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Molecular variant M235T of the angiotensinogen gene is associated with essential hypertension in Taiwanese

Objective To examine the association of the molecular variants of the angiotensinogen (AGT) gene with essential hypertension in Taiwanese. Methods We conducted a case-control study concerning 151 subjects, 102 hypertensives and 49 normotensives. We created a rapid mini-sequencing method based on dye-terminator cycle sequencing to simultaneously detect the M235T and T174M variants of the AGT gene for each subject. Results The genotype and allele distribution of the M235T variant differed significantly in hypertensives and normotensives (χ2 = 11.106, P = 0.004 and χ2 = 6.453, P = 0.011, respectively), whereas those of the T174M variant did not differ (χ2 = 0.004, P = 0.998 and χ2 = 0.032, P = 0.858, respectively). The odds ratio for hypertension was 3.64 (95% confidence interval 1.56–8.49) for subjects with the C/C genotype of the M235T variant compared with other genotypes or 2.87 (95% confidence interval 1.76–4.68) for those carrying allele C versus those carrying allele T. Conclusion The molecular variant M235T, but not T174M, of the AGT gene is associated significantly with essential hypertension in this Taiwanese population. The genotype C/C or allele C is a risk factor for hypertension. The underlying mechanism of this association needs to be elucidated further.

Lack of association of the angiotensin converting enzyme gene polymorphism with essential hypertension in a chinese population

To examine the association between insertion/deletion (I/D) polymorphism of the angiotensin converting enzyme (ACE) gene and essential hypertension in a Chinese population, a case-control study was conducted using 157 hypertensive and 115 normotensive subjects. The I/D polymorphism of the ACE gene was identified by polymerase chain reaction. Plasma ACE activity was determined using spectrophotometry. The difference of allele frequencies between normotensives and hypertensives was statistically significant (chi 2 = 4.467, P = .035), while the genotype distribution was not different between normotensive and hypertensive subjects (chi 2 = 3.954, P = .138). Plasma ACE activity was highest in the DD genotype, followed by the ID genotype, and the lowest in the II genotype (P = .0001 in normotensives and P = .163 in hypertensives, respectively). Thus, we conclude that the ACE gene polymorphism is not associated with essential hypertension in this Chinese population, but plasma ACE activity is genetically determined in the normotensive Chinese.

Expression Pattern in a Modified Equalized Kidney cDNA Library of Hypertensive Rat

Background: Genes with important functions and rarely expressed would probably more easily be cloned from a modified equalized kidney cDNA library for further investigation. Methods: A kidney cDNA library of a spontaneously hypertensive rat was synthesized by a modified equalization method. Inserts of random clones were amplified by PCR and sequenced. Sequences were compared against a nonredundant database in GenBank. The cDNA profile was compared with an expression profile of a mouse renal proximal tubule cDNA library. Seven clones were analyzed by Northern blot analysis. The cDNA ends of two novel genes were amplified by PCR, sequenced and analyzed. Results: 336 cDNA clones were analyzed and grouped into 323 species of transcript with 77 species similar to previously reported genes. Northern blot analysis identified one kidney-specific, one rarely expressed and lung-specific, and another relatively testis-specific gene. Two novel genes were cloned. One was 4.1 kb in length and encoded a 390-amino acid zinc-finger protein. Another was 2.5 kb and encoded a 474-amino acid protein of unknown function. Compared with the expression profile of a mouse renal proximal tubule cDNA library, this kidney library had a lower proportion of ribosomal genes and had a greater proportion of genes for signal transduction and DNA or RNA binding. Conclusions: Rare or novel genes could be more easily isolated from this library for molecular study of hypertension and renal pathophysiology.