Article

Intron 4 a/b polymorphism of the endothelial nitric oxide synthase gene is associated with both type 1 and type 2 diabetes in a genetically homogeneous population.

Department of Paediatrics, University of Crete, Heraklion, Crete, Greece.
Human Immunology (impact factor: 2.84). 69(4-5):279-83. DOI:10.1016/j.humimm.2008.03.001 pp.279-83
Source: PubMed

ABSTRACT Current classifications of diabetes distinguish between type 1 diabetes (T1D) and type 2 diabetes (T2D), however recent evidence highlights overlap between T1D and T2D. Earlier studies have suggested altered nitric oxide (NO) metabolism in both T1D and T2D. In the present case-control study, we investigated whether the endothelial NO synthase gene intron 4 a/b polymorphism is associated with T1D and T2D in the island of Crete, a well-defined area with genetically homogeneous population. Mutated allele "a" was more common in individuals with both T1D and T2D than in controls (odds ratio [OR] = 1.71, 95% confidence interval [CI] = 1.06-2.77, p = 0.013; and OR = 1.50, 95% CI = 0.930-2.42, p = 0.047, respectively). Mutated genotype (a/a or a/b) was more common in individuals with T1D than in nondiabetic individuals (OR = 1.93, 95% CI = 1.12-3.32, p = 0.008); this increased frequency was also observed for T2D, although not at a significant level (OR = 1.38, 95% CI = 0.802-2.37). No difference was found in the frequency of mutated allele a or mutated genotype (a/a or a/b) between T1D and T2D populations. In conclusion, our results indicate that allele a of the intron 4 endothelial NO synthase gene is associated with susceptibility to both T1D and T2D and may represent a common genetic factor for diabetes.

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    BMC Medical Genetics 09/2009; 10:79. · 2.33 Impact Factor
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Keywords

95% confidence interval [CI]
 
allele
 
common
 
common genetic factor
 
Current classifications
 
genetically homogeneous population
 
increased frequency
 
mutated allele
 
mutated genotype
 
nitric oxide
 
nondiabetic individuals
 
odds ratio [OR]
 
overlap
 
recent evidence
 
synthase gene
 
synthase gene intron 4 a/b polymorphism
 
T2D populations
 
type 1 diabetes
 
type 2 diabetes
 
well-defined area