关键词: Charcot-Marie-Tooth病5型；　PRPS1基因；　临床表型

Abstract: Objective　To explore the phenotype and genotype characteristics of X-linked recessive Charcot-Marie-Tooth disease type 5 (CMTX5). Method　The clinical data of CMTX5 in a child were retrospectively analyzed and relevant literature was reviewed. Results　A boy suffered from hearing loss since childhood. At the age of 6, the child presented with walking weakness and abnormal gait with progressive aggravation. Electromyography suggested multiple peripheral neurogenic lesions, mainly involving sensory and motor axons with demyelination. Gene sequencing indicated that there was a hemizygous variation of c.344T> C in the PRPS1 gene, and the same site had a heterozygous mutation in his mother while his father's was normal. The heterotopia has been reported in the past, but difference from the previously reported phenotype is that there is no visual impairment in the child. Eight CMTX5 patients with 8 genotypes were retrieved in the literature and all were missense mutations. All 8 patients had hearing loss and peripheral neuropathy, and 4 had visual impairment. Conclusion　Even patients with the same genotype of CMTX5 have different clinical phenotypes. The phenotypic-genotype correlation requires further studies with large sample size.

Key words: 　X-linked Charcot-Marie-Tooth disease type 5;　PRPS1 gene;　clinical phenotype