PURPOSE: The purpose of the present study was to test whether a lentiviral vector encoding the marker lacZ gene under the control of the human CMV promoter would stably infect a significant number of RPE cells in the vitiligo mouse. This mouse harbors a mutation in the microphthalmia gene in RPE cells that leads to slow progressive photoreceptor cell degeneration. METHODS: Concentrated lentiviral vector HR'CMVlacZ was injected intravitreally into newborn vitiligo mice. Mice were sacrificed at various time points up to two months post-injection and eyes were processed histochemically to detect lacZ expression. RESULTS: The lentiviral vector infected predominantly the RPE and resulted in lacZ expression in numerous RPE cells at all times analyzed. CONCLUSIONS: LacZ expression in vitiligo RPE cells appeared to be stable for a period of at least two months. These results raise the possibility of using a similar lentiviral vector for introduction of a correct copy of the microphthalmia cDNA into the RPE that may ultimately rescue photoreceptor cells in this mutant mouse.