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Prader-Willi syndrome

Other Names for this Disease
  • Obesity, muscular hypotonia, mental retardation, short stature, hypogonadotropic hypogonadism, and small hands and feet
  • Prader Labhart Willi syndrome
  • PWS
  • Willi-Prader syndrome
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Prader-Willi syndrome (PWS) is a complex genetic condition that affects many parts of the body.[1] At birth, babies with PWS have poor muscle tone and a weak cry. Initially, they are slow feeders and appear undernourished. The feeding problems improve after infancy and often between 2 to 4 years of age, children with PWS become very focused on food and have difficulty controlling their appetite. The overeating often results in rapid weight gain and obesity. Individuals with PWS also often have developmental delays and less-than-average adult height. PSW is caused by missing or non-working genes on chromosome 15. Most cases are not inherited, but occur randomly.[2][3]
Last updated: 4/1/2011


  1. Prader-Willi syndrome. Genetics Home Reference (GHR). July 2009; Accessed 3/24/2011.
  2. O'Reilly D. Prader-Willi syndrome. MedlinePlus. November 2, 2009; Accessed 3/24/2011.
  3. Cassidy SB, Schwartz S. Prader-Willi Syndrome. GeneReviews. September 2009; Accessed 3/24/2011.
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Basic Information

In Depth Information

  • The Online Mendelian Inheritance in Man (OMIM) is an catalog of human genes and genetic disorders. Each entry has a summary of related medical articles. It is meant for health care professionals and researchers. OMIM is maintained by Johns Hopkins University School of Medicine. 
  • Orphanet is a European reference portal for information on rare diseases and orphan drugs.  Access to this database is free of charge.
  • PubMed is a searchable database of medical literature and lists journal articles that discuss Prader-Willi syndrome. Click on the link to view a sample search on this topic.