Genes are the sole determinants of traits

Usually, factors other than genes also influence traits. While some qualities, like blood type, are only impacted by genetics, the majority of attributes are influenced by both our environment and genes. We do not inherit a disease; rather, we inherit risk factors for developing a disease. For instance, new research indicates that 50 to 60 percent of the risk of alcoholism is genetic (National Institute on Alcohol Abuse and Alcoholism).

The remaining 40 to 50 percent of the risk is therefore environmental. Due to a person's family's history with alcoholism, they may be genetically predisposed to the disease. However, adopting a healthy lifestyle, such as limiting alcohol consumption, can assist someone avoid developing an alcohol dependence. Those who are prone to obesity may experience the same effects from the environment. Multiple genes interact to cause obesity, which has a hereditary component.

Studies, however, present wildly disparate findings about the level of genetic input. Even though obesity runs in the family, a person can avoid it by choosing nutritious foods and engaging in regular exercise. What characteristics we will and won't have is not predetermined by our genes. In the end, a person can help lower the risk of certain diseases by leading a healthy lifestyle and learning the diseases they are genetically prone to.