Several compounds used clinically in drug abuse therapy were evaluated for genetic activity in a series of in vivo and in vitro assays. The second report in this series describes the results for one of these compounds, Methadone. A previous report described the results for Naltrexone. Methadone is a synthetic narcotic analgesic used as a substitute for Heroin in drug detoxification programs. Methadone demonstrated weak activity in the E. coli DNa repair system and in the Neurospora crassa and the mouse lymphoma forward-mutation assays under the conditions of this evaluation. Additional analysis of the ad-3 mutants induced by a related compound, LAAM, in Neurospora indicated that they were the result of a parasexual phenomena rather than forward mutation. Therefore, the methadone-induced ad-3 mutants also may be due to a parasexual phenomena.

Several compounds used clinically in drug abuse therapy were evaluated for genetic activity in a series of in vivo and in vitro assays. This third report in the series describes the results for one of these compounds, LAAM (L-alpha-acetyl methadol). Previous reports described results from a three phase testing program for Naltrexone and Methadone. LAAM is related chemically to the narcotic analgesic oxymorphine, and is related chemically to a narcotic antagonist, naloxone. LAAM exhibited genetic activity in the ad-3 forward-mutation test in Neurospora crassa and also was weakly mutagenic in the mouse lymphoma forward-mutation assay. Further analysis of the ad-3 mutants from N. crassa indicated that they were the result of a parasexual phenomenon rather than forward mutation. There was one confirmed translocation carrier in the heritable translocation study, which by conservative interpretation might imply some germ-cell risk associated with exposure to LAAM.