SINGLE-CELL GEL-ELECTROPHORESIS ASSAY - SENSITIVITY OF PERIPHERAL WHITE BLOOD-CELLS IN HUMAN-POPULATION STUDIES

The single cell gel electrophoresis assay (Comet assay) was selected a s a biomarker of exposure to evaluate the impact of air pollution and lifestyle variables on hospitalized pregnancies in two districts,vith different air pollution levels in northern (Teplice) and southern (Pra chatice) Bohemia, The hypothesis was that the DNA damage detected as s ingle strand breaks would be generally higher in the district with hig her air pollution levels. To undertake the study we enrolled 322 pregn ancies in Teplice and 220 in Prachatice, Venous and cord blood were an alysed using the original alkaline Comet assay procedure with lysis fo r 60 min, unwinding for 40 min and electrophoresis for 24 min, We also used a modified procedure in which unwinding was prolonged to 60 min and electrophoresis to 40 min, Peripheral white blood cells (WBC) were analysed using an image analyser system, When we analysed the results obtained for mothers and their children no differences were found bet ween polluted and control districts, The prolongation of alkali unwind ing and electrophoresis did not increase sensitivity of the assay, No effects of prematurity, ethnicity, smoking or GSTM1 polymorphism were observed for any of the Comet parameters, Multiple regression analyses were performed for the European population (n = 285). A statistical m odel was fitted to determine the relationship between the Comet parame ters of mothers and their children, According to our results it seems that the Comet assay was not a particularly sensitive technique to det ermine the effects of environmental pollution at the DNA level if peri pheral WBC are used.