rs587779489

Positions:

• chr2-188994577-G-A
• chr2-188994577-G-C

Variant summary

Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000090.4(COL3A1):​c.1330G>A​(p.Gly444Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 12/21 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL3A1 NM_000090.4 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.01

Genes affected

COL3A1 (HGNC:2201): (collagen type III alpha 1 chain) This gene encodes the pro-alpha1 chains of type III collagen, a fibrillar collagen that is found in extensible connective tissues such as skin, lung, uterus, intestine and the vascular system, frequently in association with type I collagen. Mutations in this gene are associated with Ehlers-Danlos syndrome type IV, and with aortic and arterial aneurysms. [provided by R. Dalgleish, Feb 2008]

ACMG classification

Verdict is Pathogenic. Variant got 15 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL3A1. . Gene score misZ: 4.0879 (greater than the threshold 3.09). Trascript score misZ: 4.5995 (greater than threshold 3.09). The gene has 495 curated pathogenic missense variants (we use a threshold of 10). The gene has 19 curated benign missense variants. GenCC has associacion of the gene with Ehlers-Danlos syndrome, vascular type, autosomal dominant Ehlers-Danlos syndrome, vascular type, polymicrogyria with or without vascular-type Ehlers-Danlos syndrome.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.995
• PP5: Variant 2-188994577-G-A is Pathogenic according to our data. Variant chr2-188994577-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 101185.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-188994577-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL3A1	NM_000090.4	c.1330G>A	p.Gly444Arg	missense_variant	19/51	ENST00000304636.9	NP_000081.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL3A1	ENST00000304636.9	c.1330G>A	p.Gly444Arg	missense_variant	19/51	1	NM_000090.4	ENSP00000304408.4
COL3A1	ENST00000450867.2	c.1231G>A	p.Gly411Arg	missense_variant	18/50	1		ENSP00000415346.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Ehlers-Danlos syndrome, type 4 Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Institute for Medical Genetics and Human Genetics, Charité - Universitätsmedizin Berlin	Sep 22, 2022	- -
Pathogenic, no assertion criteria provided	clinical testing	Collagen Diagnostic Laboratory, University of Washington	-	- -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 16, 2024	This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 444 of the COL3A1 protein (p.Gly444Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with vascular Ehlers-Danlos syndrome (PMID: 10706896, 20518783, 22492385). This variant is also known as G277R. ClinVar contains an entry for this variant (Variation ID: 101185). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt COL3A1 protein function with a positive predictive value of 95%. This variant disrupts the triple helix domain of COL3A1. Glycine residues within the Gly-Xaa-Yaa repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). In COL3A1, variants that affect these glycine residues are significantly enriched in individuals with disease (PMID: 24922459, 25758994) compared to the general population (ExAC). For these reasons, this variant has been classified as Pathogenic. -

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

GeneDx

Dec 19, 2022

Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Occurs in the triple helical domain and replaces the glycine in the canonical Gly-X-Y repeat; missense substitution of a canonical glycine residue is expected to disrupt normal protein folding and function, and this is an established mechanism of disease (HGMD); Also known as p.(G277R); Reported in ClinVar as pathogenic (ClinVar Variant ID# 101185; ClinVar); This variant is associated with the following publications: (PMID: 22492385, 24922459, 10706896, 31353273, 30474650, 30919682, 33851936, 20518783) -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
CADD	Pathogenic	32
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.90	D;.
Eigen	Pathogenic	1.2
Eigen_PC	Pathogenic	1.1
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.97	D
MetaRNN	Pathogenic	1.0	D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	3.8	H;H
PrimateAI	Pathogenic	0.88	D
PROVEAN	Pathogenic	-6.8	D;D
REVEL	Pathogenic	0.98
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.98
MutPred		0.98		Gain of MoRF binding (P = 0.0211);Gain of MoRF binding (P = 0.0211);
MVP		1.0
MPC		0.75
ClinPred		1.0	D
GERP RS		6.2
Varity_R		0.91
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: rs587779489; hg19: chr2-189859303; COSMIC: COSV58583545; COSMIC: COSV58583545;