Prader-Willi syndrome: What is the condition and what are the symptoms?

Katie Price's son Harvey suffers from the rare genetic condition

(katieprice/instagram)

Prader-Willi syndrome is a rare genetic condition that affects one in 15,000 children in England and causes a wide range of physical symptoms and behavioural problems.

Although the syndrome itself isn't life-threatening, its consequences - such as excessive eating - can cause complications like obesity and diabetes, which can shorten life expectancy.

Usually diagnosed shortly after birth, children with PWS also have learning difficulties.

Katie Price's son, Harvey, was born with the condition and is now starting at a residential college, with access to full-time care, with Price admitting the “heartbreaking" decision was best for her 18-year-old son.

What is Prader-Willi syndrome?

According to the NHS, Prader-Willi syndrome is a genetic condition that can impact muscle tone, sexual development and the function of the nervous system.

Those with Prader-Willi syndrome are more likely to have learning difficulties and the condition often leaves sufferers with permanent feelings of hunger, no matter how much they eat.

The syndrome is very rare, with the NHS estimating that it affects "no more than one in every 15,000 children born in England".

What are the symptoms?

Typical symptoms of Prader-Willi syndrome include:

• An excessive appetite and overeating - a child with the syndrome can eat three to six times more than other children of the same age and still feel hungry
• Restricted growth 
• Floppiness caused by weak muscles (hypotonia)
• Learning difficulties
• Lack of sexual development
• Behavioural problems, such as temper tantrums and stubbournnes

There is no known cure for the syndrome and treatment aims to manage the symptoms and associated problems. 

What causes Prader-Willi syndrome and how is it diagnosed?

Those with PWS have a genetic defect on chromosome number 15.

In around 70 per cent of cases, some of the DNA information that's inherited from the father is missing, which is referred to as "paternal deletion".

Other cases occur when a child has two copies from their mother and none from their father.

The condition is obtained purely by chance, but those who have one child with PWS have a less than one per cent chance of the next one being affected.

PWS can usually be diagnosed with a genetics test carried out by a medical professional.

Children may be recommended for genetic testing if they have the symptoms of PWS, says the NHS. Testing may be done in babies who are very floppy when they are born.

The Prader-Willi Syndrome Association UK (PWSA UK) provides information and support for people whose lives are affected by the condition. You can call the PWSA helpline on 01332 365676.