2-237369154-T-C

Position:

• chr2-237369154-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004369.4(COL6A3):​c.4309A>G​(p.Ile1437Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000558 in 1,612,530 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/21 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. I1437F) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: COL6A3 NM_004369.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.59

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 Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.23710054).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL6A3	NM_004369.4	c.4309A>G	p.Ile1437Val	missense_variant	10/44	ENST00000295550.9
COL6A3	NM_057167.4	c.3691A>G	p.Ile1231Val	missense_variant	9/43
COL6A3	NM_057166.5	c.2488A>G	p.Ile830Val	missense_variant	7/41

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL6A3	ENST00000295550.9	c.4309A>G	p.Ile1437Val	missense_variant	10/44	1	NM_004369.4	P1
COL6A3	ENST00000472056.5	c.2488A>G	p.Ile830Val	missense_variant	7/41	1
COL6A3	ENST00000353578.9	c.3691A>G	p.Ile1231Val	missense_variant	9/43	5
COL6A3	ENST00000684597.1	c.117-478A>G		intron_variant

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152204 Hom.: 0 Cov.: 33

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.00000808 AC: 2 AN: 247572 Hom.: 0 AF XY: 0.0000149 AC XY: 2 AN XY: 134228

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: 0.0000180

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000548 AC: 8 AN: 1460208 Hom.: 0 Cov.: 34 AF XY: 0.00000551 AC XY: 4 AN XY: 726510

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: 0.00000719

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152322 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74480

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: 0.0000147

Gnomad4 OTH AF: 0.00

Bravo AF: 0.00000378

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.024	T
BayesDel_noAF	Benign	-0.26
CADD	Benign	18
DANN	Uncertain	0.99
DEOGEN2	Benign	0.17	.;T;.;T;.
Eigen	Benign	-0.27
Eigen_PC	Benign	-0.19
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Benign	0.84	T;T;T;T;.
M_CAP	Uncertain	0.15	D
MetaRNN	Benign	0.24	T;T;T;T;T
MetaSVM	Benign	-0.37	T
MutationAssessor	Benign	0.95	.;L;.;.;.
MutationTaster	Benign	0.95	D;D;D;D;D;D
PrimateAI	Benign	0.42	T
PROVEAN	Benign	-0.41	N;N;N;.;N
REVEL	Benign	0.28
Sift	Benign	0.12	T;T;T;.;T
Sift4G	Benign	0.22	T;T;T;T;T
Polyphen		0.65	P;B;.;.;P
Vest4		0.29
MutPred		0.50		.;Gain of glycosylation at S1432 (P = 0.118);.;.;.;
MVP		0.82
MPC		0.29
ClinPred		0.29	T
GERP RS		4.1
Varity_R		0.092
gMVP		0.33

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: rs144314743; hg19: chr2-238277797;