Polymorphisms of Angiotensin‐converting Enzyme, Angiotensinogen, Angiotensin Ii Type 1 and Type 2 Receptors and Endothelial Nitric Oxide Synthase in Turkish Renal Transplant Recipients: A Preliminary Study

Many researchers are now focusing on ways in which the renin‐angiotensin system (RAS) and RAS gene polymorphism affect progressive renal damage, hypertension, cardiac complications, and renal allograft function. In this study, we investigated the frequency of polymorphism in the genes for angiotensin‐converting enzyme (ACE), angiotensinogen (AGT), angiotensin II type 1 and 2 receptors (AT1 and AT2), and endothelial nitric oxide synthase (ec‐NOS) in Turkish renal transplant recipients. Angiotensin‐converting enzyme insertion/deletion (I/D) polymorphism was assessed in 125 patients. M235T polymorphism of the angiotensinogen gene, 1166 A/C polymorphism of the AT1 receptor gene, and 3123C/A polymorphism of the AT2 receptor gene, and intron 4 VNTR polymorphism in the ec‐NOS gene were assessed in 40 of the patients. The latter list was also investigated in 50 healthy controls from the general Turkish population. DD/ID/II genotypes of the ACE gene were detected in 56%, 34%, and 10% of the kidney recipient group, respectively. In the 40 recipients who were tested for the other polymorphisms, the corresponding figures for the AGT TT/TM/MM genotypes were 0%, 82.5%, and 17.5%, respectively; for the AT1 CC/CA/AA genotypes were 0%, 2.5%, and 97.5%, respectively; for the AT2 AA/CA/CC genotypes were 0%, 0%, and 100%, respectively; and for the ec‐NOS intron 4 aa/ab/bb genotypes were 0%, 12%, and 88%, respectively. The results revealed that Turkish renal transplant recipients exhibit a wide‐range of RAS gene and ec‐NOS polymorphisms.