Figure 1.

The tagged microarray approach. (a) Two alleles are distinguished by PCR using three primers. The biotinylated PCR products are arrayed onto a solid support and hybridised with detector probes, which recognise tags specific to the two products. (b) Structure of a tag primer. The allele-specific region is separated from the tag by a C18 linker. (c) Tag detector probe. Two partially complementary oligonucleotides carry a tag sequence (the A tag in this case), its reverse complement (A′), a region of cross-homology (B and B′ for this pair) and a fluorochrome each.