1-43425140-G-T

Variant names:

• chr1-43425140-G-T
• rs143992266
• NM_001365999.1:c.2578G>T
• SZT2 p.Glu860*

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_001365999.1(SZT2):​c.2578G>T​(p.Glu860*) variant causes a stop gained change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,868 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SZT2 NM_001365999.1 stop_gained
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.93
• Publications: 0 publications found

Genes affected

SZT2 (HGNC:29040): (SZT2 subunit of KICSTOR complex) The protein encoded by this gene is expressed in the brain, predominantly in the parietal and frontal cortex as well as in dorsal root ganglia. It is localized to the peroxisome, and is implicated in resistance to oxidative stress. It likely functions by increasing superoxide dismutase (SOD) activity, but itself has no direct SOD activity. Studies in mice show that this gene confers low seizure threshold, and may also enhance epileptogenesis. [provided by RefSeq, Jun 2011]

SZT2 Gene-Disease associations (from GenCC):

• developmental and epileptic encephalopathy, 18

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Illumina, Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, PanelApp Australia
• genetic developmental and epileptic encephalopathy

  Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
• undetermined early-onset epileptic encephalopathy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001365999.1. 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
	SZT2	NM_001365999.1	MANE Select	c.2578G>T	p.Glu860*	stop_gained	Exon 18 of 72	NP_001352928.1	Q5T011-1
	SZT2	NM_015284.4		c.2578G>T	p.Glu860*	stop_gained	Exon 18 of 71	NP_056099.3	Q5T011-5

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SZT2	ENST00000634258.3	TSL:5 MANE Select	c.2578G>T	p.Glu860*	stop_gained	Exon 18 of 72	ENSP00000489255.1	Q5T011-1
	SZT2	ENST00000562955.2	TSL:5	c.2578G>T	p.Glu860*	stop_gained	Exon 18 of 71	ENSP00000457168.1	Q5T011-5
	SZT2	ENST00000470139.1	TSL:2	n.1309G>T		non_coding_transcript_exon	Exon 9 of 18	ENSP00000492726.1	A0A1W2PRY5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461868 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44718

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112000

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.29
CADD	Pathogenic	35
DANN	Uncertain	0.99
Eigen	Uncertain	0.47
Eigen_PC	Benign	0.20
FATHMM_MKL	Benign	0.48	N
PhyloP100		1.9
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=10/190	disease causing (fs/PTC)

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs143992266;

hg19: chr1-43890811;