X-25013000-C-T

Variant summary

Our verdict is Pathogenic. Variant got 18 ACMG points: 18P and 0B. PM1 PM2 PM5 PP3_Strong PP5_Very_Strong

The NM_139058.3(ARX):c.995G>A(p.Arg332His) variant causes a missense change. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R332G) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 24)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: ARX NM_139058.3 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 5.77

Genes affected

ARX (HGNC:18060): (aristaless related homeobox) This gene is a homeobox-containing gene expressed during development. The expressed protein contains two conserved domains, a C-peptide (or aristaless domain) and the prd-like class homeobox domain. It is a member of the group-II aristaless-related protein family whose members are expressed primarily in the central and/or peripheral nervous system. This gene is thought to be involved in CNS development. Expansion of a polyalanine tract and other mutations in this gene cause X-linked cognitive disability and epilepsy. [provided by RefSeq, Jul 2016]

ACMG classification

Verdict is Pathogenic. Variant got 18 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_139058.3
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chrX-25013001-G-C is described in ClinVar as [Likely_pathogenic]. Clinvar id is 1494703.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant X-25013000-C-T is Pathogenic according to our data. Variant chrX-25013000-C-T is described in ClinVar as [Pathogenic]. Clinvar id is 11192.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chrX-25013000-C-T is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ARX	NM_139058.3	c.995G>A	p.Arg332His	missense_variant	2/5	ENST00000379044.5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ARX	ENST00000379044.5	c.995G>A	p.Arg332His	missense_variant	2/5	1	NM_139058.3	P1

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1087038 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 355172

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 24

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Genetic Services Laboratory, University of Chicago

Feb 08, 2013

- -

X-linked lissencephaly with abnormal genitalia Pathogenic:1

Pathogenic, no assertion criteria provided

literature only

OMIM

Feb 01, 2012

- -

Intellectual disability, X-linked, with or without seizures, arx-related;C3463992:Developmental and epileptic encephalopathy, 1 Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Invitae

Apr 26, 2022

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 expected to disrupt ARX protein function. This sequence change replaces arginine, which is basic and polar, with histidine, which is basic and polar, at codon 332 of the ARX protein (p.Arg332His). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with ARX-related conditions (PMID: 12379852, 32139178). In at least one individual the variant was observed to be de novo. ClinVar contains an entry for this variant (Variation ID: 11192). Experimental studies have shown that this missense change affects ARX function (PMID: 22252899). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.71	D
BayesDel_noAF	Pathogenic	0.78
Cadd	Pathogenic	33
Dann	Pathogenic	1.0
DEOGEN2	Pathogenic	0.96	D
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.94	D
M_CAP	Pathogenic	0.98	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	4.3	H
MutationTaster	Benign	1.0	A
PrimateAI	Pathogenic	0.96	D
PROVEAN	Uncertain	-3.8	D
REVEL	Pathogenic	0.96
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.0040	D
Polyphen		1.0	D
Vest4		0.91
MutPred		0.97		Gain of ubiquitination at K327 (P = 0.0247);
MVP		1.0
MPC		2.4
ClinPred		1.0	D
GERP RS		3.9
Varity_R		0.95
gMVP		0.96

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: rs111033612; hg19: chrX-25031117;