1-160127591-C-T

Variant names:

• chr1-160127591-C-T
• rs777400961
• NM_000702.4:c.788C>T

Variant summary

Our verdict is Pathogenic. The variant received 17 ACMG points: 17P and 0B. PM1 PM2 PP2 PP3_Strong PP5_Very_Strong

The NM_000702.4(ATP1A2):​c.788C>T​(p.Thr263Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,886 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 14/22 in silico tools predict a damaging outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★). Synonymous variant affecting the same amino acid position (i.e. T263T) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ATP1A2 NM_000702.4 missense
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:5
• Conservation: PhyloP100: 7.88
• Publications: 1 publications found

Genes affected

ATP1A2 (HGNC:800): (ATPase Na+/K+ transporting subunit alpha 2) The protein encoded by this gene belongs to the family of P-type cation transport ATPases, and to the subfamily of Na+/K+ -ATPases. Na+/K+ -ATPase is an integral membrane protein responsible for establishing and maintaining the electrochemical gradients of Na and K ions across the plasma membrane. These gradients are essential for osmoregulation, for sodium-coupled transport of a variety of organic and inorganic molecules, and for electrical excitability of nerve and muscle. This enzyme is composed of two subunits, a large catalytic subunit (alpha) and a smaller glycoprotein subunit (beta). The catalytic subunit of Na+/K+ -ATPase is encoded by multiple genes. This gene encodes an alpha 2 subunit. Mutations in this gene result in familial basilar or hemiplegic migraines, and in a rare syndrome known as alternating hemiplegia of childhood. [provided by RefSeq, Oct 2008]

ATP1A2 Gene-Disease associations (from GenCC):

• hemiplegic migraine-developmental and epileptic encephalopathy spectrum

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• migraine, familial hemiplegic, 2

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Ambry Genetics, Genomics England PanelApp, Labcorp Genetics (formerly Invitae)
• alternating hemiplegia of childhood 1

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), Genomics England PanelApp
• developmental and epileptic encephalopathy 98

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies

  Inheritance: AR Classification: STRONG, MODERATE Submitted by: G2P, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• alternating hemiplegia of childhood

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial or sporadic hemiplegic migraine

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 17 ACMG points.

• PM1: In a topological_domain Cytoplasmic (size 135) in uniprot entity AT1A2_HUMAN there are 7 pathogenic changes around while only 3 benign (70%) in NM_000702.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the ATP1A2 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 63 curated pathogenic missense variants (we use a threshold of 10). The gene has 10 curated benign missense variants. Gene score misZ: 4.7713 (above the threshold of 3.09). Trascript score misZ: 6.824 (above the threshold of 3.09). GenCC associations: The gene is linked to developmental and epileptic encephalopathy 98, fetal akinesia, respiratory insufficiency, microcephaly, polymicrogyria, and dysmorphic facies, migraine, familial hemiplegic, 2, alternating hemiplegia of childhood, alternating hemiplegia of childhood 1, familial or sporadic hemiplegic migraine, hemiplegic migraine-developmental and epileptic encephalopathy spectrum.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.992
• PP5: Variant 1-160127591-C-T is Pathogenic according to our data. Variant chr1-160127591-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 585463.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000702.4. 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
	ATP1A2	NM_000702.4	MANE Select	c.788C>T	p.Thr263Met	missense	Exon 8 of 23	NP_000693.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ATP1A2	ENST00000361216.8	TSL:1 MANE Select	c.788C>T	p.Thr263Met	missense	Exon 8 of 23	ENSP00000354490.3
	ATP1A2	ENST00000392233.7	TSL:5	c.788C>T	p.Thr263Met	missense	Exon 8 of 23	ENSP00000376066.3
	ATP1A2	ENST00000472488.5	TSL:2	n.891C>T		non_coding_transcript_exon	Exon 8 of 20

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461886 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727244

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: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:5

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Jul 26, 2018

Athena Diagnostics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Jul 30, 2025

GeneDx

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Published functional studies demonstrate a damaging effect on protein function (PMID: 22117059, 18728015); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 24096472, 22067897, 18728015, 16088919, 22117059)

Developmental and epileptic encephalopathy 98 Pathogenic:1

Mar 24, 2025

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Criteria applied: PS3_MOD,PS4_MOD,PM2_SUP,PP2,PP3

Migraine, familial hemiplegic, 2 Pathogenic:1

Jan 09, 2023

Institute of Human Genetics, University of Leipzig Medical Center

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

_x000D_ Criteria applied: PS3_MOD, PS4_MOD, PM1, PP1_MOD, PM2_SUP, PP3

Familial hemiplegic migraine Pathogenic:1

Nov 27, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces threonine, which is neutral and polar, with methionine, which is neutral and non-polar, at codon 263 of the ATP1A2 protein (p.Thr263Met). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individuals with clinical features of autosomal dominant familial hemiplegic migraine (PMID: 16088919; Invitae). ClinVar contains an entry for this variant (Variation ID: 585463). 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 ATP1A2 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects ATP1A2 function (PMID: 18728015, 22117059). In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic.

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.53	D
BayesDel_noAF	Pathogenic	0.52
CADD	Pathogenic	32
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.98	D
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Pathogenic	1.0	D
M_CAP	Pathogenic	0.67	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	4.6	H
PhyloP100		7.9
PrimateAI	Pathogenic	0.89	D
PROVEAN	Pathogenic	-5.0	D
REVEL	Pathogenic	0.95
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.99
MutPred		0.97		Gain of MoRF binding (P = 0.0976)
MVP		0.98
MPC		1.9
ClinPred		1.0	D
GERP RS		4.9
PromoterAI		0.068	Neutral
Varity_R		0.90
gMVP		0.99
Mutation Taster		=3/97	disease causing (ClinVar)

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: rs777400961; hg19: chr1-160097381;