The cybrid technique can be used to evaluate the functional consequences of different mtDNA molecules. To perform this type of cybrid study, a cell line is depleted of its endogenous mtDNA; these mtDNA-depleted cells are called ρ0 cells. ρ0 cells are then mixed with non-nucleated cytoplasts or cells (such as platelets) in the presence of a detergent, which disrupts membranes. This facilitates incorporation of non-nucleated cell mitochondria, which contain mtDNA, within the cytosol of the nucleated cells. The transferred mtDNA repopulates the nucleated cell to create a “cytoplasmic hybrid”, or cybrid. Cybrid cell lines containing mtDNA from different sources vary only in the origination of their mtDNA, since the nuclear DNA is equivalent between the cell lines. Each line that is generated can be expanded for use in biochemical or molecular assays. Functional differences between cell lines are believed to reflect and arise through differences in their mtDNA. Nuc=nucleus; Con=control; Plt=platelet; AD=Alzheimer’s disease.