For the other polymorphic site (rs7536927, T > A), no association between genotypes or combined alleles and hypertension was found in the whole study population (P = 0.29 for genotypes and P = 0.24 for A-allele carriers). However, when subjects were stratified according to weight, carriers of the A-allele whose BMI was less than 30 had more often hypertension compared with those homozygous for the wild type (TT) (OR = 1.56, P = 0.04, 95% CI 1.01–2.39) (Table 4.) As with the rs7536827, no association with coronary artery disease was found (Table 2).
Although the mechanism is not yet known, our results suggest that the minor allele G of the HJV variant (rs16827043) is associated with higher risk for hypertension at the age of 50 years, compared with the AA-genotype carriers. In addition, we found that among normal or slightly overweight individuals, also T-allele of the HJV rs7536827 increases the risk for hypertension. It is therefore possible that dysregulation in iron metabolism is a significant factor behind hypertension. Abnormalities in iron homeostasis and relationship between iron metabolism and hypertension warrant further studies.
The authors thank all of the participants of the TAMRISK study and Mirka Pietiläinen and Ulla Saarijoki for their skilful technical assistance.
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