Case report: A novel variant (H49N) in Myelin Protein Zero gene is responsible for a patient with Charcot–Marie–Tooth disease

This report presents a case of Charcot–Marie–Tooth dominant intermediate D (CMTDID), a rare subtype of Charcot–Marie–Tooth disease, in a 52 years-old male patient. The patient exhibited mobility impairment, foot abnormalities (pes cavus), and calf muscle atrophy. Whole exome sequencing and Sanger sequencing suggested that a novel variant (NM_000530.8, c.145C>A/p.His49Asn) of MPZ may be the genetic lesion in the patient. The bioinformatic program predicted that the new variant (p.His49Asn), located at an evolutionarily conserved site of MPZ , was neutral. Our study expands the variant spectrum of MPZ and the number of identified CMTDID patients, contributing to a better understanding of the relationship between MPZ and CMTDID.