chr1-111777036-G-A

Variant names:

• chr1-111777036-G-A
• rs778053688
• NM_001378969.1:c.1756C>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 3P and 1B. PM2 PP2 BP4

The NM_001378969.1(KCND3):​c.1756C>T​(p.Leu586Phe) variant causes a missense change. The variant allele was found at a frequency of 0.00000205 in 1,461,168 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 Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. L586V) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: KCND3 NM_001378969.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.46
• Publications: 0 publications found

Genes affected

KCND3 (HGNC:6239): (potassium voltage-gated channel subfamily D member 3) 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 includes two isoforms with different sizes, which are encoded by alternatively spliced transcript variants of this gene. [provided by RefSeq, Jul 2008]

KCND3 Gene-Disease associations (from GenCC):

• neurodevelopmental disorder

  Inheritance: AD Classification: STRONG Submitted by: G2P
• spinocerebellar ataxia type 19/22

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet
• Brugada syndrome 9

  Inheritance: AD Classification: LIMITED Submitted by: Genomics England PanelApp
• Brugada syndrome 1

  Inheritance: AD Classification: NO_KNOWN Submitted by: ClinGen

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the KCND3 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 20 curated pathogenic missense variants (we use a threshold of 10). The gene has 4 curated benign missense variants. Gene score misZ: 3.8545 (above the threshold of 3.09). Trascript score misZ: 4.8782 (above the threshold of 3.09). GenCC associations: The gene is linked to spinocerebellar ataxia type 19/22, neurodevelopmental disorder, Brugada syndrome 1, Brugada syndrome 9.
• BP4: Computational evidence support a benign effect (MetaRNN=0.31240898).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001378969.1. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCND3	NM_001378969.1	MANE Select	c.1756C>T	p.Leu586Phe	missense	Exon 7 of 8	NP_001365898.1	Q9UK17-1
	KCND3	NM_004980.5		c.1756C>T	p.Leu586Phe	missense	Exon 7 of 8	NP_004971.2
	KCND3	NM_001378970.1		c.1699C>T	p.Leu567Phe	missense	Exon 6 of 7	NP_001365899.1	Q9UK17-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCND3	ENST00000302127.5	TSL:5 MANE Select	c.1756C>T	p.Leu586Phe	missense	Exon 7 of 8	ENSP00000306923.4	Q9UK17-1
	KCND3	ENST00000315987.6	TSL:1	c.1756C>T	p.Leu586Phe	missense	Exon 7 of 8	ENSP00000319591.2	Q9UK17-1
	KCND3	ENST00000369697.5	TSL:1	c.1699C>T	p.Leu567Phe	missense	Exon 5 of 6	ENSP00000358711.1	Q9UK17-2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251076 AF XY: 0.00000737

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: 0.0000462

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461168 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726892

African (AFR) AF: 0.00 AC: 0 AN: 33456

American (AMR) AF: 0.00 AC: 0 AN: 44712

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86212

European-Finnish (FIN) AF: 0.0000562 AC: 3 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5374

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111842

Other (OTH) AF: 0.00 AC: 0 AN: 60324

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	Cardiovascular phenotype (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.060
BayesDel_addAF	Uncertain	0.11	D
BayesDel_noAF	Uncertain	-0.070
CADD	Benign	23
DANN	Uncertain	0.99
DEOGEN2	Benign	0.36	T
Eigen	Uncertain	0.32
Eigen_PC	Uncertain	0.45
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Benign	0.81	T
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.31	T
MetaSVM	Uncertain	0.41	D
PhyloP100		6.5
PrimateAI	Uncertain	0.75	T
PROVEAN	Benign	-0.77	N
REVEL	Uncertain	0.49
Sift	Benign	0.21	T
Sift4G	Benign	0.34	T
Polyphen		0.83	P
Vest4		0.45
MutPred		0.11		Loss of glycosylation at T588 (P = 0.0787)
MVP		0.55
MPC		0.74
ClinPred		0.99	D
GERP RS		5.4
Varity_R		0.11
gMVP		0.31
Mutation Taster		=64/36	polymorphism

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: rs778053688; hg19: chr1-112319658;