UGT1A6 and hydrops fetalis: MDR fit identified that combinations of polymorphisms rs9934438 in VKORC1*2, rs2070959 in UGT1A6 and 1801133 in MTHFR*1 genes are the best model of disease prediction status (in our case, whether HF patients were with/without complications) with prediction accuracy of 95.83% (Table 7).