Low level of mosaicism in atypical Prader Willi syndrome: detection using fluorescent in situ hybridization
Vandana Chaddha1, Savita Agarwal, S R Phadke
1Department of Medical Genetics, Sanjay Gandhi Post Graduate Institute of Medical Sciences, Lucknow 226 014, India.
Abstract:
Prader Willi syndrome (PWS) most commonly is due to paternal micro-deletion of 15q11-q13. Although PWS is not a rare condition, mosaic micro-deletion cases are reported rarely. FISH using PWS micro-deletion probe is the most useful method to detect deletion including mosaicism. In this report we describe a female child with clinical features of atypical PWS and FISH analysis showing mosaicism for deletion in the PWS critical region. This is first mosaic deletion case of PWS from Indian subcontinent.
Insights
Prader Willi syndrome (PWS) is usually caused by a deletion on chromosome 15. This report details a rare mosaic micro-deletion case of PWS in a female child, the first from the Indian subcontinent.
Area of Science:
- Genetics
- Molecular Biology
- Pediatrics
Background:
- Prader Willi syndrome (PWS) is a complex genetic disorder typically caused by a paternal micro-deletion of the 15q11-q13 region.
- While PWS is relatively common, cases involving mosaic micro-deletions are infrequently reported in scientific literature.
Observation:
- This study focuses on a female child presenting with atypical clinical features suggestive of Prader Willi syndrome.
- Diagnostic investigations included fluorescence in situ hybridization (FISH) analysis, a key method for detecting deletions and mosaicism.
Findings:
- FISH analysis revealed mosaicism for a deletion within the critical PWS region (15q11-q13).
- This represents the first documented case of mosaic micro-deletion in Prader Willi syndrome originating from the Indian subcontinent.
Implications:
- This finding expands the understanding of genetic variations in Prader Willi syndrome, highlighting the importance of detecting mosaicism.
- The case underscores the utility of FISH analysis in diagnosing rare genetic conditions, particularly in atypical presentations.
- This report contributes valuable data on PWS prevalence and genetic characteristics within the Indian population.
