The unique code of DNA you were born with (your personal genome) affects your health, appearance, and many other traits that make you unique. However, that is only part of the story. Your genome is dynamic over the course of your lifetime. Consider the following:
- There are trillions of bacteria, viruses, and yeast and other fungi (collectively called microbes) that live in and on our bodies. These microbes can affect our health, our digestion, and maybe even our moods. Our personal make-up of microbes can be affected by the foods we eat, the people we kiss, the surfaces we touch, our use of antibiotics and sanitizers, and more.
- Mutations are simply changes in one’s DNA sequence and are not necessarily bad or good. Mutations can arise when a cell makes a mistake copying its DNA or upon exposure to environmental insults, such as UV rays or certain chemicals. As a result of a mutation in one cell, the DNA in that cell will now be slightly different from the DNA in the neighboring cell. When the cell divides, it will pass on the mutation to its descendants the occurrence of mutations that change the DNA in a single cell and its descendants. (Note: only certain cells in our bodies can give rise to egg and sperm. Therefore, a mutation that arises in a cell in your big toe will not be passed down to your children.
- Some people carry genetically distinct cells that originate from another individual. These may be people who have received bone marrow transplants or women who have carried a pregnancy.
In addition, personal genetics reflects the influences of our environment, lifestyle, and social experiences on how our genes work (epigenetics).
As a result, our genes are only part of a much more complex story of who we are and what our future holds. The growing field of personal genetics is at the intersection of science and society; it is both an exploration into the complex interactions through which our genes and our environment influence our physical, mental and behavioral states as well as an on-going conversation on the meaning for individuals and society.