Is Down syndrome inherited?
- The two most common forms of Down syndrome, Trisomy 21 and Mosaic, which make up approximately 96% of cases, are not inherited.
- Robertsonian/Translocation Down syndrome can be inherited but it can also be spontaneous.
- The chance of having another baby with Down syndrome is very small, only slightly higher than usual.
- Other family members (the baby’s siblings, aunts and cousins) do not have an increased chance of having a baby with Down syndrome.
- Very few people with Down syndrome have been known to have children. If they do have children, the chance of them having a baby with Down syndrome is high.