In most animals, somatic cell centrosomes are inherited from the centriole of the fertilizing spermatozoa. The oocyte centriole degenerates during oogenesis, and completely disappears in metaphase II. Therefore, the embryos generated by in vitro parthenogenesis are supposed to develop without any centrioles. Exceptional acentriolar and/or acentrosomal developments are possible in mice and in some experimental cells; however, in most animals, the full developmental potential of parthenogenetic cells in vitro and the fate of their centrioles/centrosomes are not clearly understood. To predict the future of in vitro human parthenogenesis, we explored the centrioles/centrosomes in ovarian mature cystic teratoma cells by immunofluorescent staining and transmission electron microscopy. We confirmed the presence of centrioles and centrosomes in these well-known parthenogenetic ovarian tumor cells. Our findings clearly demonstrate that, even without a sperm centriole, parthenotes that develop from activated oocytes can produce their own centrioles/centrosomes, and can even develop into the well-differentiated mature tissue. (C) 2011 Elsevier Inc. All rights reserved.