Why are studies of identical twins important in understand interactions between environment and genotype?

Since hereditarily they ought to be indistinguishable so any contrasts between them will be caused by their condition. Since indistinguishable twins create from a solitary prepared egg, they have a similar genome. So any contrasts between twins are because of their surroundings, not hereditary qualities. Late examinations have demonstrated that numerous naturally actuated contrasts are reflected in the epigenome.