Epigenetics doesn’t change the genetic code, it changes how that’s read. Perfectly normal genes can result in cancer or death. Vice-versa, in the right environment, mutant genes won’t be expressed. Genes are equivalent to blueprints; epigenetics is the contractor. They change the assembly, the structure.
Science ignores the spiritual realm because it is not amenable to scientific analysis. As importantly, the predictive success of Newtonian theory, emphasizing the primacy of a physical Universe, made the existence of spirit and God an extraneous hypothesis that offered no explanatory principles needed by science.