Triploidy in human cell line.

Cytogenetic studies of a human amnion cell line (strain RA) indicate that the major stem cell was triploid. Consistently present in the triploid cells were two marker chromosomes, a small centric fragment, and an apparently telocentric D. At various times triploid cells constituted 40 to 80 percent of the cell population. The possible origin of the triplaid cell is a diploid/ triploid mosaic amnion.