Transgene expression is seen as fluorescence under exposure to a 488 nm light source. In transgenic mice the reporter may be detected as early as ~E2.75, as morula stage embryos begin to compact. Expression of GFP is spatiotemporally ubiquitous, though levels differ between different lineages (e.g., expression is slightly higher in the heart).

No discernible phenotype, other than green fluorescence, has been observed in any mice carrying this transgene.