2-227238016-G-A

Position:

chr2-227238016-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2PP3BP4BP6

The NM_000091.5(COL4A3):c.136G>A(p.Gly46Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000102 in 1,605,096 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Synonymous variant affecting the same amino acid position (i.e. G46G) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.00060 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000050 ( 0 hom. )

Consequence

COL4A3
NM_000091.5 missense

Scores

Clinical Significance

Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:2B:3

Conservation

PhyloP100: 4.86

Variant links:

Genes affected

COL4A3 (HGNC:2204): (collagen type IV alpha 3 chain) Type IV collagen, the major structural component of basement membranes, is a multimeric protein composed of 3 alpha subunits. These subunits are encoded by 6 different genes, alpha 1 through alpha 6, each of which can form a triple helix structure with 2 other subunits to form type IV collagen. This gene encodes alpha 3. In the Goodpasture syndrome, autoantibodies bind to the collagen molecules in the basement membranes of alveoli and glomeruli. The epitopes that elicit these autoantibodies are localized largely to the non-collagenous C-terminal domain of the protein. A specific kinase phosphorylates amino acids in this same C-terminal region and the expression of this kinase is upregulated during pathogenesis. This gene is also linked to an autosomal recessive form of Alport syndrome. The mutations contributing to this syndrome are also located within the exons that encode this C-terminal region. 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. [provided by RefSeq, Jun 2010]

COL4A3 links:

MFF-DT (HGNC:41067): (MFF divergent transcript)

MFF-DT links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP3

Multiple lines of computational evidence support a deleterious effect 7: AlphaMissense, BayesDel_noAF, Eigen, M_CAP, MutationAssessor, PROVEAN, REVEL [when max_spliceai, FATHMM_MKL, MetaRNN, MutationTaster was below the threshold]

BP4

Computational evidence support a benign effect (MetaRNN=0.29928488).

BP6

Variant 2-227238016-G-A is Benign according to our data. Variant chr2-227238016-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 684144.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=2, Uncertain_significance=1}. Variant chr2-227238016-G-A is described in Lovd as [Likely_benign].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL4A3	NM_000091.5 linkuse as main transcript	c.136G>A	p.Gly46Arg	missense_variant	2/52	ENST00000396578.8
MFF-DT	NR_102371.1 linkuse as main transcript	n.1681+70C>T		intron_variant, non_coding_transcript_variant

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
COL4A3	ENST00000396578.8 linkuse as main transcript	c.136G>A	p.Gly46Arg	missense_variant	2/52	1	NM_000091.5	P1	Q01955-1
MFF-DT	ENST00000439598.6 linkuse as main transcript	n.1681+70C>T		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes

AF:

0.000598

AC:

AN:

152130

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.00210

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.000262

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:

0.00

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.000164

AC:

AN:

249530

Hom.:

AF XY:

0.000126

AC XY:

AN XY:

135380

show subpopulations

Gnomad AFR exome

AF:

0.00245

Gnomad AMR exome

AF:

0.0000579

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.000165

GnomAD4 exome

AF:

0.0000496

AC:

AN:

1452848

Hom.:

Cov.:

AF XY:

0.0000498

AC XY:

AN XY:

723394

show subpopulations

Gnomad4 AFR exome

AF:

0.00177

Gnomad4 AMR exome

AF:

0.0000895

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:

0.00

Gnomad4 OTH exome

AF:

0.000150

GnomAD4 genome

AF:

0.000598

AC:

AN:

152248

Hom.:

Cov.:

AF XY:

0.000645

AC XY:

AN XY:

74442

show subpopulations

Gnomad4 AFR

AF:

0.00209

Gnomad4 AMR

AF:

0.000262

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.00

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000105

Hom.:

Bravo

AF:

0.000680

ESP6500AA

AF:

0.00243

AC:

ESP6500EA

AF:

0.00

AC:

ExAC

AF:

0.000232

AC:

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:2Benign:3

Revision: criteria provided, conflicting classifications

LINK: link

Submissions by phenotype

not provided

Benign:2

Likely benign, criteria provided, single submitter	clinical testing	GeneDx	Jul 20, 2020	- -
Likely benign, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Jan 27, 2024	- -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 13, 2022

The c.136G>A (p.G46R) alteration is located in exon 2 (coding exon 2) of the COL4A3 gene. This alteration results from a G to A substitution at nucleotide position 136, causing the glycine (G) at amino acid position 46 to be replaced by an arginine (R). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Autosomal dominant Alport syndrome

Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

Natera, Inc.

Apr 24, 2020

- -

COL4A3-related disorder

Benign:1

Likely benign, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Apr 15, 2021

This variant is classified as likely benign based on ACMG/AMP sequence variant interpretation guidelines (Richards et al. 2015 PMID: 25741868, with internal and published modifications). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.69

BayesDel_addAF

Uncertain

0.056

BayesDel_noAF

Pathogenic

0.30

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.54

Eigen

Pathogenic

0.86

Eigen_PC

Pathogenic

0.70

FATHMM_MKL

Uncertain

0.82

LIST_S2

Pathogenic

0.98

M_CAP

Pathogenic

0.83

MetaRNN

Benign

0.30

MetaSVM

Pathogenic

1.0

MutationAssessor

Pathogenic

4.5

MutationTaster

Benign

1.0

PrimateAI

Uncertain

0.68

PROVEAN

Pathogenic

-6.3

REVEL

Pathogenic

0.79

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0

Polyphen

1.0

Vest4

0.68

MutPred

0.83

Loss of sheet (P = 0.0104);

MVP

0.88

MPC

0.83

ClinPred

0.28

GERP RS

5.4

Varity_R

0.94

gMVP

0.89

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

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