ARTERİYO-VENÖZ FİSTÜL TROMBOZU GELİŞEN VE GELİŞMEYEN KRONİK BÖBREK YETMEZLİĞİ OLAN HASTALARDA METİLENTETRAHİDROFOLAT REDÜKTAZ POLİMORFİZMLERİNİN ARAŞTIRILMASI

Öz

Metilentetrahidrofolat redüktaz (MTHFR), folat döngüsünde önemli bir rol oynar ve homosistein metabolizmasına katkıda bulunur. MTHFR genindeki bazı mutasyonlar, MTHFR geninin enzim aktivitesinde azalmaya neden olabilir. MTHFR geninde yaygın olarak C677T ve A1298C polimorfizmleri görülür. Bu çalışmada kronik böbrek yetmezlikli (KBY) hastalarda MTHFR C677T ve MTHFR A1298C polimorfizmlerinin etkisi araştırılmıştır. Bu amaçla nedeni bilinmeyen arteriyovenöz fistül trombozu gelişen KBY’li 31 kişi hasta grubu ve fistül tıkanması görülmeyen KBY’li 51 kişi kontrol grubu olarak çalışıldı. Periferal kan örnekleri alınarak DNA izole edildi. MTHFR C677T ve MTHFR A1298C polimorfizmi PCR-RFLP yöntemi ile belirlendi. MTHFR C677T polimorfizminin hasta ve kontrol grubunda normal genotipli birey sayısı sırasıyla 27 (%87.09) ve 44 (%86.27), heterozigot genotipli birey sayısı 4 (%12.90) ve 6 (%11.76) olarak tespit edildi. Hasta grubunda homozigot mutant genotip bulunmazken kontrol grubunda bir kişide (%2) tespit edildi. MTHFR A1298C polimorfizminin hasta ve kontrol grubunda normal genotipli birey sayısı sırasıyla 12 (%38.70) ve 14 (%27.50) olarak; heterozigot genotipli birey sayısı sırasıyla 12 (%38.70) ve 25 (%49), homozigot mutant genotipli birey sayısı 7 (%22.60) ve 12 (%23.50) olarak tespit edildi. Araştırma sonucunda kronik böbrek yetmezlikli hasta ve kontrol grubu arasında MTHFR C677T ve A1298C genotipleri ve allel sıklıkları açından önemli bir fark bulunamadı. Elde edilen bulgular KBY’li hastalarda MTHFR C677T ve MTHFR A1298C polimorfizmlerinin tromboz riskini etkilemediğini işaret etmektedir

Anahtar Kelimeler

• Kronik böbrek yetmezliği, MTHFR, A1298C, C677T

Researching Methylenetetrahydrofolate Reductase Polymorphisms in Chronic Renal Failure Patients with Developing and Non-Devoloping Arterio-Venous Thrombosis

Öz

Methylenetetrahydrofolate reductase (MTHFR) plays an important role in the folate cycle and contribures to the metabolism of the aminoacid homocysteine. Some of the mutations in the MTHFR gene cause a decrease in MTHFR activity. Particularly C677T and A1298C mutations in MTHFR gene are two common polymorphisms. The aim of this study is to find out the relationship between MTHFR C677T/A1298C mutations and chronic renal failure patients. Thirty-one chronic renal failure patients with developing arteriovenous thrombosis and 51 chronic renal failure patients with nondeveloping arterio-venous thrombosis were chosen. DNA was extracted from peripheral blood samples of the patients and controls. MTHFR C677T and MTHFR A1298C polymorphisms was identified by PCR (polymerase chain reaction)-RFLP (restriction fragment length polymorphism) methods. MTHFR C677T polymorphism in patients and control group normal genotype was found in 27 (87.09%) and 44 (86.27%), heterozygote genotype 4 (12.90%) and 6 (11.76%). No homozygote subjects were found in patients group but one subject were detected in the control group (2%). MTHFR A1298C polymorphism in patients and control group normal genotype was found in 12 (38.70%) and 14 (27.50%), heterozygote genotype 12 (38.70%) and 25 (49%), homozygote genotype 7 (22.60%) and 12 (23.50%). MTHFR C677T and MTHFR A1298C genotype and allele frequency were not significantly different in patients and control groups with chronic renal failure. As a result, MTHFR C677T and MTHFR A1298C polymorphisms are not a risk factor for thrombosis in chronic renal failure patients

Anahtar Kelimeler

• Chronic renal failure, MTHFR, A1298C, C677T

Kaynakça

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