(See also Overview of Chromosome Disorders.)
Cri-du-chat syndrome is a rare syndrome in which part of chromosome 5 is missing. The size of the missing part varies, and people who have larger deletions are often more severely affected.
Symptoms of cri-du-chat syndrome often include a characteristic high-pitched, mewing cry that sounds like a kitten crying. This cry may be heard immediately after birth, lasts several weeks, and then disappears. However, not all affected newborns have this distinct cry. An infant with this syndrome may have a low birth weight and a small head with many abnormal features, including a round face, small jaw, wide nose, widely separated eyes, crossed eyes (strabismus), and abnormally shaped ears set low in the head. Often the infant seems limp. Webbed fingers and toes (syndactyly) and heart defects are common. There are significant limitations in mental and physical development. Many children with cri du chat syndrome survive to adulthood but have substantial disabilities.