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Endothelial NO synthase gene polymorphisms and hypertension: a meta-analysis
Elias Zintzaras1, Georgios Kitsios, Ioannis Stefanidis
1Department of Biomathematics, University of Thessaly School of Medicine, Papakyriazi 22, 41222 Larissa, Greece. zintza@med.uth.gr
Hypertension (Dallas, Tex. : 1979)
|August 31, 2006
Summary
The 4b/a polymorphism in the endothelial nitric oxide synthase gene is linked to a reduced risk of hypertension. This association was significant in whites, but not in East Asians or blacks.
Area of Science:
- Genetics
- Cardiovascular Disease Research
- Molecular Biology
Background:
- Endothelial nitric oxide synthase (eNOS) gene polymorphisms have been investigated for their association with hypertension.
- Previous studies reported contradictory or inconclusive results regarding this link.
- A comprehensive meta-analysis is needed to clarify the role of eNOS polymorphisms in hypertension risk.
Purpose of the Study:
- To conduct a meta-analysis of genetic association studies to examine the relationship between hypertension and specific eNOS gene polymorphisms (G894T, 4a/b, T786C, G23T).
- To explore subgroup differences by ethnicity and identify potential sources of heterogeneity and bias.
Main Methods:
- Meta-analysis of 35 genetic association studies.
- Inclusion of genotype data from 7779/10498, 2216/3222, 2491/3913, and 833/587 cases/controls for G894T, 4b/a, T786C, and G23T polymorphisms, respectively.
- Subgroup analyses based on ethnicity (whites, East Asians, blacks) and genetic models (recessive, dominant).
Main Results:
- The 4b/a polymorphism showed a significant association with a 15% decreased risk of hypertension (OR: 0.85; 95% CI: 0.74 to 0.98).
- This protective effect of the 4b allele was significant in whites under a recessive genetic model (OR: 0.76; 95% CI: 0.62 to 0.92).
- No significant associations were found for G894T, T786C, and G23T polymorphisms, nor for the 4b/a polymorphism in East Asians and blacks.
Conclusions:
- Evidence supports an association between the 4b/a polymorphism of the endothelial nitric oxide synthase gene and hypertension, particularly in white populations.
- The G894T, T786C, and G23T polymorphisms do not appear to be significantly associated with hypertension.
- Further research investigating combinations of eNOS polymorphisms may provide deeper insights into hypertension genetics.
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