Medical Q&As

Prader-Willi Syndrome - what is it?

What is Prader-Willi Syndrome?

Prader-Willi Syndrome is a rare inherited disorder that occurs as a result of a spontaneous genetic error in chromosome 15. The error occurs around the time of conception but its cause is unknown. Infants with this syndrome have difficulties feeding and exhibit poor weight gain. As the child grows older the appetite increases and they can gain weight rapidly leading to excessive obesity. Mental retardation is a feature of the syndrome with global developmental delay and ongoing learning difficulties. Arrested sexual development is also a feature of the condition. Boys can have a very small penis and may have undescended testicles. The testicles may also be very immature in their development. Girls may have incomplete development of the ovaries with scant or totally absent periods. Onset of puberty can be significantly delayed in both sexes. General health is usually good in individuals with Prader-Willi Syndrome provided their weight is controlled. However, weight control can be difficult because the affected person may actually go foraging for food and continue to eat in a compulsive manner. This can create great stress for the parents because the child’s urge to eat is physiological and can be overwhelming. Infants and young children with Prader-Willi Syndrome are typically happy and loving however as they progress through childhood and into adolescence behavioural difficulties can arise. You might find the following link helpful in learning more about Prader-Willi Syndrome: http://www.pwsausa.org/faq.htm