The potential of gene delivery systems to treat eye disease stemming from abnormal blood vessel growth is reported by Itay Chowers in the British Journal of Ophthalmology (August issue). Induced retinopathy of prematurity (a disease increasing as a result of the rising numbers of surviving premature babies), is a leading cause of blindness and defective vision in children. The gene-delivery capabilities of four different viruses — adenovirus, bovine smallpox virus, herpes virus and the murine leukaemia virus — were tested in 18-day-old rats. Adenovirus was the most effective gene-transfer vector, with vaccinia coming in a close second. The murine leukaemia virus failed to deliver genes producing a functional product. DM