rs778039312

Variant names:

• chr2-237374437-C-T
• rs778039312
• NM_004369.4:c.3654G>A

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_004369.4(COL6A3):​c.3654G>A​(p.Pro1218Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000397 in 1,613,172 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 Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000042 (0 hom.)
• Consequence: COL6A3 NM_004369.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:2
• Conservation: PhyloP100: -4.21

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 Likely_benign. Variant got -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.8).
• BP6: Variant 2-237374437-C-T is Benign according to our data. Variant chr2-237374437-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 476518.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-4.21 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL6A3	NM_004369.4	c.3654G>A	p.Pro1218Pro	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.3654G>A	p.Pro1218Pro	synonymous_variant	Exon 8 of 44	1	NM_004369.4	ENSP00000295550.4

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152206 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

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: 0.0000241 AC: 6 AN: 248906 Hom.: 0 AF XY: 0.0000296 AC XY: 4 AN XY: 135096

Gnomad AFR exome AF: 0.0000637

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000547

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.0000472

Gnomad NFE exome AF: 0.0000178

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000418 AC: 61 AN: 1460966 Hom.: 0 Cov.: 32 AF XY: 0.0000495 AC XY: 36 AN XY: 726830

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000756

Gnomad4 SAS exome AF: 0.0000348

Gnomad4 FIN exome AF: 0.000114

Gnomad4 NFE exome AF: 0.0000423

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152206 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74338

Gnomad4 AFR AF: 0.0000241

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

Alfa AF: 0.0000331 Hom.: 0

Bravo AF: 0.0000151

EpiCase AF: 0.000109

EpiControl AF: 0.000119

ClinVar

Significance: Likely benign

Submissions summary: Benign:2

Revision: criteria provided, single submitter

Submissions by phenotype

Bethlem myopathy 1A Benign:1

Nov 08, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

COL6A3-related disorder Benign:1

Oct 24, 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 v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.80
CADD	Benign	0.36
DANN	Benign	0.50

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: rs778039312; hg19: chr2-238283080;