rs775153972

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 0P and 2B. BP4_Moderate

The NM_001365999.1(SZT2):​c.4343G>A​(p.Arg1448His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000372 in 1,613,936 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict 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. R1448C) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000026 ( 0 hom., cov: 32)
Exomes 𝑓: 0.000038 ( 0 hom. )

Consequence

SZT2
NM_001365999.1 missense

Scores

5
13

Clinical Significance

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

Conservation

PhyloP100: 2.26

Publications

0 publications found
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 Gene-Disease associations (from GenCC):
  • developmental and epileptic encephalopathy, 18
    Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), G2P, Illumina
  • genetic developmental and epileptic encephalopathy
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • undetermined early-onset epileptic encephalopathy
    Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_benign. The variant received -2 ACMG points.

BP4
Computational evidence support a benign effect (MetaRNN=0.113082886).

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
SZT2NM_001365999.1 linkc.4343G>A p.Arg1448His missense_variant Exon 30 of 72 ENST00000634258.3 NP_001352928.1
SZT2NM_015284.4 linkc.4172G>A p.Arg1391His missense_variant Exon 29 of 71 NP_056099.3 Q5T011-5

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
SZT2ENST00000634258.3 linkc.4343G>A p.Arg1448His missense_variant Exon 30 of 72 5 NM_001365999.1 ENSP00000489255.1 Q5T011-1
SZT2ENST00000562955.2 linkc.4172G>A p.Arg1391His missense_variant Exon 29 of 71 5 ENSP00000457168.1 Q5T011-5
SZT2ENST00000478140.1 linkn.204G>A non_coding_transcript_exon_variant Exon 1 of 3 2

Frequencies

GnomAD3 genomes
AF:
0.0000263
AC:
4
AN:
152048
Hom.:
0
Cov.:
32
show subpopulations
Gnomad AFR
AF:
0.00
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.000288
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.0000441
Gnomad OTH
AF:
0.00
GnomAD2 exomes
AF:
0.0000477
AC:
12
AN:
251492
AF XY:
0.0000662
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.000595
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.0000264
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.0000383
AC:
56
AN:
1461888
Hom.:
0
Cov.:
32
AF XY:
0.0000495
AC XY:
36
AN XY:
727246
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.000650
AC:
17
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39700
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53416
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5766
European-Non Finnish (NFE)
AF:
0.0000279
AC:
31
AN:
1112012
Other (OTH)
AF:
0.0000828
AC:
5
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.479
Heterozygous variant carriers
0
4
8
11
15
19
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
AF:
0.0000263
AC:
4
AN:
152048
Hom.:
0
Cov.:
32
AF XY:
0.0000404
AC XY:
3
AN XY:
74274
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
41372
American (AMR)
AF:
0.00
AC:
0
AN:
15276
Ashkenazi Jewish (ASJ)
AF:
0.000288
AC:
1
AN:
3470
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5188
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4824
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10602
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
316
European-Non Finnish (NFE)
AF:
0.0000441
AC:
3
AN:
68004
Other (OTH)
AF:
0.00
AC:
0
AN:
2088
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.500
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Genome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
Alfa
AF:
0.0000579
Hom.:
0
Bravo
AF:
0.0000302
TwinsUK
AF:
0.000270
AC:
1
ALSPAC
AF:
0.00
AC:
0
ExAC
AF:
0.0000247
AC:
3
Asia WGS
AF:
0.000289
AC:
1
AN:
3478
EpiCase
AF:
0.0000545
EpiControl
AF:
0.000119

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:2
Aug 07, 2018
Genomic Research Center, Shahid Beheshti University of Medical Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Apr 11, 2023
Genome-Nilou Lab
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Developmental and epileptic encephalopathy, 1 Uncertain:1
Aug 07, 2018
Genomic Research Center, Shahid Beheshti University of Medical Sciences
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

- -

Inborn genetic diseases Uncertain:1
Feb 03, 2017
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.R1391H variant (also known as c.4172G>A), located in coding exon 29 of the SZT2 gene, results from a G to A substitution at nucleotide position 4172. The arginine at codon 1391 is replaced by histidine, an amino acid with highly similar properties. This amino acid position is poorly conserved in available vertebrate species. In addition, this alteration is predicted to be tolerated by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear. -

not provided Uncertain:1
Nov 13, 2021
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 1391 of the SZT2 protein (p.Arg1391His). This variant is present in population databases (rs775153972, gnomAD 0.06%). 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: 587458). Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The histidine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. 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
0.091
BayesDel_addAF
Benign
-0.29
T
BayesDel_noAF
Benign
-0.48
CADD
Benign
22
DANN
Uncertain
0.99
DEOGEN2
Benign
0.41
T;.
Eigen
Benign
-0.42
Eigen_PC
Benign
-0.26
FATHMM_MKL
Uncertain
0.79
D
LIST_S2
Benign
0.74
T;T
M_CAP
Benign
0.0065
T
MetaRNN
Benign
0.11
T;T
MetaSVM
Benign
-1.0
T
MutationAssessor
Benign
1.1
L;.
PhyloP100
2.3
PrimateAI
Benign
0.41
T
PROVEAN
Uncertain
-3.0
.;D
Sift
Uncertain
0.026
.;D
Sift4G
Uncertain
0.0060
D;D
Polyphen
0.0080
.;B
Vest4
0.33
MutPred
0.36
.;Loss of helix (P = 0.0626);
MVP
0.33
MPC
0.33
ClinPred
0.093
T
GERP RS
2.8
Varity_R
0.039
gMVP
0.39
Mutation Taster
=85/15
polymorphism

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
Details are displayed if max score is > 0.2

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

Publications

Other links and lift over

dbSNP: rs775153972; hg19: chr1-43895716; COSMIC: COSV65170342; COSMIC: COSV65170342; API