[Clinical practice guidelines for Prader-Willi syndrome].

Prader-Willi syndrome (PWS) is the first multi-systemic genetic disorder known to be caused by imprinting defect. The clinical manifestations of PWS vary with age. At the prenatal stage, decreased fetal movements are frequent. The major clinical manifestations during neonatal period include hypotonia, weak cry, poor suck and feeding difficulties. Growth retardation and delayed language and motor development are observed during infancy. Short stature, small hands and feet, cognitive deficiency are noticed in the childhood. At adolescence, prominent growth retardation, obesity, gonadal dysplasia, abnormal behavior and learning difficulties are the major issues. Morbid obesity caused by insatiable appetite is the major factor for prognosis. Early diagnosis and intervention play a significance role in improving the quality of life, preventing serious complications and prolonging survival. This guideline covers the clinical manifestations, developmental process, pathogenesis, molecular diagnosis and genetic counseling of PWS, with an aim to provide reference for clinicians for early identification, proper intervention and genetic counseling for this disease.