Cri-du-chat syndrome, also called deletion 5p syndrome, (or 5p minus), is a rare genetic disorder. Cri-du-chat syndrome is due to a partial deletion of the short arm of chromosome number 5. The name of this syndrome is French for “cry of the cat,” referring to the distinctive cry of children with this disorder. The cry is caused by abnormal larynx development, which becomes normal within a few weeks of birth. Infants with cri-du-chat have low birth weight and may have respiratory problems. Some people with this disorder have a shortened lifespan, but most have a normal life expectancy.