Chromosome studies of bone marrow cells and peripheral blood lymphocytes from diphenylhydantoin-treated patients

Chromosome studies were performed on both bone-marrow cells and peripheral blood lymphocytes from ten patients with epilepsy, treated with diphenylhydantoin alone. There was no evidence of chromosome damage. Furthermore, the bone-marrow smears from five of the patients were studied for the presence of micronuclei. There was no increase in the number of micronuclei compared with control persons. Conflicting results about the cytogenetic effect of diphenylhydantoin have appeared in the literature. It is emphasized that, in studies on the chromosome-damaging effect of chemical agents in man, bone-marrow cells seem to be most indicative of the conditions in vivo.