The result of this process is the removal of a whole genome from a cell. The most known example is the enucleation process of erythrocytes. A processed stem cell goes through changes causing it to lose a nucleus. In the beginning phase, pro-erythroblast goes through another mitotic divisions, in which an erythroblast with a smaller nucleus is created and moved to the side of the cell. The nucleus becomes isolated from cytoplasm and then erythroblast is divided into reticulocyte with cytoplasm and pyrenocyte with condensed nucleus. Pyrenocyte with all genetic material from cell is degraded then by a macrophage. Loss of genome is in this case advantageous, since pyrenocyte can accumulate more hemoglobin. Mature red blood cell without a nucleus, can properly deliver oxygen.
