rs121912824

Variant summary

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

The NM_000091.5(COL4A3):c.4441C>T(p.Arg1481Ter) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000136 in 1,613,924 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 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000013 ( 0 hom. )

Consequence

COL4A3
NM_000091.5 stop_gained

Scores

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:7

Conservation

PhyloP100: 0.453

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 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 2-227307898-C-T is Pathogenic according to our data. Variant chr2-227307898-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 17484.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr2-227307898-C-T is described in Lovd as [Pathogenic]. Variant chr2-227307898-C-T is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
COL4A3	NM_000091.5 linkuse as main transcript	c.4441C>T	p.Arg1481Ter	stop_gained	48/52	ENST00000396578.8
MFF-DT	NR_102371.1 linkuse as main transcript	n.48-2243G>A		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.4441C>T	p.Arg1481Ter	stop_gained	48/52	1	NM_000091.5	P1	Q01955-1
MFF-DT	ENST00000439598.6 linkuse as main transcript	n.48-2243G>A		intron_variant, non_coding_transcript_variant		1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152170

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

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:

0.0000942

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000401

AC:

AN:

249352

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135286

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000290

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:

0.00

GnomAD4 exome

AF:

0.0000130

AC:

AN:

1461754

Hom.:

Cov.:

AF XY:

0.00000963

AC XY:

AN XY:

727190

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.0000252

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000153

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152170

Hom.:

Cov.:

AF XY:

0.0000269

AC XY:

AN XY:

74336

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.0000942

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000151

ExAC

AF:

0.00000828

AC:

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Autosomal recessive Alport syndrome

Pathogenic:3

Pathogenic, criteria provided, single submitter	clinical testing	Women's Health and Genetics/Laboratory Corporation of America, LabCorp	Jan 26, 2022	Variant summary: COL4A3 c.4441C>T (p.Arg1481X) results in a premature termination codon, predicted to cause a truncation of the encoded protein or absence of the protein due to nonsense mediated decay, which are commonly known mechanisms for disease. Truncations downstream of this position have been classified as pathogenic by our laboratory. The variant allele was found at a frequency of 4e-06 in 249352 control chromosomes. c.4441C>T has been reported in the literature in individuals affected with Alport Syndrome, Autosomal Recessive (ie. Mochizuki_1994, Vega_2003). Five clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar after 2014 without evidence for independent evaluation. All laboratories classified the variant as pathogenic. Based on the evidence outlined above, the variant was classified as pathogenic. -
Pathogenic, no assertion criteria provided	literature only	OMIM	Jan 01, 1997	- -
Pathogenic, criteria provided, single submitter	clinical testing	Counsyl	Apr 26, 2017	- -

not provided

Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	Invitae	Jan 16, 2024	This sequence change creates a premature translational stop signal (p.Arg1481*) 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). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This premature translational stop signal has been observed in individuals with Alport syndrome (PMID: 9195222, 29854973). ClinVar contains an entry for this variant (Variation ID: 17484). 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. -
Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Nov 21, 2018	The R1481X nonsense variant in the COL4A3 gene has been reported previously in association with autosomal recessive Alport syndrome (Mochizuki et al., 1994; Lemmink et al., 1994). This variant is predicted to cause loss of normal protein function either through protein truncation or nonsense-mediated mRNA decay. The variant is observed in 1/15018 (0.0067%) alleles from individuals of European background in large population cohorts (Lek et al., 2016). We consider this variant to be pathogenic. -

Alport syndrome

Pathogenic:1

Pathogenic, no assertion criteria provided

clinical testing

Natera, Inc.

Sep 16, 2020

- -

Benign familial hematuria;C4746547:Autosomal dominant Alport syndrome;C4746745:Autosomal recessive Alport syndrome

Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 19, 2021

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.54

Cadd

Pathogenic

Dann

Uncertain

1.0

Eigen

Benign

-0.042

Eigen_PC

Benign

-0.32

FATHMM_MKL

Benign

0.35

MutationTaster

Benign

1.0

Vest4

0.90

GERP RS

2.9

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.22

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.22

Position offset: 21

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