Cytogenetic effects of methotrexate on human cells in vivo: comparison between results obtained by chromosome studies on bone-marrow cells and blood lymphocytes and by the micronucleus test
Jensen, M.K.; Nyfors, A.
Mutation Research 64(5): 339-343
Cytogenetic studies were performed in 22 patients (1 with polymyositis, the remainder with psoriasis vulgaris) treated with methotrexate (MTX). In some patients, metaphases from both bone marrow cells and peripheral blood cells were studied. In bone marrow preparations an increased number of structural chromosomal aberrations was present, whereas abnormalities were not observed in the peripheral blood cells. An examination of the bone marrow chromosomes must be included in the study of the possible chromosome-breaking effect of chemical agents. The results obtained with the micronucleus test and chromosome studies were compared in 10 patients treated with MTX. The micronucleus test was more sensitive than the chromosome analysis with regards to the clastogenic effect of MTX.