2-189008960-G-A

Position:

• chr2-189008960-G-A

Variant summary

Our verdict is Pathogenic. Variant got 13 ACMG points: 13P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The ENST00000304636.9(COL3A1):​c.3562G>A​(p.Gly1188Arg) 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 variant affecting the same amino acid position, but resulting in a different missense (i.e. G1188E) has been classified as Pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL3A1 ENST00000304636.9 missense
• Clinical Significance: Pathogenic criteria provided, single submitter 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 13 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in ENST00000304636.9
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr2-189008961-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 17218.Status of the report is no_assertion_criteria_provided, 0 stars.
• 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). GenCC has associacion of 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, 0.993
• PP5: Variant 2-189008960-G-A is Pathogenic according to our data. Variant chr2-189008960-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 101202.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL3A1	NM_000090.4	c.3562G>A	p.Gly1188Arg	missense_variant	48/51	ENST00000304636.9	NP_000081.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL3A1	ENST00000304636.9	c.3562G>A	p.Gly1188Arg	missense_variant	48/51	1	NM_000090.4	ENSP00000304408	P1
COL3A1	ENST00000450867.2	c.3463G>A	p.Gly1155Arg	missense_variant	47/50	1		ENSP00000415346
COL3A1	ENST00000487010.1	n.659G>A		non_coding_transcript_exon_variant	1/3	2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 24, 2016

The p.G1188R pathogenic mutation (also known as c.3562G>A), located in coding exon 48 of the COL3A1 gene, results from a G to A substitution at nucleotide position 3562. The glycine at codon 1188 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 (Schwarze U et al. Am J Hum Genet. 1997;61(6):1276-1286; Pepin MG et al. Genet Med. 2014;16(12):881-8). The p.G1188R mutation (reported with the legacy nomenclature p.G1021R) has been detected in two unrelated individuals with Ehlers-Danlos syndrome type IV (EDS IV), and cultured skin fibroblasts from both patients have been shown to produce abnormal type III procollagen (Pope FM et al. Br. J. Dermatol. 1996;135:163-81; Pepin M et al. N. Engl. J. Med. 2000;342:673-80). In addition, two other alterations associated with EDS IV, p.G1188V and p.G1188E, have been described in the same codon (Narcisi P et al. Am. J. Med. Genet. 1993;46:278-83; Drera B et al. J. Dermatol. Sci. 2011;64:237-40). Based on the supporting evidence, this alteration is interpreted as a disease-causing mutation. -

Ehlers-Danlos syndrome, type 4 Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Collagen Diagnostic Laboratory, University of Washington

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.56	D
BayesDel_noAF	Pathogenic	0.57
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.96	D;.
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	0.95	D
MutationAssessor	Pathogenic	4.0	H;.
MutationTaster	Benign	1.0	D;D
PrimateAI	Pathogenic	0.93	D
PROVEAN	Pathogenic	-7.4	D;D
REVEL	Pathogenic	1.0
Sift	Uncertain	0.0020	D;D
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.85
MutPred		0.98		Gain of methylation at G1188 (P = 0.0161);.;
MVP		0.99
MPC		0.25
ClinPred		1.0	D
GERP RS		5.5
Varity_R		0.96
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: rs587779504; hg19: chr2-189873686;