What causes Down syndrome. Can it be prevented?

[Itisha]

Hello, I am a 16 years old female. Yesterday in our school we organized a book fate where students from various schools came. There were few children who had down syndrome. Can anyone tell me what causes down syndrome in people? Can it be prevented?

[Hitansh]

@itisha Hello, Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome. Human cells normally contain 23 pairs of chromosomes. One chromosome in each pair comes from your father, the other from your mother. Down syndrome results when abnormal cell division involving chromosome 21 occurs. These cell division abnormalities result in an extra partial or full chromosome 21. This extra genetic material is responsible for the characteristic features and developmental problems of Down syndrome. Any one of three genetic variations can cause Down syndrome. Unfortunately, there is no way to prevent Down syndrome.