Prader-Willi Syndrome

Prader-Willi Syndrome (PWS, OMIM# 176270) is another rare neurogenetic disorder, often caused by the absence of the paternal imprinted part of chromosome 7 through deletion, uniparental disomy (both copies inherited from the mother), or imprinting defects. It manifests with early-onset hyperphagia leading to obesity if caloric intake is not controlled. Individuals typically experience hypotonia in infancy, delayed motor milestones, cognitive impairment, behavioural problems, and short stature. More info
SHOW MOUSE MODELS

PWS is also associated with characteristic facial features, such as narrow bifrontal diameter, almond-shaped eyes, and a thin upper lip. Early intervention with nutritional and dietary counselling is essential to prevent obesity and manage hyperphagia. Growth hormone therapy can improve height and body composition, while behavioural interventions and structured routines are crucial to manage compulsive eating behaviours and temper tantrums. If caloric intake is controlled, individuals with PWS can lead relatively healthy lives, although lifespan may be reduced due to obesity-related complications if obesity is not adequately managed.

Pathogenic mechanisms

Prader-Willi Syndrome (PWS) results from the absence of paternal genetic material on chromosome 7. This absence leads to the loss of expression of critical imprinted genes (Frat3, Mkrn3, Magel2, Ndn, Snurf, Snrp, Snord107, Snord64, Snord116, Snord115) involved in appetite regulation and growth.

Mouse Models

  • Del(7Herc2-Mkrn3)13FRdni (deletion of the whole PWS region corresponding to PWS deletion Type 1, imported from JAX)