title: VNTR polymorphism in intron 4 of the eNOS gene and the risk of ischemic stroke in a South Indian population.
abstract: Ischemic stroke is a leading cause of death throughout the world. An increasing number of studies have suggested that genetic factors are important in the stroke risk. The aim of our study was to investigate whether the Variable Number of Tandem Repeats (VNTR) polymorphism in intron 4 of the endothelial nitric oxide synthase (eNOS) gene is associated with ischemic stroke in a South Indian population. 357 patients and 283 controls were enrolled in this case-control study. The ischemic stroke patients were classified according to TOAST classification. The eNOS gene polymorphism was determined by polymerase chain reaction-polyacrylamide gel electrophoresis. The genotypes were confirmed by sequencing the PCR products. There were significant differences in the genotype and allele frequencies of eNOS polymorphism between the patients with ischemic stroke and healthy controls (p=0.000). Multiple logistic regression analysis with forward stepwise selection using the potential confounders (sex, age, diabetes, hypertension, smoking and alcoholism) and eNOS gene variant revealed that the VNTR polymorphism in intron 4 of the eNOS gene is significantly [adjusted odds ratio=6.23, 95%CI (4.30-9.29), p=0.000] associated with ischemic stroke in the South Indian population from Andhra Pradesh. We did not find significant association of this polymorphism with any specific stroke subtype. Further hypertensives bearing 4a allele in high frequency are more predisposed to stroke.
authors.affiliation: Institute of Genetics and Hospital for Genetic Diseases, Osmania University, Begumpet, Hyderabad 500016, India. anjanadurani@yahoo.co.in
authors.forename: Anjana
authors.initials: A
authors.lastname: Munshi
authors.forename: K
authors.initials: K
authors.lastname: Rajeshwar
authors.forename: Subhash
authors.initials: S
authors.lastname: Kaul
authors.forename: E
authors.initials: E
authors.lastname: Chandana
authors.forename: Gowhar
authors.initials: G
authors.lastname: Shafi
authors.forename: A N
authors.initials: AN
authors.lastname: Anila
authors.forename: N
authors.initials: N
authors.lastname: Balakrishna
authors.forename: Suvarna
authors.initials: S
authors.lastname: Alladi
authors.forename: A
authors.initials: A
authors.lastname: Jyothy
mesh_terms: D000328:Adult; D016009:Chi-Square Distribution; D004252:DNA Mutational Analysis / Q000379:methods; D005260:Female; D005787:Gene Frequency; D020022:Genetic Predisposition to Disease; D005838:Genotype; D006801:Humans; D007194:India / Q000453:epidemiology; D007438:Introns / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D018598:Minisatellite Repeats / Q000235:genetics*; D052250:Nitric Oxide Synthase Type III / Q000235:genetics*; D011110:Polymorphism, Genetic / Q000235:genetics*; D012189:Retrospective Studies; D020521:Stroke / Q000453:epidemiology / Q000235:genetics*
chemical_list: D052250:Nitric Oxide Synthase Type III