Novel compound heterozygous missense mutations in GDAP1 cause Charcot-Marie-Tooth type 4A.

Homozygous or compound heterozygous mutations in the GDAP1 gene cause Charcot-Marie-Tooth (CMT4A) that are consistent with an autosomal recessive mode of inheritance. The case reported in this study is clinically and genetically diagnosed with recessive CMT4A that is caused by a compound novel heterozygous GDAP1 mutation. The genomic DNA of the proband with the clinical diagnosis of CMT was screened for GDAP1 mutations using a targeted next-generation sequencing (NGS) gene-panel that comprised of 27 CMT genes. Two novel compound heterozygous amino acid changing variants were identified in the GDAP1 gene, c.246C>G p.His82Gln in exon 2 and c.614T>G p.Leu205Trp in exon 5. The two amino acid changing variants were not previously reported in the 1000 Genome, Mutation Taster and gnomAD. Our findings expand the phenotypic characterization of the two novel heterozygous mutations associated with CMT4A (AR-CMT1A) and add to the repertoire of GDAP1 mutations related to autosomal recessive CMT in Chinese populations.