rs121918245

Positions:

• chr3-121790133-G-A
• chr3-121790133-G-C

Variant summary

Our verdict is Pathogenic. Variant got 11 ACMG points: 11P and 0B. PVS1 PM2 PP5

The ENST00000310864.11(IQCB1):​c.1069C>T​(p.Gln357Ter) variant causes a stop gained change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (no stars). Variant results in nonsense mediated mRNA decay.

• Frequency: Genomes: not found (cov: 32)
• Consequence: IQCB1 ENST00000310864.11 stop_gained
• Clinical Significance: Pathogenic no assertion criteria provided P:1
• Conservation: PhyloP100: 5.44

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]

ACMG classification

Verdict is Pathogenic. Variant got 11 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 3-121790133-G-A is Pathogenic according to our data. Variant chr3-121790133-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 1834.Status of the report is no_assertion_criteria_provided, 0 stars. Variant chr3-121790133-G-A is described in Lovd as [Likely_pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IQCB1	NM_001023570.4	c.1069C>T	p.Gln357Ter	stop_gained	11/15	ENST00000310864.11	NP_001018864.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IQCB1	ENST00000310864.11	c.1069C>T	p.Gln357Ter	stop_gained	11/15	1	NM_001023570.4	ENSP00000311505	P1
IQCB1	ENST00000349820.10	c.670C>T	p.Gln224Ter	stop_gained	8/12	1		ENSP00000323756
IQCB1	ENST00000393650.7	c.*47C>T		3_prime_UTR_variant, NMD_transcript_variant	10/14	5		ENSP00000377261

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: no assertion criteria provided

Submissions by phenotype

Senior-Loken syndrome 5 Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Mar 01, 2005

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.63
CADD	Pathogenic	39
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Uncertain	0.94	D
MutationTaster	Benign	1.0	A;A
Vest4		0.29
GERP RS		4.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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

Other links and lift over

dbSNP: rs121918245; hg19: chr3-121508980;