Homozygous Dlx5/6-Cre transgenic mice are viable and fertile. Expression of Cre recombinase (Cre) is directed to differentiating and migrating forebrain GABAergic neurons during embryonic development by the I56i and I56ii enhancers from the zebrafish dlx5a/dlx6a intergenic region (with the 5' promoter region of zebrafish dlx6a in place to increase the activity of the intergenic enhancers rather than direct tissue-specific expression). When Dlx5/6-Cre transgenic mice are bred with mice containing a loxP-flanked sequence, Cre-mediated recombination will result in deletion of the floxed sequence in the offspring. These Dlx5/6-Cre transgenic mice may be useful in generating specific deletions of floxed alleles in GABAergic neurons in forebrain and other brain regions.

Luo et al. 2020 Neuron 106:37 Table 1 shows germline recombination in offspring (F2) of Cre;floxed double mutant (F1) mice bred to floxed and/or wildtype mice. The authors also note that in general, the frequency of recombination in Cre;floxed double mutant germline cells appears to be considerably higher than in zygotes produced by breeding Cre mice to floxed mice.
This reports that Dlx5/6-Cre;floxed double mutant females bred to floxed and/or wildtype males produced some offspring with germline deletion of the floxed allele [observed from several cohorts (including up to 85.3% (29/34) of Cre negative offspring)]. As such, for Cre-lox experiments and to avoid/minimize germline deletion of the floxed allele, researchers may consider breeding Dlx5/6-Cre males to floxed females.

If the recombinase activity pattern of this allele is further characterized by the Genetic Resource Science group at The Jackson Laboratory, such findings will be reported on the Mouse Genome Informatics (MGI) Allele Detail entry. For endogenous mouse gene expression, information may also be found searching the MGI Recombinase Activity and MGI Gene Expression + Recombinase Activity Comparison Matrix.