chr3-121828519-G-A

Variant names:

Variant summary

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

The NM_001023570.4(IQCB1):c.214C>T(p.Arg72*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000899 in 1,612,894 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 0.000072 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000092 ( 0 hom. )

Consequence

IQCB1
NM_001023570.4 stop_gained

Scores

Clinical Significance

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

Conservation

PhyloP100: 2.49

Variant links:

Genes affected

IQCB1 (HGNC:28949): (IQ motif containing B1) This gene encodes a nephrocystin protein that interacts with calmodulin and the retinitis pigmentosa GTPase regulator protein. The encoded protein has a central coiled-coil region and two calmodulin-binding IQ domains. It is localized to the primary cilia of renal epithelial cells and connecting cilia of photoreceptor cells. The protein is thought to play a role in ciliary function. Defects in this gene result in Senior-Loken syndrome type 5. Alternative splicing results in multiple transcript variants. A pseudogene of this gene is found on chromosome 6. [provided by RefSeq, Jan 2016]

IQCB1 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 3-121828519-G-A is Pathogenic according to our data. Variant chr3-121828519-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 285623.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr3-121828519-G-A is described in Lovd as [Likely_pathogenic]. Variant chr3-121828519-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IQCB1	NM_001023570.4 link	c.214C>T	p.Arg72*	stop_gained	Exon 4 of 15	ENST00000310864.11	NP_001018864.2	Q15051-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IQCB1	ENST00000310864.11 link	c.214C>T	p.Arg72*	stop_gained	Exon 4 of 15	1	NM_001023570.4	ENSP00000311505.6		Q15051-1

Frequencies

GnomAD3 genomes

AF:

0.0000723

AC:

AN:

152056

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000483

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.000118

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000358

AC:

AN:

251296

Hom.:

AF XY:

0.0000295

AC XY:

AN XY:

135806

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:

0.0000616

Gnomad OTH exome

AF:

0.000326

GnomAD4 exome

AF:

0.0000917

AC:

134

AN:

1460720

Hom.:

Cov.:

AF XY:

0.0000936

AC XY:

AN XY:

726750

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.0000224

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000114

Gnomad4 OTH exome

AF:

0.0000994

GnomAD4 genome

AF:

0.0000723

AC:

AN:

152174

Hom.:

Cov.:

AF XY:

0.0000672

AC XY:

AN XY:

74402

show subpopulations

Gnomad4 AFR

AF:

0.0000482

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.000118

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.0000636

Hom.:

Bravo

AF:

0.0000453

ESP6500AA

AF:

0.00

AC:

ESP6500EA

AF:

0.000116

AC:

ExAC

AF:

0.0000165

AC:

EpiCase

AF:

0.000164

EpiControl

AF:

0.0000593

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:7

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Senior-Loken syndrome 5

Pathogenic:2

Mar 11, 2024

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

May 27, 2022

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Leber congenital amaurosis

Pathogenic:2

Jan 01, 2015

NIHR Bioresource Rare Diseases, University of Cambridge

Significance: Likely pathogenic

Review Status: no assertion criteria provided

Collection Method: research

- -

Jun 18, 2021

DBGen Ocular Genomics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided

Pathogenic:2

Oct 23, 2020

Institute of Medical Genetics and Applied Genomics, University Hospital Tübingen

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 05, 2016

Eurofins Ntd Llc (ga)

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Nephronophthisis

Pathogenic:1

Oct 27, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Arg72*) in the IQCB1 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in IQCB1 are known to be pathogenic (PMID: 15723066, 21901789, 23559409, 28041643). This variant is present in population databases (rs201405662, gnomAD 0.008%). This premature translational stop signal has been observed in individual(s) with early onset retinal disease (PMID: 28041643, 28559085). ClinVar contains an entry for this variant (Variation ID: 285623). 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. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.49

BayesDel_noAF

Pathogenic

0.58

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

0.80

Eigen_PC

Pathogenic

0.67

FATHMM_MKL

Benign

0.75

Vest4

0.43

GERP RS

4.4

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.16

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