Association of the Apolipoprotein B Gene Polymorphisms With Essential Hypertension in Northern Chinese Han Population

Objective To study the association of the apolipoprotein B gene polymorphisms with essential hypertension in Northern Chinese Han population. Methods XbaI and EcoRl polymorphisms of the apolipoprotein B （APOB） gene were genotyped by polymerase chain reaction （PCR） and restriction fragment-length polymorphism （RFLP） method in 503 unrelated hypertensive patients and 490 healthy controls recruited from international collaborative study of cardiovascular disease in Asia （InterAsia）. Results The difference in the genotypic distributions could be neglected across the groups. The prevalence of X＋ allele in healthy controls （4.8%） was less frequent in Chinese, and there was no significant difference in the frequency of the X＋ allele between cases （5.7%） and controls （P=0.38）. The observed E- allele frequencies were closely similar among groups （5.9% in cases vs 5.0% in controls, P=0.39）. Logitstic regression analyses revealed that the lack of association still persisted after adjustment of other environmental factors. Haplotype analysis showed that X-E＋ was most frequent and no haplotype could significantly contribute to essential hypertension. Conclusion The APOB gene XbaI and EcoRI polymorphisms are not associated with essential hypertension in the Northern Chinese Han population. Future studies on single nucleotide polymorphisms in larger samples are needed to further investigate the possible contribution of the APOB gene to essential hypertension.

Genetic variants in the ADD1 and GNB3 genes and bloodpressure response to potassium supplementation

Dietary potassium-supplementation has been associated with a decreased risk of hypertension and other cardiovascular outcomes.However,blood pressure(BP)responses to potassium supplementation vary among individuals.This study was designed to examine the association between 12 single nucleotide polymorphisms(SNPs)in the adducin 1 alpha(ADD1)and guanine nucleotide binding protein(G protein)beta polypeptide 3(GNB3)genes and systolic BP(SBP),diastolic BP(DBP),and mean arterial pressure(MAP)responses to potassium-supplementation.We conducted a 7-day high-sodium intervention(307.8 mmol sodium/day)followed by a 7-day high-sodium with potassium-supplementation(60 mmol potassium/day)among 1906 Han Chinese participants from rural north China.BP measurements were obtained at the end of each intervention period using a random-zero sphygmomanometer.We identified significant associations between ADD1 variant rs17833172 and SBP,DBP,and MAP responses to potassium-supplementation(all P<0.0001)that remained significant after adjustment for multiple comparisons.In participants that were heterozygous or homozygous for the G allele of this marker,SBP,DBP,and MAP response to potassium-supplementation were–3.52(–3.82,–3.21),–1.41(–1.66,–1.15)and–2.12(–2.37,–1.87),respectively,as compared to the corresponding responses of 1.99(0.25,3.73),–0.65(–0.10,–0.21),and–0.23(–0.37,0.83),respectively,for those who were homozygous for A allele.In addition,participants with at least one copy of the G allele of rs12503220 of the ADD1 gene had significantly increased DBP and MAP response to potassium-supplementation(P=0.0041 and 0.01,respectively),which was also significant after correction for multiple testing.DBP and MAP responses to potassiumsupplementation were–1.36(–1.63,–1.10)and–2.07(–2.32,–1.82)for those with at least G allele compared to corresponding responses of 0.86(–0.68,2.40)and–0.45(–1.74,0.84)for those who were homozygous for A allele.In summary,our study identified novel associations between genetic variants of the ADD1 gene and BP response to potassium-supplementation,which could have important clinical and public health implications.Future studies aimed at replicating these novel findings are warranted.