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DNA methylation at cytosine bases of CpG dinucleotide is an epigenetic phenomenon widely used to regulate gene expression in humans [1]. CpG islands are often present in 5′-upstream region of genes and methylation of these is associated with condensed chromatin and re-pressed gene transcription [2,3]. As a heritable change, DNA methylation plays an important role in embryonic development, genomic imprinting and X-chromosome inactivation [4,5]. Alterations in DNA methylation is known to be affected by number of environmental fac-tors to influence human diseases and is also associated with genetic events that leads to several types of cancer [6]. Growing evidences suggest that enzymatic machin-eries such as DNA methyltransferases (DNMTs) are re-sponsible for creating and maintaining patterns of DNA methylation in response to environmental factors and during developmental programs [7,8]. The broad classification of phenotypic variations base