Atherosclerosis: analysis of the eNOS (T786C) gene polymorphism.

The coronary arteriosclerotic disease is the most common cardiovascular disease. Atherosclerosis affects large- and medium-sized arteries leading to severe thrombosis or artery stenosis that could evolve to myocardial infarction, ischemic stroke, ischemic injury of kidneys and intestines, and several other life-threatening clinical manifestations. Nitric oxide has been shown to be a promising therapeutic agent against cardiovascular diseases. The eNOS gene assumes several important functions, including regulation of vascular tone and regional blood flow, the suppression of vascular smooth muscle cell proliferation, and modulation of leukocyte-endothelium interactions. The T786C polymorphism is an important point mutation, where thymine is changed to cytosine. T786C significantly reduces the activity of the eNOS promoter gene. Two hundred and ninety-seven peripheral blood samples were collected from patients with the previous diagnosis of atherosclerotic disease based on clinical examination and confirmed by imaging methods. Results were compared using the chi-square test and the G-test. In the present study, the TC genotype was more frequent in both case and control groups with no statistically significant difference. Comparing the relation TC/TT and CC genotypes in the case and control groups, there was no statistically significant difference. No significant difference was found when genotypes were analyzed regarding gender and smoking. Our results suggest a strong tendency of the T allele, in single or double dose, to be associated with atherosclerosis that was not confirmed by the scientific data.

Analysis of the prevalence of polymorphisms in the glutathione S transferase gene (GST) in cataract patients from Goiânia.

The aim of this study was to determine the prevalence of polymorphisms in the glutathione S-transferase genes GSTM1 and GSTT1 in patients with lens opacity (cataract). Peripheral blood samples were obtained from male and female patients (N = 23) with cataract. The GSTM1 and GSTT1 polymorphic regions were amplified by polymerase chain reaction, and the amplification products were electrophoresed on a 2% agarose gel. The obtained bands were by staining with ethidium bromide. The results were compared by a chi-square test using the BioEstat software (v.5.0). The frequencies of the GSTM1- and GSTT1-null genotypes were higher than those of the GSTM1- and GSTT1-present genotypes. The frequency of GSTT1-null genotypes was approximately 1.7 times higher than that of GSTM1, which was a statistically significant difference (P = 0.0019). Although a consensus remains to be reached on the correlation between genetic polymorphisms in GSTs and cataract susceptibility, the observations from most scientific studies are similar to those reported in this study. Thus, we conclude that the absence of these genes, particularly GSTT1, is correlated with the development of lens opacity.