chr21-46116387-G-A

Position:

• chr21-46116387-G-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_001849.4(COL6A2):​c.911G>A​(p.Gly304Asp) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. 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. G304V) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL6A2 NM_001849.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.08

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 3 uncertain in NM_001849.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr21-46116387-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 162541.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.988

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL6A2	NM_001849.4	c.911G>A	p.Gly304Asp	missense_variant	8/28	ENST00000300527.9
COL6A2	NM_058174.3	c.911G>A	p.Gly304Asp	missense_variant	8/28	ENST00000397763.6
COL6A2	NM_058175.3	c.911G>A	p.Gly304Asp	missense_variant	8/28

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL6A2	ENST00000300527.9	c.911G>A	p.Gly304Asp	missense_variant	8/28	1	NM_001849.4	P1
COL6A2	ENST00000397763.6	c.911G>A	p.Gly304Asp	missense_variant	8/28	5	NM_058174.3
COL6A2	ENST00000409416.6	c.911G>A	p.Gly304Asp	missense_variant	7/27	5
COL6A2	ENST00000485591.1	n.567G>A		non_coding_transcript_exon_variant	4/7	3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.36	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	30
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D;.;.;.
Eigen	Uncertain	0.63
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D;D;.;D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.7	H;H;H;H
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Pathogenic	0.84	D
PROVEAN	Pathogenic	-5.8	D;D;D;D
REVEL	Pathogenic	0.90
Sift	Pathogenic	0.0	D;D;D;D
Sift4G	Pathogenic	0.0	D;D;D;D
Polyphen		1.0	D;D;D;D
Vest4		0.83
MutPred		0.87		Gain of solvent accessibility (P = 0.1014);Gain of solvent accessibility (P = 0.1014);Gain of solvent accessibility (P = 0.1014);Gain of solvent accessibility (P = 0.1014);
MVP		0.98
MPC		0.70
ClinPred		1.0	D
GERP RS		4.5
Varity_R		0.96
gMVP		1.0

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: rs727502832; hg19: chr21-47536301;