X-108580721-G-A

Position:

• chrX-108580721-G-A

Variant summary

Our verdict is Pathogenic. Variant got 16 ACMG points: 16P and 0B. PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_033380.3(COL4A5):​c.874G>A​(p.Gly292Arg) 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. Variant has been reported in ClinVar as Likely pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G292V) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 23)
• Consequence: COL4A5 NM_033380.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:4
• Conservation: PhyloP100: 8.12

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]

ACMG classification

Verdict is Pathogenic. Variant got 16 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrnull-null-null-null is described in UniProt as null.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.995
• PP5: Variant X-108580721-G-A is Pathogenic according to our data. Variant chrX-108580721-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1076557.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A5	NM_033380.3	c.874G>A	p.Gly292Arg	missense_variant	15/53	ENST00000328300.11	NP_203699.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A5	ENST00000328300.11	c.874G>A	p.Gly292Arg	missense_variant	15/53	1	NM_033380.3	ENSP00000331902.7
COL4A5	ENST00000361603.7	c.874G>A	p.Gly292Arg	missense_variant	15/51	2		ENSP00000354505.2

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 23

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Dec 27, 2022	Reported in a family with Alport syndrome in published literature (Bekheirnia et al., 2010); Affects a glycine residue in a Gly-X-Y motif in the triple helical region of the COL4A5 gene, where the majority of pathogenic missense variants occur, and is predicted to disrupt normal protein folding and function (HGMD; Jais et al., 2000); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 20378821, 10752524) -
Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 11, 2023	This sequence change replaces glycine, which is neutral and non-polar, with arginine, which is basic and polar, at codon 292 of the COL4A5 protein (p.Gly292Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with X-linked Alport syndrome (PMID: 20378821). ClinVar contains an entry for this variant (Variation ID: 1076557). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt COL4A5 protein function. 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). For these reasons, this variant has been classified as Pathogenic. -
Pathogenic, criteria provided, single submitter	clinical testing	Athena Diagnostics	Jun 14, 2021	This variant has not been reported in large, multi-ethnic general populations (http://gnomad.broadinstitute.org). This variant has been identified in at least one individual with clinical features associated with this gene. At least one other missense variant at this codon is considered to be pathogenic or likely pathogenic, suggesting this variant may also cause disease. This variant alters a critical location within the protein, and is expected to severely affect function and cause disease. -
Likely pathogenic, criteria provided, single submitter	clinical testing	Mayo Clinic Laboratories, Mayo Clinic	Oct 13, 2022	PP3, PM1, PM2_supporting, PS4_moderate -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.82
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.93	.;D
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	1.0	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.2	H;H
PrimateAI	Pathogenic	0.82	D
PROVEAN	Pathogenic	-7.6	D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.99
MutPred		1.0		Gain of MoRF binding (P = 0.0157);Gain of MoRF binding (P = 0.0157);
MVP		1.0
MPC		0.36
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.99
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		Details are displayed if max score is > 0.2

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

Publications

No publications associated with this variant yet.

Other links and lift over

hg19: chrX-107823951; COSMIC: COSV100086984; COSMIC: COSV100086984;