UGT1A1 and G6PD deficiency: In total, the most common genetic variant was short HO-1 promoter GT-repeat (39.4 %), followed by GA at nt388 in SLCO1B1 (31.1 %), GA at nt211 in UGT1A1 (29.3 %), ABO incompatibility (defined as neonates with A or B blood type born to type O mothers [18]) (16.2 %), alpha thalassemia (5.0 %), G6PD deficiency (3.2 %), and Rh negative (0 %).