9-5126378-G-A

Variant names:

• chr9-5126378-G-A
• rs775568041
• NM_004972.4:c.3223G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 1P and 4B. PP3 BS2

The NM_004972.4(JAK2):​c.3223G>A​(p.Val1075Met) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000617 in 1,459,146 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: 0.0000062 (0 hom.)
• Consequence: JAK2 NM_004972.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.59
• Publications: 3 publications found

Genes affected

JAK2 (HGNC:6192): (Janus kinase 2) This gene encodes a non-receptor tyrosine kinase that plays a central role in cytokine and growth factor signalling. The primary isoform of this protein has an N-terminal FERM domain that is required for erythropoietin receptor association, an SH2 domain that binds STAT transcription factors, a pseudokinase domain and a C-terminal tyrosine kinase domain. Cytokine binding induces autophosphorylation and activation of this kinase. This kinase then recruits and phosphorylates signal transducer and activator of transcription (STAT) proteins. Growth factors like TGF-beta 1 also induce phosphorylation and activation of this kinase and translocation of downstream STAT proteins to the nucleus where they influence gene transcription. Mutations in this gene are associated with numerous inflammatory diseases and malignancies. This gene is a downstream target of the pleiotropic cytokine IL6 that is produced by B cells, T cells, dendritic cells and macrophages to produce an immune response or inflammation. Disregulation of the IL6/JAK2/STAT3 signalling pathways produces increased cellular proliferation and myeloproliferative neoplasms of hematopoietic stem cells. A nonsynonymous mutation in the pseudokinase domain of this gene disrupts the domains inhibitory effect and results in constitutive tyrosine phosphorylation activity and hypersensitivity to cytokine signalling. This gene and the IL6/JAK2/STAT3 signalling pathway is a therapeutic target for the treatment of excessive inflammatory responses to viral infections. Alternative splicing results in multiple transcript variants encoding distinct isoforms. [provided by RefSeq, Jul 2020]

INSL6 (HGNC:6089): (insulin like 6) The protein encoded by this gene contains a classical signature of the insulin superfamily and is significantly similar to relaxin and relaxin-like factor. This gene is preferentially expressed in testis. Its expression in testis is restricted to interstitial cells surrounding seminiferous tubules, which suggests a role in sperm development and fertilization. [provided by RefSeq, Jul 2008]

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.825
• BS2: High AC in GnomAdExome4 at 9 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
JAK2	NM_004972.4	c.3223G>A	p.Val1075Met	missense_variant	Exon 24 of 25	ENST00000381652.4	NP_004963.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
JAK2	ENST00000381652.4	c.3223G>A	p.Val1075Met	missense_variant	Exon 24 of 25	1	NM_004972.4	ENSP00000371067.4
JAK2	ENST00000487310.1	n.414G>A		non_coding_transcript_exon_variant	Exon 1 of 2	2
INSL6	ENST00000649639.1	c.*11-1867C>T		intron_variant	Intron 3 of 3			ENSP00000497955.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000802 AC: 2 AN: 249322 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000292

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000888

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000617 AC: 9 AN: 1459146 Hom.: 0 Cov.: 29 AF XY: 0.00000276 AC XY: 2 AN XY: 725914

African (AFR) AF: 0.00 AC: 0 AN: 33300

American (AMR) AF: 0.0000225 AC: 1 AN: 44474

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26020

East Asian (EAS) AF: 0.00 AC: 0 AN: 39546

South Asian (SAS) AF: 0.00 AC: 0 AN: 86002

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53384

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00000630 AC: 7 AN: 1110404

Other (OTH) AF: 0.0000166 AC: 1 AN: 60258

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000509 Hom.: 0

Bravo AF: 0.00000756

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Jun 21, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces valine, which is neutral and non-polar, with methionine, which is neutral and non-polar, at codon 1075 of the JAK2 protein (p.Val1075Met). This variant is present in population databases (no rsID available, gnomAD 0.003%). This variant has not been reported in the literature in individuals affected with JAK2-related conditions. 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 JAK2 protein function with a negative predictive value of 80%. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.85
BayesDel_addAF	Uncertain	0.079	D
BayesDel_noAF	Uncertain	-0.040
CADD	Pathogenic	30
DANN	Pathogenic	1.0
DEOGEN2	Uncertain	0.70	D
Eigen	Pathogenic	0.69
Eigen_PC	Pathogenic	0.69
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Benign	0.052	D
MetaRNN	Pathogenic	0.82	D
MetaSVM	Uncertain	0.29	D
MutationAssessor	Benign	1.2	L
PhyloP100		9.6
PrimateAI	Pathogenic	0.86	D
PROVEAN	Benign	-1.9	N
REVEL	Uncertain	0.64
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.012	D
Polyphen		1.0	D
Vest4		0.68
MutPred		0.60		Loss of catalytic residue at V1075 (P = 0.0441);
MVP		0.84
MPC		0.71
ClinPred		0.79	D
GERP RS		5.4
Varity_R		0.86
gMVP		0.69
Mutation Taster		=23/77	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs775568041; hg19: chr9-5126378;