Failure of cells to cleave at the end of mitosis is dangerous to the organism because it immediately produces tetraploidy and centrosome amplification, which is thought to produce genetic imbalances. Using normal human and rat cells, we reexamined the basis for the attractive and increasingly accepted proposal that normal mammalian cells have a "tetraploidy checkpoint" that arrests binucleate c...

STUDY QUESTION How does tetraploidy develop in hydatidiform moles (HMs), and what is the frequency of the different origins? SUMMARY ANSWER Most molar pregnancies with tetraploid cells appear to be produced by somatic endoreduplications, while a minority originate from a tetraploid zygote. The frequency of zygotic tetraploidy was estimated to be 0.7%. WHAT IS KNOWN ALREADY The parental orig...

In vitro studies on skin cultures established from 49 members from Kindred 109, in whom the Gardner syndrome was first delineated, showed that increased in vitro tetraploidy occurred only in those cultures derived from branches with the full expression of the Gardner gene (colorectal polyps with multiple extracolorectal benign tumours) and not in those derived from branches showing only extraco...

Tetraploid cells, which contain a doubled chromosomal content, are known to facilitate tumorigenesis [1]. Two specific characteristics of tetraploid cells play major roles in promoting neoplastic transformation. First, proliferating tetraploid cells are genomically unstable and accumulate both numerical and structural chromosomal abnormalities. Such chromosomal instability arises mainly due to ...