Ceylan BAL, Metin YILDIRIMKAYA, Gönül ERDEN, Nihal UĞUZ, Oya GÜNGÖR

MTHFR geninde c677t ve/veya a1298c polimorfizmi tespit edilen bireylerde bu polimorfizm sıklıklarının incelenmesi

Amaç: MTHFR enzimi 5,10 metilentetrahidrofolatı 5 metiltetrahidrofolata katalize ederek, homosisteinden metionin remetilasyonu için gerekli olan aktif folat formunu oluşturur. Bu enzimi kodlayan gendeki mutasyonlar ile birçok hastalık arasındaki ilişki araştırılmaktadır. Çalışmalar, en iyi bilinen MTHFR C677T ve A1298C polimorfizmleri üzerinde yoğunlaşmaktadır. Bu çalışma, MTHFR geninde C677T ve A1298C polimorfizm tespit edilen bireylerde bu polimorfizmlerin sıklığını saptamak amacıyla planlanmıştır.Gereç ve yöntem: Çalışmaya, Ankara Numune Eğitim ve Araştırma Hastanesi III Biyokimya Laboratuvarı’nda C677T ve A1298C yönünden MTHFR polimorfizmi saptanan toplam 164 birey dahil edildi. Hastaların 44’ü erkek, 120’si kadındı. Tüm hastaların yaş ortalaması 48,4±16,8 yıl (yaş aralığı 18-76) idi. MTHFR polimorfizmi, ROCHE Light Cycler 1.5 Real Time PCR ile çalışıldı. Bulgular: Çalışmaya alınan 164 polimorfizmli bireyin 109’unda (% 66,5) MTHFR C677T polimorfizmi saptandı. Bu bireylerin 89’u (% 54,3) heterozigot iken 20’si (%12,2) homozigot mutant tipti. Yine 95 (%57,9) bireyde A1298C polimorfizmi tespit edildi. Bunların 76’sı (%46,3) heterozigot, 19’u (% 11,6) homozigot mutant genotipe sahipti. Her iki polimorfizmin heterozigot birlikte bulunduğu hasta sayısı 40 (% 24,4) idi. Çalışma grubunda, MTHFR C677T ve MTHFR A1298C polimorfizm sıklıkları açısından fark tespit edilmedi (p>0,05). Sonuç: Çalışmamızda, polimorfizm tespit edilen bireylerde, MTHFR A1298C polimorfizminin de C677T kadar sık bulunabileceği görüldü.

Determination of the frequency of MTHFR C677T and MTHFR A1298C polymorphisms in persons with polymorphic MTHFR gene

Objectives: Relationship between several diseases and the mutations on the gene that is encoding MTHFR enzyme has been investigated. Studies are focused on the best known mutations; MTHFR C677T and A1298C. This study is planned for determining the frequency of C677T and A1298C polymorphism of MTHFR gene for individuals who have this kind of polymorphisms. Materials and methods: 164 individuals who were determined MTHFR polymorphism in Ankara Numune Educa- tion and Research Hospital Biochemistry Laboratory were included in the study. 44 of them were men and 120 of them were women. The mean of age of the patients were 48,4±16,8 year (18-76). MTHFR polymorphism was assayed by ROCHE Light Cycler 1.5 Real Time PCR. Results: In 109 of 164 patients (66.5%) MTHFR C677T polymorphisms were determined. While 89 of these patients (54.3%) were heterozygote, 20 of them were (12.2%) homozygote mutant type. In 95 patients (57.9%) A1298C mutation was determined, 76 (46.3%) were heterozygote and 19 of them (11.6%) had homozygote mutant genotype. Patients number with both mutations together was 40 (24.4%). In the study group, no difference was found in frequency of MTHFR C677T and MTHFR A1298C polymorphisms (p>0.05). Conclusions: In our study, it is seen that in individuals determined polymorphism, even MTHFR A1298C polymorphism can be found as frequent as C677T polymorphism.

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