Down syndrome (DS), or Trisomy 21, is defined by an extra copy of chromosome 21 in all cells. In humans there are normally 2
copies of each of 23 chromosomes for a total of 46 in each cell; in DS there are 47.
thernewsreporte
social bookmark : Share diets and weight loss tips
social bookmarking : share news headlines and videos
Monday, September 7, 2009
Subscribe to:
Post Comments (Atom)
No comments:
Post a Comment