Abstract
Purpose:
The aim of the study was the evaluation of the polymorphism of eNOS gene G895T and T786C in patients with normal tension glaucoma (NTG) and high tension glaucoma (HTG) and the evaluation of peripheral blood vessels status in NTG patients.
Methods:
The studied group constituted 146 glaucoma patients treated in Medical University, Lublin, Poland. Patients were divided into 2 groups: NTG (94 patients) and HTG (49 patients). A capillaroscopic examination was performed in 35 NTG patients with videocapillaroscope VideoCap 3,0 D1. DNA was isolated from full blood using commercial kits (Qiagen). Using PCR reaction 7th exon fragment was amplified and then restricted using Eco24l enzyme to assess polymorphic variants of G894T. RT-PCR reaction was applied to amplify promotor site of eNOS gene including SNP site T786C (TaqMan).
Results:
Polymorphism G894T was checked in 139 patients: 93 NTG and 46 HTG. In NTG group GG genotype was present in 18 cases (19%), GT in 61 patients (66%) and TT in 14 (15%). T allel were detected in 75 patients (81%). In HTG group GG variant was observed in 15 patients (33%), GT in 25(54%) and TT in 6 (13%). T allel were detected in 31 patients (67%). There were no statistically significant differences in gene variants between glaucoma groups (p>0,005). The polymorphism T786C was evaluated in 146 patients: 97 NTG and 49 HTG. In NTG group TT genotype was present in 35 cases (36%), TC in 51 patients (53%) and CC in 11(11%). C allel were detected in 62 patients (64%). In HTG group TT variant was observed in 21 patients (43%), TC in 24 ( 49%) and CC in 4 cases (8%). C allel were detected in 28 patients (57%).C allel were detected most frequently in NTG women group (15,6%) compared with NTG men group (3%) and HTG women group (8,8%). There were no statistically significant differences ( p>0,005) . In capillaroscopic examination the NTG patients presented the following disturbances: megacapilaries or dilatated capillaries (44.4%), ramified/bushy (18.9%), coiled (17.1%). In 4 (11.4%) patients the capillaroscopic view mimicked sclerodermia.
Conclusions:
There is no difference in genotype frequencies of the endothelial nitric oxide synthase G894T and T786C polymorphisms in NTG and HTG. Endotelial nitric oxide synthase G894T and T786C polymorphisms do not influence the capillary system in NTG patients.
Keywords: 533 gene/expression