Sister chromatid exchange (SCE) and structural chromosome aberration in mutagenicity testing

Abstract

Data from previous studies published on the induction by mutagens of sister chromatid exchanges (SCEs) and structural chromosome damage were compared qualitatively and quantitatively. Although a good correlation between the incidence of both cytogenetic phenomena has been pointed out in many previous publications, about 30% of the agents for which comparable data were available yielded non-corresponding qualitative results concerning both indicator effects. However, even in groups with good qualitative agreement distinct quantitative differences indicated different molecular mechanisms of the formation of SCEs and breaks. Additional information supporting the importance of these differences for the validity of both indicator systems has been derived from the results obtained using strong clastogens exhibiting a low or no SCE-inducing activity and vice versa, from special observations on chromosomal breakage syndromes, and from studies on the action of known co- and anti-clastogens on SCE-induction by chemical mutagens. As a result, it has been suggested that the SCE-technique should be considered as a valuable additional method for cytogenetic mutagenicity testing, which, however, is not adequate to replace the classical methods of analysis of structural chromosome damage.

Chromosome aberrations in lymphocytes of nurses handling cytostatic agents.

“…The clastogenic effect of several cytostatic agents has been documented (2,4,7,15,19). The present results, together with those of previous studies, suggest that even seemingly small doses can change genetic material.…”

“…In the present study the known environmental factors, such as radiation, viral diseases, chemicals, drugs, and smoking (7,13), were evaluated carefully. With respect t o these factors there were n o clear group differences which could explain the greater number of chromosome breaks in the oncologic nurses.…”

“…Cytostatic agent5 have been shown to cause chromosome aberrations and sister chromatid exchanges both in vitro (2,3,7,16,19) and in cells of patients after cytostatic therapy (1, 4, 8, 9, 10, 14, 15, 16).…”

Sister chromatid exchange and ultrasound.

“…They are not generally associated with cell death. 3 SCEs induced bv a number of chemicals exhibit a clear dose -re.sponse relationship, irrespective of whether cells are exposed in vivo or in vitro; 1 and 463 then generally provide a more sensitive indication of chemical exposure than chromosom e aberrations. Th's sensitivity often results in observations of high SCE frequen cies at chemical concentrations that induce few,.…”

“…Although most investigators believe that an increased SCE frequency indicates chromosome damage, the biological significance of SCE is not clear. 1 Certain powerful mutagens, such as ionizing rudiation and some chemicals, cause only small increases in SCE frequency, whereas some weak carcinogens readily induce SCEs.…”