We note that sometimes non-specific amplification can also take place, especially where the target DNA is absent (see Figure 3 ) and there is low amounts of DNA present in the reaction (cf Figures 3a and 4) . These do not form the specific banding patterns representing the different multimeric LAMP products that are characteristic for each assay and thus can be easily distinguished on a gel. Alternative banding patterns have been observed, also for low template reactions; analyses of these products show that they are formed by interactions of the primers used [8] , to form LAMP equivalents of primer-dimers. Two factors seem to be important: in the absence of target, low background DNA may aid the formation of non-specific products that go on to be amplified; and freeze-thaw repetitions may induce damage to the primers to permit the formation of 'primer intermediates' which can then be amplified. Since LAMP is capable of non-specific amplification, techniques that rely on the detection of by-products of DNA synthesis, e.g., the use of magnesium pyrophosphate precipitation [9] or the use of SyBr Green dye [10] may not be able to distinguish between real and Right border sequences of MS8 and RF3 Figure 1 Right border sequences of MS8 and RF3. Sequences of the plant (above) and transgene (below) at the right border junctions for MS8 and RF3. Highlighted sequences are the targets of the LAMP primers. The plant sequences are those shown in Table 1 : dark blue bases highlighted are the outer displacement primers, yellow and green sequences are the 5' and 3' ends of the LAMP primers respectively, and light blue sequences depict the loop primers. The sensitivity of the LAMP assay and its suitability for practical GMO detection was tested using assays for commonly-used sequence motifs, the CaMV 35S promoter (P-35S) and the Agrobacterium promoter and terminator for the nopaline synthase gene (P-nos and T-nos, respectively). These sequences are commonly used in constructs used to create approved GM events (see [11] ). RoundUp Ready™ soya construct contains both P-35S and T-nos so provided convenient template for testing the assays. We used a sample where the copy number of the GM has been well characterized and thus control the number of template in each reaction.