rs387907009

Variant summary

Our verdict is Pathogenic. The variant received 16 ACMG points: 16P and 0B. PVS1PP5_Very_Strong

The NM_001023570.4(IQCB1):​c.1036G>T​(p.Glu346*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000198 in 1,461,368 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: not found (cov: 32)
Exomes 𝑓: 0.000020 ( 0 hom. )

Consequence

IQCB1
NM_001023570.4 stop_gained

Scores

2
4
1

Clinical Significance

Pathogenic criteria provided, multiple submitters, no conflicts P:6

Conservation

PhyloP100: 1.77

Publications

10 publications found
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 Gene-Disease associations (from GenCC):
  • Senior-Loken syndrome 5
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
  • Leber congenital amaurosis
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
  • Senior-Loken syndrome
    Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 16 ACMG points.

PVS1
Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
PP5
Variant 3-121790166-C-A is Pathogenic according to our data. Variant chr3-121790166-C-A is described in ClinVar as Pathogenic. ClinVar VariationId is 30779.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
IQCB1NM_001023570.4 linkc.1036G>T p.Glu346* stop_gained Exon 11 of 15 ENST00000310864.11 NP_001018864.2 Q15051-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
IQCB1ENST00000310864.11 linkc.1036G>T p.Glu346* stop_gained Exon 11 of 15 1 NM_001023570.4 ENSP00000311505.6 Q15051-1
IQCB1ENST00000349820.10 linkc.637G>T p.Glu213* stop_gained Exon 8 of 12 1 ENSP00000323756.7 Q15051-2
IQCB1ENST00000393650.7 linkn.*14G>T non_coding_transcript_exon_variant Exon 10 of 14 5 ENSP00000377261.3 Q15051-3
IQCB1ENST00000393650.7 linkn.*14G>T 3_prime_UTR_variant Exon 10 of 14 5 ENSP00000377261.3 Q15051-3

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000119
AC:
3
AN:
251416
AF XY:
0.00
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 FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000176
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000198
AC:
29
AN:
1461368
Hom.:
0
Cov.:
30
AF XY:
0.0000151
AC XY:
11
AN XY:
727016
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33468
American (AMR)
AF:
0.00
AC:
0
AN:
44722
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26128
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39664
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86234
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5764
European-Non Finnish (NFE)
AF:
0.0000234
AC:
26
AN:
1111600
Other (OTH)
AF:
0.0000497
AC:
3
AN:
60368
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.458
Heterozygous variant carriers
0
1
3
4
6
7
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.0000330
Hom.:
0
Bravo
AF:
0.00000756

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:6
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Senior-Loken syndrome 5 Pathogenic:4
Feb 21, 2024
Fulgent Genetics, Fulgent Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Mar 04, 2024
Baylor Genetics
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 08, 2021
Ocular Genomics Institute, Massachusetts Eye and Ear
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:research

The IQCB1 c.1036G>T variant was identified in an individual with retinitis pigmentosa with a presumed recessive inheritance pattern. Through a review of available evidence we were able to apply the following criteria: PVS1, PM2, PM3, PP1-M, PS3. Based on this evidence we have classified this variant as Pathogenic. -

Jan 01, 2011
OMIM
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:literature only

- -

Nephronophthisis Pathogenic:1
Jul 30, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. ClinVar contains an entry for this variant (Variation ID: 30779). This premature translational stop signal has been observed in individuals with Leber congenital amaurosis (PMID: 21220633, 27624628). This variant is present in population databases (rs387907009, gnomAD 0.0009%). This sequence change creates a premature translational stop signal (p.Glu346*) 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). -

Leber congenital amaurosis Pathogenic:1
Jan 01, 2015
NIHR Bioresource Rare Diseases, University of Cambridge
Significance:Pathogenic
Review Status:no assertion criteria provided
Collection Method:research

- -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
BayesDel_addAF
Pathogenic
0.62
D
BayesDel_noAF
Pathogenic
0.57
CADD
Pathogenic
36
DANN
Uncertain
1.0
Eigen
Uncertain
0.63
Eigen_PC
Uncertain
0.41
FATHMM_MKL
Uncertain
0.90
D
PhyloP100
1.8
Vest4
0.22
GERP RS
2.3
RBP_binding_hub_radar
0.0
RBP_regulation_power_radar
1.1
Mutation Taster
=1/199
disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs387907009; hg19: chr3-121509013; COSMIC: COSV60438872; API