rs1229093142

Positions:

• chr2-188994237-C-T

Variant summary

Our verdict is Uncertain significance. Variant got 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The ENST00000304636.9(COL3A1):​c.1198C>T​(p.Pro400Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,780 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★★). Synonymous variant affecting the same amino acid position (i.e. P400P) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: COL3A1 ENST00000304636.9 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:4
• Conservation: PhyloP100: 2.96

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 Uncertain_significance. Variant got 5 ACMG points.

• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in ENST00000304636.9
• 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). 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.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL3A1	NM_000090.4	c.1198C>T	p.Pro400Ser	missense_variant	18/51	ENST00000304636.9	NP_000081.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL3A1	ENST00000304636.9	c.1198C>T	p.Pro400Ser	missense_variant	18/51	1	NM_000090.4	ENSP00000304408	P1
COL3A1	ENST00000450867.2	c.1099C>T	p.Pro367Ser	missense_variant	17/50	1		ENSP00000415346

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000398 AC: 1 AN: 251182 Hom.: 0 AF XY: 0.00000737 AC XY: 1 AN XY: 135732

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000881

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461780 Hom.: 0 Cov.: 32 AF XY: 0.00000275 AC XY: 2 AN XY: 727196

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Ambry Genetics	Feb 14, 2017	The p.P400S variant (also known as c.1198C>T), located in coding exon 18 of the COL3A1 gene, results from a C to T substitution at nucleotide position 1198. The proline at codon 400 is replaced by serine, an amino acid with similar properties. This amino acid position is not well conserved in available vertebrate species, and serine is the reference amino acid in other vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -
Uncertain significance, criteria provided, single submitter	clinical testing	Color Diagnostics, LLC DBA Color Health	Mar 11, 2020	This missense variant replaces proline with serine at codon 400 of the COL3A1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 1/251182 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Ehlers-Danlos syndrome, type 4 Uncertain:2

Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Aug 13, 2021	This sequence change replaces proline with serine at codon 400 of the COL3A1 protein (p.Pro400Ser). The proline residue is highly conserved and there is a moderate physicochemical difference between proline and serine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with COL3A1-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Not Available"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	All of Us Research Program, National Institutes of Health	May 31, 2023	This missense variant replaces proline with serine at codon 400 of the COL3A1 protein. Computational prediction suggests that this variant may not impact protein structure and function (internally defined REVEL score threshold <= 0.5, PMID: 27666373). Splice site prediction tools suggest that this variant may not impact RNA splicing. To our knowledge, functional studies have not been reported for this variant. This variant has not been reported in individuals affected with cardiovascular disorders in the literature. This variant has been identified in 1/251182 chromosomes in the general population by the Genome Aggregation Database (gnomAD). The available evidence is insufficient to determine the role of this variant in disease conclusively. Therefore, this variant is classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.13
BayesDel_addAF	Uncertain	0.12	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	22
DANN	Benign	0.94
DEOGEN2	Uncertain	0.48	T;.
Eigen	Uncertain	0.22
Eigen_PC	Uncertain	0.25
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.92	D;D
M_CAP	Benign	0.061	D
MetaRNN	Uncertain	0.44	T;T
MetaSVM	Benign	-0.68	T
MutationAssessor	Benign	1.7	L;L
MutationTaster	Benign	1.0	D;D
PrimateAI	Uncertain	0.54	T
PROVEAN	Benign	-0.67	N;N
REVEL	Uncertain	0.36
Sift	Benign	0.53	T;D
Sift4G	Benign	0.54	T;T
Polyphen		0.0010	B;.
Vest4		0.54
MutPred		0.51		Gain of phosphorylation at P400 (P = 0.0115);Gain of phosphorylation at P400 (P = 0.0115);
MVP		0.71
MPC		0.63
ClinPred		0.34	T
GERP RS		4.8
Varity_R		0.078
gMVP		0.59

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: rs1229093142; hg19: chr2-189858963;