• eNOS Gene Intron 4 VNTR;
  • eNOS Gene Exon 7-G894T;
  • Polymorphisms;
  • Erectile Dysfunction


Introduction.  The associations between the gene polymorphisms and erectile dysfunction (ED) are limited.

Aim.  To examine a potential association between variable number of tandem repeats (intron 4 VNTR), G894T polymorphisms, and ED in Turkish men.

Methods.  Sixty-four men with ED and 82 healthy men as a control group were included in the study. The patients were evaluated by medical history, International Index of Erectile Function (IIEF), serum glucose, and lipid profiles. VNTR and G894T polymorphism were assessed by isolated DNA blood samples obtained from the patient group with ED and controls.

Main Outcome Measures.  Assesment of IIEF and VNTR and G894T polymorphism in the isolated DNA blood samples.

Results.  Genotype distributions of endothelial nitric oxide syntase (eNOS) gene intron 4 VNTR polymorphisms in the patient group were similar to those in the healthy group (P > 0.05). The frequency of the eNOS gene intron 4 genotype was found as bb: 55 (67.1%), ab: 26 (31.7%), and aa: 1 (1.2%) in the controls and bb: 43 (67.2%), ab: 19 (29.7%), and aa: 2 (3.1%) in the patient group. The frequency of the G894T was found as gg: 61 (74.4%), gt: 21 (25.6%), and tt: 0 (0.0%) in the controls and gg: 32 (50.0%), gt: 27 (42.1%), and tt: 5 (7.8%) in the patient group (P = 0.002). The frequencies of the “t” allele were 21 (12.8%) in the control group and 37 (28.9%) in the patient group (P = 0.001). Logistic regression analysis showed that G894T polymorphism was an independent risk factor for ED.

Conclusions.  We found significant differences in allelic and genotypic frequencies between patients and controls for the G894T eNOS polymorphisms. The presence of 894T allele in carriers increased the risk of ED. No association was found between VNTR polymorphism and in patients with ED. Erol B, Bozdogan G, Akduman B, Dursun A, Bozdogan S, Onem K, and Mungan A. eNOS gene intron 4 VNTR and exon 7-G894T polymorphisms in Turkish men with erectile dysfunction: A case control study. J Sex Med 2009;6:1423–1429.