Methods: DNA methylation.

Abstract

Since it was discovered, there was an increased interest in the analysis and the quantification of DNA methylation. In mammals this modification of DNA occurs mainly at cytosines in a CpG context (i.e. cytosine followed by guanine in 5’ to 3’ direction). DNA methylation is involved in many basic biological processes as control of gene expression in tissue specific manner and at imprinted genes (Hikichi et al, 2003; Futscher et al, 2002). Indeed alteration of the normal patterns of methylation has been observed in many imprinting diseases and in many tumor tissues (Widschwedter and Jones, 2002; Walter and Paulsen, 2003).