PraderWillisyndroom

Prader-Willi syndrome (PWS), sometimes referred to as Prader-Willi-syndroom in Dutch, is a genetic disorder caused by loss of paternal gene expression in the 15q11-q13 region of chromosome 15. It arises from disturbances in genetic imprinting that affect this region.

Infancy features include hypotonia and feeding difficulties, followed by hyperphagia and obesity in childhood. Other common findings are short stature, hypogonadism, developmental delays, distinctive facial features, sleep disturbances, and behavioral problems.

Most cases result from a paternal deletion of 15q11-q13 (~70%), about 25% from maternal uniparental disomy, and a minority from imprinting defects. The disorder reflects loss of paternal gene expression in the region.

Diagnosis is based on genetic testing. Methylation analysis confirms most cases; additional testing distinguishes deletion, uniparental disomy, or imprinting-center defects.

Management is multidisciplinary. Growth hormone therapy improves height and body composition. Diet control, activity programs, and behavioral support help manage hyperphagia and weight. Regular endocrine assessment, sleep studies, and monitoring for scoliosis and other medical issues are recommended.

Incidence is about 1 in 10,000 to 30,000 live births. With comprehensive care, individuals can achieve better growth, development, and quality of life, though obesity-related health risks require lifelong management.