9-5022081-A-G

Position:

• chr9-5022081-A-G

Variant summary

Our verdict is Benign. Variant got -8 ACMG points: 0P and 8B. BP4_Strong BS2

The NM_001322198.2(JAK2):​c.-1027A>G variant causes a 5 prime UTR premature start codon gain change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000753 in 1,461,640 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000075 (0 hom.)
• Consequence: JAK2 NM_001322198.2 5_prime_UTR_premature_start_codon_gain
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:1
• Conservation: PhyloP100: -0.101

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

Verdict is Benign. Variant got -8 ACMG points.

• BP4: Computational evidence support a benign effect (MetaRNN=0.031151235).
• BS2: High AC in GnomAdExome4 at 11 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
JAK2	NM_004972.4	c.94A>G	p.Met32Val	missense_variant	3/25	ENST00000381652.4	NP_004963.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
JAK2	ENST00000381652.4	c.94A>G	p.Met32Val	missense_variant	3/25	1	NM_004972.4	ENSP00000371067.4
JAK2	ENST00000636127.1	c.94A>G	p.Met32Val	missense_variant	3/16	5		ENSP00000489812.1
JAK2	ENST00000476574.5	c.*16A>G		downstream_gene_variant		3		ENSP00000490624.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.0000119 AC: 3 AN: 251398 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135868

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.0000327

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000753 AC: 11 AN: 1461640 Hom.: 0 Cov.: 30 AF XY: 0.00000825 AC XY: 6 AN XY: 727146

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.0000232

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000312 Hom.: 0

Bravo AF: 0.0000113

ExAC AF: 0.0000247 AC: 3

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Thrombocythemia 3 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Neuberg Centre For Genomic Medicine, NCGM

-

The missense c.94A>G (p.Met32Val) variant in JAK2 gene has not been reported previously as a pathogenic variant nor as a benign variant, to our knowledge. This variant is reported with the allele frequency 0.001% in the gnomAD and novel in 1000 genome database. The amino acid Met at position 32 is changed to a Val changing protein sequence and it might alter its composition and physicochemical properties. For these reasons, this variant has been classified as Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.051
BayesDel_addAF	Benign	-0.31	T
BayesDel_noAF	Benign	-0.59
CADD	Benign	7.4
DANN	Benign	0.34
DEOGEN2	Benign	0.36	.;T
Eigen	Benign	-1.2
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.015	N
LIST_S2	Benign	0.38	T;T
M_CAP	Benign	0.020	T
MetaRNN	Benign	0.031	T;T
MetaSVM	Benign	-0.97	T
MutationAssessor	Benign	-1.4	.;N
PrimateAI	Benign	0.29	T
PROVEAN	Benign	-0.33	.;N
REVEL	Benign	0.22
Sift	Benign	0.80	.;T
Sift4G	Benign	0.49	.;T
Polyphen		0.0	.;B
Vest4		0.094
MutPred		0.30		Gain of methylation at K33 (P = 0.0177);Gain of methylation at K33 (P = 0.0177);
MVP		0.52
MPC		0.18
ClinPred		0.018	T
GERP RS		0.85
Varity_R		0.048
gMVP		0.38

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

Publications

LitVar

Other links and lift over

dbSNP: rs778174935; hg19: chr9-5022081;