Prader-Willi+Syndrome

=Prader-Willi Syndrome= By Jordan and Maria

What is Prader-Willi Syndrome?
Prader-Willi Syndrome or PWR is a genetic disorder of chromosome 15. It is a congenital (present from birth) disease, characterized by decreased muscle tone, failure to grow and gain weight, and impaired mental capacity, and obesity. It causes the sex glands to produce little or no hormones.

Symptoms and Features
There are many symptoms resulting from Prader-Willi Syndrome. Some include slow mental development, delayed motor development, characteristically small hands and feet as compared to the body, rapid weight gain caused by an insatiable appetite, food cravings, almond shaped eyes, and skeletal abnormalities, such as a narrow bifrontal skull. Symptoms also include floppy infants, undescended testicles (male), morbid obesity, and sometimes stretch marks on the skin.

Causes
Prader-Willi Syndrome is caused by a gene or genes being deleted on chromosome 15. The majority of patients have a deletion of the father's DNA, most remaining patients have two copies of the mother's chromosome 15. The mother's copy of this gene is inactive, so with no male copy, chromosome 15 doesn't work. Another cause is translocation, in which some of the chromosome is attached to another. In less than 5 percent of the cases, there is an error in the imprinting of chromosome 15, which means that the copy inherited from the mother acts differently than the one from the father. This is a picture of a normal paternal and maternal chromosome, and the father's affected chromosome, shown in the top left hand corner in light blue.

Who it Affects
Prader-Willi Syndrome affects 1:12,000-15,000 people of both sexes, and all races.

Treatment
While there is no known cure for PWS, the symptoms can be managed. During infancy there are special feeding techniques that can be followed. The physical problems can be managed by doing things such as limiting calorie intake, which will require cooperation on the patient's part, because they will attempt to obtain food whenever posible. Exercise helps to increase lean body mass and taking growth hormones help to improve muscle mass and growth. Speech therapists can help the patient's language skills to develop to an age appropriate level and other treatments such as weight monitoring, a low calorie, balanced diet, food restricton and daily exercise help the patient to try and mask the smptoms of the disorder.

History
The first time Prader-Willi Syndrome appeared in medical literature was in 1956 when endocrinologists Willi, Prader, and Labhart published an article talking about an abnormal pattern of symptoms. Later studies into these cases, in the late 1960's, added more information to these cases. Problems associated with these symptoms were described in 1970's-80's literature. Two easily identifiable phases were determined. Phase 1 was during the prebirth to early infancy stages during which the disordered child showed poor muscle tone, decreased fetal activity, and an incapacity to thrive after birth. Phase 2 is between the ages of 2 and 3, and causes incontrollable hunger. Prader-Willi syndrome is just beginning to receive worldwide recognition. In 1992, the international PWS organization was founded in Holland. Various genetic tests have been developed in recent years to help determine and assist in early diagnosis.

How it can Affect People's Lives
Prader-Willi Syndrome changes people's lives dramatically. Because patients never feel full, they are often obese. People with Prader-Willi Syndrome rarely have an IQ over 80, although they are generally very cheerful and smile frequently. The obese state of many of these people can lead to respiratory failure with low blood oxygen levels, failure in the right side of the heart, and sometimes death. Also, their sex glands may not produce any hormones which may cause infertility (the inability to become fertile). Prader-Willi Syndrome also causes behavioral problems, temper tantrums(especially when food is wanted but can't be obtained), and Obsessive-Compulsive behavior.

This is a picture of a child with Prader-Willi Syndrome, first with a small, undersized figure, then as an obese teenager later in life.

Discussion Questions
1.What, if any, is the cure for PWS? Explain. 2.What are the different causes?(name all) 3.How does it affect people's lives?

Resources
http://rarediseases.about.com/od/rarediseasesp/a/praderwilli.htm

http://www.nlm.nih.gov/medlineplus/ency/article/001605.htm

http://www.bbc.co.uk/health/conditions/praderwilli1.shtml

http://www.pwsausa.org/syndrome/history.htm

http://www.geocities.com/cpwso/history.html

http://www.webmd.com/heart-disease/Prader-Willi-Syndrome