chr9-135702258-C-A

Position:

• chr9-135702258-C-A

Variant summary

Our verdict is Benign. Variant got -20 ACMG points: 0P and 20B. BP4_Strong BP6_Very_Strong BS1 BS2

The NM_020822.3(KCNT1):​c.-1C>A variant causes a 5 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000654 in 1,606,658 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 Benign (★★).

• Frequency:
  • Genomes: 𝑓 0.00035 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000035 (0 hom.)
• Consequence: KCNT1 NM_020822.3 5_prime_UTR
• Clinical Significance: Benign criteria provided, multiple submitters, no conflicts B:4
• Conservation: PhyloP100: 0.116

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]

SOHLH1 (HGNC:):

ACMG classification

Verdict is Benign. Variant got -20 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.56).
• BP6: Variant 9-135702258-C-A is Benign according to our data. Variant chr9-135702258-C-A is described in ClinVar as [Benign]. Clinvar id is 388332.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• BS1: Variant frequency is greater than expected in population afr. gnomad4 allele frequency = 0.000355 (54/152174) while in subpopulation AFR AF= 0.00128 (53/41530). AF 95% confidence interval is 0.001. There are 0 homozygotes in gnomad4. There are 30 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High AC in GnomAd4 at 54 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
KCNT1	NM_020822.3	c.-1C>A		5_prime_UTR_variant	1/31	ENST00000371757.7	NP_065873.2
KCNT1	NM_001272003.2	c.-1C>A		5_prime_UTR_variant	1/31		NP_001258932.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
KCNT1	ENST00000371757	c.-1C>A		5_prime_UTR_variant	1/31	1	NM_020822.3	ENSP00000360822.2

Frequencies

GnomAD3 genomes AF: 0.000355 AC: 54 AN: 152054 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00128

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.000110 AC: 26 AN: 235976 Hom.: 0 AF XY: 0.0000843 AC XY: 11 AN XY: 130504

Gnomad AFR exome AF: 0.00184

Gnomad AMR exome AF: 0.0000294

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000351 AC: 51 AN: 1454484 Hom.: 0 Cov.: 31 AF XY: 0.0000249 AC XY: 18 AN XY: 723550

Gnomad4 AFR exome AF: 0.00148

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000333

GnomAD4 genome AF: 0.000355 AC: 54 AN: 152174 Hom.: 0 Cov.: 33 AF XY: 0.000403 AC XY: 30 AN XY: 74396

Gnomad4 AFR AF: 0.00128

Gnomad4 AMR AF: 0.0000654

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000427 Hom.: 0

Bravo AF: 0.000480

ClinVar

Significance: Benign

Submissions summary: Benign:4

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Benign:1

Benign, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 11, 2018

This alteration is classified as benign based on a combination of the following: seen in unaffected individuals, population frequency, intact protein function, lack of segregation with disease, co-occurrence, RNA analysis, in silico models, amino acid conservation, lack of disease association in case-control studies, and/or the mechanism of disease or impacted region is inconsistent with a known cause of pathogenicity. -

Developmental and epileptic encephalopathy, 14 Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Mar 15, 2022

- -

not provided Benign:1

Benign, criteria provided, single submitter

clinical testing

GeneDx

Oct 26, 2018

- -

Autosomal dominant nocturnal frontal lobe epilepsy 5 Benign:1

Benign, criteria provided, single submitter

clinical testing

Genome-Nilou Lab

Mar 15, 2022

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.56
CADD	Benign	7.0
DANN	Benign	0.86

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: rs149383208; hg19: chr9-138594104;