Prader-Willi syndrome and early-onset morbid obesity NIH rare disease consortium: A review of natural history study.

Merlin G Butler,Roy Tamura,June A Gold,Daniel J Driscoll,Elisabeth Dykens,Virginia Kimonis,Jennifer Miller

doi:10.1002/ajmg.a.38582

Abstract

We describe the National Institutes of Health rare disease consortium for Prader-Willi syndrome (PWS) developed to address concerns regarding medical care, diagnosis, growth and development, awareness, and natural history. PWS results from errors in genomic imprinting leading to loss of paternally expressed genes due to 15q11-q13 deletion, maternal disomy 15 or imprinting defects. The 8 year study was conducted at four national sites on individuals with genetically confirmed PWS and early-onset morbid obesity (EMO) with data accumulated to gain a better understanding of the natural history, cause and treatment of PWS. Enrollment of 355 subjects with PWS and 36 subjects with EMO began in September 2006 with study completion in July 2014. Clinical, genetic, cognitive, behavior, and natural history data were systematically collected along with PWS genetic subtypes, pregnancy and birth history, mortality, obesity, and cognitive status with study details as important endpoints in both subject groups. Of the 355 individuals with PWS, 217 (61%) had the 15q11-q13 deletion, 127 (36%) had maternal disomy 15, and 11 (3%) had imprinting defects. Six deaths were reported in our PWS cohort with 598 cumulative years of study exposure and one death in the EMO group with 42 years of exposure. To our knowledge, this description of a longitudinal study in PWS represents the largest and most comprehensive cohort useful for investigators in planning comparable studies in other rare disorders. Ongoing studies utilizing this database should have a direct impact on care and services, diagnosis, treatment, genotype-phenotype correlations, and clinical outcomes in PWS.

Highlights

Rare diseases affect about 200,000 people or nearly 1 in 1,500 people in the United States but present a significant and growing health care concern nationwide (Rare Disease Act of 2002-PL 107–280)
The methodology used consisted of systematic recruitment and enrollment of individuals with Prader–Willi syndrome (PWS) and those with non-PWS early-onset morbid obesity (EMO); and collection of data utilizing approved data collection forms leading to an 8 year multicenter longitudinal observational natural history study conducted at four different sites by investigators who are experts in the study of PWS
Our historical National Institutes of Health (NIH) rare disease consortium for Prader–Willi syndrome is the largest PWS cohort studied to date

Summary

Introduction

Rare diseases affect about 200,000 people or nearly 1 in 1,500 people in the United States but present a significant and growing health care concern nationwide (Rare Disease Act of 2002-PL 107–280).

Results

Conclusion