Cri+du+Chat+Syndrome

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=Cri Du Chat Syndrome  =

What is Cri Du Chat Syndrome?
Cri Du Chat Syndrome is a group of symptoms the result in the loss of a piece of chromosome #5. It is a rare genetic disorder found in people of all ethnic backgrounds, and is more common in females by a 3:2 ratio. There does not appear to be any geographical location where cri du chat is more common. Jerome Lejeune was the first person to discover Cri Du Chat Syndome and the disorder affects 1 in 20,000 to 50,000 live births. The cry of an infant who has this disorder is high-pitched and sounds like a cat. (1,2) 

Symptoms
•   High-pitched cry that sounds like a cat. • Downward slant to the eyes. • Weight at birth is low and the baby's growth process is slow. • Abnormally shaped ears. • Mental retardation. • Sometimes webbing of the fingers or toes.     • Single line in the palm of the hand. (simian crease)                (4) • Hanging skin just in front of the ears. (skin tags) • Slow or incomplete development of basic skills. • Small head. (microephaly) • Small jaw. (micrognathia) • Wide-set eyes                             (3)

(5)               (6)

Treatment/Help
There is no specific treatment available for this disorder so medical care is focused on the symptoms. Parents of a child with this syndrome should have genetic counseling and a karyotype test. Physical therapy is recommended to strengthen the muscles. To increase communication skills, a speech therapist can help the child learn to use sign language. The child may need a gastrostmy tube for feeding. About 1/3 of infants lose the cat-like cry at age 2. (3)

Causes/Risks
Cri Du Chat Syndrome is a rare genetic disorder. It is caused by a break in the DNA molecule that makes up chromosome 5 is missing as shown in the picture below. In about 80% of patients the defective chromosome comes the father. An abnormal larynax (organ in the neck) causes the cat-like cry made by infants.  Most cases occur when there is a deletion in chromosome 5 during the development in the egg or sperm. One deleted gene called TERT (telomerase reverse transciptase) is involved in the control of cell growth and is said to be an part of how the features develop. <span style="background-color: rgb(255, 255, 255);">(3)

(2)

Prevention
There is no known prevention for cri du chat syndrome. It may be a good idea for couples that have had family members with the disorder in the past to consider genetic counseling before they have a baby.(3)

Prognosis/Outlook
Most cri du chat patients suffer from mental retardation. Half of the children learn enough verbal skills to communicate. The cat-like cry also becomes less noticable over time. The life span is very low. 90% of infants die before their first birthday. Three patients, however, have lived past their fifties, and the oldest patient ever with cri du chat syndrome is 60. <span style="background-color: rgb(245, 10, 10);"><span style="background-color: rgb(255, 255, 255);"> <span style="background-color: rgb(255, 255, 255);">    (9)

Punnet Square
The deletion that causes cri du chat syndrome is caused by a dominant trait. This trait does not provide any advantage for the patient. The ctnnd2 gene is the primary gene in patients that is affected by cri du chat syndrome. The gene usually makes the delta catenin protein. The delta catenin protein works in the nerve system and helps cells stick together and helps cell movement. The gene is deleted in cri du chat and the protein is no longer made.(10)

Punett Square for Cri Du Chat Syndrome
||=   **__a__**    ||=   **__a__**   ||
 * =  **A**   ||=   **A__a__**   ||=   **A__a__**   ||
 * =  **A**   ||=   **A__a__**   ||=   **A__a__**   ||

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Refrences
"What is Cri Du Chat?" __Cri Du Chat Support Group of Australia__. 9 Mar. 2007. 8 Jan. 2009 <http://criduchat.asn.au/criduchat/what.htm#Treatment>. (1)

__Cri Du Chat Syndrome__. 12 Dec. 2008. The University of Utah. 10 Jan. 2009 <http://learn.genetics.utah.edu/content/disorders/whataregd/cdc/>.(7)

__Cri-Du-Chat Syndrome__. 9 Jan. 2004. www.emedicine.com. 10 Jan. 2009 <http://rarediseases.about.com/cs/criduchatsynd/a/010704.htm>.(2)

__Medline Plus Medical Encyclopedia__. 5 Jan. 2009. American Accreditation HealthCare Commission. 10 Jan. 2009 <[|http://www.nlm.nih.gov/medlineplus] ency/article/001593.htm>.(3)

__Youtube-Connor's Cat Cry__. 8 May 2007. 10 Jan. 2009 <http://www.youtube.com/ watch?v=1I0lf408vLo>.(8)

__A Healthy Me!__ 12 May 2006. Accreditation HealthCare Commission. 10 Jan. 2009 <http://www.nlm.nih.gov/MEDLINEPLUS/ency/images/ency/fullsize/17256.jpg>.(6)

Pinna Abnormalities. 14 Jan. 2007 Accreditation HealthCare Commission. 10 Jan. 2009 [|<http://www.nlm.nih.gov/medlineplus/ency/images/ency/fullsize/17281.jpg]>.(4)

__Human Hand__. 9 Nov. 2000. Red Phoenix. 10 Jan. 2009 <[|http://www.humanhand.com/ images/simianlinehand.jpg]>.(5)

<span style="background-color: rgb(53, 255, 0);"> __Cri Du Chat Syndrome__. 7 July 2007. University of Maryland Medical Center. 10 Jan. 2009 <http://www.umm.edu/ency/article/001593prv.htm>.(9)

__Youtube-Cri Du Chat__. 16 Jan. 2008. 11 Jan. 2009 <http://www.youtube.com/ watch?v=pxh9m1dTU0Q&feature=related>. (10)

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