rs193920929

Variant names:

• chr1-154771974-C-A
• rs193920929
• NM_002249.6:c.1448+1G>T

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_002249.6(KCNN3):​c.1448+1G>T variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (no stars).

• Frequency: Genomes: not found (cov: 32)
• Consequence: KCNN3 NM_002249.6 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 7.86
• Publications: 0 publications found

Genes affected

KCNN3 (HGNC:6292): (potassium calcium-activated channel subfamily N member 3) Action potentials in vertebrate neurons are followed by an afterhyperpolarization (AHP) that may persist for several seconds and may have profound consequences for the firing pattern of the neuron. Each component of the AHP is kinetically distinct and is mediated by different calcium-activated potassium channels. This gene belongs to the KCNN family of potassium channels. It encodes an integral membrane protein that forms a voltage-independent calcium-activated channel, which is thought to regulate neuronal excitability by contributing to the slow component of synaptic AHP. This gene contains two CAG repeat regions in the coding sequence. It was thought that expansion of one or both of these repeats could lead to an increased susceptibility to schizophrenia or bipolar disorder, but studies indicate that this is probably not the case. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Feb 2011]

KCNN3 Gene-Disease associations (from GenCC):

• Zimmermann-Laband syndrome 3

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• Zimmermann-Laband syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• schizophrenia

  Inheritance: Unknown Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

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

• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_002249.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNN3	NM_002249.6	MANE Select	c.1448+1G>T		splice_donor intron	N/A	NP_002240.3
	KCNN3	NM_001204087.2		c.1448+1G>T		splice_donor intron	N/A	NP_001191016.1
	KCNN3	NM_001365837.1		c.509+1G>T		splice_donor intron	N/A	NP_001352766.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	KCNN3	ENST00000271915.9	TSL:1 MANE Select	c.1448+1G>T		splice_donor intron	N/A	ENSP00000271915.3
	KCNN3	ENST00000361147.8	TSL:1	c.533+1G>T		splice_donor intron	N/A	ENSP00000354764.4
	KCNN3	ENST00000358505.2	TSL:1	c.509+1G>T		splice_donor intron	N/A	ENSP00000351295.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions as Germline

Significance: Uncertain significance

Revision: no assertion criteria provided

Pathogenic	VUS	Benign	Condition
-	1	-	Prostate cancer (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.34	D
BayesDel_noAF	Pathogenic	0.24
CADD	Pathogenic	33
DANN	Uncertain	0.99
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Pathogenic	1.0	D
PhyloP100		7.9
GERP RS		4.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs193920929; hg19: chr1-154744450;