5-hydroxymethylcytosine (5-Hydroxymethyl-C) is also known as “the sixth base”, given that it has been detected in all animal tissues, with particularly high level in promoter and intragenic regions. 5-hydroxymethylcytosine derives from 5-mC, which plays an important role as an epigenetic marker in gene expression and regulation. However, which role 5-hydroxymethylcytosine plays is still not clear. Incorporation of this base in synthetic oligonucleotides will help researchers elucidating the role of this base.

ModifiedBasis 5 hydroxymethyl C

Metabion offers 5-Hydroxymethyl-C in its DNA portfolio. Click here

MW 319.2 g/mol
Extinction coefficient (260 nm) 7 mM-1cm-1


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H. Sasaki, and Y. Matsui.  Epigenetic events in mammalian germ-cell development: reprogramming and beyond. Nat. Rev. Genet. (2008), 9: 129-140.

M. Tahiliani, K.P. Koh, Y. Shen, W.A. Pastor, H. Bandukwala, Y. Brudno, S. Agarwal, L.M. Iyer, D. Liu, L. Aravind, and A. Rao. Conversion of 5-Methylcytosine to 5-Hydroxymethylcytosine in Mammalian DNA by MLL Partner TET1 Science (2000), 324: 930-935.

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