downs symptoms causes
Down syndrome is caused by abnormal cell division in early embryo development. Normally, a child inherits 46 chromosomes, 23 from each parent. Each chromosome carries DNA, called genes, which tell how the brain and body should develop. But a fetus with Down syndrome has extra or abnormal chromosomes.
Down syndrome (sometimes called Downâs syndrome) is a condition in which a child is born with an extra copy of their 21st chromosome (hence its other name, Trisomy 21). This causes physical and mental developmental delays and disabilities. Many of the disabilities are lifelong and they can also shorten life expectancy.