Many valuable mouse models of disease are produced through conditional mutagenesis. This technology often uses the site-specific Cre recombinase in conjunction with loxP recombination target sites to produce controlled mutations in somatic tissues. Konstantinos Anastassiadis, Francis Stewart and colleagues use the site-specific recombinase Dre, which exhibits similar precision and efficiency to Cre, but uses a unique rox recombination target site, to induce specific recombination in mice. Dre recombination was highly specific to rox sites, even in the presence of loxP. The Dre mouse offers an alternative method for the introduction of gene mutations and, in combination with current Cre and FLP techniques, could produce mouse models with multiple conditional mutations.
