A novel mutation in GNE gene: clinical characteristics and bioinformatics analysis

Abstract

Objective To report and summarize clinical phenotype and genotype characteristics in a patient with GNE myopathy, and to extend mutation spectrum of GNE gene. Methods and Results A male patient, 33 years, characterized by symmetric weakness of bilateral distal lower limbs, especially in anterior group of calf muscles, which was progressive slowly. His parents were consanguineous. The level of serum creatine kinase (CK) was elevated (1139 U/L); electromyography (EMG) presented with myogenic injury; CT results of bilateral lower limbs showed mild muscle atrophy; muscle histology showed dramatically varied sizes of myofibers, centralization of myonuclei, rimmed vacuoles in about 2% of myofibers; genetic testing exhibited homozygous mutation [GNE gene, exon 9, c.1624C > T (p.Pro542Ser)] in the proband and heterozygous mutation [GNE gene, exon 9, c.1624C > T (p.Pro542Ser)] in the proband's mother, son and daughter. This mutation had not been reported and was malignant according to bioinformatics analysis. Furthermore, the mutation was likely pathogenic ( Ⅱ) on the basis of American College of Medical Genetics and Genomics (ACMG) guideline. Thus, the patient was diagnosed as GNE myopathy, and the family was a pedigree with GNE myopathy. Conclusions This study systematically reports genotype and phenotype information of a patient with GNE myopathy, which extends mutation spectrum of GNE gene and improves the understandings of clinic practitioner for GNE myopathy.

DOI: 10.3969/j.issn.1672-6731.2018.08.007