- Cri-du-chat is one of the most common syndromes caused by a chromosomal deletion. It affects between 1 in 20,000 and 1 in 50,000 babies.
- In 80 percent of the cases, the chromosome carrying the deletion comes from the father's sperm rather than the mother's egg.
- The geneticist Jerome Lejeune identified cri-du-chat syndrome in 1963. He also discovered the genetic abnormality that causes Down syndrome.