Chromosomal abnormalities are frequent events. Globally, at least 7.6 million children are born annually with severe genetic or congenital malformations. Precise prevalence data are difficult to collect, especially in India, owing to great diversity of conditions and also because many cases remain undiagnosed. Genetic and congenital abnormality is the second most common cause of infant and childhood mortality and occurs with a prevalence of 25- 60 per 1000 births. The higher prevalence of genetic diseases in a particular community may, however, be due to some social or cultural factors.