Opiates and human chromosome alterations

Cytogenetic studies on cultured lymphocytes showed an increase in the frequency of chromosome breaks in heroin addicts (2.6%) compared to controls (0.4%). Within the first year, patients on methadone maintenance had a decline in the frequency of chromosome damage. Investigation of former addicts who had not been exposed to heroin for over one year revealed a remarkably low frequency of cells with damage for both methadone users (0.8%) and for those not using methadone (0.6%). These results indicate that long-term treatment programs reverse the cytogenetic alterations found in heroin users.