2-189179604-T-C

Position:

chr2-189179604-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 8P and 4B. PVS1BS2

The NM_000393.5(COL5A2):c.1A>G(p.Met1?) variant causes a start lost change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000035 in 1,602,126 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000036 ( 0 hom. )

Consequence

COL5A2
NM_000393.5 start_lost

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts P:1U:4

Conservation

PhyloP100: 0.455

Variant links:

Genes affected

COL5A2 (HGNC:2210): (collagen type V alpha 2 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. Mutations in this gene are associated with Ehlers-Danlos syndrome, types I and II. [provided by RefSeq, Jul 2008]

COL5A2 links:

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ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 4 ACMG points.

PVS1

Start lost variant, no new inframe start found.

BS2

High AC in GnomAdExome4 at 52 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein
COL5A2	NM_000393.5 linkuse as main transcript	c.1A>G	p.Met1?	start_lost	1/54	ENST00000374866.9	NP_000384.2
COL5A2	XM_011510573.4 linkuse as main transcript	c.-42+45544A>G		intron_variant			XP_011508875.1
COL5A2	XM_047443251.1 linkuse as main transcript	c.-42+45544A>G		intron_variant			XP_047299207.1
COL5A2	XM_047443252.1 linkuse as main transcript	c.-42+45544A>G		intron_variant			XP_047299208.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris
COL5A2	ENST00000374866.9 linkuse as main transcript	c.1A>G	p.Met1?	start_lost	1/54	1	NM_000393.5	ENSP00000364000	P1
COL5A2	ENST00000618828.1 linkuse as main transcript	c.-630A>G		5_prime_UTR_variant	1/47	5		ENSP00000482184
COL5A2	ENST00000649966.1 linkuse as main transcript	c.-42+45544A>G		intron_variant				ENSP00000496785

Frequencies

GnomAD3 genomes

AF:

0.0000263

AC:

AN:

152196

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000345

AC:

AN:

232158

Hom.:

AF XY:

0.0000400

AC XY:

AN XY:

124936

show subpopulations

Gnomad AFR exome

AF:

0.0000685

Gnomad AMR exome

AF:

0.0000900

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:

0.0000295

Gnomad OTH exome

AF:

0.000173

GnomAD4 exome

AF:

0.0000359

AC:

AN:

1449812

Hom.:

Cov.:

AF XY:

0.0000319

AC XY:

AN XY:

720054

show subpopulations

Gnomad4 AFR exome

AF:

0.000150

Gnomad4 AMR exome

AF:

0.0000684

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:

0.0000362

Gnomad4 OTH exome

AF:

0.0000334

GnomAD4 genome

AF:

0.0000263

AC:

AN:

152314

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74474

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.0000654

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000387

Hom.:

Bravo

AF:

0.0000340

ExAC

AF:

0.0000495

AC:

Asia WGS

AF:

0.000289

AC:

AN:

3478

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1Uncertain:4

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Connective tissue disorder

Pathogenic:1

Likely pathogenic, flagged submission

clinical testing

Center for Human Genetics, Inc, Center for Human Genetics, Inc

Nov 01, 2016

- -

Familial thoracic aortic aneurysm and aortic dissection

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Sep 19, 2023

The p.M1? variant (also known as c.1A>G), located in coding exon 1 of the COL5A2 gene, results from an A to G substitution at nucleotide position 1. This alters the methionine residue at the initiation codon. This variant has been detected in a Chiari malformation cohort, and in an individual with an unclassified form of syndromic hypermobility; however, details were limited (Urbizu A et al. PLoS One. 2021 May;16(5):e0251289; Leone MP et al. Hum Genet. 2023 Jun;142(6):785-808). Variations that modify the initiation codon (ATG) are expected to result in either loss of translation initiation, N-terminal truncation, or cause a shift in the mRNA reading frame; however there is an alternate in-frame methionine 1 amino acid downstream from the initiation site. Since supporting evidence is limited at this time, the clinical significance of this variant remains unclear. -

Ehlers-Danlos syndrome, classic type, 2

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Institute of Human Genetics, University of Leipzig Medical Center

Jan 01, 2019

- -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

GeneDx

Aug 26, 2021

Has not been previously published as pathogenic or benign to our knowledge; An in-frame Methionine (p.M2) that could serve as a potential alternative initiation codon; Initiation codon variant in a gene for which most reported pathogenic variants are missense or splice site variants predicted to lead to production of an abnormal protein (Stenson et al., 2014); Reported in ClinVar (ClinVar Variant ID# 391833; Landrum et al., 2016) -

Ehlers-Danlos syndrome, classic type, 1

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jan 18, 2024

This sequence change affects the initiator methionine of the COL5A2 mRNA. The next in-frame methionine is located at codon 2. This variant is present in population databases (rs563606558, gnomAD 0.009%). This variant has not been reported in the literature in individuals affected with COL5A2-related conditions. ClinVar contains an entry for this variant (Variation ID: 391833). Experimental studies and prediction algorithms are not available or were not evaluated, and the functional significance of this variant is currently unknown. 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.25

BayesDel_noAF

Pathogenic

0.32

CADD

Benign

DANN

Benign

0.85

DEOGEN2

Benign

0.15

T;T

Eigen

Benign

-0.31

Eigen_PC

Benign

-0.19

FATHMM_MKL

Benign

0.55

LIST_S2

Uncertain

0.90

.;D

M_CAP

Benign

0.070

MetaRNN

Benign

0.27

T;T

MetaSVM

Benign

-0.64

MutationTaster

Benign

1.0

PROVEAN

Benign

-0.090

N;.

REVEL

Uncertain

0.46

Sift

Pathogenic

0.0

D;.

Sift4G

Pathogenic

0.0

D;.

Polyphen

0.0

B;B

Vest4

0.53

MVP

0.98

ClinPred

0.49

GERP RS

2.5

Varity_R

0.72

gMVP

0.79

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over