Last update: 05/06/2006

Background to disease

OMIM #164300 (PAPB2 Gene OMIM *602279)

Oculopharyngeal muscular dystrophy (OPMD) is an autosomal dominant adult onset disorder characterised by progressive drooping of the eyelids, difficulty swallowing and limb muscle weakness. The main morpoligic feature of OPMD is the collection of 8.5 nm tubular filaments inside muscle fibre nuclei.

OPMD is caused by a small expansion of a GCG repeat in polyA-binding protein 2 (PAPB2). Normal alleles have 6 repeats while the affected range is from 8 – 13 GCG repeats. The (GCG)₇ allele is thought to be a polymorphism that can also act as a phenotype modifier and might affect disease severity.

Laboratory Analysis

Contact scientist: Rachel Robinson

	Test	Target reporting time (working days)
1.	GCG repeat sizing	40

^aAnalysis will detect ~55% of mutations reported in patients of European origin (Toomes et al. Hum Mol Genet 10:1369-1379) and 30% of mutations reported on the online database for OPA1 mutations (www.lbbma.univ-angers.fr/eOPA1).