Detailed Review Paper on the miniaturised versions of the bacterial reverse gene mutation test

The bacterial reverse gene mutation test described in OECD Test Guideline 471 is the most widely used in vitro test for the detection of mutagenicity. The standard format utilises plate incorporation and/or preincubation method; a test mixture containing bacteria, test chemical, S9-mix, when required, and agar, is plated on 90- to 100-mm plates. Several miniaturised versions of the assay have been developed and are already in use, particularly for early screening of new products, as during research and development, large numbers of chemicals have to be tested that are often only available in low amounts. The primary advantage of these miniaturised versions is a significant reduction of the amount of test material needed to conduct the experiments; some may also allow simultaneous analyses of large number of samples, increasing throughput and reducing resources and cost. The aim of this Detailed Review Paper (DRP) was to evaluate the performance of several types of miniaturised assays, relative to the standard bacterial reverse gene mutation test specified in OECD TG 471. Performance evaluations were based on a retrospective analysis of data provided by well-established genotoxicity testing laboratories.