Combinatorially-synthesized deoxyribonucleic acid (DNA) oligonucleotides
attached to encoded beads that are hybridized to amplified and labeled
genomic DNA or ribonucleic acid (RNA) are analyzed using a flow imaging
system. Oligonucleotides and corresponding reporters are bound to the
surfaces of a plurality of small beads such that different beads bear
different oligo sequences. Each bead bears a unique optical signature
comprising a predefined number of unique reporters, where each reporter
comprises a predefined combination of different fluorochromes. The
composite spectral signature in turn identifies the unique nucleotide
sequence of its attached oligo chains. This optical signature is rapidly
decoded using an imaging system to discriminate the different reporters
attached to each bead in a flow in regard to color and spatial position
on the bead.