Unit 1 Taking Charge of Your Health and Wellness Copyright Goodheart-Willcox Co., Inc. 16 Genetic Factors Genetic factors relate to your genes. Your genes are present in every cell in your body. They contain the blueprint for the structure and function of your cells. Genes direct how you grow and develop, influence your personality, and affect your health. Humans have 20,000 to 25,000 genes, which are composed of a chemical often referred to as DNA. Located in a cell’s nucleus, genes are bundled in packages called chromosomes (Figure 1.7). Humans inherit half of their chromosomes from each biological parent. The unique combination of genes from your parents determines many of your characteristics. For example, your nose might be shaped like one parent’s nose. You and one parent may both have red, wavy hair. Perhaps you have blue eyes like your parents. The genes you receive from your parents can affect your health and wellness by putting you at risk for developing certain diseases, such as heart disease. In this way, your family influences your health. To determine a person’s genetic risk factors for developing a disease, doctors study a person’s family history, the record of disease within a family. Risk factors are aspects of people’s lives that increase the chance of a disease, injury, or decline in health. Although you cannot change the genes you receive, there are actions you can take to reduce the risk factors for developing genetically linked diseases and disorders. The first step is to learn about your family’s history of diseases. Do you have a family history of heart disease, cancer, or diabetes? Ask your biological relatives for information. Then, learn about the risk factors linked to the diseases that run in your family. For example, leading an inactive lifestyle and smoking are both risk factors for developing heart disease. Cell Nucleus Chromosome DNA Gene Cell Structure Designua/Shutterstock.com Figure 1.7 Each cell in your body contains a total of 46 chromosomes (23 pairs), which hold about 20,000 to 25,000 genes. One set of 23 chromosomes is inherited from your biological mother and the other set of 23 is from your biological father. Where are genes located?