Genetic aspects of congenital heart disease in down syndrome

Congenital heart disease (CHD) is a major factor in increased mortality in infancy and childhood. The aim of this study was to determine the frequency of chromosomal abnormalities in Down syndrome (DS) children is important in understanding the etiology of congenital malformations. Down syndrome also called Trisomy 21, is a condition in which extra genetic material causes delays in the way a child develops, both mentally and physically and also is a major cause of congenital heart disease and the most frequent known cause of atrioventricular septal defects (AVSD). Twenty four cases of Down's syndrome were found among 160 children with congenital heart disease under the age of 1day to 14 years, of which 14(58.3%) were males and 10(41.6%) were females, while the remaining 26(16.2%) cases had normal karyotype, Among 74(46.2%) cases with multiple system malformations and 36(22.5%) cases with known and unknown congenital defects. Consanguinity was observed in normal karyotype 30(75%) and abnormal karyotype 10(25%) results in CHD patients. Down syndrome is usually identified soon after birth by a characteristic pattern of dysmorphic features. The diagnosis is confirmed by karyotype analysis and also this study was undertaken to obtain more information about the nature of heart defects associated with Down's syndrome.