rs886042173

chr9-134763738-G-A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PVS1_Moderate PM2 PP3_Strong PP5_Very_Strong

The NM_000093.5(COL5A1):c.2034+1G>A variant causes a splice donor change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: COL5A1 NM_000093.5 splice_donor
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 5.76

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]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PVS1: Splicing variant, NOT destroyed by nmd, known LOF gene, truncates exone, which is 0.007975349 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.3, offset of 8, new splice context is: tctGTgagc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF, max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.
• PP5: Variant 9-134763738-G-A is Pathogenic according to our data. Variant chr9-134763738-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 281486.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr9-134763738-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL5A1	NM_000093.5	c.2034+1G>A		splice_donor_variant		ENST00000371817.8
COL5A1	NM_001278074.1	c.2034+1G>A		splice_donor_variant
COL5A1	XM_017014266.3	c.2034+1G>A		splice_donor_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL5A1	ENST00000371817.8	c.2034+1G>A		splice_donor_variant		1	NM_000093.5	P4
COL5A1	ENST00000371820.4	c.2034+1G>A		splice_donor_variant		2		A2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Jan 27, 2020	Has not been previously published as pathogenic or benign to our knowledge; Reported in ClinVar as pathogenic (ClinVar Variant ID# 281486; Landrum et al., 2016); Not observed in large population cohorts (Lek et al., 2016); Damages or destroys the splice donor site in intron 20, and is expected to cause abnormal gene splicing; if the splice outcome is exon skip, the loss of the encoded residues in the triple helical region is expected to disrupt normal protein folding and function (Symoens et al., 2012; Stenson et al., 2014); This variant is associated with the following publications: (PMID: 23587214) -
Pathogenic, criteria provided, single submitter	clinical testing	Eurofins Ntd Llc (ga)	Jun 23, 2015	- -

Ehlers-Danlos syndrome Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genome Diagnostics Laboratory, The Hospital for Sick Children

Dec 01, 2018

- -

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

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Oct 04, 2023

This sequence change affects a donor splice site in intron 20 of the COL5A1 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in COL5A1 are known to be pathogenic (PMID: 23587214). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individuals with clinical features consistent with Ehlers-Danlos syndrome (PMID: 27011056, 34265140; Invitae). ClinVar contains an entry for this variant (Variation ID: 281486). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.090
Cadd	Pathogenic	30
Dann	Uncertain	0.99
Eigen	Pathogenic	0.87
Eigen_PC	Uncertain	0.64
FATHMM_MKL	Uncertain	0.96	D
MutationTaster	Benign	1.0	D
GERP RS		3.9

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.94		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.24		Position offset: 7
DS_DL_spliceai		0.94		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs886042173; hg19: chr9-137655584; COSMIC: COSV65670134;