21-46132475-G-C

Position:

• chr21-46132475-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The ENST00000300527.9(COL6A2):​c.2983G>C​(p.Ala995Pro) 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. A995T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: COL6A2 ENST00000300527.9 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.43

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 Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.88

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL6A2	NM_001849.4	c.2983G>C	p.Ala995Pro	missense_variant	28/28	ENST00000300527.9	NP_001840.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL6A2	ENST00000300527.9	c.2983G>C	p.Ala995Pro	missense_variant	28/28	1	NM_001849.4	ENSP00000300527	P1

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000417 AC: 1 AN: 240084 Hom.: 0 AF XY: 0.00000763 AC XY: 1 AN XY: 131084

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000291

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: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 6.88e-7 AC: 1 AN: 1454406 Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1 AN XY: 723270

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000224

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 34

ExAC AF: 0.00000826 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.16	D
BayesDel_noAF	Uncertain	0.080
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Benign	0.32	T
Eigen	Uncertain	0.47
Eigen_PC	Uncertain	0.38
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Benign	0.84	T
M_CAP	Pathogenic	0.52	D
MetaRNN	Pathogenic	0.88	D
MetaSVM	Uncertain	0.23	D
MutationAssessor	Uncertain	2.4	M
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	-1.8	N
REVEL	Pathogenic	0.76
Sift	Benign	0.21	T
Sift4G	Benign	0.095	T
Polyphen		1.0	D
Vest4		0.80
MutPred		0.55		Loss of stability (P = 0.0703);
MVP		0.93
MPC		0.69
ClinPred		0.84	D
GERP RS		3.4
Varity_R		0.31
gMVP		0.93

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: rs35139588; hg19: chr21-47552389;