chr3-121828519-G-C

Position:

chr3-121828519-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2BP4

The NM_001023570.4(IQCB1):c.214C>G(p.Arg72Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000806 in 1,612,776 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 Uncertain significance (★★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

IQCB1
NM_001023570.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:2

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:

IQCB1 (HGNC:):

IQCB1 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;

BP4

Computational evidence support a benign effect (MetaRNN=0.30307823).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IQCB1	NM_001023570.4 linkuse as main transcript	c.214C>G	p.Arg72Gly	missense_variant	4/15	ENST00000310864.11	NP_001018864.2	Q15051-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IQCB1	ENST00000310864.11 linkuse as main transcript	c.214C>G	p.Arg72Gly	missense_variant	4/15	1	NM_001023570.4	ENSP00000311505.6		Q15051-1

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152056

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000242

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.0000655

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:

0.00000796

AC:

AN:

251296

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135806

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000289

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:

0.00000880

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000685

AC:

AN:

1460720

Hom.:

Cov.:

AF XY:

0.00000550

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:

0.00000630

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152056

Hom.:

Cov.:

AF XY:

0.00

AC XY:

AN XY:

74274

show subpopulations

Gnomad4 AFR

AF:

0.0000242

Gnomad4 AMR

AF:

0.0000655

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

Bravo

AF:

0.0000227

EpiCase

AF:

0.0000545

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Senior-Loken syndrome 5

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Dec 02, 2021

- -

Nephronophthisis

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 08, 2022

This sequence change replaces arginine, which is basic and polar, with glycine, which is neutral and non-polar, at codon 72 of the IQCB1 protein (p.Arg72Gly). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with IQCB1-related conditions. ClinVar contains an entry for this variant (Variation ID: 1039328). Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.13

BayesDel_addAF

Uncertain

0.095

BayesDel_noAF

Uncertain

-0.020

CADD

Benign

DANN

Uncertain

1.0

DEOGEN2

Benign

0.20

T;.;.

Eigen

Uncertain

0.34

Eigen_PC

Uncertain

0.41

FATHMM_MKL

Uncertain

0.76

LIST_S2

Benign

0.80

T;T;T

M_CAP

Benign

0.024

MetaRNN

Benign

0.30

T;T;T

MetaSVM

Benign

-0.41

MutationAssessor

Benign

1.5

L;L;.

PrimateAI

Uncertain

0.51

PROVEAN

Uncertain

-2.7

D;D;D

REVEL

Benign

0.23

Sift

Benign

0.12

T;D;T

Sift4G

Benign

0.13

T;T;.

Polyphen

0.99

D;P;.

Vest4

0.61

MutPred

0.43

Gain of loop (P = 0.0166);Gain of loop (P = 0.0166);Gain of loop (P = 0.0166);

MVP

0.90

MPC

0.31

ClinPred

0.91

GERP RS

4.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.23

gMVP

0.36

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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