Comparative Analysis on Methylation Levels of Nerve and Stress Related Genes in Charcot-Marie-Tooth Disease Type 1A Patients

Abstract

Background: Charcot-Marie-Tooth disease type 1A (CMT1A) is caused by duplication of the 17p12 region including <i>PMP22</i> gene. In CMT1A patients, anticipation showing increased severity by generations has been reported in the CMT1A patients. It has also been reported that severity increases in the non-<i>de novo</i> cases than in the <i>de novo</i> cases. This study was performed to examine epigenetic differences between CMT1A cases and controls as well as between de novo cases and non-<i>de novo</i> cases.Methods: This study examined 40 Korean CMT1A patients and 11 controls. Methylation level was determined using the SureSelect XT Methyl-Seq reagent kit and bisulfite sequence mapping program.Results: Many differentially methylated CpG sites (DMCs) were identified in the comparisonbetween cases and controls and between <i>de novo</i> cases and non-<i>de novo</i> cases. Most DMCs were located within or nearby genes related to the nervous system, mental stress, and motor ability.Conclusions: This study is the first epigenetic study to uncover the mechanism of clinical heterogeneity among CMT1A patients. We suggest that weak severity in the <i>de novo</i> cases than the non-<i>de novo</i> cases may be related to the epigenomic differences in the nerve and stress-related genes.