Cri du chat syndrome is a rare genetic disorder caused by a missing section on chromosome 5, or sometimes by material from another chromosome being missing as well. The disorder is not caused by anything the parents have done. The missing genetic material can occur randomly during the development of the egg or sperm, or a small number of cases occur when a parent passes a different, rearranged form of the chromosome to their child. The size of the deletion varies among affected individuals, and larger deletions tend to result in more severe intellectual disability and developmental delay than smaller deletions.

Symptoms of cri du chat syndrome can vary widely, but some common ones include a high-pitched cry that sounds like a cat, intellectual disability, delayed development, small head size (microcephaly), widely set eyes (hypertelorism), low-set ears, a small jaw, and a rounded face. Other symptoms may include feeding difficulties, delays in walking, hyperactivity, scoliosis, and significant disability. Children with cri du chat syndrome commonly experience health problems including difficulties with suckling and swallowing, gastric reflux, constipation, high rate of infections, poor muscle tone, eye problems, and heart and kidney problems.

Cri du chat syndrome is diagnosed by a health care provider who notes the clinical symptoms associated with the condition, and the cat-like cry is the most common symptom. Genetic tests can show a missing part of chromosome 5, and skull x-rays may reveal any problems with the shape of the base.

In summary, cri du chat syndrome is a rare genetic disorder caused by a missing section on chromosome 5, and it is not caused by anything the parents have done. The missing genetic material can occur randomly during the development of the egg or sperm, or a small number of cases occur when a parent passes a different, rearranged form of the chromosome to their child. Symptoms of cri du chat syndrome can vary widely, but some common ones include a high-pitched cry that sounds like a cat, intellectual disability, delayed development, small head size, widely set eyes, low-set ears, a small jaw, and a rounded face. Children with cri du chat syndrome commonly experience health problems including difficulties with suckling and swallowing, gastric reflux, constipation, high rate of infections, poor muscle tone, eye problems, and heart and kidney problems. Cri du chat syndrome is diagnosed by a health care provider who notes the clinical symptoms associated with the condition, and genetic tests can show a missing part of chromosom...