NM_004369.4:c.3270C>T

Variant names:

• chr2-237374821-G-A
• rs113781746
• NM_004369.4:c.3270C>T

Variant summary

Our verdict is Benign. Variant got -21 ACMG points: 0P and 21B. BP4_Strong BP6_Very_Strong BP7 BS1 BS2

The NM_004369.4(COL6A3):​c.3270C>T​(p.Asp1090Asp) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00208 in 1,613,998 control chromosomes in the GnomAD database, including 10 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0017 (0 hom., cov: 32)
  • Exomes 𝑓: 0.0021 (10 hom.)
• Consequence: COL6A3 NM_004369.4 synonymous
• Clinical Significance: Benign/Likely benign criteria provided, multiple submitters, no conflicts B:8
• Conservation: PhyloP100: -1.20

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]

ACMG classification

Verdict is Benign. Variant got -21 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant 2-237374821-G-A is Benign according to our data. Variant chr2-237374821-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 166946.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-237374821-G-A is described in Lovd as [Likely_benign].
• BP7: Synonymous conserved (PhyloP=-1.2 with no splicing effect.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00174 (265/152132) while in subpopulation NFE AF= 0.00215 (146/67998). AF 95% confidence interval is 0.00186. There are 0 homozygotes in gnomad4. There are 137 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High Homozygotes in GnomAdExome4 at 10 SD gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL6A3	NM_004369.4	c.3270C>T	p.Asp1090Asp	synonymous_variant	Exon 8 of 44	ENST00000295550.9	NP_004360.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL6A3	ENST00000295550.9	c.3270C>T	p.Asp1090Asp	synonymous_variant	Exon 8 of 44	1	NM_004369.4	ENSP00000295550.4

Frequencies

GnomAD3 genomes AF: 0.00174 AC: 265 AN: 152014 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.000362

Gnomad AMI AF: 0.0297

Gnomad AMR AF: 0.00157

Gnomad ASJ AF: 0.000288

Gnomad EAS AF: 0.000388

Gnomad SAS AF: 0.000623

Gnomad FIN AF: 0.00445

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00215

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00166 AC: 416 AN: 251282 Hom.: 2 AF XY: 0.00149 AC XY: 202 AN XY: 135876

Gnomad AFR exome AF: 0.000123

Gnomad AMR exome AF: 0.00159

Gnomad ASJ exome AF: 0.0000992

Gnomad EAS exome AF: 0.000326

Gnomad SAS exome AF: 0.000555

Gnomad FIN exome AF: 0.00361

Gnomad NFE exome AF: 0.00216

Gnomad OTH exome AF: 0.00196

GnomAD4 exome AF: 0.00212 AC: 3095 AN: 1461866 Hom.: 10 Cov.: 32 AF XY: 0.00205 AC XY: 1488 AN XY: 727236

Gnomad4 AFR exome AF: 0.000239

Gnomad4 AMR exome AF: 0.00136

Gnomad4 ASJ exome AF: 0.000115

Gnomad4 EAS exome AF: 0.000126

Gnomad4 SAS exome AF: 0.000487

Gnomad4 FIN exome AF: 0.00405

Gnomad4 NFE exome AF: 0.00238

Gnomad4 OTH exome AF: 0.00177

GnomAD4 genome AF: 0.00174 AC: 265 AN: 152132 Hom.: 0 Cov.: 32 AF XY: 0.00184 AC XY: 137 AN XY: 74352

Gnomad4 AFR AF: 0.000361

Gnomad4 AMR AF: 0.00157

Gnomad4 ASJ AF: 0.000288

Gnomad4 EAS AF: 0.000389

Gnomad4 SAS AF: 0.000623

Gnomad4 FIN AF: 0.00445

Gnomad4 NFE AF: 0.00215

Gnomad4 OTH AF: 0.00

Alfa AF: 0.00178 Hom.: 0

Bravo AF: 0.00139

Asia WGS AF: 0.000289 AC: 1 AN: 3478

EpiCase AF: 0.00164

EpiControl AF: 0.00160

ClinVar

Significance: Benign/Likely benign

Submissions summary: Benign:8

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Benign:4

-

Clinical Genetics, Academic Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Jun 01, 2020

GeneDx

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

Clinical Genetics DNA and cytogenetics Diagnostics Lab, Erasmus MC, Erasmus Medical Center

Significance: Likely benign

Review Status: no assertion criteria provided

Collection Method: clinical testing

- -

Nov 01, 2023

CeGaT Center for Human Genetics Tuebingen

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

COL6A3: BP4, BP7 -

not specified Benign:2

Mar 10, 2014

Eurofins Ntd Llc (ga)

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

-

PreventionGenetics, part of Exact Sciences

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Collagen 6-related myopathy Benign:1

Jan 13, 2018

Illumina Laboratory Services, Illumina

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as benign is not then subjected to further curation. The score for this variant resulted in a classification of benign for this disease. -

Bethlem myopathy 1A Benign:1

Feb 03, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	0.066
DANN	Benign	0.58

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

Other links and lift over

dbSNP: rs113781746; hg19: chr2-238283464; COSMIC: COSV99802134; COSMIC: COSV99802134;