chr2-227263845-C-T

Variant summary

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

The NM_000091.5(COL4A3):​c.1216C>T​(p.Arg406*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000112 in 1,613,990 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 Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

Frequency

Genomes: 𝑓 0.000046 ( 0 hom., cov: 32)
Exomes 𝑓: 0.0000075 ( 0 hom. )

Consequence

COL4A3
NM_000091.5 stop_gained

Scores

2
1
4

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:8

Conservation

PhyloP100: 0.264
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]

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 2-227263845-C-T is Pathogenic according to our data. Variant chr2-227263845-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 495548.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-227263845-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect #exon/exons MANE Protein UniProt
COL4A3NM_000091.5 linkuse as main transcriptc.1216C>T p.Arg406* stop_gained 21/52 ENST00000396578.8 NP_000082.2 Q01955-1

Ensembl

Gene Transcript HGVSc HGVSp Effect #exon/exons TSL MANE Protein Appris UniProt
COL4A3ENST00000396578.8 linkuse as main transcriptc.1216C>T p.Arg406* stop_gained 21/521 NM_000091.5 ENSP00000379823.3 Q01955-1

Frequencies

GnomAD3 genomes
AF:
0.0000460
AC:
7
AN:
152186
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.000145
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:
0.0000160
AC:
4
AN:
249254
Hom.:
0
AF XY:
0.0000222
AC XY:
3
AN XY:
135272
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.00
Gnomad ASJ exome
AF:
0.0000994
Gnomad EAS exome
AF:
0.000111
Gnomad SAS exome
AF:
0.0000327
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000752
AC:
11
AN:
1461804
Hom.:
0
Cov.:
35
AF XY:
0.00000963
AC XY:
7
AN XY:
727218
show subpopulations
Gnomad4 AFR exome
AF:
0.0000896
Gnomad4 AMR exome
AF:
0.00
Gnomad4 ASJ exome
AF:
0.0000383
Gnomad4 EAS exome
AF:
0.0000252
Gnomad4 SAS exome
AF:
0.0000116
Gnomad4 FIN exome
AF:
0.00
Gnomad4 NFE exome
AF:
0.00000270
Gnomad4 OTH exome
AF:
0.0000331
GnomAD4 genome
AF:
0.0000460
AC:
7
AN:
152186
Hom.:
0
Cov.:
32
AF XY:
0.0000403
AC XY:
3
AN XY:
74358
show subpopulations
Gnomad4 AFR
AF:
0.000145
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:
0.0000564
Hom.:
0
Bravo
AF:
0.0000302

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:8
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Autosomal recessive Alport syndrome Pathogenic:3
Pathogenic, criteria provided, single submitterclinical testingWomen's Health and Genetics/Laboratory Corporation of America, LabCorpJun 26, 2016Variant summary: The COL4A3 c.1216C>T (p.Arg406X) variant causes a premature termination codon, predicted to cause a truncated or absent COL4A3 protein due to nonsense mediated decay, which are commonly known mechanisms for disease. The variant of interest was not observed in controls (ExAC, 1000 Gs or ESP) and has been reported in an affected individual, who was homozygous for the variant (Heidet_2001). Therefore, taking all the available lines of evidence into consideration, the variant of interest has been classified as Pathogenic. -
Likely pathogenic, no assertion criteria providedclinical testingCounsylAug 23, 2017- -
Pathogenic, criteria provided, single submitterclinical testingNeuberg Centre For Genomic Medicine, NCGM-The stop gained p.R406* in COL4A3 (NM_000091.5) has been previously reported in multiple affected individuals (Heidet L et al; Yamamura T et al). The variant has been submiited to ClinVar as Pathogenic. This variant is predicted to cause loss of normal protein function through protein truncation. Loss of function variants have been reported previously to be disease causing. For these reasons, this variant has been classified as Pathogenic. -
not provided Pathogenic:2
Pathogenic, criteria provided, single submitterclinical testingGeneDxJul 16, 2024Reported in a patient with Alport syndrome who also harbored a COL4A5 deletion in published literature (PMID: 29270492); Nonsense variant predicted to result in protein truncation or nonsense mediated decay in a gene for which loss of function is a known mechanism of disease; This variant is associated with the following publications: (PMID: 25525159, 11134255, 35675912, 29270492, 35369551, 38294522, Lee_2022_Article, 33772369) -
Pathogenic, criteria provided, single submitterclinical testingLabcorp Genetics (formerly Invitae), LabcorpJan 05, 2024This sequence change creates a premature translational stop signal (p.Arg406*) in the COL4A3 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in COL4A3 are known to be pathogenic (PMID: 8956999, 24854265, 26809805, 27281700). This variant is present in population databases (no rsID available, gnomAD 0.01%). This premature translational stop signal has been observed in individual(s) with end stage renal disease or Alport syndrome (PMID: 11134255, 29270492). ClinVar contains an entry for this variant (Variation ID: 495548). For these reasons, this variant has been classified as Pathogenic. -
COL4A3-related disorder Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingPreventionGenetics, part of Exact SciencesMar 19, 2024The COL4A3 c.1216C>T variant is predicted to result in premature protein termination (p.Arg406*). This variant has been reported in both the homozygous state and heterozygous state with a second COL4A3 mutation in multiple unrelated individuals with Alport syndrome (Heidet et al. 2001. PubMed ID: 11134255; Zhang et al. 2021. PubMed ID: 33772369; Horinouchi et al. 2020. PubMed ID: 35369551). This variant has also been reported in the heterozygous state along with a causative heterozygous COL4A5 mutation in unrelated individuals with Alport syndrome demonstrating digenic inheritance (Yamamura et al. 2017. PubMed ID: 29270492; Table S2, Savige et al. 2022. PubMed ID: 35675912). This variant is reported in 0.010% of alleles in individuals of East Asian descent in gnomAD. Nonsense variants in COL4A3 are expected to be pathogenic. This variant is interpreted as pathogenic. -
Hematuria, benign familial, 2;C5882663:Autosomal dominant Alport syndrome;C5882699:Alport syndrome 3b, autosomal recessive Pathogenic:1
Pathogenic, criteria provided, single submitterclinical testingFulgent Genetics, Fulgent GeneticsMay 01, 2024- -
Alport syndrome Pathogenic:1
Pathogenic, no assertion criteria providedclinical testingNatera, Inc.Sep 16, 2020- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.47
D
BayesDel_noAF
Pathogenic
0.27
CADD
Pathogenic
35
DANN
Uncertain
0.99
Eigen
Benign
0.0034
Eigen_PC
Benign
-0.33
FATHMM_MKL
Benign
0.093
N
Vest4
0.82
GERP RS
-0.51

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.

Other links and lift over

dbSNP: rs371334239; hg19: chr2-228128561; COSMIC: COSV67417567; COSMIC: COSV67417567; API