P602: FXN repeat-primed PCR and long-read sequencing reveal non-canonical repeat expansions

Genetics in Medicine Open 2026 Open access

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Authors: Benjamin Obadia, Alison Nguyen, Tony Tran Yonce, Luis Jazo, Jhett Bordwell, Jack Roach, John Alexander
DOI: 10.1016/j.gimo.2026.104093
Cited by: 0

Abstract

Friedreich ataxia (FRDA) is an autosomal recessive neurodegenerative disorder caused by pathogenic variants in the FXN gene, with an estimated incidence of 1 in 15,000 to 1 in 40,000 live births. Our laboratory implemented a repeat-primed PCR (RP-PCR) assay followed by capillary electrophoresis (CE) to detect GAA trinucleotide repeat expansions in FXN. The assay detects full-length PCR products from GAA alleles ≤ 100 repeats, while larger alleles with expanded repeats generate a characteristic stutter pattern indicative of pathogenic expansion.

Fields of Study & Subjects

Genetic Neurodegenerative Diseases Hereditary Neurological Disorders Genomics and Rare Diseases

Publication details

Journal / source
Genetics in Medicine Open
Volume
4
Pages
104093–104093
Publication date
1 January 2026
Language
EN