TFAP2B and Patent ductus arteriosus: SNPs in TFAP2B, tumor necrosis factor (TNF) receptor associated factor 1 (TRAF1),126 angiotensin II receptor type 1 (AGTR1),127 elastin,128 methylenetetrahydrofolate reductase (MTHFR),129 and multiple other genes predispose infants to PDA.