 The kdr gene in zebra fish encodes for the vascular endothelial growth factor-2 receptor.Mutagenic lesions at this target site was induced using ZFN technique by a group of researchers in US.They suggested that the ZFN technique allows straightforward generation of a targeted allelic series of mutants; it does not rely on the existence of species-specific embryonic stem cell lines and is applicable to other vertebrates, especially those whose embryos are easily available; finally, it is also feasible to achieve targeted knock-ins in zebrafish, therefore it is possible to create human disease models that are heretofore inaccessible.