rs387907302

Variant names:

• chr9-2717965-C-T
• rs387907302
• NM_133497.4:c.226C>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_133497.4(KCNV2):​c.226C>T​(p.Gln76*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,882 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: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: KCNV2 NM_133497.4 stop_gained
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 1.00
• Publications: 3 publications found

Genes affected

KCNV2 (HGNC:19698): (potassium voltage-gated channel modifier subfamily V member 2) Voltage-gated potassium (Kv) channels represent the most complex class of voltage-gated ion channels from both functional and structural standpoints. Their diverse functions include regulating neurotransmitter release, heart rate, insulin secretion, neuronal excitability, epithelial electrolyte transport, smooth muscle contraction, and cell volume. This gene encodes a member of the potassium voltage-gated channel subfamily V. This member is identified as a 'silent subunit', and it does not form homomultimers, but forms heteromultimers with several other subfamily members. Through obligatory heteromerization, it exerts a function-altering effect on other potassium channel subunits. This protein is strongly expressed in pancreas and has a weaker expression in several other tissues. [provided by RefSeq, Jul 2008]

KCNV2 Gene-Disease associations (from GenCC):

• cone dystrophy with supernormal rod response

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• inherited retinal dystrophy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen

ENSG00000286670 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 12 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 9-2717965-C-T is Pathogenic according to our data. Variant chr9-2717965-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 37249.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCNV2	NM_133497.4	c.226C>T	p.Gln76*	stop_gained	Exon 1 of 2	ENST00000382082.4	NP_598004.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCNV2	ENST00000382082.4	c.226C>T	p.Gln76*	stop_gained	Exon 1 of 2	1	NM_133497.4	ENSP00000371514.3
ENSG00000286670	ENST00000768783.1	n.113+28333G>A		intron_variant	Intron 1 of 3
ENSG00000286670	ENST00000768784.1	n.156+13980G>A		intron_variant	Intron 1 of 3
ENSG00000286670	ENST00000768785.1	n.156+13980G>A		intron_variant	Intron 1 of 2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461882 Hom.: 0 Cov.: 81 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1112008

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 33

Alfa AF: 0.00 Hom.: 0

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Pathogenic:1

Oct 03, 2023

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.Gln76*) in the KCNV2 gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in KCNV2 are known to be pathogenic (PMID: 16909397, 18235024). This variant is not present in population databases (gnomAD no frequency). This premature translational stop signal has been observed in individual(s) with KCNV2-related conditions (PMID: 18235024). ClinVar contains an entry for this variant (Variation ID: 37249). For these reasons, this variant has been classified as Pathogenic. -

Cone dystrophy with supernormal rod response Pathogenic:1

Feb 01, 2008

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.64	D
BayesDel_noAF	Uncertain	-0.060
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Benign	-0.064
Eigen_PC	Benign	-0.43
FATHMM_MKL	Benign	0.11	N
PhyloP100		1.0
Vest4		0.67
GERP RS		0.64
PromoterAI		-0.0054	Neutral
Mutation Taster		=3/197	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

Other links and lift over

dbSNP: rs387907302; hg19: chr9-2717965;