21-46118626-C-T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4BP6

The NM_001849.4(COL6A2):​c.1129C>T​(p.Arg377Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000124 in 1,612,378 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts 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. R377H) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00015 ( 0 hom., cov: 34)
Exomes 𝑓: 0.00012 ( 0 hom. )

Consequence

COL6A2
NM_001849.4 missense

Scores

5
10
3

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:3

Conservation

PhyloP100: 0.924

Publications

2 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: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.2920601).
BP6
Variant 21-46118626-C-T is Benign according to our data. Variant chr21-46118626-C-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 285233.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001849.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
COL6A2
NM_001849.4
MANE Select
c.1129C>Tp.Arg377Cys
missense
Exon 13 of 28NP_001840.3
COL6A2
NM_058174.3
MANE Plus Clinical
c.1129C>Tp.Arg377Cys
missense
Exon 13 of 28NP_478054.2
COL6A2
NM_058175.3
c.1129C>Tp.Arg377Cys
missense
Exon 13 of 28NP_478055.2

Ensembl Transcripts

Selected
GeneTranscriptTagsHGVScHGVSpEffectExon RankProteinUniProt
COL6A2
ENST00000300527.9
TSL:1 MANE Select
c.1129C>Tp.Arg377Cys
missense
Exon 13 of 28ENSP00000300527.4
COL6A2
ENST00000397763.6
TSL:5 MANE Plus Clinical
c.1129C>Tp.Arg377Cys
missense
Exon 13 of 28ENSP00000380870.1
COL6A2
ENST00000409416.6
TSL:5
c.1129C>Tp.Arg377Cys
missense
Exon 12 of 27ENSP00000387115.1

Frequencies

GnomAD3 genomes
AF:
0.000151
AC:
23
AN:
152216
Hom.:
0
Cov.:
34
show subpopulations
Gnomad AFR
AF:
0.000434
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.0000654
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:
0.0000588
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.000364
AC:
90
AN:
247534
AF XY:
0.000260
show subpopulations
Gnomad AFR exome
AF:
0.000317
Gnomad AMR exome
AF:
0.00232
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000449
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.000121
AC:
177
AN:
1460162
Hom.:
0
Cov.:
32
AF XY:
0.0000909
AC XY:
66
AN XY:
726350
show subpopulations
African (AFR)
AF:
0.000358
AC:
12
AN:
33480
American (AMR)
AF:
0.00201
AC:
90
AN:
44686
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26108
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39684
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86114
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
52148
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.0000612
AC:
68
AN:
1111828
Other (OTH)
AF:
0.000116
AC:
7
AN:
60346
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.464
Heterozygous variant carriers
0
10
19
29
38
48
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
10
20
30
40
50
<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:
0.000151
AC:
23
AN:
152216
Hom.:
0
Cov.:
34
AF XY:
0.0000941
AC XY:
7
AN XY:
74364
show subpopulations
African (AFR)
AF:
0.000434
AC:
18
AN:
41466
American (AMR)
AF:
0.0000654
AC:
1
AN:
15290
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5186
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4832
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10624
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000588
AC:
4
AN:
68026
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.516
Heterozygous variant carriers
0
1
3
4
6
7
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:
0.000772
Hom.:
0
Bravo
AF:
0.000298
ESP6500AA
AF:
0.000455
AC:
2
ESP6500EA
AF:
0.00
AC:
0
ExAC
AF:
0.000372
AC:
45
EpiCase
AF:
0.000109
EpiControl
AF:
0.00

ClinVar

Significance: Conflicting classifications of pathogenicity
Submissions summary: Uncertain:2Benign:3
Revision: criteria provided, conflicting classifications
LINK: link

Submissions by phenotype

not provided Uncertain:2
Feb 23, 2024
GeneDx
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Observed in an individual with Emery-Dreifuss muscular dystrophy in the published literature; a second COL6A2 variant was not reported (PMID: 20576434); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 23040494, 30564623, 29950560, 20576434)

Apr 25, 2023
Revvity Omics, Revvity
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

not specified Benign:1
Jun 20, 2016
Eurofins Ntd Llc (ga)
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

Bethlem myopathy 1A Benign:1
Aug 08, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Likely benign
Review Status:criteria provided, single submitter
Collection Method:clinical testing

COL6A2-related disorder Benign:1
Oct 31, 2022
PreventionGenetics, part of Exact Sciences
Significance:Likely benign
Review Status:no assertion criteria provided
Collection Method:clinical testing

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications).

Computational scores

Source: dbNSFP v4.9

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Uncertain
0.56
BayesDel_addAF
Benign
-0.032
T
BayesDel_noAF
Pathogenic
0.18
CADD
Pathogenic
32
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.64
D
Eigen
Uncertain
0.49
Eigen_PC
Uncertain
0.48
FATHMM_MKL
Uncertain
0.92
D
LIST_S2
Pathogenic
0.97
D
M_CAP
Pathogenic
0.61
D
MetaRNN
Benign
0.29
T
MetaSVM
Pathogenic
0.82
D
MutationAssessor
Benign
1.6
L
PhyloP100
0.92
PrimateAI
Uncertain
0.58
T
PROVEAN
Uncertain
-3.6
D
REVEL
Pathogenic
0.76
Sift
Uncertain
0.012
D
Sift4G
Uncertain
0.031
D
Polyphen
1.0
D
Vest4
0.70
MVP
0.93
MPC
0.71
ClinPred
0.10
T
GERP RS
4.7
Varity_R
0.36
gMVP
0.60
Mutation Taster
=33/67
disease causing

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs144801620; hg19: chr21-47538540; COSMIC: COSV56001091; COSMIC: COSV56001091; API