Cri-du-chat syndrome What is cri-du-chat syndrome? Cri-du-chat (cat's cry) syndrome, also known as 5p- (5p minus) syndrome, is a chromosomal condition that results when a piece of chromosome 5 is missing. Infants with this condition often have a high-pitched cry that sounds like that of a cat. The disorder is characterized by intellectual disability and delayed development, small head size (microcephaly), low birth weight, and weak muscle tone (hypotonia) in infancy. Affected individuals also have distinctive facial features, including widely set eyes (hypertelorism), low-set ears, a small jaw, and a rounded face. Some children with cri-du-chat syndrome are born with a heart defect. How common is cri-du-chat syndrome? Cri-du-chat syndrome occurs in an estimated 1 in 20,000 to 50,000 newborns. This condition is found in people of all ethnic backgrounds. What are the genetic changes related to cri-du-chat syndrome? Cri-du-chat syndrome is caused by a deletion of the end of the short (p) arm of chromosome 5. This chromosomal change is written as 5p-. The size of the deletion varies among affected individuals; studies suggest that larger deletions tend to result in more severe intellectual disability and developmental delay than smaller deletions. The signs and symptoms of cri-du-chat syndrome are probably related to the loss of multiple genes on the short arm of chromosome 5. Researchers believe that the loss of a specific gene, CTNND2, is associated with severe intellectual disability in some people with this condition. They are working to determine how the loss of other genes in this region contributes to the characteristic features of cri-du-chat syndrome. Can cri-du-chat syndrome be inherited? Most cases of cri-du-chat syndrome are not inherited. The deletion occurs most often as a random event during the formation of reproductive cells (eggs or sperm) or in early fetal development. Affected people typically have no history of the disorder in their family. About 10 percent of people with cri-du-chat syndrome inherit the chromosome abnormality from an unaffected parent. In these cases, the parent carries a chromosomal rearrangement called a balanced translocation, in which no genetic material is gained or lost. Balanced translocations usually do not cause any health problems; however, they can become unbalanced as they are passed to the next generation. Children who inherit an unbalanced translocation can have a chromosomal rearrangement with extra or missing genetic material. Individuals with cri-du-chat syndrome who inherit an unbalanced translocation are missing genetic material from the short arm of chromosome 5, which results in the intellectual disability and health problems characteristic of this disorder. Where can I find information about diagnosis or management of cri-du-chat syndrome? These resources address the diagnosis or management of cri-du-chat syndrome and may include treatment providers. Genetic Testing Registry: 5p partial monosomy syndrome MedlinePlus Encyclopedia: Cri du Chat Syndrome You might also find information on the diagnosis or management of cri-du-chat syndrome in Educational resources and Patient support. General information about the diagnosis and management of genetic conditions is available in the Handbook. Read more about genetic testing, particularly the difference between clinical tests and research tests. To locate a healthcare provider, see How can I find a genetics professional in my area? in the Handbook. Where can I find additional information about cri-du-chat syndrome? You may find the following resources about cri-du-chat syndrome helpful. These materials are written for the general public. MedlinePlus - Health information  Genetic and Rare Diseases Information Center- Information about genetic conditions and rare diseases Additional NIH Resources - National Institutes of Health National Human Genome Research Institute Educational resources - Information pages Patient support - For patients and families  What other names do people use for cri-du-chat syndrome? cat cry syndrome chromosome 5p- Syndrome 5p deletion syndrome monosomy 5p 5p- syndrome Where can I find general information about genetic conditions? The Handbook provides basic information about genetics in clear language. What does it mean if a disorder seems to run in my family? What is a chromosome? Can changes in the number of chromosomes affect health and development? Are chromosomal disorders inherited? These links provide additional genetics resources that may be useful. Genetics and health Resources for Patients and Families Resources for Health Professionals The resources on this site should not be used as a substitute for professional medical care or advice. Shailesh kr shukla  directoratace@gmail.com