CERKL and Bardet-Biedl syndrome: Several genes connected to retinal degeneration in humans were differentially regulated in degenerating mouse rods, including the downregulation of Fam161a (RP [50]) and the upregulation of Cerkl (RP [45]), Arl6 (Bardet-Biedl syndrome [51]), and Samd7 (RP [52]), a CRX-regulated transcriptional repressor [53] which is essential for rod photoreceptor identity [54] and a paralog of the RP disease gene SAMD11 [55].