Exome sequencing is an efficient tool for genetic screening of Charcot-Marie-Tooth disease

Charcot-Marie-Tooth disease (CMT) is one of the most common inherited neuropathies and is a genetically and clinically heterogeneous disorder with variable inheritance modes. As several molecules have been reported to have therapeutic effects on CMT, depending on the underlying genetic causes, exact genetic diagnostics have become very important for executing personalized therapy. Whole-exome sequencing has recently been introduced as an available method to identify rare or novel genetic defects from genetic disorders. Particularly, CMT is a model disease to apply exome sequencing because more than 50 genes (loci) are involved in its development with weak genotype-phenotype correlation. This study performed the exome sequencing in 25 unrelated CMT patients who revealed neither 17p12 duplication/deletion nor several major CMT genes. This study identified eight causative heterozygous mutations (32%). This detection rate seems rather high because each sample was tested before the study for major genetic causes. Therefore, this study suggests that the exome sequencing can be a highly exact, rapid, and economical molecular diagnostic tool for CMT patients who are tested for major genetic causes.