2-189110428-G-A

Position:

• chr2-189110428-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_000393.5(COL5A2):​c.119C>T​(p.Ala40Val) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,434 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COL5A2 NM_000393.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.61

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL5A2. . Gene score misZ 2.4395 (greater than the threshold 3.09). Trascript score misZ 3.3523 (greater than threshold 3.09). GenCC has associacion of gene with Ehlers-Danlos syndrome, classic type, 2, Ehlers-Danlos syndrome, classic type.
• BP4: Computational evidence support a benign effect (MetaRNN=0.34467703).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL5A2	NM_000393.5	c.119C>T	p.Ala40Val	missense_variant	2/54	ENST00000374866.9	NP_000384.2
COL5A2	XM_011510573.4	c.-20C>T		5_prime_UTR_variant	5/57		XP_011508875.1
COL5A2	XM_047443251.1	c.-20C>T		5_prime_UTR_variant	7/59		XP_047299207.1
COL5A2	XM_047443252.1	c.-20C>T		5_prime_UTR_variant	6/58		XP_047299208.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL5A2	ENST00000374866.9	c.119C>T	p.Ala40Val	missense_variant	2/54	1	NM_000393.5	ENSP00000364000	P1
COL5A2	ENST00000618828.1	c.-512C>T		5_prime_UTR_variant	2/47	5		ENSP00000482184
COL5A2	ENST00000649966.1	c.-20C>T		5_prime_UTR_variant	2/11			ENSP00000496785

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461434 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727070

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: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

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

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 25, 2017

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 (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with COL5A2-related disease. This variant is not present in population databases (ExAC no frequency). This sequence change replaces alanine with valine at codon 40 of the COL5A2 protein (p.Ala40Val). The alanine residue is highly conserved and there is a small physicochemical difference between alanine and valine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.15
BayesDel_addAF	Benign	-0.017	T
BayesDel_noAF	Benign	-0.26
CADD	Uncertain	26
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.19	T;T
Eigen	Benign	0.073
Eigen_PC	Uncertain	0.26
FATHMM_MKL	Benign	0.49	N
LIST_S2	Benign	0.80	.;T
M_CAP	Benign	0.022	T
MetaRNN	Benign	0.34	T;T
MetaSVM	Benign	-0.92	T
MutationAssessor	Benign	1.1	L;L
MutationTaster	Benign	1.0	D
PrimateAI	Uncertain	0.49	T
PROVEAN	Benign	-0.68	N;.
REVEL	Benign	0.14
Sift	Benign	0.035	D;.
Sift4G	Benign	0.096	T;.
Polyphen		0.14	B;B
Vest4		0.53
MutPred		0.57		Loss of disorder (P = 0.0798);Loss of disorder (P = 0.0798);
MVP		0.34
MPC		0.54
ClinPred		0.62	D
GERP RS		5.4
Varity_R		0.080
gMVP		0.54

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs758092388; hg19: chr2-189975154; COSMIC: COSV66411000;