rs773621687

chr9-135770886-G-A

Variant summary

Our verdict is Benign. Variant got -7 ACMG points: 0P and 7B. BP4_Moderate BP6 BS2

The NM_020822.3(KCNT1):c.1799G>A(p.Arg600Gln) variant causes a missense change. The variant allele was found at a frequency of 0.0000251 in 1,592,210 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000026 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000025 (1 hom.)
• Consequence: KCNT1 NM_020822.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 5.47

Genes affected

KCNT1 (HGNC:18865): (potassium sodium-activated channel subfamily T member 1) Potassium 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 sodium-activated potassium channel subunit which is thought to function in ion conductance and developmental signaling pathways. Mutations in this gene cause the early-onset epileptic disorders, malignant migrating partial seizures of infancy and autosomal dominant nocturnal frontal lobe epilepsy. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Dec 2012]

ACMG classification

Verdict is Benign. Variant got -7 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.2458139).
• BP6: Variant 9-135770886-G-A is Benign according to our data. Variant chr9-135770886-G-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 375542.We mark this variant Likely_benign, oryginal submissions are: {Likely_benign=1, Uncertain_significance=1}.
• BS2: High AC in GnomAd at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
KCNT1	NM_020822.3	c.1799G>A	p.Arg600Gln	missense_variant	18/31	ENST00000371757.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
KCNT1	ENST00000371757.7	c.1799G>A	p.Arg600Gln	missense_variant	18/31	1	NM_020822.3	A2

Frequencies

GnomAD3 genomes AF: 0.0000329 AC: 5 AN: 152180 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.000621

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00633

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000425 AC: 9 AN: 211992 Hom.: 0 AF XY: 0.0000524 AC XY: 6 AN XY: 114588

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000325

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.000183

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000326

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000250 AC: 36 AN: 1439912 Hom.: 1 Cov.: 33 AF XY: 0.0000364 AC XY: 26 AN XY: 714392

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.0000242

Gnomad4 ASJ exome AF: 0.0000390

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.000275

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000818

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000263 AC: 4 AN: 152298 Hom.: 0 Cov.: 33 AF XY: 0.0000537 AC XY: 4 AN XY: 74470

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.000621

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.0000434 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.0000413 AC: 5

Asia WGS AF: 0.000289 AC: 1 AN: 3478

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Uncertain:1 Benign:1

Revision: criteria provided, conflicting classifications

Submissions by phenotype

Epileptic encephalopathy Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neurogenetics Laboratory - MEYER, AOU Meyer

Nov 16, 2016

- -

Developmental and epileptic encephalopathy, 14;C3554306:Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Invitae

Jul 30, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.088
BayesDel_addAF	Benign	-0.078	T
BayesDel_noAF	Uncertain	-0.060
Cadd	Uncertain	25
Dann	Uncertain	1.0
Eigen	Uncertain	0.23
Eigen_PC	Benign	0.21
FATHMM_MKL	Uncertain	0.97	D
LIST_S2	Uncertain	0.97	D;D;D;D;D;D;D;D;D;D
M_CAP	Uncertain	0.11	D
MetaRNN	Benign	0.25	T;T;T;T;T;T;T;T;T;T
MetaSVM	Benign	-1.0	T
MutationTaster	Benign	1.0	D;D;D;D;D;D;D;D
PrimateAI	Uncertain	0.60	T
REVEL	Benign	0.18
Sift4G	Benign	0.20	T;T;T;T;T;T;T;T;T;T
Polyphen		0.68	.;.;.;.;.;.;.;.;P;.
Vest4		0.44
MutPred		0.49		.;.;.;.;.;.;Gain of ubiquitination at K580 (P = 0.0556);Gain of ubiquitination at K580 (P = 0.0556);Gain of ubiquitination at K580 (P = 0.0556);Gain of ubiquitination at K580 (P = 0.0556);
MVP		0.57
MPC		0.79
ClinPred		0.62	D
GERP RS		4.0
Varity_R		0.31
gMVP		0.76

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs773621687; hg19: chr9-138662732;