rs764556767

Positions:

• chr21-45998425-G-C
• chr21-45998425-G-A

Variant summary

Our verdict is Pathogenic. Variant got 10 ACMG points: 10P and 0B. PS1 PM2 PP3_Strong

The NM_001848.3(COL6A1):​c.1603G>C​(p.Gly535Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,460,944 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 nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin Lovd.

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: COL6A1 NM_001848.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.31

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]

ACMG classification

Verdict is Pathogenic. Variant got 10 ACMG points.

• PS1: Transcript NM_001848.3 (COL6A1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in Lovd
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.97

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL6A1	NM_001848.3	c.1603G>C	p.Gly535Arg	missense_variant	24/35	ENST00000361866.8	NP_001839.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL6A1	ENST00000361866.8	c.1603G>C	p.Gly535Arg	missense_variant	24/35	1	NM_001848.3	ENSP00000355180	P1
COL6A1	ENST00000683550.1	n.378G>C		non_coding_transcript_exon_variant	5/5

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD3 exomes AF: 0.00000399 AC: 1 AN: 250686 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135754

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.0000995

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 AF: 6.84e-7 AC: 1 AN: 1460944 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 726790

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

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

Alfa AF: 0.0000434 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.97
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.97	D;T
Eigen	Uncertain	0.65
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Pathogenic	0.98	D;D
M_CAP	Pathogenic	0.87	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	0.98	D
MutationAssessor	Pathogenic	3.9	H;.
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-5.5	D;.
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0010	D;.
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.82
MutPred		0.82		Gain of methylation at G535 (P = 0.0285);Gain of methylation at G535 (P = 0.0285);
MVP		0.99
MPC		0.90
ClinPred		1.0	D
GERP RS		4.0
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.96
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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: rs764556767; hg19: chr21-47418339;