Given these antecedents and the enrichment of HtrA1 risk variants in a subset of AMD subjects (Supplementary Table S1), we were thus curious whether in vitro surrogates (Suner et al., 2004; Supanji et al., 2013) for these stressors induce HtrA1 expression in RPE. This evidence concerns the gene HTRA1 and age-related macular degeneration.