The use of short nucleic acid sequences as “tags” to identify specific biological substances in a sample is known. For example, tags may be used as a method of or as labels for a wide variety of biological and nonbiological materials, see, for example, Dollinger, The Polymerase Chain Reaction pp. 265–274 Mullis et al., editors (Birkhauser, Boston, 1994) or as a method of screening complex chemical libraries. See, for example, Alper, Science, 264: 1399–1401 (1994); and Needels et al. PNAS 90, 10700–10704 (1993). See also U.S. Pat. Nos. 4,359,353, 4,441,943, 5,451,505 and 5,654,413.
There is great necessity for sets of tag sequences which are known to hybridize effectively to their complementary probe sequences with minimal cross-hybridization between the different tag sequences. The presently claimed invention provides sets of tag sequences, tag sequence kits, and methods of using tag sequences which fulfill these requirements.