Abstract
Introduction: Nemaline myopathy (NEM) is a heterogeneous muscle disease, which usually presents with hypotonia and muscle weakness. Biallelic pathogenic variants of KLHL40 gene cause severe form of NEM (NEM8), which leads to a wide range of symptoms, including hypotonia, muscle weakness, joint contractures and fractures. Nemaline bodies in muscle fiber are characteristic findings of the disease. Case Presentation: Here, we presented three affected individuals in a family with variable phenotypes, in whom the same novel splice-site variant in KLHL40 gene (c.1607+3A>T) was detected. Discussion: This study expanded the spectrum of genotype and phenotype of NEM8, and emphasized that molecular genetic tests are highly valuable in diagnosis of patients with inconclusive muscle biopsy results.
Journal Section:
Novel Insights from Clinical Practice
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