Phenotypes Associated with This Genotype

Genotype
MGI:4818803

• Allelic Composition: Jak2^tm1.2Ble/Jak2⁺
• Genetic Background: involves: 129S6/SvEvTac * C57BL/6 * FVB/N

• ♀: phenotype observed in females
• ♂: phenotype observed in males
• N: normal phenotype

mortality/aging

premature death ( J:160883 )

• median survival is 146 days

neoplasm

increased hemolymphoid system tumor incidence ( J:160883 )

• all develop a myeloproliferative neoplasm

• these myeloproliferative neoplasms can be transplanted by transfer of either unfractionated bone marrow cells or LSK cells but not by transfer of MEP or granulocyte/macrophage progenitor cells

• however, acute leukemia is not detected

hematopoietic system

hematopoietic system phenotype ( J:160883 )

N • despite the increase in megakaryocyte numbers no increases in platelet counts are detected

abnormal definitive hematopoiesis ( J:160883 )

• expansion of the megakaryocytic/erythroid progenitor (MEP) population

• disproportional increase in the number of erythroid progenitors relative to other myeloid progenitor

abnormal erythropoiesis ( J:160883 )

• increase in the number of erythroid precursors in the bone marrow and spleen

• marked erythroid hyperplasia in the splenic red pulp

extramedullary hematopoiesis ( J:160883 )

• prominent splenic extramedullary hematopoiesis

abnormal megakaryocyte morphology ( J:160883 )

• megakaryocytes with atypical nuclear features are present in the bone marrow

increased megakaryocyte cell number ( J:160883 )

• mild hyperplasia in the splenic red pulp

increased erythroid progenitor cell number ( J:160883 )

increased hematocrit ( J:160883 )

increased leukocyte cell number ( J:160883 )

abnormal spleen morphology ( J:160883 )

• overall effacement of the normal architecture

enlarged spleen ( J:160883 )

abnormal spleen red pulp morphology ( J:160883 )

• marked erythroid and mild megakaryocytic hyperplasia in the splenic red pulp

abnormal hematopoietic system physiology ( J:160883 )

• MEPs show EPO hypersensitivity

• gene set enrichment analysis indicates that hematopoietic differentiation in the LSK compartment is altered

enhanced megakaryocyte emperipolesis ( J:160883 )

• megakaryocytes with prominent emperipolesis are present in the bone marrow

immune system

increased leukocyte cell number ( J:160883 )

abnormal spleen morphology ( J:160883 )

• overall effacement of the normal architecture

enlarged spleen ( J:160883 )

abnormal spleen red pulp morphology ( J:160883 )

• marked erythroid and mild megakaryocytic hyperplasia in the splenic red pulp

growth/size/body

enlarged spleen ( J:160883 )

Mouse Models of Human Disease		DO ID	OMIM ID(s)	Ref(s)
polycythemia vera		DOID:8997	OMIM:263300	J:160883