9-134842281-G-A

Position:

• chr9-134842281-G-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP2 PP3_Strong

The NM_000093.5(COL5A1):​c.5495G>A​(p.Gly1832Glu) 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G1832A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL5A1 NM_000093.5 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 9.73

Genes affected

COL5A1 (HGNC:2209): (collagen type V alpha 1 chain) This gene encodes an alpha chain for one of the low abundance fibrillar collagens. Fibrillar collagen molecules are trimers that can be composed of one or more types of alpha chains. Type V collagen is found in tissues containing type I collagen and appears to regulate the assembly of heterotypic fibers composed of both type I and type V collagen. This gene product is closely related to type XI collagen and it is possible that the collagen chains of types V and XI constitute a single collagen type with tissue-specific chain combinations. The encoded procollagen protein occurs commonly as the heterotrimer pro-alpha1(V)-pro-alpha1(V)-pro-alpha2(V). Mutations in this gene are associated with Ehlers-Danlos syndrome, types I and II. Alternative splicing of this gene results in multiple transcript variants. [provided by RefSeq, May 2013]

LOC101448202 (HGNC:):

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 benign, 4 uncertain in NM_000093.5
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL5A1. . Gene score misZ 2.0682 (greater than the threshold 3.09). Trascript score misZ 4.1823 (greater than threshold 3.09). GenCC has associacion of gene with Ehlers-Danlos syndrome, classic type, 1, arterial disorder, Ehlers-Danlos syndrome, classic type.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.993

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL5A1	NM_000093.5	c.5495G>A	p.Gly1832Glu	missense_variant	66/66	ENST00000371817.8
LOC101448202	NR_103451.2	n.71-22072C>T		intron_variant, non_coding_transcript_variant
COL5A1	NM_001278074.1	c.5495G>A	p.Gly1832Glu	missense_variant	66/66

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL5A1	ENST00000371817.8	c.5495G>A	p.Gly1832Glu	missense_variant	66/66	1	NM_000093.5	P4
COL5A1	ENST00000371820.4	c.5495G>A	p.Gly1832Glu	missense_variant	66/66	2		A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Familial thoracic aortic aneurysm and aortic dissection Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Feb 06, 2018

The p.G1832E variant (also known as c.5495G>A), located in coding exon 66 of the COL5A1 gene, results from a G to A substitution at nucleotide position 5495. The glycine at codon 1832 is replaced by glutamic acid, an amino acid with some similar properties. Another alteration affecting the same amino acid, p.G1823R (c.5494G>A), has been reported in association with Ehlers Danlos syndrome (Symoens S et al. Hum. Mutat., 2012 Oct;33:1485-93). This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

Ehlers-Danlos syndrome, classic type, 1 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 23, 2017

This sequence change replaces glycine with glutamic acid at codon 1832 of the COL5A1 protein (p.Gly1832Glu). The glycine residue is highly conserved and there is a moderate physicochemical difference between glycine and glutamic acid. 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. Algorithms developed to predict the effect of missense changes on protein structure and function do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with COL5A1-related disease. This variant is not present in population databases (ExAC no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	27
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.67	D;.
Eigen	Pathogenic	0.97
Eigen_PC	Pathogenic	0.87
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.74	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.1	H;H
MutationTaster	Benign	1.0	D
PrimateAI	Pathogenic	0.80	T
PROVEAN	Pathogenic	-6.6	D;.
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D;.
Sift4G	Pathogenic	0.0010	D;D
Polyphen		1.0	D;.
Vest4		0.98
MutPred		0.95		Loss of catalytic residue at C1835 (P = 0.0936);Loss of catalytic residue at C1835 (P = 0.0936);
MVP		0.97
MPC		0.38
ClinPred		1.0	D
GERP RS		4.7
Varity_R		0.95
gMVP		0.91

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: rs1554727410; hg19: chr9-137734127;