HETEROGENEITY IN CHEMICAL MUTAGEN-INDUCED CHROMOSOME-DAMAGE AFTER G(2) PHASE EXPOSURE TO BLEOMYCIN, ARA-C AND GENTIAN-VIOLET IN CULTURED LYMPHOCYTES OF BETA-THALASSEMIA TRAITS

Chemical mutagen-induced chromosome damage was analysed in cultured peripheral blood lymphocytes from beta-thalassaemia traits and healthy individuals. This was prompted by the fact that beta-thalassaemia trait is present in 1-17% of different population groups in India. To study mutagen-induced chromosome instability, G(2) lymphocytes were exposed to bleomycin, ara-C or gentian violet in 48-h cultures. Spontaneous chromosome aberration frequencies in lymphocytes from beta-thalassaemia traits were found to be in the normal range. In all three clastogen-treated lymphocytes from beta-thalassaemia traits, there is a degree of hypersensitivity, when the results are averaged over a number of individuals, but some individuals overlap within the normal range. The heterogeneity in chemical mutagen sensitivity observed in beta-thalassaemia traits is discussed in terms of the oxidative damage consequent on the genetic and biochemical features peculiar to the beta-thalassaemia trait cell.