Phenotypic Expression Of Prader Willi Syndrome

Abstract

rader Willi syndrome (PWS) is a neurogenetic disorder associated with abnormalities in the chromosomal region 15qll-13 of paternal origin.

It is characterized by neonatal hypotonia, feeding problems, obesity, characteristic facial features, hypogonadism, mental retardation and behavioral problems.

Deletion of 15qll-13 accounts for 60% of cases. 20-25% of cases have maternal uniparental disomy, the remainder of cases are attributed to either genomic imprinting defect or translocation.

In our study, all patients who presented with obesity and/ or hypogonadism and are registered at the Medical Genetics Center, Ain Shams University, were recalled and subjected to the following: full clinical history, index pedigree analysis, clinical assessment and investigations.

The aim of the study was to determine the phenotypic criteria of PWS. It was found that the most frequent major • diagnostic criteria were: neonatal and infantile central hypotonia with poor suckling, central obesity, global developmental delay and hyperphagia, each of the above criteria affected 100% of patients.