Clinical and genetic analysis of CMT1B in a Nigerian family.

We report a Nigerian family with a late-onset autosomal dominant neuropathy consistent with Charcot-Marie-Tooth disease. Electrophysiological examination of the index patient confirmed a severe demyelinating neuropathy with secondary axonal features. Sequence analysis of the myelin protein zero (MPZ) gene identified a C-to-G transversion at nucleotide position 234, resulting in a serine-to-tryptophan mutation in codon 78 (S78W) of the translated protein. The presence of this novel missense mutation suggests a diagnosis of Charcot-Marie-Tooth disease type 1B. Our study confirms the worldwide distribution of this disorder and extends the genetic spectrum of mutations in the MPZ gene.