The JAK2 V617F mutation enhanced DC3 production and caused a bias toward erythrocytes and megakaryocytes. The patient-specific iPS cell-derived DC3 are expected to allow studying DC3 in human diseases and developing novel therapeutics. Keywords: induced pluripotent stem cell, iPS cells, hematopoiesis, dendritic cells, DC3, JAK2, JAK2 V617F