Variability of cell generation times in a hepatoma cell pedigree

Time-lapse cinematographic analysis of a clone of HTC rat hepatoma cells showed variations in interdivision time within the clone. A positive correlation was found between the interdivision times of mother and daughter cells. The variability of the differences between interdivision times of cells of sister, cousin, second cousin or second-second cousin relationship was calculated. The proportion of cells with large differences in intermitotic times was found to increase with decreasing relationship. The clonal division pattern observed suggests strongly that 'inherited' factors goven the process leading to cell division but that their effects can be modified.