9-132329295-T-A

Position:

• chr9-132329295-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_015046.7(SETX):​c.2303A>T​(p.Lys768Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,514 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: SETX NM_015046.7 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:2
• Conservation: PhyloP100: 2.48

Genes affected

SETX (HGNC:445): (senataxin) This gene encodes a protein named for its homology to the Sen1p protein of fungi which has RNA helicase activity encoded by a domain at the C-terminal end of the protein. The protein encoded by this gene contains a DNA/RNA helicase domain at its C-terminal end which suggests that it may be involved in both DNA and RNA processing. Mutations in this gene have been associated with ataxia-ocular apraxia-2 (AOA2) and an autosomal dominant form of juvenile amyotrophic lateral sclerosis (ALS4). [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.28409535).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SETX	NM_015046.7	c.2303A>T	p.Lys768Met	missense_variant	10/26	ENST00000224140.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SETX	ENST00000224140.6	c.2303A>T	p.Lys768Met	missense_variant	10/26	1	NM_015046.7	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461514 Hom.: 0 Cov.: 36 AF XY: 0.00000550 AC XY: 4 AN XY: 727028

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000360

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, single submitter

Submissions by phenotype

Spinocerebellar ataxia, autosomal recessive, with axonal neuropathy 2;C1865409:Amyotrophic lateral sclerosis type 4 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 27, 2021

This sequence change replaces lysine, a(n) basic and polar amino acid, with methionine, a(n) neutral and non-polar amino acid, at codon 768 of the SETX protein (p.Lys768Met). 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. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SETX protein function. ClinVar contains an entry for this variant (Variation ID: 468492). This variant has not been reported in the literature in individuals affected with SETX-related conditions. This variant is not present in population databases (gnomAD no frequency). -

SETX-related disorder Uncertain:1

Uncertain significance, no assertion criteria provided

clinical testing

PreventionGenetics, part of Exact Sciences

Oct 30, 2023

The SETX c.2303A>T variant is predicted to result in the amino acid substitution p.Lys768Met. To our knowledge, this variant has not been reported in the literature or in a large population database (http://gnomad.broadinstitute.org), indicating this variant is rare. At this time, the clinical significance of this variant is uncertain due to the absence of conclusive functional and genetic evidence. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.18
BayesDel_addAF	Uncertain	0.094	D
BayesDel_noAF	Benign	-0.10
CADD	Benign	22
DANN	Uncertain	0.99
DEOGEN2	Benign	0.16	T
Eigen	Benign	0.10
Eigen_PC	Benign	0.037
FATHMM_MKL	Uncertain	0.96	D
LIST_S2	Benign	0.73	T
M_CAP	Benign	0.041	D
MetaRNN	Benign	0.28	T
MetaSVM	Benign	-0.29	T
MutationAssessor	Uncertain	2.0	M
MutationTaster	Benign	0.77	N;N;N
PrimateAI	Benign	0.38	T
PROVEAN	Benign	-1.5	N
REVEL	Uncertain	0.32
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.011	D
Polyphen		0.99	D
Vest4		0.40
MutPred		0.17		Loss of ubiquitination at K768 (P = 6e-04);
MVP		0.75
MPC		0.46
ClinPred		0.91	D
GERP RS		3.1
Varity_R		0.32
gMVP		0.28

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

Publications

LitVar

Other links and lift over

dbSNP: rs1554821462; hg19: chr9-135204682;