Organisms containing an increase in DNA content by whole number multiples of the entire
set of chromosomes are defined as polyploid. Cells that contain more than two sets of
chromosomes were first observed in plants about a century ago, and it is now recognized
that polyploid cells form in many eukaryotes under a wide variety of circumstances. Although
it is less common in mammals, some tissues, including the liver, show a high percentage of
polyploid cells. Thus, during post-natal growth, the liver parenchyma undergoes dramatic …