The prevalence of angiotensinogen polymorphism M235T in the group of patients with essential hyperten­sion from the Republic of Macedonia was 55.0%. These results are consistent with those described in European studies, showing a prevalence of 30-60% in patients with essential hypertension [4]. The prevalence of M235T in the control group of healthy volunteers from the Republic of Macedonia is 32.5%. Large studies on healthy individ­uals of different racial and ethnic backgrounds report a different prevalence. This is consistent with the hypothesis which postulates that M235T appeared for the first time on the Pleistocene savannas of Continental Africa, where it showed evolutionary and selective advantages in low salt level surroundings [8]. The question of the different prevalence of this polymorphism in different populations from Europe has not yet been elucidated. A large metha-analysis of European studies concluded that healthy indi­viduals analyzed from the control group are younger and thinner than patients with essential hypertension. Thus, there is a possibility that they will probably develop hy­pertension as they grow older or gain weight [9].

We found a statistically significant difference in prev­alence of M235T (p <0.04). Our results show an associa­tion of angiotensinogen polymorphism M235T and essen­tial hypertension, which may suggest that the role of M235T is a factor in ethiopatogenesis of essential hyper­tension. These results are consistent with those reported in a great number of studies [4,10-17]. However, there are other studies that failed to confirm this association [18-22]. The contradiction of reported data on association of M235T polymorphism and essential hypertension is proba­bly due to inaccurate inclusion criteria being applied in these studies, which emphasizes the necessity of strict definition of the group of patients included, regarding family history, level of BP, anti-hypertensive treatment, ethnic background and acquired risk factors.

We investigated whether the clinical characteristics of hypertensive patients (age, sex, anti-hypertensive therapy and acquired risk factors) differed according to the M235T polymorphism carried, in an attempt to identify a possible subset of patients with a higher genetic risk. The difference of these factors according to the M235T that we found was not statistically significant, which is proba­bly due to the small group of samples tested. In conclu­sion, our results suggest that the M235T polymorphism is a risk factor for essential hypertension in patients from the Republic of Macedonia.