Prader-Willi Syndrome

What is Prader-Willi Syndrome?

Prader-Willi syndrome is a complex genetic condition. Various studies have shown that between 1 in 15,000 to 25,000 children are born with Prader-Willi syndrome and it affects all races and both sexes equally. Prader-Willi syndrome is rare and most people, including many physicians and caregivers as well as new parents and family members, are not familiar with this syndrome.


PWS occurs when there is lack of expression of one or more genes in a specific region on the chromosome 15 that was inherited from the father, the precise location of the abnormality being designated as 15(q11-q13).


People with Prader-Willi syndrome have an abnormality in the part of their brain (the hypothalamus) that helps determine changes in feelings of hunger before and after eating. They have this continuous urge to eat that is very different from the period of poor eating in the early years. PWS is also associated with difficulties in learning, behavioural impairments (such as manipulative and obsessive-compulsive behaviours) and other social impairments (such as difficulties interpreting and using social cues).

Treatment and intervention

There is currently no cure for Prader-Willi syndrome and there is no known treatment to lessen the drive to eat, although much research is being conducted in this area.

However, the lives of people with Prader-Willi syndrome can be significantly improved through having a sound understanding of the syndrome and access to good informed care and support.

‚ÄčTreatment is primarily symptomatic and most importantly consists of:

  • Early diagnosis, provision of information and support with interventions.
  • Lifetime weight control through diet, environmental controls (limited access to food), and exercise.
  • Growth hormone replacement therapy when available.
  • Sex hormone replacement therapy when available
  • Support strategies that seek to minimise behaviour difficulties and which support activities and social engagement that helps maintain wellbeing

With appropriate support and information and the effective management of specific aspects of the syndrome, people with Prader-Willi syndrome can expect to live healthy and increasingly long lives.

Social Cognition and Reward processing in Prader-Willi Syndrome

We are excited to open the door to our new cognition lab to children, teenagers and adults with PWS as we start to recruit participants for our new study looking at social cognition and reward processing in PWS.

Social cognition is our ability to understand the thoughts and feelings of other people. It helps us develop relationships and behave appropriately in social situations. Social cognition is different in people with PWS. Hyperphagia might affect some aspects of social cognition and we want to learn more about this.

We need to develop our understanding of social cognition in people with PWS and see how it may be impacted by hyperphagia and contribute to co-occurring mental health conditions.

What does this study involve?

1. A visit to the Trinity Centre in St James's Hospital:

Participants will visit us in our research lab and we will trace participant's eyes movements using a small camera while they look at pictures and clips on a computer screen (45min). We will record our participants' brain activity through an EEG. This is a safe and non invasive procedure (1 - 2hrs).

‚Äč2. Online Clinical Interviews:

We will do some online interviews with participant's caregivers to understand all about each participant's behaviour and development.

If you are interested in hearing more about PWS research, please email

Prader-Willi Syndrome Research