The genome of a species is not static. While there is a strong influence of the genotype on the phenotype, not all of the gene functions and expressions are due to changes in the DNA sequence alone. Many processes have been identified in which there is interaction with proteins or where post-synthetically changes to the DNA sequence are observed. The role of RNA and especially non-coding RNA (ncRNA) is a major controlling element in many epigenetic processes.
There are many methods to quantify DNA methylation. Among them are PCR, real-time PCR and high resolution melt curve assays. GC biotech offers the Bioline Epigenetics products to enable the research in these areas.