1-43430736-G-A

Position:

chr1-43430736-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 3P and 2B. PM2PP2BP4_Moderate

The NM_001365999.1(SZT2):c.4721G>A(p.Arg1574Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000291 in 1,612,880 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. R1574W) has been classified as Uncertain significance.

Frequency

Genomes: 𝑓 0.000053 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000027 ( 0 hom. )

Consequence

SZT2
NM_001365999.1 missense

Scores

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:5

Conservation

PhyloP100: 3.07

Variant links:

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 links:

SZT2 (HGNC:):

SZT2 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Uncertain_significance. Variant got 1 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

PP2

Missense variant in gene, where missense usually causes diseases (based on misZ statistic), SZT2. . Gene score misZ 2.5968 (greater than the threshold 3.09). Trascript score misZ 4.0086 (greater than threshold 3.09). GenCC has associacion of gene with undetermined early-onset epileptic encephalopathy, developmental and epileptic encephalopathy, 18, developmental and epileptic encephalopathy.

BP4

Computational evidence support a benign effect (MetaRNN=0.15724438).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SZT2	NM_001365999.1 linkuse as main transcript	c.4721G>A	p.Arg1574Gln	missense_variant	32/72	ENST00000634258.3	NP_001352928.1
SZT2	NM_015284.4 linkuse as main transcript	c.4550G>A	p.Arg1517Gln	missense_variant	31/71		NP_056099.3	Q5T011-5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	UniProt
SZT2	ENST00000634258.3 linkuse as main transcript	c.4721G>A	p.Arg1574Gln	missense_variant	32/72	5	NM_001365999.1	ENSP00000489255.1	Q5T011-1
SZT2	ENST00000562955.2 linkuse as main transcript	c.4550G>A	p.Arg1517Gln	missense_variant	31/71	5		ENSP00000457168.1	Q5T011-5
SZT2	ENST00000478140.1 linkuse as main transcript	n.*39G>A		downstream_gene_variant		2

Frequencies

GnomAD3 genomes

AF:

0.0000526

AC:

AN:

152218

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000482

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.000207

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000588

Gnomad OTH

AF:

0.000478

GnomAD3 exomes

AF:

0.0000200

AC:

AN:

249678

Hom.:

AF XY:

0.0000296

AC XY:

AN XY:

135058

show subpopulations

Gnomad AFR exome

AF:

0.0000618

Gnomad AMR exome

AF:

0.00

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.000131

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.0000267

AC:

AN:

1460544

Hom.:

Cov.:

AF XY:

0.0000317

AC XY:

AN XY:

726602

show subpopulations

Gnomad4 AFR exome

AF:

0.0000299

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.0000383

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.000220

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000144

Gnomad4 OTH exome

AF:

0.0000331

GnomAD4 genome

AF:

0.0000525

AC:

AN:

152336

Hom.:

Cov.:

AF XY:

0.0000537

AC XY:

AN XY:

74486

show subpopulations

Gnomad4 AFR

AF:

0.0000481

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.000207

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000588

Gnomad4 OTH

AF:

0.000473

Alfa

AF:

0.000161

Hom.:

Bravo

AF:

0.0000189

ExAC

AF:

0.0000330

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:5

Revision: criteria provided, multiple submitters, no conflicts

LINK: link

Submissions by phenotype

Developmental and epileptic encephalopathy, 18

Uncertain:3

Uncertain significance, criteria provided, single submitter	clinical testing	Neuberg Centre For Genomic Medicine, NCGM	-	The observed missense variant c.4721G>A(p.Arg1574Gln) in SZT2 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. The c.4721G>A variant has 0.004% allele frequency in gnomAD Exomes.This variant has been reported to the ClinVar database as Uncertain Significance. However, study on multiple affected individuals and the functional impact of the variant is not available.The amino acid Arginine at position 1574 is changed to a Glutamine changing protein sequence and it might alter its composition and physico-chemical properties. The amino acid change p.Arg1574Gln in SZT2 is predicted as conserved by GERP++ and PhyloP across 100 vertebrates. For these reasons, this variant has been classified as Uncertain Significance. -
Uncertain significance, criteria provided, single submitter	clinical testing	Genome-Nilou Lab	Apr 11, 2023	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Institute of Human Genetics, University of Leipzig Medical Center	Dec 08, 2022	This variant was identified together with NM_015284.4:c.8640del in the same patient. Criteria applied: PM2_SUP, PM5_SUP -

Inborn genetic diseases

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 13, 2022

The c.4550G>A (p.R1517Q) alteration is located in exon 31 (coding exon 31) of the SZT2 gene. This alteration results from a G to A substitution at nucleotide position 4550, causing the arginine (R) at amino acid position 1517 to be replaced by a glutamine (Q). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

not provided

Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

May 24, 2022

This sequence change replaces arginine, which is basic and polar, with glutamine, which is neutral and polar, at codon 1517 of the SZT2 protein (p.Arg1517Gln). This variant is present in population databases (rs532357677, gnomAD 0.01%). This variant has not been reported in the literature in individuals affected with SZT2-related conditions. ClinVar contains an entry for this variant (Variation ID: 411940). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Possibly Damaging"; Align-GVGD: "Class C0". The glutamine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may create or strengthen a splice site. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

AlphaMissense

Benign

0.14

BayesDel_addAF

Benign

-0.16

BayesDel_noAF

Benign

-0.16

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Benign

0.20

T;.

Eigen

Uncertain

0.45

Eigen_PC

Uncertain

0.50

FATHMM_MKL

Uncertain

0.83

LIST_S2

Uncertain

0.90

D;D

M_CAP

Benign

0.0079

MetaRNN

Benign

0.16

T;T

MetaSVM

Benign

-0.93

PrimateAI

Benign

0.41

PROVEAN

Benign

-1.8

.;N

Sift

Uncertain

0.018

.;D

Sift4G

Benign

0.073

T;T

Polyphen

0.98

.;D

Vest4

0.21

MutPred

0.37

.;Loss of methylation at R1517 (P = 0.0463);

MVP

0.47

MPC

0.89

ClinPred

0.95

GERP RS

5.8

Varity_R

0.055

gMVP

0.40

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.070

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over