Analysis of Association of Deletion in the Repeat Region of the Periaxin Gene With Late Onset Motor Neuropathy

Abstract

Background: Charcot-Marie-Tooth Disease (CMT) represents a heterogeneous group of disorders affecting the peripheral nervous system. The protein encoded by the periaxin (PRX) gene has a functional role in the maintenance of peripheral nerve myelin. Mutations in the PRX gene have been identified in autosomal recessive forms of Dejerine-Sottas neuropathy and Charcot Marie Tooth disease type 4F. Both of these conditions are characterized by early onset of a demyelinating neuropathy.

Methods: We report two unrelated patients, a Caucasian American and an Asian American patient with late onset progressive neuropathy. We also ascertained family members of the Asian American patient for clinical and genetic evaluation.

Results: We report heterozygous deletions in the repeat region of the PRX gene; the Caucasian patient developed symptoms as a teenager and has a 78 base pair deletion. The Asian patient became symptomatic in his forties and has a 15 base pair deletion and the same deletion was also identified in two other siblings with neuropathy. Both deletion mutations involve the repeat region in exon 7 of the PRX gene. In both patients, electrophysiological analysis demonstrates a predominantly motor neuropathy with demyelinating features.

Conclusions: This is the first report of deletions involving the repeat region in exon 7 of the PRX gene. We present epidemiological data and discuss the possible significance of the association of these deletion mutations with neuropathy.




J Neurol Res. 2012;2(6):235-243
doi: https://doi.org/10.4021/jnr154w