Prader-Willi syndrome is a very variable genetic disorder and is the most common life-threatening genetic cause of obesity known in children. It is caused by the absence of expression of genes found on the paternal-origin chromosome 15 (region 15q11.2–q13).
The prevalence is estimated at 1 in 10,000-30,000 births. Life expectancy is normal (but only if weight is controlled).
Most frequent clinical findings in patients with Prader-Willi syndrome (region 15q11.2–q13):
- Low muscular tone (hypotonia)
- Growth deficiency and developmental delay
- Wide forehead
- Chronic overeating
- Light intellectual deficit
- Underdeveloped genitals
- Low levels of sexual hormones
- Delayed or incomplete puberty
Pwsausa.org – Prader-Willi Syndrome Association
Ipwso.org – International Prader-Willi Syndrome Organization