BBS1 and Bardet-Biedl syndrome: More recently, Schmid et al. (2013) demonstrated that a combination of modified U1 and U6 snRNAs targeting a substitution of +5G in human cells was more effective than U1 alone to rescue the splicing of the BBS1 gene (Bardet–Biedl Syndrome, a ciliopathy associated with severe vision loss in children).