Diagnostic and prognostic problems with the Prader-Willi syndrome.

Prader-Willi syndrome (PWS) is a rare neurodevelopmental disorder resulting from chromosomal duplications, deletions, or imprinting within the 15q11-q13 region. In most cases, patients with PWS inherit a de novo paternally inherited deletion, and the remaining result from maternal disomy 15 and imprinting. Currently, DNA methylation analysis remains the gold standard for diagnosing PWS. However, this diagnostic test provides no information concerning the molecular class of PWS. As a result, clinicians remain unable to accurately determine diagnostic and prognostic information for patients with PWS. Further research is needed toward establishing standardized, accurate, and cost-effective testing methods for diagnosis and treatment of patients with PWS.