Stephen Tsang is the László Bitó Associate Professor in Ophthalmology, Pathology & Cell Biology at Columbia University and an attending ophthalmologist at New York-Presbyterian Hospital. He has been culturing embryonic stem (ES) cells since 1992. In 1995 Tsang created the first mouse model for a recessive form of retinitis pigmentosa (RP) by applying genome engineering to ES cell technology. As the director of an international referral center for inherited retinal degenerations, Dr. Tsang cares for a specific subgroup of patients that are most appropriately aligned with precision medicine. He has co-authored over 147 peer-reviewed publications and is the editor of a book on the uses of genome engineering in the field of stem cell research Stem Cell Biology and Regenerative Medicine in Ophthalmology, Springer Press, NY. Dr. Tsang is a standing member of the DPVS study section, American Society for Clinical Investigation, Macular Society, and American Ophthalmological Society.