NM_139058.3:c.997A>T

Variant names:

• chrX-25012998-T-A
• NM_139058.3:c.997A>T
• ARX p.Thr333Ser

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PS1 PM1 PM2 PM5 PP3_Strong

The NM_139058.3(ARX):​c.997A>T​(p.Thr333Ser) 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. T333A) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 24)
• Consequence: ARX NM_139058.3 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 5.71
• Publications: 0 publications found

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]

ARX Gene-Disease associations (from GenCC):

• genetic developmental and epileptic encephalopathy

  Inheritance: AD, XL Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• intellectual disability, X-linked, with or without seizures, ARX-related

  Inheritance: XL Classification: DEFINITIVE, MODERATE Submitted by: G2P, Ambry Genetics
• Partington syndrome

  Inheritance: XL Classification: DEFINITIVE, SUPPORTIVE Submitted by: G2P, Orphanet
• X-linked complex neurodevelopmental disorder

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• X-linked lissencephaly with abnormal genitalia

  Inheritance: XL Classification: STRONG, MODERATE, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp, Ambry Genetics
• infantile spasms

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• corpus callosum agenesis-abnormal genitalia syndrome

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• infantile epileptic-dyskinetic encephalopathy

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• non-syndromic X-linked intellectual disability

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet
• X-linked spasticity-intellectual disability-epilepsy syndrome

  Inheritance: XL Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PS1: Transcript NM_139058.3 (ARX) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 6 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 3 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-25012997-G-T is described in ClinVar as Pathogenic. ClinVar VariationId is 11200.Status of the report is criteria_provided_single_submitter, 1 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.953

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_139058.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ARX	NM_139058.3	MANE Select	c.997A>T	p.Thr333Ser	missense	Exon 2 of 5	NP_620689.1	Q96QS3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ARX	ENST00000379044.5	TSL:1 MANE Select	c.997A>T	p.Thr333Ser	missense	Exon 2 of 5	ENSP00000368332.4	Q96QS3

Frequencies

GnomAD3 genomes Cov.: 24

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 24

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	1.0
BayesDel_addAF	Pathogenic	0.62	D
BayesDel_noAF	Pathogenic	0.66
CADD	Pathogenic	28
DANN	Uncertain	0.98
DEOGEN2	Pathogenic	0.92	D
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Uncertain	0.93	D
M_CAP	Pathogenic	0.97	D
MetaRNN	Pathogenic	0.95	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Uncertain	2.8	M
PhyloP100		5.7
PrimateAI	Pathogenic	0.96	D
PROVEAN	Uncertain	-3.2	D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0	D
Varity_R		0.84
gMVP		0.87
Mutation Taster		=28/72	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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chrX-25031115;