COMT and retinopathy of prematurity: Finally, some studies indicated that the interaction effect between CU and CT on PLE [37, 50, 55-57, 60, 61] and ROP [41] is further complexified by additional factors that would have a role in conferring a greater risk, including catechol-O-methyltransferase (COMT) gene [60, 61], urbanicity [50, 55, 56], SLEs [41], threat-induced cognitive biases [57], cognitive alteration [56], and cognitive fusion [37].