chr21-46125573-T-G

Variant names:

• chr21-46125573-T-G
• rs760227367
• NM_001849.4:c.1925T>G

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_001849.4(COL6A2):​c.1925T>G​(p.Val642Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,188 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic 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. V642A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COL6A2 NM_001849.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 7.67
• Publications: 0 publications found

Genes affected

COL6A2 (HGNC:2212): (collagen type VI alpha 2 chain) This gene encodes one of the three alpha chains of type VI collagen, a beaded filament collagen found in most connective tissues. The product of this gene contains several domains similar to von Willebrand Factor type A domains. 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 this gene are associated with Bethlem myopathy and Ullrich scleroatonic muscular dystrophy. Three transcript variants have been identified for this gene. [provided by RefSeq, Jul 2008]

COL6A2 Gene-Disease associations (from GenCC):

• collagen 6-related myopathy

  Inheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
• Ullrich congenital muscular dystrophy 1B

  Inheritance: AR, AD Classification: DEFINITIVE Submitted by: G2P
• Bethlem myopathy 1A

  Inheritance: AD, AR Classification: STRONG Submitted by: Genomics England PanelApp
• Ullrich congenital muscular dystrophy 1A

  Inheritance: AD, AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• Bethlem myopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Ullrich congenital muscular dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• myosclerosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.946

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL6A2	NM_001849.4	c.1925T>G	p.Val642Gly	missense_variant	Exon 25 of 28	ENST00000300527.9	NP_001840.3
COL6A2	NM_058174.3	c.1925T>G	p.Val642Gly	missense_variant	Exon 25 of 28		NP_478054.2
COL6A2	NM_058175.3	c.1925T>G	p.Val642Gly	missense_variant	Exon 25 of 28		NP_478055.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL6A2	ENST00000300527.9	c.1925T>G	p.Val642Gly	missense_variant	Exon 25 of 28	1	NM_001849.4	ENSP00000300527.4
COL6A2	ENST00000397763.6	c.1925T>G	p.Val642Gly	missense_variant	Exon 25 of 28	5		ENSP00000380870.1
COL6A2	ENST00000409416.6	c.1925T>G	p.Val642Gly	missense_variant	Exon 24 of 27	5		ENSP00000387115.1
COL6A2	ENST00000413758.1	c.596T>G	p.Val199Gly	missense_variant	Exon 10 of 11	3		ENSP00000395751.1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460188 Hom.: 0 Cov.: 52 AF XY: 0.00 AC XY: 0 AN XY: 726400

African (AFR) AF: 0.00 AC: 0 AN: 33474

American (AMR) AF: 0.00 AC: 0 AN: 44700

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26120

East Asian (EAS) AF: 0.00 AC: 0 AN: 39658

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52128

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5764

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111754

Other (OTH) AF: 0.00 AC: 0 AN: 60334

GnomAD4 genome Cov.: 33

Alfa AF: 0.0000386 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.46	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.74	D;.;.;.;T
Eigen	Pathogenic	0.70
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Uncertain	0.92	D;D;.;D;D
M_CAP	Pathogenic	0.90	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D
MetaSVM	Uncertain	0.74	D
MutationAssessor	Pathogenic	3.1	M;M;M;M;.
PhyloP100		7.7
PrimateAI	Uncertain	0.75	T
PROVEAN	Pathogenic	-5.9	D;D;D;D;D
REVEL	Pathogenic	0.96
Sift	Uncertain	0.0010	D;D;D;D;D
Sift4G	Pathogenic	0.0010	D;D;D;D;D
Polyphen		1.0	D;D;D;D;.
Vest4		0.75
MutPred		0.77		Loss of stability (P = 0.0073);Loss of stability (P = 0.0073);Loss of stability (P = 0.0073);Loss of stability (P = 0.0073);.;
MVP		0.98
MPC		0.69
ClinPred		1.0	D
GERP RS		4.1
Varity_R		0.93
gMVP		0.94
Mutation Taster		=31/69	disease causing

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

Other links and lift over

dbSNP: rs760227367; hg19: chr21-47545487;