Aneuploidy
Aneuploidy refers to an abnormal number of chromosomes. There may be extra or missing chromosomes. Apart from red blood cells and gametes, all human cells have 23 pairs of chromosomes (total = 46). The first 22 pairs are called the autosomes, and the 23rd pair is the sex chromosomes.
The most common aneuploidies that survive are:-
The most common aneuploidies that survive are:-
- Trisomy 21 (Down's syndrome) - 1 in 800 births
- Trisomy 18 (Edwards syndrome) - 1 in 6000 births
- Trisomy 13 (Patau syndrome) - 1 in 10,000 births
