Cri du chat syndrome
The syndrome is caused by a bad copying of a gene, which leaves part of chromosome 5p missing about 90% of its material. The condition affects more girls than boys: of six cases on average about one is a boy. What is the effect? The name gives a clue. Children who have it have problems with the voice box. They usually have other disabilities as well: some have a learning disability or physical disability, and others have both of these.