It affects mental and physical development and can also lead to conditions including heart disease, Alzheimer's disease and leukaemia.According to the UN World Health Organization (WHO), the estimated incidence of Down syndrome is between 1 in 1,000 to 1 in 1,100 live births worldwide; and, each year approximately 3,000 to 5,000 children are born with this chromosome disorder.Mr. Ban said a vicio