Premature chromosome condensation (PCC), also known as premature mitosis, occurs in eukaryotic organisms when mitotic cells fuse with interphase cells. Chromatin, a substance that contains genetic material such as DNA, is normally found in a loose bundle inside a cell's nucleus. During the prophase of mitosis, the chromatin in a cell compacts to form condensed chromosomes; this condensation is required in order for the cell to divide properly. While mitotic cells have condensed chromosomes, interphase cells do not. PCC results when an interphase cell fuses with a mitotic cell, causing the interphase cell to produce condensed chromosomes prematurely.