"Cri-du-chat" means in French "CRy of the cat" referring to the distinctive cry of the children with this disorder. It is a chromosomal condition that results when a piece of chromosome 5 is missing and it is difficult to diagnose for children above 2 years old because the symptoms are no intense. Cri-du-chat is caused by a deletion (the length of which may vary) on the short arm of chromosome 5. Multiple genes are lost during this deletion and one of the most important missing gene is called TERT (telomerase reverse transcriptase) which is important for cell division.
There is no specific treatment for this disorder and the parents of the child help it to reach its maximum potential.
Approximately 80% of cases are attributed to autogenous deletion, in one of the two chromosomes 10 to 13% by wrong registration, and the rest 7-10% are the result of rare genetic disorders.
Characteristics except for the head which is the most common may include feeding difficulties, delays in walking, hyperactivity, scoliosis, and significant retardation. A small number of children are born with serious organ defects and other life-threatening medical conditions, although most individuals with cri du chat syndrome have a normal life expectancy.