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En Face Detection of Nitric Oxide and Superoxide in Endothelial Layer of Intact Arteries
Published on: February 25, 2016
Endothelial nitric oxide synthase polymorphisms and haplotypes in Amerindians
Marcelo R Luizon1, Tatiane C Izidoro-Toledo, Aguinaldo L Simoes
1Department of Pharmacology, Faculty of Medicine of Ribeirao Preto, University of Sao Paulo, Ribeirao Preto, Sao Paulo, Brazil.
DNA and Cell Biology
|May 14, 2009
Summary
Genetic variations in endothelial nitric oxide synthase (eNOS) differ significantly among Amerindians, blacks, and whites. These eNOS gene differences may impact drug responses and cardiovascular health outcomes.
Area of Science:
- Pharmacogenomics
- Human Genetics
- Cardiovascular Research
Background:
- Interethnic variations in endothelial nitric oxide synthase (eNOS) gene polymorphisms can influence nitric oxide (NO) pathways and drug efficacy.
- Previous studies identified disparities between Black and White populations, but data on Amerindian populations were lacking.
Purpose of the Study:
- To investigate the distribution of key eNOS gene polymorphisms and haplotypes in Amerindian populations from the Brazilian Amazon.
- To compare these findings with existing data from Black and White Brazilian populations.
Main Methods:
- Genotyping of three clinically significant eNOS polymorphisms: T(-786)C (promoter), VNTR intron 4, and Glu298Asp (exon 7).
- Analysis of eNOS haplotypes in 170 Amerindians.
- Comparative analysis with published data from Black and White Brazilians.
Main Results:
- Amerindians exhibited significantly lower frequencies of Asp298, C(-786), and 4a eNOS alleles compared to Black and White Brazilians (p < 0.001).
- A predominant eNOS haplotype, comprising the most common alleles, was found in 89% of Amerindians, versus 45% in Blacks and 41% in Whites.
- These results suggest reduced genetic diversity in eNOS polymorphisms among Amerindians.
Conclusions:
- Striking interethnic differences in eNOS allele and haplotype frequencies exist between Amerindians, Blacks, and Whites.
- These genetic disparities may be crucial for interpreting case-control association studies involving eNOS polymorphisms.
- The findings could partially explain variations in cardiovascular drug responses across different ethnic groups.
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