PABPN1 Repeat Analysis
Use
This test detects expansions in the poly(A) binding protein nuclear 1 (PABPN1) gene that cause oculopharyngeal muscular dystrophy (OPMD), by analyzing trinucleotide repeat expansions in exon 1 and identifying the pathogenic p.G12A single-nucleotide variant when present; it provides high sensitivity (~99% of OPMD cases detectable by this method) and technical sensitivity >95% through confirmatory Sanger sequencing.
Special Instructions
Orderable using genomic DNA obtained from blood (2–10 mL in EDTA). Analysis uses bidirectional Sanger sequencing covering the alanine repeat region; repeat number determined by visual inspection and confirmed by repeat Sanger sequencing.
Limitations
This test detects expansions and the p.G12A variant; it may not detect other pathogenic variants outside exon 1 or non‑alanine repeat mutations. Repeat sizing relies on visual inspection which may have limitations in extremely large expansions. The technical sensitivity is estimated >95%, so rare false negatives may occur due to sequencing limitations.
Methodology
Sanger
Biomarkers
Result Turnaround Time
Not provided.
Related Documents
For more information, please review the documents below
Specimen
Whole Blood
Volume
2–10 mL
Minimum Volume
Not provided
Container
EDTA (lavender top) tube
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