Research results published in the journal Investigative Ophthalmology & Visual Science (doi:10.1167/iovs.13-11673) have demonstrated that sub-retinal injection of the wild-type Bbs1 gene in a murine model of Bardet-Biedl syndrome (BBS) results in partial rescue of the BBSome formation, rhodopsin localization and a trend towards improved ERG function. However, the study, conducted by Dr. Seongjin Seo and colleagues at the University of Iowa’s Department of Ophthalmology, suggested that gene replacement in such retinal ciliopathies may be more complex than in other retinal disorders, potentially due to toxicity arising from an excess of BBS1 protein.