2-237379103-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2PM5PP3_Strong

The NM_004369.4(COL6A3):​c.2030G>T​(p.Arg677Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000173 in 1,614,066 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. R677H) has been classified as Benign.

Frequency

Genomes: 𝑓 0.000013 ( 0 hom., cov: 33)
Exomes 𝑓: 0.000018 ( 0 hom. )

Consequence

COL6A3
NM_004369.4 missense

Scores

12
5
2

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 2.69
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]

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PM5
Other missense variant is known to change same aminoacid residue: Variant chr2-237379103-C-T is described in Lovd as [Likely_pathogenic].
PP3
MetaRNN computational evidence supports a deleterious effect, 0.987

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
COL6A3NM_004369.4 linkc.2030G>T p.Arg677Leu missense_variant Exon 6 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.2030G>T p.Arg677Leu missense_variant Exon 6 of 44 1 NM_004369.4 ENSP00000295550.4 P12111-1

Frequencies

GnomAD3 genomes
AF:
0.0000131
AC:
2
AN:
152178
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.00
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
GnomAD3 exomes
AF:
0.00000796
AC:
2
AN:
251346
Hom.:
0
AF XY:
0.0000147
AC XY:
2
AN XY:
135862
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad SAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.0000178
AC:
26
AN:
1461888
Hom.:
0
Cov.:
33
AF XY:
0.0000165
AC XY:
12
AN XY:
727244
show subpopulations
Gnomad4 AFR exome
AF:
0.00
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.0000765
Gnomad4 EAS exome
AF:
0.00
Gnomad4 SAS exome
AF:
0.00
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.0000216
Gnomad4 OTH exome
AF:
0.00
GnomAD4 genome
AF:
0.0000131
AC:
2
AN:
152178
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74338
show subpopulations
Gnomad4 AFR
AF:
0.00
Gnomad4 AMR
AF:
0.00
Gnomad4 ASJ
AF:
0.00
Gnomad4 EAS
AF:
0.00
Gnomad4 SAS
AF:
0.00
Gnomad4 FIN
AF:
0.00
Gnomad4 NFE
AF:
0.0000294
Gnomad4 OTH
AF:
0.00
Bravo
AF:
0.0000264

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

not provided Uncertain:2
Dec 27, 2019
Revvity Omics, Revvity
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Jun 01, 2016
Eurofins Ntd Llc (ga)
Significance: Uncertain significance
Review Status: criteria provided, single submitter
Collection Method: clinical testing

- -

Bethlem myopathy 1A Uncertain:1
Mar 17, 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 leucine, which is neutral and non-polar, at codon 677 of the COL6A3 protein (p.Arg677Leu). This variant is present in population databases (rs35227432, gnomAD 0.0009%). This variant has not been reported in the literature in individuals affected with COL6A3-related conditions. ClinVar contains an entry for this variant (Variation ID: 288417). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt COL6A3 protein function with a negative predictive value of 95%. 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
Uncertain
0.38
BayesDel_addAF
Pathogenic
0.40
D
BayesDel_noAF
Pathogenic
0.34
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Uncertain
0.68
.;D;.;.;.
Eigen
Pathogenic
0.77
Eigen_PC
Pathogenic
0.71
FATHMM_MKL
Pathogenic
0.97
D
LIST_S2
Uncertain
0.90
D;D;.;D;D
M_CAP
Pathogenic
0.41
D
MetaRNN
Pathogenic
0.99
D;D;D;D;D
MetaSVM
Pathogenic
0.82
D
MutationAssessor
Pathogenic
3.1
.;M;.;.;.
PrimateAI
Benign
0.36
T
PROVEAN
Pathogenic
-6.0
D;D;D;D;D
REVEL
Pathogenic
0.80
Sift
Uncertain
0.0020
D;D;D;D;D
Sift4G
Pathogenic
0.0
D;D;D;D;D
Polyphen
1.0
D;D;D;.;.
Vest4
0.91
MutPred
0.94
.;Gain of sheet (P = 0.1208);.;.;.;
MVP
0.95
MPC
0.72
ClinPred
0.99
D
GERP RS
5.5
Varity_R
0.73
gMVP
0.78

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Other links and lift over

dbSNP: rs35227432; hg19: chr2-238287746; API