Description and Cause
Prader-Willi Syndrome is a neurobehavioral genetic disorder resulting from one of three genetic causes: (1) a paternal deletion on the long arm of chromosome 15 in 70% of cases; (2) uniparental disomy (both chromosomes 15 of maternal origin) 15 in 25% of cases; or (3) an imprinting defect in 5% of cases. (Note: Angelman Syndrome is often discussed with Prader-Willi Syndrome because they share a similar genetic basis; return to the index to view a document on Angelman Syndrome.)
Diagnosis is by chromosomal fine structural analysis, fluorescent antibody in situ hybridization (FISH), or DNA probe. DNA probe analysis, where available, is the technique of choice and is required in order to recognize uniparental disomy.
Note: Many of these associations are secondary results of obesity and therefore may be preventable.
MEDICAL MANAGEMENT CONSIDERATIONS
Note: These considerations are in addition to the normal medical care provided to an individual without Prader-Willi Syndrome. All recommendations can be addressed through clinical examination by the primary care provider, unless otherwise noted.
General physical health usually remains good in persons with Prader-Willi Syndrome unless obesity becomes severe. Typically, the focus of medical management is on maintaining a strict diet of regular, balanced meals. Food restriction can be very challenging and may impact the entire family system. Siblings, extended family members, neighbors, friends, educators and all other caregivers must receive appropriate education and counseling regarding food restriction and the child’s diet. The need to restrict and/or lock food may complicate family interactions and activities, and may cause stress for everyone involved. Siblings may require special support and counseling to help them understand and adjust to these issues.
Ongoing (all ages)
Infancy (Birth to 1 year)
Early Childhood (1 to 5 years)
Late Childhood (5 to 13 years)
Adolescence and Adulthood (13 years and over)
Peer-reviewed Journal Articles/Academies
Cassidy, SB. 1997. “Prader-Willi Syndrome.” Journal of Medical Genetics 34 (11): 917-923.
Hanchett, Jeanne MD and Louise Greenswag RN, PhD. 1998. Health Care Guidelines For Individuals With Prader-Willi Syndrome. The Scientific Advisory Board of the Prader-Willi Syndrome Association (USA). Accessed December 2, 1998 at http://www.pwsausa.org/postion/HCGuide/HCG.htm
Hoffman, Carolyn J, et al. 1992. “A Nutrition Survey of and Recommendations for Individuals with Prader-Willi Syndrome Who Live in Group Homes.” Journal of the American Dietetic Association 92 (7): 823-830.
Marin, Andres, et al. 1998. “Prader-Willi Syndrome.” American Journal of Psychiatry 155 (9): 1265-1273.
Tu, Jun-Bi, et al. 1992. “Psychopharmacogenetic Aspects of Prader-Willi Syndrome.” Journal of the American Academy of Child and Adolescent Psychiatry 31 (6) (November): 1137-1140.
Wodarski, Lois Ann, et al. 1988. “Interdisciplinary Case Management: A Model for Intervention for a Patient with Prader-Willi Syndrome.” Journal of the American Dietetic Association 88 (3): 332-335.
Special Interest Groups/Other Publications
Batshaw, Mark L. and Yvonne M. Perret. 1992. Children with Disabilities. Baltimore: Paul H. Brookes Publishing Co., Inc.
Capute, Arnold J. and Pasquale J. Accardo. 1996. Developmental Disabilities in Infancy and Childhood vol. I: Neurodevelopmental Diagnosis and Treatment. Baltimore: Paul H. Brookes Publishing Co., Inc.
Capute, Arnold J. and Pasquale J. Accardo. 1996. Developmental Disabilities in Infancy and Childhood vol II: The Spectrum of Developmental Disabilities. Baltimore: Paul H. Brookes Publishing Co., Inc.
Dambro, Mark R. 1999. Griffith’s 5 Minute Clinical Consult. Baltimore: Lippincott Williams & Wilkins, p. 1218.
Greenswag, LR and RC Alexander. 1995. Management of Prader-Willi Syndrome (2nd ed). New York: Springer-Verlag.
Hagerman, RJ. 1999. “Angelman syndrome and Prader-Willi syndrome.” In: Neurodevelopmental Disorders: Diagnosis and Treatment. New York: Oxford University Press, pp. 243-290.
Rubin, I. Leslie and Allen C. Crocker. 1989. Developmental Disabilities: Delivery of Medical Care for Children and Adults. Philadelphia: Lea & Febiger.
RESOURCES FOR FAMILIES
California Department of Developmental Services, 916-654-1690, http://www.dds.ca.gov
California Regional Centers, 916-654-1958, http://www.dds.ca.gov/rc/rclist.cfm
Exceptional Parent Magazine, 800-247-8080, http://www.eparent.com/
March of Dimes Birth Defects Foundation, 914-428-7100, http://www.modimes.org
Prader-Willi California Foundation, 800-400-9994, http://www.pwcf.org
The Prader-Willi Connection, 800-358-0682
The Prader-Willi Foundation, Inc., 516-621-2445
Prader-Willi Syndrome Association (USA), 800-926-4797, http://www.pwsausa.org
Theodore A. Kastner, M.D., M.S.
Felice Weber Parisi, M.D., M.P.H.
Robin L. Hansen, M.D.
Joan M. Reese, M.D., M.P.H.
Funded by a grant from the California Department of Developmental Services
For more information, contact:
Center for Health Improvement
1330 21st Street, Suite 100
Sacramento, CA 95814
This document does not provide advice regarding medical diagnosis or treatment for any individual case, and any opinions or statements contained in this document are not intended to serve as a standard of medical care. Physicians are encouraged to view the considerations presented in this document in light of evolving scientific information. This document is not intended for use by the layperson. Reproduction of this document may be done with proper credit given to California Department of Developmental Services and the Center for Health Improvement.