A gene passed to you from a parent is in every cell of the body that develops. If it has an effect on your traits, there is no way to expunge it from every cell in order to eliminate that effect.
One complication to this line of thinking is that the immutable gene, even when that gene has severe implications for the body, is insufficient to dictate the social implications for the person. Someone I came to know with muscular dystrophy was, in the 1960s, what we now call mainstreamed at school at his mother’s insistence. High school friends who went on to university with him initiated a pattern of what we now call independent living that continued as his physical condition required sleeping in an iron lung. Meanwhile, he worked as a counsellor first for students then at centers for the disabled and became a parent, living decades beyond the expected 20 or so years for a male at that time with muscular dystrophy (Duchene). The gene mutation on his X chromosome never stopped having its effect and the social support he required was not simple, but a fulfilling life was possible.
(Introduction to this series of posts)