DNA shuffling is a technique being utilized for in vitro recombination of a
single gene or pools of homologous genes. The genes are fragmented into ra
ndomly sized pieces, and polymerase chain reaction (PCR) reassembly of full
-length genes front the fragments, via self-priming, yields recombination d
ue to PCR template switching. After these PCR products are screened and the
interesting products sequenced, improved clones are reshuffled to recombin
e useful mutations in additive or synergistic ways, in effect mimicking the
process of natural sexual recombination. Protein can be 'bred' with the ap
propriate individual properties and then their 'progeny' screened for the d
esired combination of traits. DNA shuffling is a powerful tool enabling rap
id and directed evolution of new genes, operons and whole viral genomes.