Ercüment ÖZKEÇECİ, TEVFİK GÜLYAŞAR, Serap ŞENER

The association of hypertension and C825t polymorphism of the gene encoding the G-protein beta-3 subunit (GNB3) in a group of Turkish hypertensive patients

Amaç: G proteini beta-3 (β3) altbirimini (GNB3) kodlayan genin C825T polimorfizmi G proteinleri yoluyla sinyal iletiminde artışla ve sonuçta artmış Na+/H+ değiştiricisinin aktivitesi ile ilişkilidir. Bu iyon taşıma sistemi proksimal tübülden sodyum geri emilimine aracılık eder. Değişik nüfuslardan hipertansif hastaların hücrelerinde Na+/H+ değiştiricisinin aktivitesinde artış bulunmuştur. Bu çalışmada hipertansiyonlu Türk hasta grubunda bu polimorfizm araştırıldı ve normotansif bireylerle karşılaştırıldı. Hastalar ve Yöntemler: Doksan dokuz hipertansif hasta (57 erkek, 42 kadın) ve 45 normotansif kontrolde (33 erkek, 12 kadın) GNB3 C825T polimorfizmi için genotipleme yapıldı. Bulgular: Hasta ve kontrol gruplarında alel dağılımı sırasıyla CC:35, CT:51, TT:13 ve CC:26, CT:15, TT:4 şeklindeydi. T aleli taşıyıcıları (CT ve TT) hipertansiyonlu grupta anlamlı şekilde daha yüksekti. Hipertansiyon ve C825T aleli arasında istatistiksel bakımdan anlamlı ilişki (Ki-kare testi, p=0.041) bulundu. Sonuç: Bu bulgular Türk hastalarda hipertansiyon ve GNB3 polimorfizminin ilişkili olduğunu ve artmış G proteini aktivitesinin C825T ile hipertansiyon arasındaki patofizyolojik bağlantı olabileceğini düşündürmektedir.

Anahtar Kelimeler:

Polimorfizm, genetik, Genotiplendirme teknikleri, Hipertansiyon, GTP-bağlayıcı proteinler

Hipertansiyonlu Türk hasta grubunda hipertansiyon ile G proteini beta-3 altbirimini kodlayan gende C825T polimorfizmi arasındaki ilişki

Objectives: The C825T polymorphism of the gene encoding the G-protein beta-3 subunit (GNB3) is associated with enhanced signal transduction via G proteins which in turn results in an increased Na+/H+ exchanger activity. This ion transport system mediates sodium reabsorption in the proximal tubule. Increased activity of Na+/H+ exchanger was found in the cells of patients with arterial hypertension in different populations. We investigated this polymorphism in a Turkish group of patients with hypertension and compared them with normotensive subjects. Patients and Methods: 99 hypertensive patients (57 males, 42 females) and 45 normotensive controls (33 males, 12 females) were genotyped for the GNB3 C825T polymorphism. Results: Allele distribution of patient and control groups were CC: 35, CT: 51, TT: 13 and CC: 26, CT: 15, TT: 4, respectively. T-allele carriers (CT and TT) were significantly higher in hypertensive group. There was also a statistically significant (Chi-square test, p=0.041) relationship between 825T allele and hypertension. Conclusion: These results suggest that hypertension is related with GNB3 polymorphism in Turkish patients and increased G protein activity may be the pathophysiologic link between C825T and hypertension.

Keywords:

Polymorphism, Genetic, Genotyping Techniques, Hypertension, GTP-Binding Proteins,

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