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Updated: Aug 6, 2026
07:34
FISH for Pre-implantation Genetic Diagnosis
Published on: February 23, 2011
Familial Prader-Willi syndrome with apparently normal chromosomes
M Lubinsky1, H Zellweger, L Greenswag
1University of Nebraska Medical Center, Omaha.
American Journal of Medical Genetics
|September 1, 1987
Summary
This study details four siblings diagnosed with Prader-Willi syndrome (PWS), a rare genetic disorder. Despite normal chromosome studies, the familial occurrence suggests potential genetic factors influencing PWS development.
Area of Science:
- Genetics
- Pediatrics
- Rare Diseases
Background:
- Prader-Willi syndrome (PWS) is a complex genetic disorder affecting multiple body systems.
- Familial occurrence of PWS is uncommon, prompting further investigation into its genetic underpinnings.
- Clinical diagnosis relies on characteristic historical, behavioral, and physical findings.
Purpose of the Study:
- To report an unusual familial occurrence of Prader-Willi syndrome (PWS) in four siblings.
- To discuss the implications of this familial aggregation for understanding PWS etiology.
- To highlight the challenges in diagnosing PWS, especially in infants.
Main Methods:
- Clinical assessment of four siblings, including history, behavior, and physical examination.
- Review of clinical data for a deceased sibling with PWS-typical symptoms.
- Karyotyping of parents and surviving siblings to assess chromosomal abnormalities.
Main Results:
- Four siblings (2 male, 2 female) presented with clinical features consistent with Prader-Willi syndrome.
- One sibling died at 10 months with symptoms typical of early-stage PWS.
- Chromosome studies in parents and surviving siblings revealed normal karyotypes.
Conclusions:
- The familial occurrence of PWS in this cohort, despite normal chromosomal findings, suggests potential non-classical genetic mechanisms.
- Further research is warranted to explore genetic factors contributing to familial PWS.
- This case underscores the importance of thorough clinical evaluation for PWS diagnosis.
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