21-45989629-C-T

Variant names:

• chr21-45989629-C-T
• rs141572895
• NM_001848.3:c.880C>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM1 PM2 PP3_Moderate

The NM_001848.3(COL6A1):​c.880C>T​(p.Pro294Ser) variant causes a missense change. The variant allele was found at a frequency of 0.00000274 in 1,460,788 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P294A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: COL6A1 NM_001848.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 7.09
• Publications: 1 publications found

Genes affected

COL6A1 (HGNC:2211): (collagen type VI alpha 1 chain) The collagens are a superfamily of proteins that play a role in maintaining the integrity of various tissues. Collagens are extracellular matrix proteins and have a triple-helical domain as their common structural element. Collagen VI is a major structural component of microfibrils. The basic structural unit of collagen VI is a heterotrimer of the alpha1(VI), alpha2(VI), and alpha3(VI) chains. The alpha2(VI) and alpha3(VI) chains are encoded by the COL6A2 and COL6A3 genes, respectively. The protein encoded by this gene is the alpha 1 subunit of type VI collagen (alpha1(VI) chain). Mutations in the genes that code for the collagen VI subunits result in the autosomal dominant disorder, Bethlem myopathy. [provided by RefSeq, Jul 2008]

COL6A1 Gene-Disease associations (from GenCC):

• collagen 6-related myopathy

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

  Inheritance: AR, AD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, G2P
• Ullrich congenital muscular dystrophy 1A

  Inheritance: AD, AR 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

ACMG classification

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

• PM1: In a hotspot region, there are 21 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_001848.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.895

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001848.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL6A1	NM_001848.3	MANE Select	c.880C>T	p.Pro294Ser	missense	Exon 10 of 35	NP_001839.2

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL6A1	ENST00000361866.8	TSL:1 MANE Select	c.880C>T	p.Pro294Ser	missense	Exon 10 of 35	ENSP00000355180.3

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1460788 Hom.: 0 Cov.: 45 AF XY: 0.00000275 AC XY: 2 AN XY: 726684

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52360

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1111978

Other (OTH) AF: 0.00 AC: 0 AN: 60384

GnomAD4 genome Cov.: 34

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	Bethlem myopathy 1A (1)
-	1	-	COL6A1-related disorder (1)
-	1	-	Inborn genetic diseases (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.70
BayesDel_addAF	Pathogenic	0.27	D
BayesDel_noAF	Pathogenic	0.15
CADD	Uncertain	26
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.90	D
Eigen	Uncertain	0.62
Eigen_PC	Uncertain	0.56
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.90	D
M_CAP	Pathogenic	0.70	D
MetaRNN	Pathogenic	0.89	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.3	M
PhyloP100		7.1
PrimateAI	Uncertain	0.77	T
PROVEAN	Pathogenic	-6.7	D
REVEL	Pathogenic	0.70
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.013	D
Polyphen		1.0	D
Vest4		0.73
MutPred		0.43		Gain of phosphorylation at P294 (P = 0.0124)
MVP		0.80
MPC		0.22
ClinPred		0.98	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.79
gMVP		0.77
Mutation Taster		=22/78	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: rs141572895; hg19: chr21-47409543;