Dataset Information

LGMD1D myopathy with cytoplasmic and nuclear inclusions in a Saudi family due to DNAJB6 mutation.

ABSTRACT: Autosomal dominant LGMD1D has been described in multiple families in Asia, Europe, and USA. However, to the best of our knowledge, no cases of LGMD1D have been reported among native Bedouin Saudi families. Fifty Saudi families with LGMD were analyzed and the causative underlying genes were studied utilizing genome wide linkage, homozygosity mapping, and neurological gene panel. We identified one family of a Bedouin origin with LGMD1D. Two patients had progressive proximal and distal weakness, dysphagia, and respiratory symptoms. Creatinine kinase was normal. Muscle biopsy showed marked variation in myofibers size with scattered angular atrophic fiber, necrotic fibers, and myophagocytosis, with red-rimmed vacuoles depicting a sarcoplasmic body. Heterozygous c.C287T (p.P96L) variant in exon 5 of DNAJB6 (NM_005494) gene was found. This change is localized within glycine and phenylalanine rich domain and alter an amino acid residue. Our findings will expand on the existing genotypic and phenotypic spectrum of this disorder and aid in elucidating hidden mechanisms implicated in LGMD1D.

SUBMITTER: Bohlega SA

PROVIDER: S-EPMC6390114 | biostudies-literature | 2018 Sep

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

LGMD1D myopathy with cytoplasmic and nuclear inclusions in a Saudi family due to DNAJB6 mutation.

Bohlega Saeed A SA Alfawaz Sarah S Abou-Al-Shaar Hussam H Al-Hindi Hindi N HN Murad Hatem N HN Bohlega Mohamed S MS Meyer Brian F BF Monies Dorota D

Acta myologica : myopathies and cardiomyopathies : official journal of the Mediterranean Society of Myology 20180901 3

Autosomal dominant LGMD1D has been described in multiple families in Asia, Europe, and USA. However, to the best of our knowledge, no cases of LGMD1D have been reported among native Bedouin Saudi families. Fifty Saudi families with LGMD were analyzed and the causative underlying genes were studied utilizing genome wide linkage, homozygosity mapping, and neurological gene panel. We identified one family of a Bedouin origin with LGMD1D. Two patients had progressive proximal and distal weakness, dy ...[more]

PMID: 30838352

Similar Datasets

Project description:IntroductionProtein aggregation is a common cause of neuropathology. The protein aggregation myopathy Limb-Girdle Muscular Dystrophy 1D (LGMD1D) is caused by mutations of amino acids Phe89 or Phe93 of DNAJB6, a co-chaperone of the HSP70 anti-aggregation protein. Another DNAJB6 mutation, Pro96Arg, was found to cause a distal-onset myopathy in one family.ResultsWe detail the mutational, neuropathological, neurophysiological, neurological and radiological features of five new DNAJB6-myopathy families. One has the known Phe93Leu mutation and classic late-onset slowly progressive LGMD1D. Two have different mutations of Phe91 causing a variant childhood-onset severe limb-girdle myopathy. One has a Phe100Val mutation and distal-onset myopathy, unique early bulbar involvement, and a gender-modified wide age-of-onset range. The last has childhood-onset severe distal-onset myopathy and the first non-missense DNAJB6 mutation, c.346 + 5G > A, causing a splicing defect that entirely eliminates DNAJB6's G/F domain (ΔG/F), the domain that harbours all other mutations. Clinical and imaging examinations reveal that muscles considered uninvolved in DNAJB6-myopathy, e.g. lateral gastrocnemii, are affected in our patients with new mutations. Mutational modelling based on the known structure of the bacterial DNAJ2 protein indicates that all past and present mutated residues cluster within 15 Å in the G/F domain and all disturb the interface of this domain with the protein's J domain that confers the interaction with HSP70.ConclusionsOur patients expand the phenotypic spectrum of DNAJB6-myopathy and allow tentative genotype-phenotype specifications. Combining with previous studies, the clinical severity spectrum is as follows: ΔG/F and Phe91 mutations, most severe; Phe100, Pro96, Phe89 mutations, intermediate; and Phe93, least severe. As it stands presently, proximal G/F domain mutations (Phe89, Phe91, Phe93) cause proximal limb-girdle myopathy, while distal G/F mutations (Pro96, Phe100) cause distal-onset myopathy. While all mutations affect the G/F-J interaction, each likely does so in different unknown extents or ways. One mutation, ΔG/F, causes its associated severe distal-onset myopathy phenotype in a clear way, through generation of a G/F domain-lacking DNAJB6 protein.

Dataset Information

LGMD1D myopathy with cytoplasmic and nuclear inclusions in a Saudi family due to DNAJB6 mutation.

Publications

LGMD1D myopathy with cytoplasmic and nuclear inclusions in a Saudi family due to DNAJB6 mutation.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets