rs121912938
Variant summary
Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PM1PM2PP3_StrongPP5_Very_Strong
The NM_001848.3(COL6A1):c.850G>A(p.Gly284Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).
Frequency
Consequence
NM_001848.3 missense
Scores
Clinical Significance
Conservation
Publications
- collagen 6-related myopathyInheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
- Bethlem myopathy 1AInheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P
- Ullrich congenital muscular dystrophy 1AInheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
- Bethlem myopathyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Ullrich congenital muscular dystrophyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
Genome browser will be placed here
ACMG classification
Our verdict: Pathogenic. The variant received 16 ACMG points.
Transcripts
RefSeq
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | MANE | Protein | UniProt |
|---|---|---|---|---|---|---|---|---|
| COL6A1 | NM_001848.3 | c.850G>A | p.Gly284Arg | missense_variant | Exon 9 of 35 | ENST00000361866.8 | NP_001839.2 |
Ensembl
| Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
|---|---|---|---|---|---|---|---|---|---|---|
| COL6A1 | ENST00000361866.8 | c.850G>A | p.Gly284Arg | missense_variant | Exon 9 of 35 | 1 | NM_001848.3 | ENSP00000355180.3 |
Frequencies
GnomAD3 genomes Cov.: 33
GnomAD2 exomes AF: 0.00 AC: 0AN: 246726 AF XY: 0.00
GnomAD4 exome Cov.: 31
GnomAD4 genome Cov.: 33
ClinVar
Submissions by phenotype
not provided Pathogenic:7
- -
Immunostaining of muscle biopsies in individuals who were heterozygous for this sequence change revealed sarcolemma-specific collagen VI deficiency (Kawahara et al., 2007); Located in a region intolerant to change (Glycine within the Gly-X-Y motif in the triple helical (TH) domain ); This variant is associated with the following publications: (PMID: 24271325, 29406609, 15689448, 32154989, 29465610, 30894207, 31127727, 16130093, 17785674, 18362356, 17215366, 24959844, 19564581, 24038877, 28918041, 29244830, 32065942, 32528171) -
- -
- -
- -
- -
- -
Ullrich congenital muscular dystrophy 1A Pathogenic:3Uncertain:1
- -
The observed variant c.850G>A (p.Gly284Arg) is not reported in 1000 Genomes and ExAC databases. The in silico prediction of the variant is disease causing by MutationTaster2, tolerated by SIFT, and probably damaging by PolyPhen2. -
PS1, PM1, PM2, PP3, PP5 -
- -
ULLRICH CONGENITAL MUSCULAR DYSTROPHY 1A, AUTOSOMAL DOMINANT Pathogenic:1
- -
Bethlem myopathy 1A Pathogenic:1
This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 284 of the COL6A1 protein (p.Gly284Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with autosomal dominant Ullrich congenital muscular dystrophy (UCMD) (PMID: 15689448, 16130093, 18825676, 19564581, 24038877, 24801232). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 17180). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt COL6A1 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects COL6A1 function (PMID: 17785674). This variant disrupts the triple helix domain of COL6A1. Glycine residues within the Gly-Xaa-Yaa repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). In COL6A1, variants at these glycine residues are significantly enriched in individuals with autosomal dominant disease (PMID: 15689448, 24038877) compared to the general population (ExAC). For these reasons, this variant has been classified as Pathogenic. -
Collagen 6-related myopathy Pathogenic:1
The COL6A1 c.850G>A (p.Gly284Arg) variant is a missense variant. Across a selection of the available literature, this variant has been identified in a heterozygous state in a total of 23 individuals with collagen 6-related myopathy encompassing a range of severity from early onset severe Ulrich congenital muscular dystrophy to the milder presentation of Bethlam myopathy (PMID: 24038877; 32154989; 34167565; 15689448). The variant occurred de novo in at least eight of these affected individuals. This variant is not found in version 2.1.1 or version 3.1.2 of the Genome Aggregation Database. The p.Gly284Arg variant lies within the triple helix domain disrupting a highly conserved Gly-Xaa-Yaa repeat motif (PMID: 20301676; 24038877). Multiple lines of computational evidence suggest the variant may impact the gene or gene product. Based on the collective evidence the c.850G>A (p.Gly284Arg) variant is classified as pathogenic for collagen 6-related myopathy. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at