What is Prader-Willi syndrome?

Prader-Willi syndrome is a genetic disorder that affects development and growth.

Prader-Willi syndrome is caused by missing genes on chromosome 15. This problem with the chromosome happens by chance.

This syndrome is a rare condition, which happens in 1 in 10 000-25 000 births. It affects boys and girls equally.

Signs and symptoms of Prader-Willi syndrome

Physical characteristics
Children with Prader-Willi syndrome are typically floppy when they’re newborns. They have feeding difficulties because their weak muscles make it hard for them to suck.

Low muscle tone also means that it takes children with Prader-Willi syndrome longer to reach developmental milestones like sitting, crawling and walking.

Other physical signs and symptoms can include:

  • facial features like a narrow bridge of the nose, a high and narrow forehead, a thin upper lip and downturned mouth, almond-shaped eyes, and eyes that look in different directions (strabismus)
  • failure to thrive in infancy
  • obesity from overeating, which can start between six months and six years
  • undescended testes and small genitalia in boys
  • irregular or no periods in girls
  • higher tolerance of pain
  • small hands and feet
  • light skin and hair compared with other people in the family
  • short stature
  • extreme muscle flexibility
  • curved spine (scoliosis).

Cognitive signs
Children with Prader-Willi syndrome usually have mild to moderate intellectual disability. They might have:

  • difficulty with maths, writing and memory
  • poor social and emotional skills
  • speech delay.

Behavioural signs
One of the key characteristics of Prader-Willi syndrome is excessive appetite and obesity. This includes:

  • overeating
  • too much weight gain
  • strong preoccupation with food.

Some children with Prader-Willi syndrome might also have sleep problems and compulsive behaviour, including picking at their skin and collecting objects.

Medical concerns linked with Prader-Willi syndrome
Children with Prader-Willi syndrome can have other medical concerns like:

They might also have symptoms of many illnesses but not realise it, because they can put up with a lot of pain.

Children with Prader-Willi syndrome have strengths in reading, art and vocabulary.

Diagnosis and testing for Prader-Willi syndrome

Health professionals diagnose Prader-Willi syndrome by looking at the physical and other signs listed above, and by using genetic testing.

Early intervention services for children with Prader-Willi syndrome

Although there’s no cure for Prader-Willi syndrome, early intervention can make a difference. Through early intervention services, you can work with health professionals to treat your child’s symptoms, support your child, improve outcomes for your child and help him reach his full potential.

The team of professionals involved in supporting you and your child might include paediatricians, dietitians, physiotherapists, speech pathologists, endocrinologists, occupational therapists and special education teachers.

Together, you and your team can choose treatment and therapy options to best help your child.

Services and support for children with Prader-Willi syndrome

Getting information
Learning as much as possible from your specialists will help. It’s OK to ask lots of questions.

Many services and supports can help your child with Prader-Willi syndrome achieve her potential. But finding your way through the disability services system can be tricky.

Financial support
If you live in a National Disability Insurance Scheme (NDIS) trial area and your child has a confirmed diagnosis of Prader-Willi syndrome, your child can get support under the NDIS. The NDIS helps you get services and support in your community, and gives you funding for things like early intervention therapies or educational support.

If you don’t live in one of the NDIS trial areas, your child can get funding under the Better Start for Children with Disability initiative. If your child is eligible for the NDIS, he’ll be moved over when it becomes available in your area. Read our NDIS and Better Start FAQs for more information.

Looking after yourself and your family

If your child has Prader-Willi syndrome, it’s easy to get caught up in looking after her. But it’s important to look after your own wellbeing too. If you’re physically and mentally well, you’ll be better able to care for your child.

If you need support, a good place to start is with your GP and genetic counsellor. You can also get support from organisations like Genetic Alliance Australia.

Looking after siblings
Siblings of children with disability have good times and not so good times, just like everyone else. It’s important to find the right support for them too.

Talking to other parents can be a great way to get support. You can connect with other parents in a similar situation by joining a support group.