2-237366861-C-A

Position:

chr2-237366861-C-A

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM1PM2PP3_Strong

The NM_004369.4(COL6A3):c.5326G>T(p.Val1776Phe) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000105 in 1,614,144 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 (★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 33)

Exomes 𝑓: 0.0000089 ( 0 hom. )

Consequence

COL6A3
NM_004369.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 3.35

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 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

PM1

In a domain VWFA 9 (size 173) in uniprot entity CO6A3_HUMAN there are 7 pathogenic changes around while only 2 benign (78%) in NM_004369.4

PM2

Very rare variant in population databases, with high coverage;

PP3

MetaRNN computational evidence supports a deleterious effect, 0.968

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL6A3	NM_004369.4 link	c.5326G>T	p.Val1776Phe	missense_variant	11/44	ENST00000295550.9	NP_004360.2	P12111-1D9ZGF2Q8N4Z1Q63HQ4
COL6A3	NM_057167.4 link	c.4708G>T	p.Val1570Phe	missense_variant	10/43		NP_476508.2	P12111-2Q8N4Z1Q63HQ4
COL6A3	NM_057166.5 link	c.3505G>T	p.Val1169Phe	missense_variant	8/41		NP_476507.3	P12111-4B7ZW00

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
COL6A3	ENST00000295550.9 link	c.5326G>T	p.Val1776Phe	missense_variant	11/44	1	NM_004369.4	ENSP00000295550.4	P12111-1
COL6A3	ENST00000472056.5 link	c.3505G>T	p.Val1169Phe	missense_variant	8/41	1		ENSP00000418285.1	P12111-4
COL6A3	ENST00000353578.9 link	c.4708G>T	p.Val1570Phe	missense_variant	10/43	5		ENSP00000315873.4	P12111-2

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152250

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000482

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:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000119

AC:

AN:

251486

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135914

show subpopulations

Gnomad AFR exome

AF:

0.0000615

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:

0.00000889

AC:

AN:

1461894

Hom.:

Cov.:

AF XY:

0.00000825

AC XY:

AN XY:

727248

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000108

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152250

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74390

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000227

ExAC

AF:

0.0000165

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Bethlem myopathy 1A

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 11, 2023

This sequence change replaces valine, which is neutral and non-polar, with phenylalanine, which is neutral and non-polar, at codon 1776 of the COL6A3 protein (p.Val1776Phe). This variant is present in population databases (rs754788931, gnomAD 0.007%). 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. 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) has been performed at Invitae 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 COL6A3 protein function. ClinVar contains an entry for this variant (Variation ID: 476534). This variant has not been reported in the literature in individuals affected with COL6A3-related conditions. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.62

BayesDel_addAF

Pathogenic

0.29

BayesDel_noAF

Pathogenic

0.36

CADD

Benign

DANN

Benign

0.95

DEOGEN2

Uncertain

0.66

.;D;.;T;.

Eigen

Uncertain

0.56

Eigen_PC

Uncertain

0.41

FATHMM_MKL

Pathogenic

0.97

LIST_S2

Uncertain

0.94

D;D;D;D;.

M_CAP

Pathogenic

0.34

MetaRNN

Pathogenic

0.97

D;D;D;D;D

MetaSVM

Pathogenic

0.79

MutationAssessor

Pathogenic

3.8

.;H;.;.;.

PrimateAI

Benign

0.41

PROVEAN

Uncertain

-3.7

D;D;D;.;D

REVEL

Pathogenic

0.73

Sift

Uncertain

0.0020

D;D;D;.;D

Sift4G

Pathogenic

0.0

D;D;D;D;D

Polyphen

1.0

D;D;.;.;D

Vest4

0.94

MutPred

0.80

.;Loss of MoRF binding (P = 0.0844);.;.;.;

MVP

0.94

MPC

0.74

ClinPred

0.87

GERP RS

5.7

Varity_R

0.93

gMVP

0.93

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.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over