Increased sister chromatid exchange in megaloblastic anaemia-studies on bone marrow cells and lymphocytes.

Abstract

Sister chromatid exchanges (SCE) and chromosome aberrations were scored in bone marrow cells and phytohaemagglutinin-stimulated lymphocytes of 8 patients with megaloblastic anaemia. Micronuclei were also studied from erythroblast/megaloblast precursors. Unlike the bone marrow cells of the controls, a proportion of the bone marrow cells of patients with megaloblastic anaemia showed evidence of 1) a highly increased (even 10-fold) number of SCE (> 50 per cell), 2) notable chromosome aberrations (i.e. despiralization, centromere separation, chromatid exchanges, and “pulverization”), 3) an increased proportion of micronuclei (1% to 7% as compared to 0% to 0.4% in the controls). The lymphocytes of patients with megaloblastic anaemia also had significantly (P<0.001) higher SCE (mean 9.7) than the controls (mean 7.9), even though these cells had no notable chromosome aberrations.