Non-radioactive labeling and detection of nucleic acids. III. Applications of the digoxigenin system.

The digoxigenin-based non-radioactive DNA labeling and detection system was applied in various hybridization protocols using digoxigenin-labeled probes obtained by enzymatic incorporation of Dig-[11]-dUTP. In genomic blots single-copy genes (human tissue-type plasminogen activator, constant part of immunoglobulin kappa light chain) can be detected with only 0.5 to 5 micrograms human DNA depending on the type of probe and the length of the hybridizing region. Due to its high sensitivity and specificity, the digoxigenin system is also appropriate for colony-, plaque-, and in situ hybridizations with metaphase chromosome spreads and fixed cells. Especially in the latter applications it is of great advantage, that with the digoxigenin system any significant background or unspecific side reactions with biological materials are avoided.