2-227303867-G-T

Position:

chr2-227303867-G-T

Variant summary

Our verdict is Pathogenic. Variant got 14 ACMG points: 14P and 0B. PM2PP3_StrongPP5_Very_Strong

The NM_000091.5(COL4A3):c.3964G>T(p.Gly1322Cys) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,734 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 (★★).

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

COL4A3
NM_000091.5 missense

Scores

Clinical Significance

Likely pathogenic criteria provided, multiple submitters, no conflicts P:2

Conservation

PhyloP100: 6.09

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:):

MFF-DT links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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, 0.995

PP5

Variant 2-227303867-G-T is Pathogenic according to our data. Variant chr2-227303867-G-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 3061902.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL4A3	NM_000091.5 linkuse as main transcript	c.3964G>T	p.Gly1322Cys	missense_variant	45/52	ENST00000396578.8	NP_000082.2	Q01955-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL4A3	ENST00000396578.8 linkuse as main transcript	c.3964G>T	p.Gly1322Cys	missense_variant	45/52	1	NM_000091.5	ENSP00000379823.3		Q01955-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000401

AC:

AN:

249066

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135164

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

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:

0.00000886

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461734

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

727170

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

Cov.:

ExAC

AF:

0.00000828

AC:

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Alport syndrome

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Jul 17, 2023

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely pathogenic. Following criteria are met: 0103 - Dominant negative and loss of function are known mechanisms of disease in this gene and are associated with COL4A3-related nephropathy. Glycine changes that are part of a G-X-Y repeat in the triple helix of a collagen domain are known to have a dominant negative effect (PMID: 12028435). (I) 0108 - This gene is associated with both recessive (Alport syndrome 2 MIM#203780) and dominant disease (Alport syndrome 3 MIM#104200 and benign familial haematuria MIM#141200) (OMIM). (I) 0200 - Variant is predicted to result in a missense amino acid change from glycine to cysteine. (I) 0251 - This variant is heterozygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 (1 heterozygote, 0 homozygotes). (SP) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0601 - Variant is located in the well-established functional Gly-X-Y motif within the collagen repeat domain, and affects a glycine residue (DECIPHER). (SP) 0710 - Another missense variant comparable to the one identified in this case has inconclusive previous evidence for pathogenicity. One paper downgraded the classification of p.(Gly1322Ser) from likely pathogenic to a VUS due to its frequency in their cohort, however it is not clear how many individuals in this cohort had this variant or what their phenotypes were (PMID: 31130284). (I) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1208 - Inheritance information for this variant is not currently available in this individual. (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign -

Autosomal dominant Alport syndrome

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

MVZ Medizinische Genetik Mainz

Jul 26, 2023

PM1_STR,PM2_SUP,PP3,PP4 -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Pathogenic

0.81

BayesDel_addAF

Pathogenic

0.56

BayesDel_noAF

Pathogenic

0.56

CADD

Pathogenic

DANN

Uncertain

0.99

DEOGEN2

Uncertain

0.68

Eigen

Pathogenic

1.1

Eigen_PC

Pathogenic

0.97

FATHMM_MKL

Pathogenic

0.98

LIST_S2

Pathogenic

0.99

M_CAP

Pathogenic

0.70

MetaRNN

Pathogenic

0.99

MetaSVM

Pathogenic

0.97

MutationAssessor

Pathogenic

4.8

PrimateAI

Uncertain

0.72

PROVEAN

Pathogenic

-7.9

REVEL

Pathogenic

0.96

Sift

Pathogenic

0.0

Sift4G

Pathogenic

0.0010

Polyphen

1.0

Vest4

0.95

MutPred

0.99

Gain of methylation at K1321 (P = 0.0225);

MVP

0.95

MPC

0.20

ClinPred

1.0

GERP RS

5.6

Varity_R

0.99

gMVP

0.86

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