Prader-Willi syndrome

Methylation studies can also be performed for this disorder.

A syndrome characterized by severe hypotonia, poor feeding in early infancy followed later in infancy by excessive eating that, can lead to obesity if left unchecked. Children with PWS show developmental delay, mild-to-moderate mental retardation with multiple learning disabilities. Hypogonadism is present in females. Short stature and small hands and feet are also common.

Prader-Willi syndrome is due to a chromosome deletion involving loss of material from chromosome region 15q11-q13. The loss is consistently from the father's contribution of chromosome region 15q11-q13. A child with P'wS can have two copies of chromosome region 15q11-13 but both will be from the mother. The opposite condition occurs in patients with Angelman syndrome, with the deletion occurring on the maternal region.

There is currently no specific treatment or cure for PWS. Parents are advised to limit consumption of high-calorie foods, and to use techniques such as special education, speech therapy, and physical therapy to maximize the child's potential.

Methodology: Fluorescent in Situ Hybridization (FISH) Analysis

Purpose: Confirmation of Clinical Diagnosis/Methylation Studies Negative

ICD-9 Code 759.81

Test Requisition: Cytogenetics Requisition

CPT Codes: 88230, 88271, 88274, 88291 Cost: $655.00

Turn-around-time: 7-10 days