rs112172548

Variant summary

Our verdict is Likely benign. The variant received -1 ACMG points: 0P and 1B. BP4

The NM_004369.4(COL6A3):​c.2864G>A​(p.Arg955His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000731 in 1,614,122 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R955C) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000072 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000073 ( 0 hom. )

Consequence

COL6A3
NM_004369.4 missense

Scores

2
2
15

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 0.158

Publications

5 publications found
Variant links:
Genes affected
COL6A3 (HGNC:2213): (collagen type VI alpha 3 chain) This gene encodes the alpha-3 chain, one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The alpha-3 chain of type VI collagen is much larger than the alpha-1 and -2 chains. This difference in size is largely due to an increase in the number of subdomains, similar to von Willebrand Factor type A domains, that are found in the amino terminal globular domain of all the alpha chains. These domains have been shown to bind extracellular matrix proteins, an interaction that explains the importance of this collagen in organizing matrix components. Mutations in the type VI collagen genes are associated with Bethlem myopathy, a rare autosomal dominant proximal myopathy with early childhood onset. Mutations in this gene are also a cause of Ullrich congenital muscular dystrophy, also referred to as Ullrich scleroatonic muscular dystrophy, an autosomal recessive congenital myopathy that is more severe than Bethlem myopathy. Multiple transcript variants have been identified, but the full-length nature of only some of these variants has been described. [provided by RefSeq, Jun 2009]
COL6A3 Gene-Disease associations (from GenCC):
  • Bethlem myopathy 1A
    Inheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics
  • collagen 6-related myopathy
    Inheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
  • Ullrich congenital muscular dystrophy 1C
    Inheritance: AR Classification: DEFINITIVE Submitted by: G2P
  • dystonia 27
    Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Illumina, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics, Orphanet
  • Ullrich congenital muscular dystrophy 1A
    Inheritance: AR, AD, SD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
  • Bethlem myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Ullrich congenital muscular dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -1 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.34483832).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL6A3NM_004369.4 linkc.2864G>A p.Arg955His missense_variant Exon 7 of 44 ENST00000295550.9 NP_004360.2 P12111-1D9ZGF2Q8N4Z1Q63HQ4

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL6A3ENST00000295550.9 linkc.2864G>A p.Arg955His missense_variant Exon 7 of 44 1 NM_004369.4 ENSP00000295550.4 P12111-1

Frequencies

GnomAD3 genomes
AF:
0.0000723
AC:
11
AN:
152228
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000724
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.000192
Gnomad SAS
AF:
0.000207
Gnomad FIN
AF:
0.0000942
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000735
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000716
AC:
18
AN:
251458
AF XY:
0.0000736
show subpopulations
Gnomad AFR exome
AF:
0.0000615
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000544
Gnomad FIN exome
AF:
0.0000462
Gnomad NFE exome
AF:
0.000106
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000732
AC:
107
AN:
1461894
Hom.:
0
Cov.:
32
AF XY:
0.0000811
AC XY:
59
AN XY:
727248
show subpopulations
African (AFR)
AF:
0.0000597
AC:
2
AN:
33480
American (AMR)
AF:
0.0000447
AC:
2
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.0000232
AC:
2
AN:
86258
European-Finnish (FIN)
AF:
0.0000749
AC:
4
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000827
AC:
92
AN:
1112012
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
9
17
26
34
43
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
4
8
12
16
20
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000723
AC:
11
AN:
152228
Hom.:
0
Cov.:
33
AF XY:
0.0000941
AC XY:
7
AN XY:
74370
show subpopulations
African (AFR)
AF:
0.0000724
AC:
3
AN:
41458
American (AMR)
AF:
0.00
AC:
0
AN:
15284
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3470
East Asian (EAS)
AF:
0.000192
AC:
1
AN:
5206
South Asian (SAS)
AF:
0.000207
AC:
1
AN:
4826
European-Finnish (FIN)
AF:
0.0000942
AC:
1
AN:
10618
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000735
AC:
5
AN:
68044
Other (OTH)
AF:
0.00
AC:
0
AN:
2094
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.520
Heterozygous variant carriers
0
1
2
4
5
6
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.000122
Hom.:
0
Bravo
AF:
0.0000529
TwinsUK
AF:
0.00
AC:
0
ALSPAC
AF:
0.000259
AC:
1
ESP6500AA
AF:
0.000227
AC:
1
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.0000906
AC:
11
EpiCase
AF:
0.000218
EpiControl
AF:
0.000237

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:5Benign:1
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:3
Dec 19, 2016
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Nov 04, 2021
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in a patient reported to have intermediate collagen VI-related myopathy who harbored a second variant in the COL6A3 gene, however, it is unclear if comprehensive genetic testing was completed (Foley et al., 2013); In silico analysis, which includes protein predictors and evolutionary conservation, supports that this variant does not alter protein structure/function; This variant is associated with the following publications: (PMID: 24271325) -

Apr 20, 2022
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

not specified Uncertain:1
Jul 15, 2024
Women's Health and Genetics/Laboratory Corporation of America, LabCorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Variant summary: COL6A3 c.2864G>A (p.Arg955His) results in a non-conservative amino acid change located in the von Willebrand factor, type A domain (IPR002035) of the encoded protein sequence. Four of five in-silico tools predict a benign effect of the variant on protein function. The variant allele was found at a frequency of 7.2e-05 in 251458 control chromosomes, predominantly at a frequency of 0.00011 within the Non-Finnish European subpopulation in the gnomAD database. This frequency is not significantly higher than estimated for a pathogenic variant in COL6A3 causing Ullrich Congenital Muscular Dystrophy 1, allowing no conclusion about variant significance. c.2864G>A has been reported in the literature in one individual affected with collagen VI-related myopathy, without strong evidence for causality (Foley_2013). These report(s) do not provide unequivocal conclusions about association of the variant with Ullrich Congenital Muscular Dystrophy 1. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 24271325). ClinVar contains an entry for this variant (Variation ID: 283020). Based on the evidence outlined above, the variant was classified as uncertain significance. -

Collagen 6-related myopathy Uncertain:1
Oct 19, 2020
Victorian Clinical Genetics Services, Murdoch Childrens Research Institute
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Based on the classification scheme VCGS_Germline_v1.3.3, this variant is classified as VUS - 3C. Following criteria are met: 0103 - Dominant negative and loss of function are known mechanisms of disease in this gene and are associated with Dystonia 27 (MIM# 616411). Missense variants affecting a glycine residue within a Gly-X-Y triple helical repeat have a dominant negative mechanism, while other missense and protein-truncating variants result in loss of function (OMIM, GeneReviews). (I) 0108 - This gene is associated with both recessive and dominant disease. All dominant forms of disease are caused by variants with a dominant negative mechanism, while recessive disease is caused by loss of function variants (PMID: 20976770; PMID: 15563506). (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to histidine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (22 heterozygotes, 0 homozygotes). (SP) 0503 - Missense variant consistently predicted to be tolerated by multiple in silico tools or not conserved in placental mammals with a minor amino acid change. (SB) 0600 - Variant is located in the annotated vWFA domain (PDB, NCBI). (I) 0710 - Another missense variant comparable to the one identified in this case has inconclusive previous evidence for pathogenicity. The p.Arg955Cys variant has been reported as a VUS in ClinVar, and in a patient with limb girdle muscular dystrophy (PMID: 30564623). (I) 0808 - Previous reports of pathogenicity for this variant are conflicting. This variant has been reported as a VUS (ClinVar) and in a patient with intermediate collagen VI myopathy (PMID: 24271325). (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Bethlem myopathy 1A Benign:1
Nov 29, 2023
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Benign
0.079
BayesDel_addAF
Benign
-0.25
T
BayesDel_noAF
Benign
-0.38
CADD
Benign
15
DANN
Uncertain
1.0
DEOGEN2
Benign
0.16
.;T;.;T;.;.;.
Eigen
Benign
-0.56
Eigen_PC
Benign
-0.63
FATHMM_MKL
Benign
0.032
N
LIST_S2
Uncertain
0.88
D;D;D;D;.;T;T
M_CAP
Pathogenic
0.47
D
MetaRNN
Benign
0.34
T;T;T;T;T;T;T
MetaSVM
Benign
-0.56
T
MutationAssessor
Benign
-0.16
.;N;.;.;.;.;.
PhyloP100
0.16
PrimateAI
Benign
0.25
T
PROVEAN
Benign
-0.59
N;N;N;.;N;N;N
REVEL
Pathogenic
0.72
Sift
Benign
0.15
T;T;T;.;T;T;T
Sift4G
Benign
0.083
T;D;T;T;T;T;T
Polyphen
1.0
D;B;.;.;D;.;.
Vest4
0.062
MVP
0.78
MPC
0.21
ClinPred
0.96
D
GERP RS
2.6
Varity_R
0.031
gMVP
0.38
Mutation Taster
=2/98
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.0
Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

Other links and lift over

dbSNP: rs112172548; hg19: chr2-238285621; COSMIC: COSV55094037; COSMIC: COSV55094037; API