Sterility in honey bees caused by dimethyl sulfoxide

Honey bee (Apis meillfera) semen was treated as follows: 1) diluted in saline with 10 percent dimethyl sulfoxide (DMSO) and stored at - 196°C; 2) same treatment but stored at 12°C; 3) diluted in saline and stored at 12°C; and 4) undiluted, unstored semen. Daughters (queens) produced from the treated spermatozoa were evaluated for total sterility. Only sterile eggs were produced from 3 percent of the queens in both groups that had DMSO (5/166 in group 1, and 6/ 234 in group 2). They were different (P < 0.05) from groups 3 and 4 in which no queens were produced that laid only sterile eggs (0/151 and 0/ 137, respectively). These results demonstrate that, under the conditions used, a low level of sterility is induced by DMSO, and this F1 sterility raises questions about possible genetic damage by DMSO.