Aim:
The main aim of the present paper is to investigate allele frequencies of rs1799983 polymorphism eNOS genes and to determine association between rs1799983 polymorphism of eNOS gene and essential hypertension in Iraqi hypertensive patients

Material and methods:
This is an observational cross sectional descriptive single center study. ninety hypertensive patients were recruited by specialist cardiologist and conducted at AL-Diwaniyah teaching hospital and department of pharmacology and therapeutics, college of medicine, university of Al-Qadisiyah, Iraq. DNA samples were genotyped by PCR-tetra-arm method. NO level was measured by using ELISA kit.

Results:
Regarding rs1799983 the most frequent allele was G (73%) and the most frequent genotype was GG (55%). Our results indicate lack of substantial link between genotype frequencies of rs1799983 polymorphism and NO level (p=0.88) and thereby there is no statistically significant effect on SBP and DBP (p = 0.051).

Conclusions:
our study demonstrated lack of significant association between this polymorphism and essential hypertension in Iraqi hypertensive patients.