As described later, this SIRT6 function is connected to the concept of the photoreceptor–RPE energy ecosystem and therefore has implications in retinal degenerative diseases such as retinitis pigmentosa (RP) and age-related macular degeneration (AMD) (Kanow et al., 2017; Leveillard et al., 2019; Hurley, 2021). Here, SIRT6 is linked to retinitis pigmentosa 1.