rs139622600

Positions:

• chr2-237360162-G-A

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_004369.4(COL6A3):​c.6211-3C>T variant causes a splice region, splice polypyrimidine tract, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00069 in 1,614,096 control chromosomes in the GnomAD database, including 6 homozygotes. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.0035 (2 hom., cov: 32)
  • Exomes 𝑓: 0.00040 (4 hom.)
• Consequence: COL6A3 NM_004369.4 splice_region, splice_polypyrimidine_tract, intron
• Scores: Splicing: ADA: 0.0001765
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:6
• Conservation: PhyloP100: 1.93

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 -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.82).
• BP6: Variant 2-237360162-G-A is Benign according to our data. Variant chr2-237360162-G-A is described in ClinVar as [Benign]. Clinvar id is 94957.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.00349 (532/152304) while in subpopulation AFR AF= 0.012 (500/41556). AF 95% confidence interval is 0.0112. There are 2 homozygotes in gnomad4. There are 258 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd4 at 2 SD gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL6A3	NM_004369.4	c.6211-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		ENST00000295550.9
COL6A3	NM_057166.5	c.4390-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant
COL6A3	NM_057167.4	c.5593-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL6A3	ENST00000295550.9	c.6211-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1	NM_004369.4	P1
COL6A3	ENST00000472056.5	c.4390-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		1
COL6A3	ENST00000353578.9	c.5593-3C>T		splice_region_variant, splice_polypyrimidine_tract_variant, intron_variant		5

Frequencies

GnomAD3 genomes AF: 0.00350 AC: 533 AN: 152186 Hom.: 2 Cov.: 32

Gnomad AFR AF: 0.0121

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00164

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000414

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000441

Gnomad OTH AF: 0.00143

GnomAD3 exomes AF: 0.000983 AC: 247 AN: 251160 Hom.: 4 AF XY: 0.000656 AC XY: 89 AN XY: 135756

Gnomad AFR exome AF: 0.0133

Gnomad AMR exome AF: 0.000752

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: 0.0000264

Gnomad OTH exome AF: 0.000326

GnomAD4 exome AF: 0.000397 AC: 581 AN: 1461792 Hom.: 4 Cov.: 32 AF XY: 0.000320 AC XY: 233 AN XY: 727180

Gnomad4 AFR exome AF: 0.0133

Gnomad4 AMR exome AF: 0.000939

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.0000116

Gnomad4 FIN exome AF: 0.0000187

Gnomad4 NFE exome AF: 0.0000297

Gnomad4 OTH exome AF: 0.000911

GnomAD4 genome AF: 0.00349 AC: 532 AN: 152304 Hom.: 2 Cov.: 32 AF XY: 0.00346 AC XY: 258 AN XY: 74480

Gnomad4 AFR AF: 0.0120

Gnomad4 AMR AF: 0.00163

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000207

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000441

Gnomad4 OTH AF: 0.00142

Alfa AF: 0.00194 Hom.: 1

Bravo AF: 0.00397

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Benign

Submissions summary: Benign:6

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not specified Benign:2

Benign, criteria provided, single submitter	clinical testing	GeneDx	Mar 01, 2018	This variant is considered likely benign or benign based on one or more of the following criteria: it is a conservative change, it occurs at a poorly conserved position in the protein, it is predicted to be benign by multiple in silico algorithms, and/or has population frequency not consistent with disease. -
Benign, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Nov 05, 2012	- -

Collagen 6-related myopathy Benign:1

Benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

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

Benign, criteria provided, single submitter

clinical testing

Invitae

Jan 22, 2024

- -

COL6A3-related disorder Benign:1

Benign, criteria provided, single submitter

clinical testing

PreventionGenetics, part of Exact Sciences

Sep 08, 2021

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

not provided Benign:1

Benign, criteria provided, single submitter

clinical testing

CeGaT Center for Human Genetics Tuebingen

Dec 01, 2023

COL6A3: BP4, BS1, BS2 -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	6.0
DANN	Benign	0.82

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.00018
dbscSNV1_RF	Benign	0.014
SpliceAI score (max)		0.020		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: rs139622600; hg19: chr2-238268805;