People can be at a higher risk of developing cancer from their genetic makeup, or DNA. More specifically, certain mutated genes can be passed onto children from generation to generation, something you can’t prevent or control the effect of. The American Cancer Society explains that cancer is believed to be formed from more than one gene mutation, so you aren’t likely to develop cancer just from one mutated gene inherited through DNA. However, people who inherit these faulty genes are then at a disadvantage because they’re automatically starting off with one mutated gene.
Breast cancer is a prime example of this—there are two genes that can be inherited, which can greatly increase the risk of breast cancer within families or lineages. There’s testing that can be done to find out if you have one of these risky genes, and it’s believed that around 5- to 10-percent of breast cancer cases are caused by them. Although many women and some men are diagnosed with breast cancer each year, it’s something that is often caught early enough to treat and overcome.