The human genome is stable. In case of any damage to the body - internal or external, it tries to return to the original, reference state written in the DNA chains. Sometimes this system stops working as it should - and most often this leads to very sad consequences. People still know too little to interfere with the work of this most complex megafactory of self-reproduction and add something new to it. But this is only true for the current reality of planet Earth. But in the conditions of the boiling cauldron of another world, it is impossible to survive without changing. But how far you are ready to deviate from the standard, and why you are doing it, is up to you.