A genetic test is a simple blood test that your health care provider can order to better understand how your body works. Genetic testing typically involves looking at specific genes in the body, including those that may impact how medications work.1 Genes are the instruction manuals for the body, and are written in the “language” of DNA. Because genes do not change, you only need to test a specific gene once. Genes are passed down from generation to generation, but mutations can sometimes happen during the process. Mutations are changes in the DNA language of a gene, like how sentences change during a game of telephone. Small mutations can lead to big effects. Just look at what a big impact a small difference can make!