The epigenetic supersimilarity of monozygotic twins
Monozygotic twins are identical individuals born from the fertilization of a single egg cell from a sperm that have the same genetic makeup. The common elements between two identical twins do not only concern genetics but also involve epigenetics, that is the set of molecular mechanisms that regulate the expression of genes without modifying the DNA. A type of epigenetic modification studied in twins is methylation which consists in the addition of a methyl group (-CH3) to a nitrogenous base. Through the study of metastable epialleles (ME), epigenetic variants set up in the early embryo and maintained during subsequent cell differentiation, it was possible to observe that [...]