Before revision: Also, only a few loci, such as the ROSA26 locus have been characterized well enough where they can be used for conditional gene knock-ins , making combinations of reporter and transgenes in the same locus problematic.
After revision: Also; only a few loci, such as the ROSA26 locus have been characterized well enough where they can be used for conditional gene knock-ins , making combinations of reporter and transgenes in the same locus problematic.