rs121912913

chr2-189004302-G-Achr2-189004302-G-T

Variant summary

Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PS1_Moderate PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_000090.4(COL3A1):c.2869G>A(p.Gly957Ser) 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 (★). Another nucleotide change resulting in same amino acid change has been previously reported as Likely pathogenicin UniProt. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G957C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL3A1 NM_000090.4 missense
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 10.0

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.

• PS1: Transcript NM_000090.4 (COL3A1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in UniProt
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 uncertain in NM_000090.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-189004303-G-T is described in ClinVar as [Pathogenic]. Clinvar id is 101446.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP2: Missense variant where missense usually causes diseases, COL3A1
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.996
• PP5: Variant 2-189004302-G-A is Pathogenic according to our data. Variant chr2-189004302-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1458349.Status of the report is criteria_provided_single_submitter, 1 stars. Variant chr2-189004302-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL3A1	NM_000090.4	c.2869G>A	p.Gly957Ser	missense_variant	40/51	ENST00000304636.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL3A1	ENST00000304636.9	c.2869G>A	p.Gly957Ser	missense_variant	40/51	1	NM_000090.4	P1
COL3A1	ENST00000450867.2	c.2770G>A	p.Gly924Ser	missense_variant	39/50	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Ehlers-Danlos syndrome, type 4 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Mar 14, 2022

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the p.Gly957Ser amino acid residue in COL3A1. Other variant(s) that disrupt this residue have been observed in individuals with COL3A1-related conditions (PMID: 24650746; Invitae), which suggests that this may be a clinically significant amino acid residue. 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). 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. This variant is also known as G790S. This missense change has been observed in individual(s) with vascular Ehlers-Danlos syndrome (PMID: 2492273, 30474650, 30919682). This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 957 of the COL3A1 protein (p.Gly957Ser). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.94
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
Cadd	Pathogenic	29
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.89	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Pathogenic	0.93	D
MetaRNN	Pathogenic	1.0	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.9	H
MutationTaster	Benign	1.0	A;A
PrimateAI	Pathogenic	0.85	D
PROVEAN	Pathogenic	-5.0	D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0080	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.99		Gain of glycosylation at G957 (P = 0.012);
MVP		1.0
MPC		1.6
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.96
gMVP		0.99

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs121912913; hg19: chr2-189869028;