Furthermore, inflammasome components were measured in three early-onset (rcd1, xlpra2, and erd) and one late-onset (xpra1) canine model of RP, with Nlrp3, Casp1, Asc, Il-1b, Il-1ra, and Il-18 gene expression all upregulated in the most aggressive early-onset model, rcd1, gradually rising from the induction phase of the disease at 3 weeks and peaking in expression during the chronic cell death phase at 16 weeks (23). This evidence concerns the gene IL18 and retinitis pigmentosa 1.