, 119 males (42.%%) and 158 females (57.04%) from 1970 to 1987. A final diagnosis of the type of the congenital heart disease was accomplished among 210 cases, 85 males (40.47%) and 125 females (59.38%). This different distribution between the sexes was significant (P < 0.01) when compared to that of the general population with congenital heart disease (4150 patients, 2108 males and 2042 females). The dominant lesion was atrioventricular septal defect, (130 cases; 46 males [54.11%] and 84 females (67.2oo/o]). We found an identical incidence of this lesion among patients without Down’s syndrome. In the studied population, we did not find any of the congenital heart diseases usually prevalent in males, such as aortic coarctation or stenosis and complete transposition. The molecular determinants of Down’s syndrome seem to influence the preponderance of atrioventricular septal defect in females, increasing its incidence, while seeming to act in a negative way concerning congenital heart diseases usually showing male prevalence. Key words: Congenital heart disease; Down’s syndrome; Genetics Introduction Down’s syndrome was described for the first time in 1866 by John Langdon Down [l], and its association with trisomy of the 21st chromosome was subsequently demonstrated in 1959 by Lejeune [2]. It was in 1960 and 1961 that Polani and Clarke [3,4] described the association with chro- mosomal translocation and mosaicism. The syn- drome has a relatively constant phenotype which is associated with mental retardation. The craneo- facial dysmorphism is typical, although there are Correspondence to: F.F. Pinto, MD. Serviqo de Cardiologia Pediltrica, Hospital de Santa Marta, Rua de Santa Marta, 1100 Lisboa. Portugal. no pathognomonic signs. The diagnosis is almost always obvious, but it must always be confirmed by karyotypic analysis. Infants and children with 0167-5273/90/$03.50 0 1990 Elsevier Science Publishers B.V. (Biomedical Division)