Association of eNOS gene polymorphism (Glu298Asp) with psoriasis

Association of endothelial nitric oxide synthase Glu298Asp gene polymorphism in psoriasis cases with hypertension

BACKGROUND AND OBJECTIVES

Psoriasis is a common autoimmune-mediated chronic, inflammatory skin disease. Although, the molecular mechanism is not completely understood, psoriasis is caused by genetic and non-genetic parameters. The current study aimed (1) to define genotype and allele frequency of endothelial nitric oxide synthase (eNOS Glu298Asp) gene polymorphism in hypertensive and/or non-hypertensive psoriatic patients (2) to investigate the possible relationship between the eNOS Glu298Asp polymorphism and the risk of hypertension among psoriatic patients in the Turkish population.

DESIGN AND SETTINGS

This cross-sectional, case-control study was performed between March 2010 and November 2012 at the University hospital in Çanakkale, Turkey Patients and Methods: Gene profiles of 75 psoriatic patients (21 hypertensive and 54 normotensive pa.tients) and 55 healthy (normotensive and non-psoriatic) volunteers were compared. Peripheral blood-EDTA samples were used for total genomic DNA isolation and genotyping. Target eNOS gene was genotyped for patients and control groups by real-time PCR melting-curve analysis system (LightCycler 2.0,Roche, Germany, and results were compared statistically.

RESULTS

An increased T allele frequency in eNOS Glu298Asp single-nucleotide polymorphism (SNP) was determined in psoriatic patients when compared with normotensive non-psoriatic healthy volunteers (OR 2.3, CI 1.14-3.99), (P=.017). The T allele frequency was also found to be increased in hypertensive psoriatic patients when compared with healthy volunteers (4.83-fold increased, 95% CI 1.62-14.43 ([P=.003]) and normotensive psoriatic patients (3.03-fold increased, 95% CI 1.03-8.94 [P=.041]), respectively.

CONCLUSION

The current preliminary results suggested that there was a correlation between eNOS Glu298Asp polymorphism and hypertension among psoriatic patients in the Turkish population. The T allele frequency of eNOS Glu298Asp SNP was different in hypertensive psoriatic patients, and the difference was statistically significant when compared with the normotensive psoriatic patients and healthy controls. These results need to be confirmed by large-scale studies.

Influence of endothelial nitric oxide synthase polymorphisms in psoriasis risk

Nitric oxide (NO) is a potent regulator of keratinocyte growth and differentiation that has been implicated in the pathogenesis of psoriasis (Ps). The NOS3 -786 T/C (SNP id rs2070744; http://www.ensembl.org ), intron 4 variable number tandem repeat (VNTR), and Glu298Asp (SNP id rs1799983) polymorphisms, have been associated with differences in NO plasma concentrations and with the risk of hypertension (HT) and ischemic cardiac disease. The aim of this study was to determine whether the above-mentioned NOS3 variants contributed to the risk of Ps, and were associated with the risk for HT and CAD in these patients. A total of 368 patients with chronic plaque Ps and 400 healthy controls were genotyped for the NOS3 -786 T/C, intron 4 VNTR, and Glu298Asp polymorphisms. Carriers of the -786 C allele were significantly more frequent among the patients (p < 0.001). Carriers of the 4-repeats allele (45 + 44 genotypes) were also more frequent a (p < 0.001). No significant difference was found for the Glu298Asp polymorphism. None of the NOS3 variants was associated with Ht and CAD in our population. In conclusion, NOS3 gene polymorphism would be risk factors for developing Ps.