how do people get down syndrome? what does it do?

Question: how do people get down syndrome? what does it do?

Asked by microcoolio to Darren, Deuan, Duncan, Lori-An, Michelle on 22 Jun 2010 in Categories: General.
- Michelle Hudson-Shore answered on 21 Jun 2010:
  
  Down Syndrome is caused when someone has an extra copy of chromosome 21 when they are born. The effects of the extra genetic material vary from mild problems to more severe disability and health problems. For more information have a look at Down Syndrome online at http://www.down-syndrome.org/ or one of the other Down syndrome associations.
- Darren Nesbeth answered on 21 Jun 2010:
  
  I thinks they have an extra chromosome by mistake. It causes system-wide problems.
- Lori-An Etherington answered on 22 Jun 2010:
  
  Normally, at the time of conception a baby inherits genetic information from its parents in the form of 46 chromosomes (23 from the mother and 23 from the father). However in Down syndrome, a child gets an extra chromosome 21, it is unclear why this happens, although women over 35 have a higher risk of having a baby with Down syndrome. This additional genetic material results in the characteristic physical features and developmental delays that are seen in Down syndrome.

Question: how do people get down syndrome? what does it do?