chr1-160135242-G-T

Variant names:

• chr1-160135242-G-T
• rs200425518
• NM_000702.4:c.2062G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 7 ACMG points: 7P and 0B. PM1 PM2 PP2 PP3_Moderate

The NM_000702.4(ATP1A2):​c.2062G>T​(p.Ala688Ser) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000342 in 1,461,894 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: ATP1A2 NM_000702.4 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:3
• Conservation: PhyloP100: 9.98
• Publications: 0 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: Likely_pathogenic. The variant received 7 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, 4 uncertain 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, 0.914

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.2062G>T	p.Ala688Ser	missense	Exon 15 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.2062G>T	p.Ala688Ser	missense	Exon 15 of 23	ENSP00000354490.3
	ATP1A2	ENST00000392233.7	TSL:5	c.2062G>T	p.Ala688Ser	missense	Exon 15 of 23	ENSP00000376066.3
	ATP1A2	ENST00000447527.1	TSL:2	c.1192G>T	p.Ala398Ser	missense	Exon 8 of 16	ENSP00000411705.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251356 AF XY: 0.00000736

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000578

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1461894 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727248

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.0000671 AC: 3 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: 53420

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

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112012

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

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Jun 12, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.2062G>T (p.A688S) alteration is located in exon 15 (coding exon 15) of the ATP1A2 gene. This alteration results from a G to T substitution at nucleotide position 2062, causing the alanine (A) at amino acid position 688 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear.

Familial hemiplegic migraine Uncertain:1

Sep 20, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces alanine, which is neutral and non-polar, with serine, which is neutral and polar, at codon 688 of the ATP1A2 protein (p.Ala688Ser). 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 ATP1A2 protein function. ClinVar contains an entry for this variant (Variation ID: 575386). This variant has not been reported in the literature in individuals affected with ATP1A2-related conditions. This variant is present in population databases (rs200425518, gnomAD 0.006%).

Migraine, familial hemiplegic, 2;C3549447:Alternating hemiplegia of childhood 1 Uncertain:1

Oct 31, 2018

Fulgent Genetics, Fulgent Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.72
BayesDel_addAF	Pathogenic	0.23	D
BayesDel_noAF	Pathogenic	0.27
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.81	D
Eigen	Uncertain	0.48
Eigen_PC	Uncertain	0.50
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.91	D
MetaSVM	Benign	-0.54	T
MutationAssessor	Uncertain	2.1	M
PhyloP100		10
PrimateAI	Uncertain	0.71	T
PROVEAN	Benign	-2.3	N
REVEL	Pathogenic	0.85
Sift	Pathogenic	0.0	D
Sift4G	Uncertain	0.012	D
Polyphen		0.99	D
Vest4		0.74
MutPred		0.85		Gain of disorder (P = 0.0499)
MVP		0.86
MPC		1.4
ClinPred		0.94	D
GERP RS		4.5
Varity_R		0.48
gMVP		0.94
Mutation Taster		=12/88	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs200425518; hg19: chr1-160105032;