Ann Clin Neurophysiol.  2020 Apr;22(1):29-32. 10.14253/acn.2020.22.1.29.

LGMD2E with a novel nonsense variantin SGCB gene: a case of LGMD2E with anovel variant

• La YK
• Oh EK
• Lyou HJ
• Hong JM
• Choi YC

• KMID: 2500301
• DOI: http://doi.org/10.14253/acn.2020.22.1.29

Abstract

Sarcoglycanopathies are a rare group of autosomal recessive limb-girdle muscular dystrophies (LGMDs) caused by genetic variants in α-, β-, γ-, or δ-sarcoglycan that maintain membrane integrity and contribute to molecular signal processing. High-throughput nucleotide sequencing was performed in patients with slowly progressive proximal muscle weakness from early childhood with respiratory involvement, which detected a novel homozygous nonsense variant (c.601C>T;p.Gln201Ter) in SGCB. This report informs about the clinical characteristics of LGMD2E (type-2E LGMD) in Korea and provides genetic confirmation of the disease.

Keyword

High-throughput nucleotide sequencing; Sarcoglycanopathies; SGCB

Figure

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  Fig. 1. Pedigree and sequencing chromatogram of the patients with limb-girdle muscular dystrophy. (A) The family pedigree: males (squares), females (circles), affected individuals (filled symbols), unaffected individuals (open symbols). The proband (II-8, black arrow) and the younger sibling (II-9, gray arrow) had a clinical presentation of childhood muscular dystrophy. (B) Sanger sequencing chromatogram of the SGCB variant in the proband. The cDNA sequence with a homozygous C-to-T substitution in exon 4 (red arrow) was predicted to terminate transcription and produce a truncated β-sarcoglycan protein.

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