Abdullah Sezer, Afife Büke, Hasan Hüseyin Kazan, Ahmet Kablan, Mustafa Tarık Alay, Beril Talim, Deniz Yüksel, Hanife Saat
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引用次数: 0
Abstract
Sarcoglycanopathies are autosomal recessive muscular dystrophies characterized by progressive muscle weakness and represent a major subset of limb-girdle muscular dystrophies (LGMDs). They result from pathogenic variants in sarcoglycan genes (SGCA, SGCB, SGCD, and SGCG), which encode subunits of a tetrameric transmembrane complex that stabilizes the dystrophin-associated glycoprotein complex. Among these, SGCG is commonly affected and is associated with LGMD2C/R5. Several founder variants in SGCG have been reported across different populations. Here, we describe a novel founder allele in the Turkish population, comprising a missense variant (c.392A>G, p.Lys131Arg) and a copy number gain (exon 1-4 duplication) that occurs in cis. Through an inductive screening strategy, we identified these linked variants in 11 individuals: five affected patients from four families and six unrelated incidental carriers. Haplotype analysis confirmed a shared genomic background supporting a founder effect. Affected individuals carried the allele in a homozygous or compound heterozygous state with other pathogenic SGCG variants. Molecular and histopathological investigations revealed that the duplicated allele results in mRNA decay and loss of SGCG protein expression. This study represents the first report of a disease-associated duplication in SGCG, highlighting a novel founder allele composed of two linked variants that contribute to sarcoglycanopathy in a specific population.
期刊介绍:
Clinical Genetics links research to the clinic, translating advances in our understanding of the molecular basis of genetic disease for the practising clinical geneticist. The journal publishes high quality research papers, short reports, reviews and mini-reviews that connect medical genetics research with clinical practice.
Topics of particular interest are:
• Linking genetic variations to disease
• Genome rearrangements and disease
• Epigenetics and disease
• The translation of genotype to phenotype
• Genetics of complex disease
• Management/intervention of genetic diseases
• Novel therapies for genetic diseases
• Developmental biology, as it relates to clinical genetics
• Social science research on the psychological and behavioural aspects of living with or being at risk of genetic disease