Ann Rehabil Med.  2015 Jun;39(3):494-497. 10.5535/arm.2015.39.3.494.

Novel Mutation of the GNE Gene Presenting Atypical Mild Clinical Feature: A Korean Case Report

• Choi YA
• Park SH
• Yi Y
• Kim K

• KMID: 2165655
• DOI: http://doi.org/10.5535/arm.2015.39.3.494

Abstract

Glucosamine (UDP-N-acetyl)-2-epimerase/N-acetylmannosamine kinase (GNE) myopathy is caused by mutations in GNE, a key enzyme in sialic acid biosynthesis. Here, we reported a case of GNE that presented with atypical mild clinical feature and slow progression. A 48-year-old female had a complaint of left foot drop since the age of 46 years. Electromyography (EMG) and muscle biopsy from left tibialis anterior muscle were compatible with myopathy. Genetic analysis led to the identification of c.1714G>C/c.527A>T compound heterozygous mutation, which is the second most frequent mutation in Japan as far as we know. Previous research has revealed that c.1714G>C/c.527A>T compound heterozygous mutation is a mild mutation as the onset of the disease is much later than the usual age of onset of GNE myopathy and the clinical course is slowly progressive. This was the first case report in Korea of the clinicopathological characteristics of GNE myopathy with GNE (c.1714G>C/c.527A>T compound heterozygous) mutation.

Keyword

GNE myopathy; Hereditary inclusion body myopathy; Distal myopathy with rimmed vacuoles

MeSH Terms

Age of Onset
Biopsy
Electromyography
Female
Foot
Glucosamine
Humans
Japan
Korea
Middle Aged
Muscular Diseases
N-Acetylneuraminic Acid
Phosphotransferases
Glucosamine
N-Acetylneuraminic Acid
Phosphotransferases

Figure

• 

  Fig. 1 Diffuse fatty degeneration and atrophy of anterolateral compartment muscles of both lower legs. Low perifascial fluid dispersion with T2 high signal change at left tibialis anterior muscle is probably a previous biopsy related change. (A) Axial T1-weighted (upper) and T2-weighted (lower) spin-echo images, (B) pre-contrast (upper) and post-contrast (lower) liver acceleration volume acquisition images.

• 

  Fig. 2 (A) Immunohistochemical staining for desmin is negative. There is no accumulation except for only positive in regenerating myofibers. (B) Immunohistochemical staining for titin is positive. (C) Immunohistochemical staining for LDB3 (ZASP) is negative.

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  Fig. 3 Electropherogram of compound heterozygous mutations in this patient with GNE myopathy. (A) G-to-C transition at nucleotide position (c.1714G>C). (B) A-to-T transition at nucleotide position (c.527A>T).

Reference

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