Key Facts
Prader-Willi syndrome is a rare genetic disorder and at present the birth incidence has been estimated at 1 in 20,00 to 1 in 25,000 live births
Prader-Willi syndrome is caused by missing pieces of genetic information on the paternal copy of chromosome 15 (we inherit two copies of each chromosome - one from each parent).
Impaired satiety is common in individuals with Prader-Willi syndrome which leads to excessive eating (hyperphagia) and never feeling full. This accompanied by poor muscle tone leads to an increased risk of obesity and so it is important to monitor eating behaviour and encourage regular activity.
Many children with Prader-Willi syndrome have multiple learning difficulties that can impact their academic performance, but some children may be able to attend mainstream education, with the right level of support.
It is common for individuals with Prader-Willi syndrome to repetitively ask questions and insist on sameness in routines and behaviours.
For children with Prader-Willi syndrome, puberty usually has a later onset.
Sleep problems can be common for individuals with Prader-Willi syndrome. However, there are current research studies aiming to understand why sleep problems occur in people with Prader-Willi syndrome and inform treatment.