Epigenetics is the study of how your behaviors and environment can cause changes that affect the way your genes work. Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence.
You have a predisposition for developing fingerprints.Identical twins don't have the same fingerprints.https://www.datebytype.com/blogs/view/120/Why-are-epigenetics-important-to-rh-negatives
These fingerprints start forming in the 10th week after conception when some cells in the middle layer of the skin, called the basal layer, start growing faster than the cells in the inner layer of dermis or outer layer of epidermis. The extra cells cause the skin to buckle and fold into ridges.
Source: Charlotte Lozier Institute
Part 1:
https://www.datebytype.com/blogs/view/120/Why-are-epigenetics-important-to-rh-negatives