Identification of a rare missense mutation in GJB1 and prenatal diagnosis in a Chinese family with CMT: A case report

Charcot-Marie-Tooth disease (CMT) is a highly heterogeneous genetic disorder. To date, more than 90 genes have been implicated in the pathogenesis of CMT. Here, we report the identification of a rare causative mutation in a Chinese family with CMT and a pregnant patient underwent prenatal diagnosis.A 33-year-old woman with 21 + 6 weeks of pregnancy presented with progressive weakness of distal extremities after 23 years of age. A total of 8 individuals in 4 generations of her family had similar muscle weakness. On proband whole-exome sequencing (WES), a rare c.121G > A variant in the GJB1 gene was identified.Based on the clinical and genetic findings, this patient was finally diagnosed with CMT.The prenatal diagnosis was performed on the proband fetus.The fetus did not carry this rare variant, and the pregnancy continued.Our findings provide the first clinical evidence for the causative role of GJB1 c.121G > A variant in CMT. WES is a valuable method for diagnosing patients with CMT.