Dimethylsulfoxide induces aneuploidy in a fungal test system.

Errors in chromosome segregation leading to numerical anomalies appear to be unusually frequent in Man and consequently a large proportion of conceptions in our species are aneuploid. Concern has been expressed that this frequency may be increased still further following exposure to inducing substances (trisomigens) present in the environment. We have been developing a fungal test system to screen for such trisomigens and in this paper we report its use in detecting induction following exposure to dimethylsulfoxide (DMSO). In our system DMSO induces segregational errors at both the first and second meiotic division. The results also show that increases in aneuploidy are proportional to the underlying spontaneous frequency. If this finding is generally true it will be especially important to avoid exposure to trisomigens as Man might be especially vulnerable to them.