2-227098769-G-A

Position:

chr2-227098769-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_000092.5(COL4A4):c.1129C>T(p.Arg377Cys) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000018 in 1,614,028 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

Frequency

Genomes: 𝑓 0.000066 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

COL4A4
NM_000092.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:5B:1

Conservation

PhyloP100: 1.67

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:

COL4A4 (HGNC:):

COL4A4 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 2 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A4	NM_000092.5 linkuse as main transcript	c.1129C>T	p.Arg377Cys	missense_variant	19/48	ENST00000396625.5	NP_000083.3	P53420

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A4	ENST00000396625.5 linkuse as main transcript	c.1129C>T	p.Arg377Cys	missense_variant	19/48	5	NM_000092.5	ENSP00000379866.3		P53420

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152148

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.000169

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

GnomAD3 exomes

AF:

0.0000362

AC:

AN:

248596

Hom.:

AF XY:

0.0000370

AC XY:

AN XY:

135050

show subpopulations

Gnomad AFR exome

AF:

0.000195

Gnomad AMR exome

AF:

0.0000580

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.0000981

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00000888

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461762

Hom.:

Cov.:

AF XY:

0.0000138

AC XY:

AN XY:

727202

show subpopulations

Gnomad4 AFR exome

AF:

0.0000896

Gnomad4 AMR exome

AF:

0.0000447

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.0000580

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.00000630

Gnomad4 OTH exome

AF:

0.0000166

GnomAD4 genome

AF:

0.0000657

AC:

AN:

152266

Hom.:

Cov.:

AF XY:

0.0000806

AC XY:

AN XY:

74446

show subpopulations

Gnomad4 AFR

AF:

0.000217

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:

0.0000987

Hom.:

Bravo

AF:

0.0000680

ExAC

AF:

0.0000414

AC:

EpiCase

AF:

0.00

EpiControl

AF:

0.0000593

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:5Benign:1

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Uncertain:1Benign:1

Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 08, 2024	- -
Uncertain significance, criteria provided, single submitter	clinical testing	GeneDx	May 31, 2022	Reported in a patient with microtia in published literature (Wang et al., 2017); In silico analysis supports that this missense variant does not alter protein structure/function; Occurs in the triple helical domain at the X position in the canonical Gly-X-Y repeat; although this variant may have an effect on normal protein folding and function, missense substitution at the X position is not a common mechanism of disease; This variant is associated with the following publications: (PMID: 28968992) -

not specified

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Laboratory for Molecular Medicine, Mass General Brigham Personalized Medicine

Mar 21, 2018

The p.Arg377Cys variant in COL4A4 has not been previously reported in individual s with hearing loss or Alport syndrome. This variant is present in 0.03% (6/2392 ) African chromosomes by the Genome Aggregation Database (gnomAD, http://gnomad. broadinstitute.org; dbSNP rs555143841). Although this variant has been seen in t he general population, its frequency is not high enough to rule out a pathogenic role. Computational prediction tools and conservation analyses do not provide s trong support for or against an impact to the protein. In summary, the clinical significance of the p.Arg377Cys variant is uncertain. ACMG/AMP criteria applied : PM2_Supporting. -

Autosomal recessive Alport syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Counsyl

Apr 02, 2018

- -

Benign familial hematuria;C4746745:Autosomal recessive Alport syndrome

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Jan 28, 2022

- -

Alport syndrome

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Sep 16, 2020

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.096

BayesDel_addAF

Benign

-0.11

BayesDel_noAF

Benign

-0.11

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.34

Eigen

Uncertain

0.23

Eigen_PC

Benign

0.16

FATHMM_MKL

Benign

0.67

LIST_S2

Uncertain

0.94

M_CAP

Uncertain

0.18

MetaRNN

Uncertain

0.44

MetaSVM

Uncertain

0.19

MutationAssessor

Uncertain

2.1

PrimateAI

Benign

0.33

PROVEAN

Benign

-1.2

REVEL

Uncertain

0.47

Sift

Benign

0.17

Sift4G

Benign

0.18

Polyphen

0.99

Vest4

0.25

MVP

0.84

MPC

0.64

ClinPred

0.25

GERP RS

2.6

Varity_R

0.065

gMVP

0.36

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

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