21-46124920-G-T

Variant names:

• chr21-46124920-G-T
• rs150999832
• NM_001849.4:c.1770G>T

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001849.4(COL6A2):​c.1770G>T​(p.Thr590Thr) variant causes a splice region, synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000657 in 152,210 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. T590T) has been classified as Uncertain significance.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
• Consequence: COL6A2 NM_001849.4 splice_region, synonymous
• Scores: Splicing: ADA: 0.9880
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.207
• 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, SD, 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: AR, AD Classification: STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• 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: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001849.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL6A2	NM_001849.4	MANE Select	c.1770G>T	p.Thr590Thr	splice_region synonymous	Exon 23 of 28	NP_001840.3
	COL6A2	NM_058174.3	MANE Plus Clinical	c.1770G>T	p.Thr590Thr	splice_region synonymous	Exon 23 of 28	NP_478054.2	P12110-2
	COL6A2	NM_058175.3		c.1770G>T	p.Thr590Thr	splice_region synonymous	Exon 23 of 28	NP_478055.2	P12110-3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL6A2	ENST00000300527.9	TSL:1 MANE Select	c.1770G>T	p.Thr590Thr	splice_region synonymous	Exon 23 of 28	ENSP00000300527.4	P12110-1
	COL6A2	ENST00000397763.6	TSL:5 MANE Plus Clinical	c.1770G>T	p.Thr590Thr	splice_region synonymous	Exon 23 of 28	ENSP00000380870.1	P12110-2
	COL6A2	ENST00000857098.1		c.1965G>T	p.Thr655Thr	splice_region synonymous	Exon 23 of 28	ENSP00000527157.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152210 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome Cov.: 34

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152210 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 74358

African (AFR) AF: 0.0000241 AC: 1 AN: 41454

American (AMR) AF: 0.00 AC: 0 AN: 15288

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4832

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10624

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Bethlem myopathy 1A (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.52
CADD	Benign	18
DANN	Benign	0.56
PhyloP100		0.21

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.99
dbscSNV1_RF	Pathogenic	0.82
SpliceAI score (max)		0.82		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.82		Position offset: 0

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs150999832; hg19: chr21-47544834;