1-43442868-G-C

Variant names:

• chr1-43442868-G-C
• rs370164213
• NM_001365999.1:c.8201G>C

Variant summary

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

The NM_001365999.1(SZT2):​c.8201G>C​(p.Arg2734Pro) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000616 in 1,460,872 control chromosomes in the GnomAD database, with no homozygous occurrence. 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. R2734Q) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: SZT2 NM_001365999.1 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.89
• 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: 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

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SZT2	NM_001365999.1	c.8201G>C	p.Arg2734Pro	missense_variant	Exon 59 of 72	ENST00000634258.3	NP_001352928.1
SZT2	NM_015284.4	c.8030G>C	p.Arg2677Pro	missense_variant	Exon 58 of 71		NP_056099.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SZT2	ENST00000634258.3	c.8201G>C	p.Arg2734Pro	missense_variant	Exon 59 of 72	5	NM_001365999.1	ENSP00000489255.1
SZT2	ENST00000562955.2	c.8030G>C	p.Arg2677Pro	missense_variant	Exon 58 of 71	5		ENSP00000457168.1
SZT2	ENST00000648058.1	n.4655G>C		non_coding_transcript_exon_variant	Exon 27 of 40
SZT2	ENST00000649403.1	n.2951G>C		non_coding_transcript_exon_variant	Exon 24 of 37

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1460872 Hom.: 0 Cov.: 36 AF XY: 0.00000963 AC XY: 7 AN XY: 726692

African (AFR) AF: 0.00 AC: 0 AN: 33466

American (AMR) AF: 0.00 AC: 0 AN: 44616

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26052

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86072

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53358

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00000720 AC: 8 AN: 1111492

Other (OTH) AF: 0.0000166 AC: 1 AN: 60354

GnomAD4 genome Cov.: 32

EpiCase AF: 0.0000545

EpiControl AF: 0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Nov 22, 2018

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This variant is not present in population databases (ExAC no frequency). This sequence change replaces arginine with proline at codon 2677 of the SZT2 protein (p.Arg2677Pro). The arginine residue is highly conserved and there is a moderate physicochemical difference between arginine and proline. This variant has not been reported in the literature in individuals with SZT2-related conditions. 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. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be disruptive, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Pathogenic	29
DANN	Uncertain	0.98
DEOGEN2	Benign	0.21	T;.
Eigen	Pathogenic	0.75
Eigen_PC	Pathogenic	0.79
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.86	D;D
M_CAP	Benign	0.0072	T
MetaRNN	Uncertain	0.73	D;D
MetaSVM	Benign	-0.51	T
MutationAssessor	Benign	1.4	L;.
PhyloP100		9.9
PrimateAI	Uncertain	0.69	T
PROVEAN	Benign	-2.3	.;N
Sift	Benign	0.20	.;T
Sift4G	Pathogenic	0.0	D;D
Polyphen		1.0	.;D
Vest4		0.86
MutPred		0.27		.;Gain of sheet (P = 0.0101);
MVP		0.55
MPC		1.1
ClinPred		0.92	D
GERP RS		5.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.75
gMVP		0.75
Mutation Taster		=43/57	disease causing

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

Other links and lift over

dbSNP: rs370164213; hg19: chr1-43908539;