Patent ID: 7393665

Claim:
A method of generating a mixture of polynucleotides tagged with different oligonucleotide tags, the method comprising the steps of: (a) providing: (i) a mutually discriminable set containing a plurality of different words; and (ii) a plurality of different polynucleotide samples; (b) separately attaching one or more of the different words to all of the polynucleotides from each sample in a first subset of the plurality of different polynucleotide samples to form tag-polynucleotide conjugates, wherein the polyuncleotides in each sample of the first subset are thus tagged with a unique word or unique order of words; (c) repeating step (b) for each subsequent subset of the plurality of different polynucleotide samples to form a base tier of tag-polynucleotide conjugates and recording which unique word or unique order of words is attached to the polynucleotides from each different polynucleotide sample in the base tier; (d) combining tag-polynucleotide conjugates in each subset of the base tier to form a plurality of combined submixtures wherein the tag-polynucleotide conjugates from any particular polynucleotide sample in each combined submixture have an oligonucleotide tag that is different from that of any other tag-polynucleotide conjugates in the same combined submixture; (e) attaching a different word to each different submixture of step (d) to form another tier of submixtures of tag-polynucleotide conjugates and recording which word is attached to each tag-polynucleotide conjugate in each submixture; and (f) repeating steps (d) and (e) for the plurality of combined submixtures until only a single combined submixture is produced in step (d), thereby generating a mixture of polynucleotides wherein polynucleotides from each of the plurality of polynucleotide samples is tagged with a different oligonucleotide tag.