chr3-121781790-G-C

Position:

• chr3-121781790-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001023570.4(IQCB1):​c.1363C>G​(p.Arg455Gly) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 31)
• Consequence: IQCB1 NM_001023570.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 2.50

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 Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.819

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IQCB1	NM_001023570.4	c.1363C>G	p.Arg455Gly	missense_variant	13/15	ENST00000310864.11	NP_001018864.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IQCB1	ENST00000310864.11	c.1363C>G	p.Arg455Gly	missense_variant	13/15	1	NM_001023570.4	ENSP00000311505.6
IQCB1	ENST00000349820.10	c.964C>G	p.Arg322Gly	missense_variant	10/12	1		ENSP00000323756.7
IQCB1	ENST00000393650.7	n.*341C>G		non_coding_transcript_exon_variant	12/14	5		ENSP00000377261.3
IQCB1	ENST00000393650.7	n.*341C>G		3_prime_UTR_variant	12/14	5		ENSP00000377261.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 31

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.47
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.29
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.40	T;.
Eigen	Benign	0.17
Eigen_PC	Benign	0.090
FATHMM_MKL	Benign	0.67	D
LIST_S2	Benign	0.82	T;T
M_CAP	Uncertain	0.12	D
MetaRNN	Pathogenic	0.82	D;D
MetaSVM	Uncertain	-0.041	T
MutationAssessor	Uncertain	2.7	M;.
PrimateAI	Benign	0.41	T
PROVEAN	Pathogenic	-4.5	D;D
REVEL	Pathogenic	0.69
Sift	Pathogenic	0.0	D;D
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.99	D;D
Vest4		0.70
MutPred		0.55		Gain of loop (P = 0.002);.;
MVP		0.91
MPC		0.51
ClinPred		1.0	D
GERP RS		2.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.76
gMVP		0.76

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: rs866982675; hg19: chr3-121500637;