Prader-Willi Syndrome

Prader-Willi Syndrome, otherwise known as PWS or Prader-Labhart-Willi Syndrome is an

extremely rare, complex genetic condition that affects many parts of the body. For infants, this

condition is characterized by weak muscle tone (hypotonia), feeding difficulties, delayed

development and poor growth. The most noticeable effects take place in the childhoods of those

with PWS, where affected individuals begin to experience extreme hunger, which can lead to

hyperphagia (overeating) and obesity. In many cases, it can also lead to type 2 diabetes.

Individuals with PWS are also known to experience mild to moderate intellectual impairments as

well as other learning disabilities. Furthermore, behavioral problems including temper outbursts,

stubbornness, and compulsive behaviors (picking at the skin) are consistent with individuals that

have PWS. In terms of one’s physical appearance, individuals with PWS may have narrow

foreheads, almond-shaped eyes, triangular mouths, short statures, and/or small hands/feet.

Puberty tends to remain incomplete and most affected individuals turn out to be infertile due to

their underdeveloped genitalia.

Prader-Willi Syndrome is caused by a loss of function of genes in the general area of

chromosome 15. People usually inherit this chromosome from both parents, but some genes

may only be active from the paternal side. This parent-specific gene copying results from

genomic imprinting. About 70% cases of PWS occur when the paternal segment of

chromosome 15 is deleted from each cell, which results in several genes being missing, as the

paternal copy of the chromosome has been deleted, and the maternal copy is entirely inactive.

In another 25% of PWS cases, the affected individual has inherited two copies of chromosome

15 from their mother, as opposed to one copy from each parent, known as uniparental disomy.

The most rare causes for the development of PWS include translocation, a chromosomal

rearrangement, or a genetic alteration or other change that abnormally inactivated the paternal

copy of chromosome 15.

Diagnosis for Prader-Willi Syndrome is completed through a blood test. Although there is

no cure present for the condition, there are treatments available for usage. Such treatments

include good nutrition for infants, human growth hormone treatment, sex hormone treatment,

weight management, behavior management, various therapies, treatments for sleep disturbance, mental health care, as well as many more. Treatments for PWS largely depend on the individuals affected by the condition. While living as an individual with PWS can be very difficult, it can also be tolling on people that live with and take care of others with PWS, and it is important to take care of the mental health of everyone involved in such scenarios.