Absence of KIF1B mutation in a large Turkish CMT2A family suggests involvement of a second gene

Abstract

Background: Charcot-Marie-Tooth disease type 2A (CMT2A) was assigned to a 19.3-cM region on chromosome 1p35-36. A missense mutation in the kinesin family member 1B gene (KIF1B) was reported in a single CMT2A family. Objective: To report the clinical and genetic data of a Turkish family with CMT2A. Methods: Linkage to CMT2 loci was investigated in the family. Haplotype analysis of the CMT2A region was completed using additional single-nucleotide polymorphism and short tandem repeat markers. The KIF1B gene was sequenced on genomic DNA and cDNA in two patients. Results: A recombination event narrowed the CMT2A locus to a 9.3-cM region flanked by D1S160 and D1S434. No mutation in KIF1B was found. Conclusion: The exclusion of KIF1B gene mutations in this family suggests the involvement of another CMT2A gene in the linked region.