ANALYSIS OF COLCHICINE-INDUCED CHROMOSOMAL-ABERRATIONS IN EMBRYOS OBTAINED FROM XO MICE

A high incidence of chromosomal anomalies has been observed in the off spring of our XO mouse colony, However, the reason(s) are unknown. We hypothesized that XO dams might be more susceptible to certain chromos omal mutagens, Therefore, we assessed whether the oocytes of XO mice a re more susceptible to colchicine, Pregnant XO and XX mice were intrap eritoneally (i.p.) injected with colchicine, 0.2 mg/kg, 6 h after mati ng (between resumption of meiosis II and extrusion of the second polar body), Contrary to our expectation, the incidence of chromosomal anom alies induced by colchicine exposure did not differ between XX and XO dams, These findings suggest that the chromosomal stability of the ooc ytes from XO mice may not be affected by colchicine exposure at the st age of extrusion of the second polar body, The effects of chromosomal imbalance inherent in XO mice on chemical susceptibilities should be f urther investigated. (C) 1998 Elsevier Science Inc.