rs794728044

chr2-188994280-G-Achr2-188994280-G-T

Variant summary

Our verdict is Pathogenic. Variant got 19 ACMG points: 19P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Very_Strong

The NM_000090.4(COL3A1):c.1241G>A(p.Gly414Asp) 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 (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G414C) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL3A1 NM_000090.4 missense
• Clinical Significance: Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• 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 19 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 2 benign, 7 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 chr2-188994279-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2798833.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, 0.995
• PP5: Variant 2-188994280-G-A is Pathogenic according to our data. Variant chr2-188994280-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 263829.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-188994280-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL3A1	NM_000090.4	c.1241G>A	p.Gly414Asp	missense_variant	18/51	ENST00000304636.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL3A1	ENST00000304636.9	c.1241G>A	p.Gly414Asp	missense_variant	18/51	1	NM_000090.4	P1
COL3A1	ENST00000450867.2	c.1142G>A	p.Gly381Asp	missense_variant	17/50	1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 20, 2020

The p.G414D variant (also known as c.1241G>A), located in coding exon 18 of the COL3A1 gene, results from a G to A substitution at nucleotide position 1241. The glycine at codon 414 is replaced by aspartic acid, an amino acid with similar 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). 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). Alternate amino acid substitutions at this codon, p.G414V and p.G414C, have been reported in individuals with vascular Ehlers-Danlos syndrome (Ferre FC et al. BMJ Open. 2012;2(2):e000705; Pepin MG et al. Genet Med. 2014;16(12):881-8). This variant was not reported in population-based cohorts in the Genome Aggregation Database (gnomAD). 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 majority of available evidence to date, this variant is likely to be pathogenic. -

Ehlers-Danlos syndrome, type 4 Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München

May 25, 2023

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.57	D
BayesDel_noAF	Pathogenic	0.58
Cadd	Pathogenic	29
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.91	D;.
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.95	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H;H
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.90	D
PROVEAN	Pathogenic	-6.0	D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	D;.
Vest4		0.98
MutPred		1.0		Loss of methylation at R413 (P = 0.0318);Loss of methylation at R413 (P = 0.0318);
MVP		0.99
MPC		0.82
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.99
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: rs794728044; hg19: chr2-189859006;