2-227089922-C-A

Position:

chr2-227089922-C-A

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PVS1PM2PP5_Very_Strong

The NM_000092.5(COL4A4):c.1405G>T(p.Gly469Ter) variant causes a stop gained change. The variant allele was found at a frequency of 0.00000124 in 1,613,470 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 31)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

COL4A4
NM_000092.5 stop_gained

Scores

Clinical Significance

Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:3

Conservation

PhyloP100: 4.18

Variant links:

Genes affected

COL4A4 (HGNC:2206): (collagen type IV alpha 4 chain) This gene encodes one of the six subunits of type IV collagen, the major structural component of basement membranes. This particular collagen IV subunit, however, is only found in a subset of basement membranes. 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. Mutations in this gene are associated with type II autosomal recessive Alport syndrome (hereditary glomerulonephropathy) and with familial benign hematuria (thin basement membrane disease). Two transcripts, differing only in their transcription start sites, have been identified for this gene and, as is common for collagen genes, multiple polyadenylation sites are found in the 3' UTR. [provided by RefSeq, Jul 2008]

COL4A4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Pathogenic. Variant got 18 ACMG points.

PVS1

Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 2-227089922-C-A is Pathogenic according to our data. Variant chr2-227089922-C-A is described in ClinVar as [Likely_pathogenic]. Clinvar id is 553870.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-227089922-C-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A4	NM_000092.5 linkuse as main transcript	c.1405G>T	p.Gly469Ter	stop_gained	21/48	ENST00000396625.5	NP_000083.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A4	ENST00000396625.5 linkuse as main transcript	c.1405G>T	p.Gly469Ter	stop_gained	21/48	5	NM_000092.5	ENSP00000379866	P1

Frequencies

GnomAD3 genomes

AF:

0.00000658

AC:

AN:

151924

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461546

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727102

show subpopulations

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:

0.00

Gnomad4 NFE exome

AF:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000658

AC:

AN:

151924

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74168

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000329

Hom.:

Bravo

AF:

0.0000151

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal recessive Alport syndrome

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Counsyl

Sep 16, 2017

- -

not provided

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 09, 2022

This sequence change creates a premature translational stop signal (p.Gly469*) in the COL4A4 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL4A4 are known to be pathogenic (PMID: 21196518, 24854265, 25307543). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with clinical features of Alport syndrome (PMID: 15954103). ClinVar contains an entry for this variant (Variation ID: 553870). 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. -

Autosomal dominant Alport syndrome

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Molecular Genetics, Royal Melbourne Hospital

Mar 30, 2023

This sequence change in COL4A4 is a nonsense variant predicted to cause a premature stop codon (p.(Gly469*)) in biologically-relevant-exon 21/48 leading to nonsense mediated decay in a gene in which loss-of-function is an established disease mechanism (PMID: 20301386). This variant is present in a single European (non-Finnish) individual in gnomAD v2.1 (1/67,998 alleles). This variant has been reported in at least two probands with a phenotype consistent with autosomal dominant Alport syndrome (PMID: 15954103; Royal Melbourne Hospital). Based on the classification scheme RMH Modified ACMG Guidelines v1.4.0, this variant is classified as PATHOGENIC. Following criteria are met: PVS1, PS4_Supporting, PM2_Supporting. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.63

CADD

Pathogenic

DANN

Uncertain

0.99

Eigen

Pathogenic

0.94

Eigen_PC

Pathogenic

0.75

FATHMM_MKL

Uncertain

0.95

MutationTaster

Benign

1.0

A;A

Vest4

0.75

GERP RS

6.0

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.25

Details are displayed if max score is > 0.2

DS_AL_spliceai

0.25

Position offset: 35

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over