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Removal of an Internal Translational Start Site from mRNA While Retaining Expression of the Full-Length Protein
Published on: March 16, 2022
Genome-wide androgenetic mosaicism
J P Johnson1, J Waterson, C Schwanke
1Medical Genetics, Shodair Children's Hospital, Helena, MT, USA.
Clinical Genetics
|March 21, 2013
Summary
Mosaic paternal uniparental disomy (UPD) affects multiple chromosomes, causing conditions like Beckwith-Wiedemann syndrome and Angelman syndrome. This case highlights the need for comprehensive genetic testing in complex pediatric cases.
Area of Science:
- Genetics
- Epigenetics
- Pediatrics
Background:
- Mosaic paternal uniparental disomy (UPD) involves a mix of normal cells and cells with two paternal copies of a chromosome.
- Recent studies describe individuals with mosaic paternal UPD affecting multiple chromosomes.
Observation:
- An infant presented with Beckwith-Wiedemann syndrome (BWS) features and severe, refractory hypoglycemia.
- Initial methylation studies for BWS incidentally tested for Angelman syndrome (AS).
Findings:
- The infant exhibited hypomethylation consistent with both BWS and AS.
- Genetic analysis revealed mosaic paternal UPD for chromosomes 11 (BWS) and 15 (AS).
- SNP microarray analysis indicated mosaic paternal UPD across all chromosomes.
Implications:
- Unusual imprinting disorder phenotypes warrant broader genetic investigation beyond typical loci.
- Chromosome SNP microarrays are crucial for detecting multiple UPDs, including whole-genome UPD.
- This case underscores the diagnostic utility of comprehensive genetic testing in infants with complex medical issues.
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