In the SELEX method for generating RNA polymers with new functions, what is the practical limit for the complexity of an initial RNA mixture?
Explanation
SELEX (Systematic Evolution of Ligands by Exponential Enrichment) is a powerful in vitro method for isolating RNA or DNA molecules (aptamers) with specific binding or catalytic properties from a large, random pool. The practical upper limit for the diversity of the starting pool is about 10 to the power of 15 unique sequences, which is sufficient to explore the potential functions of relatively short oligonucleotides.
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