chr1-43430736-G-T

Variant names:

• chr1-43430736-G-T
• rs532357677
• NM_001365999.1:c.4721G>T

Variant summary

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

The NM_001365999.1(SZT2):​c.4721G>T​(p.Arg1574Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,548 control chromosomes in the GnomAD database, with no homozygous occurrence. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. 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: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: SZT2 NM_001365999.1 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 3.07
• 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 2 ACMG points.

• 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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SZT2	NM_001365999.1	MANE Select	c.4721G>T	p.Arg1574Leu	missense	Exon 32 of 72	NP_001352928.1
	SZT2	NM_015284.4		c.4550G>T	p.Arg1517Leu	missense	Exon 31 of 71	NP_056099.3

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SZT2	ENST00000634258.3	TSL:5 MANE Select	c.4721G>T	p.Arg1574Leu	missense	Exon 32 of 72	ENSP00000489255.1
	SZT2	ENST00000562955.2	TSL:5	c.4550G>T	p.Arg1517Leu	missense	Exon 31 of 71	ENSP00000457168.1
	SZT2	ENST00000478140.1	TSL:2	n.*39G>T		downstream_gene	N/A

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000401 AC: 1 AN: 249678 AF XY: 0.00000740

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.000164

GnomAD4 exome AF: 6.85e-7 AC: 1 AN: 1460548 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726602

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

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26128

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: 52122

Middle Eastern (MID) AF: 0.000173 AC: 1 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111980

Other (OTH) AF: 0.00 AC: 0 AN: 60390

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.37
BayesDel_addAF	Pathogenic	0.21	D
BayesDel_noAF	Uncertain	0.060
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.43	T
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.88	D
M_CAP	Benign	0.0069	T
MetaRNN	Uncertain	0.60	D
MetaSVM	Benign	-0.93	T
PhyloP100		3.1
PrimateAI	Benign	0.47	T
PROVEAN	Pathogenic	-4.7	D
Sift	Uncertain	0.0070	D
Sift4G	Uncertain	0.027	D
Polyphen		0.98	D
Vest4		0.60
MutPred		0.42		Loss of catalytic residue at R1517 (P = 0.0139)
MVP		0.42
MPC		0.98
ClinPred		0.97	D
GERP RS		5.8
Varity_R		0.16
gMVP		0.56
Mutation Taster		=80/20	polymorphism

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: rs532357677; hg19: chr1-43896407;