Dr. Zein joined the NEI clinical staff in 2009 after completing fellowships at the NEI Ophthalmic Genetics and Visual Function Branch and Children's National Medical Center/The George Washington University in Washington, D.C. In 2003, he completed his residency in ophthalmology at the American University of Beirut in Lebanon. He serves as an ophthalmology advisor and member of the scientific board of multiple patient associations for hereditary disease with ocular manifestations.
Dr. Zein studies hereditary pediatric eye diseases affecting the retina including retinitis pigmentosa, Leber congenital amaurosis, Stargardt disease, and Best disease. Additionally, he investigates systemic hereditary diseases that can affect the eye such as Usher syndrome, Bardet-Biedl syndrome, Alstrom syndrome, Joubert syndrome, WAGR syndrome, and albinism. Dr. Zein's research focuses on the natural history and the pathobiology of these diseases in the hopes of gaining a greater understanding of these conditions. He also concentrates on the psychophysical and electrophysiological studies of ocular function. Dr. Zein has been the principal investigator of the NEI Usher syndrome protocol 05-EI-0096 since 2010.