Hybridization of a probe containing dInosine is sensitive to mismatches neighboring the dInosine position, aiding specificity It has been shown above that when the dInosine and the mismatch have the same distribution pattern, i.e. the dInosine masks the mismatch, hybridization can be restored (Figures 2A, B, 3A and B). We analyzed how many mismatches outside the rescuing position of dInosine (mismatch outside dInosine; mmoi) a probe can tolerate. Norovirus, Ino18 and InflA probes were tested against a set of targets whose sequences were designed to range successively from a Norovirus sequence to the InflA sequence, allowing different amounts of mismatch and mmoi to be analyzed. Norovirus is a highly variable, positive-sense RNA virus belonging to the Caliciviridae, which causes 'winter vomiting disease'. The Norovirus sequence chosen (the capsid gene of the Norwalk-like virus, accession nr AY274264), after Blastn with the InflA probe sequence, has a short region of 8 nt that perfectly matches the end region of the InflA probe and has 10 dispersed matching nt ( Figure 4A ). The Norovirus target (70) 0_36_52 (0.8) (this code is explained below, and in the legend to Figure 4 ) was gradually changed to resemble the InflA target (0.8) 51_0_0 (70) by altering the central nt sequence. A set of targets was also created where the nine nt at the 5 0 end were changed into an InflA sequence and the central region was gradually changed from the Norovirus to the Influenza sequence, starting with (0.61) 9_27_42 (9.8). The targets were named according to the number of matching and mismatching nt in comparison with the three probes: (nt matching those of the Norovirus probe at 5 0 and 3 0 ) mismatching nt versus the Norovirus probe_Ino18 probe_InflA probe (nt matching those of the InflA probe at 5 0 and 3 0 ) (see Figure 4A ; nt sequences in Supplementary Table S3A and B) .