A In individuals from Kingdom of Saudi Arabia (KSA), variants in RP1 (~20%), TULP1 (~20%), EYS (~8%), CRB1 (~7%), MERTK (~7%), and RLBP1 (~5%) account for two-thirds of the known variants. B In North Africa, the main identified genes defects were harbored in: MERTK (18%), RLBP1 (18%), RPE65 (8%), and PDE6B (8%), accounting for half of the solved cases.