An Analysis On The Association Of GT-repeat Polymorphism In The 3'-flanking Region Of Angiotensinogen Gene With Essential Hypertension In Kazakans

Objective To investigate the relationship between GT-repeat polymorphism in the 3'-flanking region of AGT gene and essential hypertension (EH) in Kazakans. Methods This population-based case-control study recruited 170 subjects (89 hypertensives and 81 normotensives) in Kazakans. GT-repeat polymorphisms of AGT were determined in DNA extracted from peripheral blood leucocytes by polymerase chain reaction (PCR), capillary electrophoresis,DNA sequencing and Genetic Profiler automatic analysis software to identify the distrubution on allele frequencies of 3'-flanking GT-repeat in essential hypertensive and normosive groups. Results There were 13 alleles in all subjects. The allele frequencies were 0.003 to 0.197, and allele A6 was more frequent in Kazakans, following A3 and A4. The heterozygosity of GT repeat locus was 0.862; the polymorphic information content (PIC) is 0.847. Allele frequencies of GT-repeat polymorphisms in the 3'-flanking region of AGT gene in Kazakans are in good agreement with Hardy-Weinberg equilibrium. In essential hypertensive group, Allele frequencies (A1-A13) were as follows: 1(0.56%), 0(0), 31(17.4%), 29(16.29%), 12(6.7%), 35(19.6%), 12(6.7%), 15(8.4%), 5(2.8%), 5(2.8%), 28(15.7%), 4(2.2%), 1(0.56%), respectively; While in normotensive group: 0(0), 3(1.6%), 28(17.3%), 25(15.4%), 15(9.3%), 32(19.8%), 7(4.3%), 14(8.6%), 2(1.2%), 6(3.7%), 25(15.4%), 4(2.5%), 1(0.62%), respectively. There was no significant diffeience between two groups (X2=1.773, p>0.05). Conclusion The results suggested that GT repeat polymorphisms of AGT gene be not in association with EH in Kazakans, which implicated that AGT gene may not be in linkage disequilibrium with the pathogenetic genes of EH.