Effects of the angiotensinogen gene M235T and A(-6)G variants on blood pressure and other vascular risk factors in a Spanish population

Angiotensinogen (AGT) gene polymorphism has shown significant differences i n the allelic frequencies between hypertensive and normotensive subjects, T his allele frequency varies among ethnic groups. There are still some contr oversies related to the 235T-variant as a marker for essential hypertension , As part of an extensive case-control study carried out in a Spanish popul ation, we selected the 237 subjects with a diagnosis of essential hypertens ion according to the established criteria. A group of 242 normotensives mat ched for age and gender was used as control, Smoking habits, a previous dia betes and hypertension medical history, body mass index (BMI) and blood pre ssure (BP) values were recorded, Glucose, plasma creatinine, lipid profile with Lp(a), homocysteine and microalbuminuria were measured, Angiotensinoge n M235T-gene polymorphism was determined by polymerase chain reaction (PCR) from genomic DNA, A(-6)G polymorphism was determined by mutagenically sepa rated PCR (MS-PCR), BP values, BMI and microalbuminuria were significantly higher in hypertensive subjects; 31.6% of hypertensives and 40.1% normotens ives were active smokers. M235T-genotype frequencies were not different In the hypertensive and normotensive population. Similarly, homocigotic AA pre dominate in the hypertensives but without statistical significance, The ass ociation of 235T-genotype or the changes in the promoter activity due to A( -6) substitution with essential hypertension was not confirmed in the multi variate regression analyses. Only a previous family history of hypertension and BMI were significantly associated with hypertension.