X-108687508-G-T

Variant names:

• chrX-108687508-G-T
• NM_033380.3:c.4342G>T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PP3_Strong PP5_Moderate

The NM_033380.3(COL4A5):​c.4342G>T​(p.Gly1448Cys) 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 (★).

• Frequency: Genomes: not found (cov: 23)
• Consequence: COL4A5 NM_033380.3 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 10.0

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 Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.981
• PP5: Variant X-108687508-G-T is Pathogenic according to our data. Variant chrX-108687508-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 2633972.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.4342G>T	p.Gly1448Cys	missense_variant	Exon 49 of 53	ENST00000328300.11	NP_203699.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL4A5	ENST00000328300.11	c.4342G>T	p.Gly1448Cys	missense_variant	Exon 49 of 53	1	NM_033380.3	ENSP00000331902.7

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 23

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

COL4A5-related disorder Pathogenic:1

Oct 03, 2023

PreventionGenetics, part of Exact Sciences

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The COL4A5 c.4324G>T variant is predicted to result in the amino acid substitution p.Gly1442Cys. The p.Gly1442 residue resides in the triple-helical region (residues 42 – 1456) of the COL4A5 protein (uniprot.org). The majority of pathogenic variants in COL4A5 substitute a glycine residue to a bulkier amino acid in the triple-helical domain (Hudson et al. 1993. PubMed ID: 8253711; https://www.ncbi.nlm.nih.gov/books/NBK1207/). Other amino acid substitutions at this position (p.Gly1442Arg, p.Gly1442Ser, p.Gly1442Asp) have been reported in individuals with COL4A5-related disorders (eg. King et al 2006. PubMed ID: 16941480; Boeckhaus et al 2021. PubMed ID: 33040356; Plant et al 1999. PubMed ID: 10094548). To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. This variant is interpreted as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.95
BayesDel_addAF	Pathogenic	0.68	D
BayesDel_noAF	Pathogenic	0.74
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.94	.;D
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.94	D
MetaRNN	Pathogenic	0.98	D;D
MetaSVM	Pathogenic	0.94	D
MutationAssessor	Pathogenic	4.4	.;H
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-7.5	D;D
REVEL	Pathogenic	0.92
Sift	Uncertain	0.0020	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.97
MutPred		0.78		.;Loss of catalytic residue at G1439 (P = 0.3112);
MVP		0.97
MPC		1.1
ClinPred		1.0	D
GERP RS		5.6
Varity_R		0.98
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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-107930738;