Relationship of endothelial nitric oxide synthase (eNOS) gene polymorphisms with diabetic retinopathy in Caucasians with type 2 diabetes.
BACKGROUND
Nitric oxide synthesized by endothelial nitric oxide synthase (eNOS) plays a key role in the regulation of endothelial function, and controversial results regarding the association of eNOS gene polymorphisms with diabetic complications have been reported.


METHODS
In this case-control study, the relationship of the -786T/C, the VNTR intron 4 a/b and the 894G/T (Glu298Asp) polymorphisms in the eNOS gene with the presence or severity of diabetic retinopathy was analyzed in 630 Caucasian-Brazilians with type 2 diabetes (434 with and 196 without diabetic retinopathy). Genotyping of eNOS polymorphisms was carried out using the PCR or PCR-RFLP method, and haplotype frequencies were estimated using a Bayesian method.


RESULTS
Genotype and allele frequencies in patients with any degree of diabetic retinopathy or proliferative diabetic retinopathy were not significantly different from those of patients without this complication for all eNOS polymorphisms. Likewise, there were no differences in haplotype frequencies among diabetic patients with or without diabetic retinopathy (p values > 0.05 for all comparisons).


CONCLUSIONS
Our findings do not support the hypothesis that the -786T/C, the VNTR intron 4 a/b and the 894G/T (Glu298Asp) polymorphisms in the eNOS gene play a role in the pathogenesis of diabetic retinopathy in type 2 diabetes.
Research Center in Medical Sciences, Universidade Luterana do Brasil, Canoas, Brazil. kgsantos2010@gmail.com
Kátia G
KG
Santos
Daisy
D
Crispim
Luís H
LH
Canani
Paula T
PT
Ferrugem
Jorge L
JL
Gross
Israel
I
Roisenberg
D001938:Brazil; D016022:Case-Control Studies; D003924:Diabetes Mellitus, Type 2 / Q000235:genetics*; D003930:Diabetic Retinopathy / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D060005:Genotyping Techniques; D006801:Humans; D007438:Introns / Q000235:genetics; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats; D052250:Nitric Oxide Synthase Type III / Q000235:genetics*; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D020641:Polymorphism, Single Nucleotide; D012189:Retrospective Studies; D012307:Risk Factors; D044465:White People / Q000235:genetics*
C496314:NOS3 protein, human; D052250:Nitric Oxide Synthase Type III