rs281874715

Variant names:

• chrX-108665588-G-A
• rs281874715
• NM_033380.3:c.3454+1G>A

Your query was ambiguous. Multiple possible variants found:

• chrX-108665588-G-A
• chrX-108665588-G-T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_033380.3(COL4A5):​c.3454+1G>A variant causes a splice donor, intron 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: COL4A5 NM_033380.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 7.93
• Publications: 0 publications found

Genes affected

COL4A5 (HGNC:2207): (collagen type IV alpha 5 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. Mutations in this gene are associated with X-linked Alport syndrome, also known as hereditary nephritis. Like the other members of the type IV collagen gene family, this gene is organized in a head-to-head conformation with another type IV collagen gene so that each gene pair shares a common promoter. Alternatively spliced transcript variants have been identified for this gene. [provided by RefSeq, Aug 2010]

COL4A5 Gene-Disease associations (from GenCC):

• Alport syndrome

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen, G2P
• X-linked Alport syndrome

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: PanelApp Australia, Genomics England PanelApp, Myriad Women’s Health, Orphanet, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.015957447 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant X-108665588-G-A is Pathogenic according to our data. Variant chrX-108665588-G-A is described in ClinVar as Pathogenic. ClinVar VariationId is 2022873.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL4A5	NM_033380.3	c.3454+1G>A		splice_donor_variant, intron_variant	Intron 38 of 52	ENST00000328300.11	NP_203699.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL4A5	ENST00000328300.11	c.3454+1G>A		splice_donor_variant, intron_variant	Intron 38 of 52	1	NM_033380.3	ENSP00000331902.7
COL4A5	ENST00000361603.7	c.3454+1G>A		splice_donor_variant, intron_variant	Intron 38 of 50	2		ENSP00000354505.2

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 24

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Apr 30, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

For these reasons, this variant has been classified as Pathogenic. This variant disrupts the triple helix domain of COL4A5. Glycine residues within the Gly-Xaa-Yaa repeats of the triple helix domain are required for the structure and stability of fibrillar collagens (PMID: 7695699, 8218237, 19344236). In COL4A5, missense variants at these glycine residues are significantly enriched in individuals with disease (PMID: 23720012, 27627812) compared to the general population (ExAC). Studies have shown that disruption of this splice site results in skipping of exon 38, but is expected to preserve the integrity of the reading-frame (PMID: 8441246). ClinVar contains an entry for this variant (Variation ID: 2022873). Disruption of this splice site has been observed in individual(s) with clinical features of Alport syndrome (PMID: 8441246, 9848783). This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 38 of the COL4A5 gene. RNA analysis indicates that disruption of this splice site induces altered splicing and likely results in a shortened protein product. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.37
CADD	Pathogenic	30
DANN	Uncertain	1.0
FATHMM_MKL	Pathogenic	0.99	D
PhyloP100		7.9
GERP RS		5.5
Mutation Taster		=0/100	disease causing

Splicing

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

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

Other links and lift over

dbSNP: rs281874715; hg19: chrX-107908818;