rs777354703

Variant summary

Our verdict is Uncertain significance. The variant received 4 ACMG points: 4P and 0B. PM5PP3_Moderate

The NM_001849.4(COL6A2):​c.2810G>A​(p.Arg937Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000448 in 1,606,070 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R937W) has been classified as Likely pathogenic.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 34)
Exomes 𝑓: 0.000044 ( 0 hom. )

Consequence

COL6A2
NM_001849.4 missense

Scores

5
8
6

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:4

Conservation

PhyloP100: 9.17

Publications

1 publications found
Variant links:
Genes affected
COL6A2 (HGNC:2212): (collagen type VI alpha 2 chain) This gene encodes one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The product of this gene contains several domains similar to von Willebrand Factor type A domains. 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 this gene are associated with Bethlem myopathy and Ullrich scleroatonic muscular dystrophy. Three transcript variants have been identified for this gene. [provided by RefSeq, Jul 2008]
COL6A2 Gene-Disease associations (from GenCC):
  • collagen 6-related myopathy
    Inheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
  • Ullrich congenital muscular dystrophy 1B
    Inheritance: AR, AD Classification: DEFINITIVE Submitted by: G2P
  • Bethlem myopathy 1A
    Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
  • Ullrich congenital muscular dystrophy 1A
    Inheritance: AD, AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
  • Bethlem myopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Ullrich congenital muscular dystrophy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • myosclerosis
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 4 ACMG points.

PM5
Other missense variant is known to change same aminoacid residue: Variant chr21-46132301-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 287935.
PP3
MetaRNN computational evidence supports a deleterious effect, 0.848

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL6A2NM_001849.4 linkc.2810G>A p.Arg937Gln missense_variant Exon 28 of 28 ENST00000300527.9 NP_001840.3 P12110-1A0A384MDP3

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
COL6A2ENST00000300527.9 linkc.2810G>A p.Arg937Gln missense_variant Exon 28 of 28 1 NM_001849.4 ENSP00000300527.4 P12110-1

Frequencies

GnomAD3 genomes
AF:
0.0000526
AC:
8
AN:
152180
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000145
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000294
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000461
AC:
11
AN:
238568
AF XY:
0.0000459
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000117
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.0000566
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000366
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000440
AC:
64
AN:
1453890
Hom.:
0
Cov.:
34
AF XY:
0.0000359
AC XY:
26
AN XY:
723600
show subpopulations
African (AFR)
AF:
0.0000299
AC:
1
AN:
33430
American (AMR)
AF:
0.0000898
AC:
4
AN:
44566
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26058
East Asian (EAS)
AF:
0.0000252
AC:
1
AN:
39646
South Asian (SAS)
AF:
0.0000697
AC:
6
AN:
86072
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
46740
Middle Eastern (MID)
AF:
0.000174
AC:
1
AN:
5760
European-Non Finnish (NFE)
AF:
0.0000459
AC:
51
AN:
1111346
Other (OTH)
AF:
0.00
AC:
0
AN:
60272
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.504
Heterozygous variant carriers
0
5
10
15
20
25
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:
0.0000526
AC:
8
AN:
152180
Hom.:
0
Cov.:
34
AF XY:
0.0000942
AC XY:
7
AN XY:
74346
show subpopulations
African (AFR)
AF:
0.000145
AC:
6
AN:
41444
American (AMR)
AF:
0.00
AC:
0
AN:
15280
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5182
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10626
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000294
AC:
2
AN:
68024
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.444
Heterozygous variant carriers
0
1
2
2
3
4
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:
0.0000712
Hom.:
0
Bravo
AF:
0.0000869
ExAC
AF:
0.0000249
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:4
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:3
Jun 06, 2017
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

A variant of uncertain significance has been identified in the COL6A2 gene. The R937Q variant has been reported previously in an individual with Bethlem myopathy who had two other COL6A2 variants identified; however, parental testing was not completed (Stehikova et al., 2016). The R937Q variant is not observed at a significant frequency in large population cohorts (Lek et al., 2016; 1000 Genomes Consortium et al., 2015; Exome Variant Server). The R937Q variant is a semi-conservative amino acid substitution, which may impact secondary protein structure as these residues differ in some properties. This substitution occurs at a position that is conserved across species. In silico analysis is inconsistent in its predictions as to whether or not the variant is damaging to the protein structure/function. Therefore, based on the currently available information, it is unclear whether this variant is a pathogenic variant or a rare benign variant. -

Jul 31, 2015
Eurofins Ntd Llc (ga)
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Dec 28, 2020
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Bethlem myopathy 1A Uncertain:1
Nov 29, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 937 of the COL6A2 protein (p.Arg937Gln). This variant is present in population databases (rs777354703, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with COL6A2-related conditions. ClinVar contains an entry for this variant (Variation ID: 282183). 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) has been performed for this missense variant. However, the output from this modeling did not meet the statistical confidence thresholds required to predict the impact of this variant on COL6A2 protein function. This variant disrupts the p.Arg937 amino acid residue in COL6A2. Other variant(s) that disrupt this residue have been determined to be pathogenic (PMID: 30564623; internal data). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.69
BayesDel_addAF
Uncertain
0.025
T
BayesDel_noAF
Uncertain
0.020
CADD
Pathogenic
27
DANN
Uncertain
0.99
DEOGEN2
Benign
0.37
T
Eigen
Uncertain
0.57
Eigen_PC
Uncertain
0.45
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.83
T
M_CAP
Pathogenic
0.59
D
MetaRNN
Pathogenic
0.85
D
MetaSVM
Uncertain
0.73
D
MutationAssessor
Uncertain
2.6
M
PhyloP100
9.2
PrimateAI
Uncertain
0.63
T
PROVEAN
Benign
-1.3
N
REVEL
Pathogenic
0.68
Sift
Benign
0.084
T
Sift4G
Benign
0.21
T
Polyphen
1.0
D
Vest4
0.61
MVP
0.98
MPC
0.65
ClinPred
0.34
T
GERP RS
4.2
Varity_R
0.13
gMVP
0.86
Mutation Taster
=48/52
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: rs777354703; hg19: chr21-47552216; COSMIC: COSV99384728; COSMIC: COSV99384728; API