INS and late-onset retinal degeneration: Late-onset retinal degeneration has been linked to mutations in the C1QTNF5 gene.[45,46] It belongs to the C1q/TNF-related protein (CTRP) family, a family of genes that link immunity to metabolism by exerting anti-inflammatory and insulin-sensitizing effects.[47] Surprisingly, C1q/TNF-related protein 3 (CTRP3) in the same family might serve as a novel biomarker for DR severity.[48]