rs797045294

Variant names:

• chrX-25013695-C-A
• rs797045294
• NM_139058.3:c.300G>T

Your query was ambiguous. Multiple possible variants found:

• chrX-25013695-C-A
• chrX-25013695-C-G
• chrX-25013695-C-T

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_139058.3(ARX):​c.300G>T​(p.Ala100Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000128 in 779,907 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. A100A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 0.0000013 (0 hom. 0 hem.)
• Consequence: ARX NM_139058.3 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -3.50
• 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: XL, AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• intellectual disability, X-linked, with or without seizures, ARX-related

  Inheritance: XL Classification: DEFINITIVE, MODERATE Submitted by: Ambry Genetics, G2P
• 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: Ambry Genetics, Labcorp Genetics (formerly Invitae), Orphanet, Genomics England PanelApp
• 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: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.69).
• BP7: Synonymous conserved (PhyloP=-3.5 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
ARX	NM_139058.3	c.300G>T	p.Ala100Ala	synonymous_variant	Exon 2 of 5	ENST00000379044.5	NP_620689.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
ARX	ENST00000379044.5	c.300G>T	p.Ala100Ala	synonymous_variant	Exon 2 of 5	1	NM_139058.3	ENSP00000368332.4

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome AF: 0.00000128 AC: 1 AN: 779907 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 234941

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 16226

American (AMR) AF: 0.00 AC: 0 AN: 4781

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 8480

East Asian (EAS) AF: 0.00 AC: 0 AN: 16519

South Asian (SAS) AF: 0.00 AC: 0 AN: 13842

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 12877

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 1748

European-Non Finnish (NFE) AF: 0.00000148 AC: 1 AN: 675287

Other (OTH) AF: 0.00 AC: 0 AN: 30147

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 23

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.69
CADD	Benign	5.1
DANN	Benign	0.89
PhyloP100		-3.5

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: rs797045294; hg19: chrX-25031812;