Definitions for prader-willi syndrome
This page provides all possible meanings and translations of the word prader-willi syndrome
A particular human disease, caused by deletion of part of chromosome 15, and manifested by mental retardation and other problems.
U.S. National Library of Medicine
An autosomal dominant disorder caused by deletion of the proximal long arm of the paternal chromosome 15 (15q11-q13) or by inheritance of both of the pair of chromosomes 15 from the mother (UNIPARENTAL DISOMY) which are imprinted (GENETIC IMPRINTING) and hence silenced. Clinical manifestations include MENTAL RETARDATION; MUSCULAR HYPOTONIA; HYPERPHAGIA; OBESITY; short stature; HYPOGONADISM; STRABISMUS; and HYPERSOMNOLENCE. (Menkes, Textbook of Child Neurology, 5th ed, p229)
Prader–Willi syndrome is a rare, genetic disorder in which seven genes on chromosome 15 are deleted or unexpressed on the paternal chromosome. It was first described in 1956 by Andrea Prader, Heinrich Willi, Alexis Labhart, Andrew Ziegler, and Guido Fanconi of Switzerland. Characteristic of PWS is "low muscle tone, short stature, incomplete sexual development, cognitive disabilities, problem behaviors, and a chronic feeling of hunger that can lead to excessive eating and life-threatening obesity." The incidence of PWS is between 1 in 25,000 and 1 in 10,000 live births. The maternal origin of the genetic material that is affected in the syndrome is important because the particular region of chromosome 15 involved is subject to parent of origin imprinting, meaning that for a number of genes in this region only one copy of the gene is expressed while the other is silenced through imprinting. For the genes affected in PWS, it is the maternal copy that is usually imprinted, while the mutated paternal copy is not functional. This means that while most people have a single working copy of these genes, people with PWS have a non-working copy and a silenced copy. If the maternally derived genetic material from the same region is affected instead, the sister syndrome Angelman syndrome is the result.
Find a translation for the prader-willi syndrome definition in other languages:
Select another language:
Use the citation below to add this definition to your bibliography:
"prader-willi syndrome." Definitions.net. STANDS4 LLC, 2013. Web. 20 Dec. 2013. <http://www.definitions.net/definition/prader-willi syndrome>.