There are three different types of Down Syndrome. These types are trisomy 21, mosaicism, and translocation.
1. Trisomy 21 is called nondisjunction which is an error in cell division and accounts for 95% of Down Syndrome cases.
2. Mosaicism happens when an error in cell division of chromosome 21 takes place in one of the cell divisions. This type accounts for 1% of cases and the characteristics of Down Syndrome are less than the other two types of Down Syndrome.
3. Translocation occurs when part of chromosome 21 breaks off during cell division and accounts for 4% of Down Syndrome cases.