scholarly journals Compound heterozygous c.598_612del and c.1746-20C > G CAPN3 genotype cause autosomal recessive limb-girdle muscular dystrophy-1: a case report

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Evelina Siavrienė ◽  
Gunda Petraitytė ◽  
Birutė Burnytė ◽  
Aušra Morkūnienė ◽  
Violeta Mikštienė ◽  
...  
Keyword(s):  
Muscular Dystrophy ◽  
Autosomal Recessive ◽  
Premature Termination Codon ◽  
Limb Girdle Muscular Dystrophy ◽  
Lower Limbs ◽  
Compound Heterozygous ◽  
Targeted Next Generation Sequencing ◽  
Splicing Variant ◽  
Cdna Analysis ◽  
Compound Heterozygous Variants

Abstract Background Autosomal recessive limb–girdle muscular dystrophy-1 (LGMDR1), also known as calpainopathy, is a genetically heterogeneous disorder characterised by progression of muscle weakness. Homozygous or compound heterozygous variants in the CAPN3 gene are known genetic causes of this condition. The aim of this study was to confirm the molecular consequences of the CAPN3 variant NG_008660.1(NM_000070.3):c.1746-20C > G of an individual with suspected LGMDR1 by extensive complementary DNA (cDNA) analysis. Case presentation In the present study, we report on a male with proximal muscular weakness in his lower limbs. Compound heterozygous NM_000070.3:c.598_612del and NG_008660.1(NM_000070.3):c.1746-20C > G genotype was detected on the CAPN3 gene by targeted next-generation sequencing (NGS). To confirm the pathogenicity of the variant c.1746-20C > G, we conducted genetic analysis based on Sanger sequencing of the proband’s cDNA sample. The results revealed that this splicing variant disrupts the original 3′ splice site on intron 13, thus leading to the skipping of the DNA fragment involving exon 14 and possibly exon 15. However, the lack of exon 15 in the CAPN3 isoforms present in a blood sample was explained by cell-specific alternative splicing rather than an aberrant splicing mechanism. In silico the c.1746-20C > G splicing variant consequently resulted in frameshift and formation of a premature termination codon (NP_000061.1:p.(Glu582Aspfs*62)). Conclusions Based on the results of our study and the literature we reviewed, both c.598_612del and c.1746-20C > G variants are pathogenic and together cause LGMDR1. Therefore, extensive mRNA and/or cDNA analysis of splicing variants is critical to understand the pathogenesis of the disease.

scholarly journals A case of pseudodominant inheritance of limb-girdle muscular dystrophy caused by mutations in the CAPN3 gene

2021 ◽  
Vol 15 (3) ◽  
pp. 85-91
Author(s):  
Inna V. Sharkova ◽  
Maria V. Bulakh ◽  
Liudmila А. Bessonova ◽  
Olga A. Shchagina ◽  
Elena L. Dadaly
Keyword(s):  
Muscular Dystrophy ◽  
Autosomal Recessive ◽  
Autosomal Recessive Disease ◽  
Disease Onset ◽  
Limb Girdle Muscular Dystrophy ◽  
Compound Heterozygous ◽  
Carrier Status ◽  
Heterozygous Carrier ◽  
Calpain 3 ◽  
Capn3 Gene

Introduction. Limb-girdle muscular dystrophy (LGMD) includes more than 30 forms caused by mutations in genes located on autosomes. The most common form is calpain-3-related LGMD, with autosomal recessive inheritance pattern (OMIM 253600). An autosomal dominant form of LGMD (OMIM 618129) caused by c.643_663del heterozygous mutation in the CAPN3 gene is also supposed to exist. This article describes a family case of LGMD caused by mutations in the CAPN3 gene with pseudodominant inheritance. Materials and methods. Two patients with LGMD were studied: a 59-year-old woman and her 38-year-old daughter. Clinical, genealogical and molecular genetics methods were used: limb girdle muscular dystrophy MPS panel, Sanger sequencing of DNA of the proband, her affected daughter, and six first- and second-degree relatives across four generations. Results. It was found that identical variants of the nucleotide sequence, c.598_612del and c.1746-20CG, identified in the CAPN3 gene of the proband and her daughter, are in the trans position (compound heterozygous state), causing autosomal recessive calpain-3-related LGMD. This is an example of an incredibly rare pseudodominant inheritance of an autosomal recessive disease, established through indirect evidence that the probands husband is a heterozygous carrier of a nucleotide substitution in the CAPN3 gene. Conclusion. It is crucial to examine the marriage partner for heterozygous carrier status of a gene mutation responsible for the disease in family planning and when clarifying the childs prognosis for a patient with an autosomal recessive disease. Considering the existence of a late-onset (after 30 years) LGMD phenotype associated with the CAPN3 gene, differential diagnosis should begin with testing this gene in families with late disease onset.

scholarly journals A case report: autosomal recessive limb girdle muscular dystrophy caused by a novel mutation (c. 287A > G) in POMT2 gene of a Chinese Han patient

2019 ◽  
Author(s):  
Yanlu Gao ◽  
Zhixia Kang ◽  
Xiaojing Wei ◽  
Jing Miao ◽  
Xuefan Yu
Keyword(s):  
Creatine Kinase ◽  
Cognitive Impairment ◽  
Case Report ◽  
Muscular Dystrophy ◽  
Muscle Weakness ◽  
Autosomal Recessive ◽  
Limb Girdle Muscular Dystrophy ◽  
Compound Heterozygous ◽  
Proximal Muscle Weakness ◽  
Proximal Muscle

Abstract BACKGROUND Autosomal recessive limb girdle muscular dystrophy 2N is caused by mutations in the POMT2 gene. The disease is characterized by proximal muscle weakness,with minimal progression, with cognitive impairment,a significantly elevated serum level of creatine kinase. CASE PRESENTATION A 9-year-old boy presented with proximal muscle weakness since the last 4 years,with minimal progression.There was no significant family history.Medical examination showed no generalized muscle hypertrophy. Serum creatine kinase level was 52-fold higher than the normal value. Wechsler Intelligence scale for Children (WISC, 4) suggested mild cognitive impairment (IQ =74). DNA sequence analysis identified a novel missense mutation (c. 287A > G) and a known mutation (c. 1261C > T). CONCLUSIONS This case report of autosomal recessive limb girdle muscular dystrophy 2N caused by a novel compound heterozygous mutation expands the genotypic spectrum of POMT2 gene.

scholarly journals A novel LOXHD1 variant in a Chinese couple with hearing loss

2019 ◽  
Vol 47 (12) ◽  
pp. 6082-6090 ◽  
Author(s):  
Chuan Zhang ◽  
Shengju Hao ◽  
Yali Liu ◽  
Bingbo Zhou ◽  
Furong Liu ◽  
...  
Keyword(s):  
Hearing Loss ◽  
Molecular Diagnosis ◽  
Protein Function ◽  
Mexican American ◽  
Compound Heterozygous ◽  
Congenital Hearing Loss ◽  
Targeted Next Generation Sequencing ◽  
Novel Variants ◽  
Novel Variant ◽  
Compound Heterozygous Variants

Objective To perform molecular diagnosis and genetic counseling in a young Chinese couple with congenital hearing loss. Methods Variant screening analysis was performed by PCR and direct Sanger sequencing or targeted next-generation sequencing of all known hearing loss genes. Novel variants were evaluated by PolyPhen2 and PROVEAN software tools to evaluate possible effects on protein function. Results We identified causative variants in the young couple: c.235delC (rs80338943)/c.299-300delAT (rs111033204) compound heterozygous variants of GJB2 in the husband and c.1828G>A (p.Glu610Lys, rs535637788)/c.2825-2827delAGA compound heterozygous variants of LOXHD1 in the wife. The LOXHD1 c.1828G>A variant has only previously been reported in a Mexican-American individual in the 1000 Genomes Project database. Using PolyPhen2 and PROVEAN, we speculated that the LOXHD1 variant c.1828G>A is potentially pathogenic. Conclusion We carried out molecular diagnosis in a young couple with congenital hearing loss, and identified different disease-causing genes in the two individuals. The LOXHD1 variant c.1828G>A present in the wife had not previously been reported in individuals with congenital hearing loss. We determined this to be a potential pathogenic variant, and a novel variant associated with hearing loss in a Chinese individual.

Sign in / Sign up

Export Citation Format

Share Document