Information for Patients
Your family history includes health information about you and your close relatives. Families have many factors in common, including their genes, environment, and lifestyle. Looking at these factors can help you figure out whether you have a higher risk for certain health problems, such as heart disease, stroke, and cancer.
Having a family member with a disease raises your risk, but it does not mean that you will definitely get it. Knowing that you are at risk gives you a chance to reduce that risk by following a healthier lifestyle and getting tested as needed.
You can get started by talking to your relatives about their health. Draw a family tree and add the health information. Having copies of medical records and death certificates is also helpful.
Centers for Disease Control and Prevention
Genes are the building blocks of heredity. They are passed from parent to child. They hold DNA, the instructions for making proteins. Proteins do most of the work in cells. They move molecules from one place to another, build structures, break down toxins, and do many other maintenance jobs.
Sometimes there is a mutation, a change in a gene or genes. The mutation changes the gene's instructions for making a protein, so the protein does not work properly or is missing entirely. This can cause a medical condition called a genetic disorder.
You can inherit a gene mutation from one or both parents. A mutation can also happen during your lifetime.
There are three types of genetic disorders:
- Single-gene disorders, where a mutation affects one gene. Sickle cell anemia is an example.
- Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed. Chromosomes are the structures that hold our genes. Down syndrome is a chromosomal disorder.
- Complex disorders, where there are mutations in two or more genes. Often your lifestyle and environment also play a role. Colon cancer is an example.
Genetic tests on blood and other tissue can identify genetic disorders.
NIH: National Library of Medicine