Absolutely! We are not static beings–we are constantly changing. Our genes express themselves differently at different points in our lives, and we can deliberately influence our own development by the choices we make.
There is no single “true self” that exists apart from our experiences and choices. We are constantly evolving, and we have the power to create ourselves anew. Every moment offers us the opportunity to choose who we want to be and to create a new reality for ourselves. So yes, it is absolutely possible to completely change who we are!