rs104886228

Positions:

• chrX-108665560-G-A
• chrX-108665560-G-T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2 PP3_Strong PP5_Very_Strong

The NM_033380.3(COL4A5):​c.3427G>A​(p.Gly1143Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,093,076 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 1 hemizygotes in GnomAD. 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)
  • Exomes 𝑓: 0.0000027 (0 hom. 1 hem.)
• Consequence: COL4A5 NM_033380.3 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:9
• Conservation: PhyloP100: 8.21

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 14 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.994
• PP5: Variant X-108665560-G-A is Pathogenic according to our data. Variant chrX-108665560-G-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 24630.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-108665560-G-A is described in Lovd as [Pathogenic]. Variant chrX-108665560-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A5	NM_033380.3	c.3427G>A	p.Gly1143Ser	missense_variant	38/53	ENST00000328300.11	NP_203699.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A5	ENST00000328300.11	c.3427G>A	p.Gly1143Ser	missense_variant	38/53	1	NM_033380.3	ENSP00000331902
COL4A5	ENST00000361603.7	c.3427G>A	p.Gly1143Ser	missense_variant	38/51	2		ENSP00000354505	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 0.00000274 AC: 3 AN: 1093076 Hom.: 0 Cov.: 28 AF XY: 0.00000279 AC XY: 1 AN XY: 358732

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: 0.00

Gnomad4 FIN exome AF: 0.0000247

Gnomad4 NFE exome AF: 0.00000239

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 23

Bravo AF: 0.00000378

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:9

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 26, 2023	ClinVar contains an entry for this variant (Variation ID: 24630). 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). 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 missense change has been observed in individual(s) with X-linked dominant Alport syndrome (PMID: 7969679). It has also been observed to segregate with disease in related individuals. This variant is not present in population databases (gnomAD no frequency). This sequence change replaces glycine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 1143 of the COL4A5 protein (p.Gly1143Ser). -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Aug 19, 2024	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 (PMID: 10752524); Reported in multiple individuals with Alport syndrome belonging to a single family in published literature; however, data is limited (PMID: 7969679, 8651296); 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: 25525159, 8651296, 7969679, 24077912, 10752524, 8249544, 31865346, 30586318, 32405592, 31027891, 35064937) -
Likely pathogenic, criteria provided, single submitter	research	Gharavi Laboratory, Columbia University	Sep 16, 2018	- -
Pathogenic, criteria provided, single submitter	clinical testing	CeGaT Center for Human Genetics Tuebingen	Sep 01, 2020	- -

X-linked Alport syndrome Pathogenic:4

Pathogenic, criteria provided, single submitter	clinical testing	Fulgent Genetics, Fulgent Genetics	May 25, 2022	- -
Pathogenic, criteria provided, single submitter	clinical testing	Molecular Diagnostics Laboratory, M Health Fairview: University of Minnesota	Feb 23, 2017	- -
Likely pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Dec 12, 2017	- -
Pathogenic, criteria provided, single submitter	clinical testing	Institute of Human Genetics Munich, Klinikum Rechts Der Isar, TU München	Mar 08, 2022	- -

COL4A5-related disorder Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Dec 12, 2023

The COL4A5 c.3427G>A variant is predicted to result in the amino acid substitution p.Gly1143Ser. This variant has been reported to be causative for X-linked Alport Syndrome (Renieri et al. 1994. PubMed ID: 7969679; Stapleton et al. 2019. PubMed ID: 31865346). The p.Gly1143Ser 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/). This variant has not been reported in a large population database, indicating this variant is rare. This variant is interpreted as pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.44
BayesDel_addAF	Pathogenic	0.74	D
BayesDel_noAF	Pathogenic	0.82
CADD	Uncertain	25
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.93	.;D
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D
M_CAP	Pathogenic	0.97	D
MetaRNN	Pathogenic	0.99	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.0	H;H
MutationTaster	Benign	1.0	A;A
PrimateAI	Pathogenic	0.81	D
PROVEAN	Pathogenic	-4.9	D;D
REVEL	Pathogenic	0.99
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.97
MutPred		1.0		Gain of glycosylation at G1143 (P = 0.0036);Gain of glycosylation at G1143 (P = 0.0036);
MVP		1.0
MPC		0.30
ClinPred		1.0	D
GERP RS		5.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.98
gMVP		1.0

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		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: rs104886228; hg19: chrX-107908790;