CRISPR editing demonstrates rs10490924 raised oxidative stress in iPSC-derived retinal cells from patients with <i>ARMS2/HTRA1</i>-related AMD.

Abstract

Genome-wide association studies (GWAS) have identified genetic risk loci for age-related macular degeneration (AMD) on the chromosome 10q26 (Chr10) locus and are tightly linked: the A69S (G>T) rs10490924 single-nucleotide variant (SNV) and the AATAA-rich insertion-deletion (indel, del443/ins54), which are found in the age-related maculopathy susceptibility 2 (<i>ARMS2</i>) gene, and the G512A (G>A) rs11200638 SNV, which is found in the high-temperature requirement A serine peptidase 1 (<i>HTRA1</i>) promoter. The fourth variant is Y402H complement factor H (<i>CFH</i>), which directs <i>CFH</i> signaling. CRISPR manipulation of retinal pigment epithelium (RPE) cells may allow one to isolate the effects of the individual SNV and thus identify SNV-specific effects on cell phenotype. Clustered regularly interspaced short palindromic repeats (CRISPR) editing demonstrates that rs10490924 raised oxidative stress in induced pluripotent stem cell (iPSC)-derived retinal cells from patients with AMD. Sodium phenylbutyrate preferentially reverses the cell death caused by <i>ARMS2</i> rs10490924 but not <i>HTRA1</i> rs11200638. This study serves as a proof of concept for the use of patient-specific iPSCs for functional annotation of tightly linked GWAS to study the etiology of a late-onset disease phenotype. More importantly, we demonstrate that antioxidant administration may be useful for reducing reactive oxidative stress in AMD, a prevalent late-onset neurodegenerative disorder.