DNA Metilasyonu

Metilasyon, biyolojik sistemlerde, genomun normal olarak düzenlenmesini ve gelişmesini sağlayan kimyasal bir reaksiyondur. Epigenetik mekanizmanın en iyi bilinenidir. Gen aktivasyonu, baskılanması ve kromatin şekillenmesi gibi epigenetik olaylarda yani gen ekspresyonunun düzenlenmesini sağlayan metilasyon, iki sistem içermektedir. Bu sistemlerden biri DNA metilasyonu diğeri ise protein (histon) metilasyonudur. Bunlar bazı yapısal anomaliler ve hastalıklar ile ilişkilidir. Bu derleme, metilasyonun genomdaki fonksiyonunu, nasıl düzenlendiğini ve hangi hastalıklara neden olduğunun altı çizilmiştir. Ayrıca metilasyonun hastalıklardaki rolü ve epigenetik mekanizmalardaki fonksiyonu anlatılmıştır.

DNA Methylation

Methylation is a chemical reaction in biological systems for normal genome regulation and development. It is a well known type of epigenetic mechanism. Methylation which regulates gene expression via epigenetic events like gene activation, repression, and chromatin remodelling, consists of two methylation systems. One of these systems is DNA methylation whereas the other is protein (histone) methylation. These systems are associated with some fundamental abnormalities and diseases. This review highlights the role of methylation in normal genome function, how it can be arranged and which diseases it cause. Furthermore, the role of methylation in some diseases and its functions in epigenetic mechanism has been reviewed.

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