dbSNP rs1554421107: KCND2:p.Phe326Phe (chr7-120275610-C-T) – ACMG Classification: Likely_benign (-5 pts)

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2BP4_StrongBP6_ModerateBP7

The NM_012281.3(KCND2):c.978C>T(p.Phe326Phe) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,002 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 Likely benign (★).

Frequency

Genomes: not found (cov: 31)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

KCND2
NM_012281.3 synonymous

Scores

Clinical Significance

Likely benign criteria provided, single submitter B:1

Conservation

PhyloP100: 1.69

Publications

0 publications found

Variant links:

Genes affected

KCND2 (HGNC:6238): (potassium voltage-gated channel subfamily D 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. Four sequence-related potassium channel genes - shaker, shaw, shab, and shal - have been identified in Drosophila, and each has been shown to have human homolog(s). This gene encodes a member of the potassium channel, voltage-gated, shal-related subfamily, members of which form voltage-activated A-type potassium ion channels and are prominent in the repolarization phase of the action potential. This member mediates a rapidly inactivating, A-type outward potassium current which is not under the control of the N terminus as it is in Shaker channels. [provided by RefSeq, Jul 2008]

KCND2 Gene-Disease associations (from GenCC):

KCND2-related neurodevelopmental disorder with or without seizures
Inheritance: AD Classification: MODERATE Submitted by: G2P
complex neurodevelopmental disorder
Inheritance: AD Classification: LIMITED Submitted by: Illumina

KCND2 links:

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -5 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.51).

BP6

Variant 7-120275610-C-T is Benign according to our data. Variant chr7-120275610-C-T is described in ClinVar as Likely_benign. ClinVar VariationId is 460208.Status of the report is criteria_provided_single_submitter, 1 stars.

BP7

Synonymous conserved (PhyloP=1.69 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
KCND2	NM_012281.3 link	c.978C>T	p.Phe326Phe	synonymous_variant	Exon 1 of 6	ENST00000331113.9	NP_036413.1	Q9NZV8A4D0V9
KCND2	XM_047420346.1 link	c.978C>T	p.Phe326Phe	synonymous_variant	Exon 2 of 7		XP_047276302.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
KCND2	ENST00000331113.9 link	c.978C>T	p.Phe326Phe	synonymous_variant	Exon 1 of 6	1	NM_012281.3	ENSP00000333496.4		Q9NZV8

Frequencies

GnomAD3 genomes

Cov.:

GnomAD4 exome

AF:

6.85e-7

AC:

AN:

1460002

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

726350

show subpopulations

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR)

AF:

0.00

AC:

AN:

33480

American (AMR)

AF:

0.0000224

AC:

AN:

44724

Ashkenazi Jewish (ASJ)

AF:

0.00

AC:

AN:

26136

East Asian (EAS)

AF:

0.00

AC:

AN:

39700

South Asian (SAS)

AF:

0.00

AC:

AN:

86252

European-Finnish (FIN)

AF:

0.00

AC:

AN:

51570

Middle Eastern (MID)

AF:

0.00

AC:

AN:

5768

European-Non Finnish (NFE)

AF:

0.00

AC:

AN:

1111992

Other (OTH)

AF:

0.00

AC:

AN:

60380

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Allele Balance Distribution

Red line indicates average allele balance

Average allele balance: 0.375

Heterozygous variant carriers

0.00

0.20

0.40

0.60

0.80

0.95

Allele balance

GnomAD4 genome

Cov.:

Alfa

AF:

0.00

Hom.:

Bravo

AF:

0.0000113

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Early myoclonic encephalopathy

Benign:1

Jan 20, 2025

Labcorp Genetics (formerly Invitae), Labcorp

Significance:Likely benign

Review Status:criteria provided, single submitter

Collection Method:clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_noAF

Benign

-0.51

CADD

Benign

(source)

DANN

Benign

0.76

PhyloP100

1.7

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

You must be logged in to view publications. This limit was set because tens of millions (!) of queries from AI bots are generated daily.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

Publications

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

Other links and lift over