chr2-189001554-G-A
Variant summary
Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PM2PP2PP3_StrongPP5_Very_Strong
The NM_000090.4(COL3A1):c.2356G>A(p.Gly786Arg) 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 Likely pathogenic (★★).
Frequency
Consequence
NM_000090.4 missense
Scores
Clinical Significance
Conservation
Genome browser will be placed here
ACMG classification
Verdict is Pathogenic. Variant got 15 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
COL3A1 | ENST00000304636.9 | c.2356G>A | p.Gly786Arg | missense_variant | Exon 34 of 51 | 1 | NM_000090.4 | ENSP00000304408.4 | ||
COL3A1 | ENST00000450867.2 | c.2257G>A | p.Gly753Arg | missense_variant | Exon 33 of 50 | 1 | ENSP00000415346.2 |
Frequencies
GnomAD3 genomes Cov.: 32
GnomAD4 exome Cov.: 34
GnomAD4 genome Cov.: 32
ClinVar
Submissions by phenotype
Ehlers-Danlos syndrome, type 4 Pathogenic:4
This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 786 of the COL3A1 protein (p.Gly786Arg). 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: 2243125, 18043893, 24399159, 24650746, 30474650, 31126764). It has also been observed to segregate with disease in related individuals. This variant is also known as p.Gly619Arg. ClinVar contains an entry for this variant (Variation ID: 17200). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) 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. -
- -
- -
The c.2356G>A (p.Gly786Arg) variant in COL3A1 gene that encodes for collagen type III alpha 1 chain, has been reported in at least eight individuals affected with vascular Ehlers-Danlos syndrome (vEDS) or other COL3A1-related phenotypes (PMID: 18043893, 24399159, 24650746, 30474650, 31126764, 36189931, 36977837, 37655064). This variant affects a conserved glycine residue changes to which are significantly enriched in individuals with COL3A1-related conditions (PMID: 24922459, 25758994). Glycine residues within the Gly-X-Y repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). Computational prediction tools suggest that this variant may have deleterious effect on the protein function (REVEL score: 0.995). This variant is absent in the general population database gnomAD (v4.1.0), and interpreted as likely pathogenic/pathogenic by multiple submitters in ClinVar database (ClinVar ID: 17200). Another variant affecting the same amino acid residue, p.Gly786Val has been reported in two individuals with vEDS (PMID: 30474650) and classified as pathogenic by single submitter in ClinVar (ID: 101274). Therefore, the c.2356G>A (p.Gly786Arg) variant in COL3A1 gene is classified as likely pathogenic. -
Familial thoracic aortic aneurysm and aortic dissection Pathogenic:2
The p.G786R pathogenic mutation (also known as c.2356G>A), located in coding exon 34 of the COL3A1 gene, results from a G to A substitution at nucleotide position 2356. The glycine at codon 786 is replaced by arginine, an amino acid with dissimilar properties. The majority (approximately two-thirds) of COL3A1 mutations identified to date have involved the substitution of another amino acid for glycine within the triple-helical domain (Pepin MG et al. Genet Med. 2014;16(12):881-8; Frank M et al. Eur J Hum Genet. 2015;23(12):1657-64). This particular glycine substitution (also known as legacy p.G619R) has been reported in individuals with vascular Ehlers-Danlos syndrome (vEDS), as well as in affected family members (Kontusaari S et al. J. Clin. Invest., 1990 Nov;86:1465-73; Kuivaniemi H et al. J. Clin. Invest., 1991 Nov;88:1441-4; Pepin MG et al. Genet. Med., 2014 Dec;16:881-8; Morissette R et al. Circ Cardiovasc Genet, 2014 Feb;7:80-8). Internal structural analysis indicates that this alteration disrupts the characteristic G-X-Y motif in the COL3A1 protein and inserts a bulky side chain into a sterically-constrained region (Bella J et al. Science. 1994;266:75-81; Hohenester E et al. Proc. Natl. Acad. Sci. U.S.A. 2008;105:18273-7; Ambry internal data). This variant is considered to be rare based on population cohorts in the Genome Aggregation Database (gnomAD). An alternate amino acid substitution at this codon, p.G786V, has also been detected in vEDS cohorts (Pepin MG et al. Genet. Med., 2014 Dec;16:881-8; Henneton P et al. Circ Genom Precis Med, 2019 Mar;12:e001996). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -
This variant changes one of the conserved glycine residues within the Gly-Xaa-Yaa repeat motifs of the triple helical domain of the COL3A1 protein. Although functional studies have not been reported for this variant, conserved glycine residues within the Gly-Xaa-Yaa repeats are required for the structural stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236) and missense variants occurring at these glycine residues have been associated with disease (PMID: 24922459, 25758994). Computational prediction suggests that this variant may have deleterious impact on protein structure and function. This variant has been reported in multiple unrelated individuals affected with vascular Ehlers Danlos syndrome (PMID: 18043893, 24399159, 24650746, 30474650, 31126764, 36977837, 37068529, 37655064). It has been shown that this variant segregates with disease in multiple affected individuals in one family (PMID: 36977837). This variant has also been reported in multiple individuals in one family affected with aortic aneurysm (PMID: 2243125). This variant has not been identified in the general population by the Genome Aggregation Database (gnomAD). Based on the available evidence, this variant is classified as Pathogenic. -
not provided Pathogenic:2
- -
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.(G619R); This variant is associated with the following publications: (PMID: 18043893, 25525159, 2243125, 30474650, 31126764, 24650746, 24399159, 9036918, 10706896) -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at