Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein. Genes are the part of a body cell that contain the biological information that parents pass to their children. Genes control the growth and development of cells. Genes are made of DNA (deoxyribonucleic acid), a substance inside the center (nucleus) of cells that contains instructions for the development of the cell. You inherit half of your genetic information from your mother and the other half from your father. Genes, alone or in combination, determine what features (genetic traits) a person inherits from his or her parents, such as blood type, hair color, eye color, and other characteristics, including risks of developing certain diseases. Certain changes in genes or chromosomes may cause problems in various body processes or functions. Many genes together make up larger structures within the cell called chromosomes. Each cell normally contains 23 pairs of chromosomes. A human has 46 chromosomes (23 pairs). One chromosome from each pair comes from the mother, and one chromosome from each pair comes from the father. One of the 23 pairs determines your sex. These sex chromosomes are called X and Y. Some genetic conditions are caused when all or part of a chromosome is missing or when an extra chromosome or chromosome fragment is present. Genetic testing includes any type of test that checks a person's DNA. Tests often use a sample of cells or tissue to look for changes in genes, chromosomes, or proteins. These changes can be a sign of a disease or a sign of an increased risk for getting a disease. Testing may be done to: The results of genetic testing can affect your life. It may be a good idea to get genetic counseling before deciding to have testing. Genetic counselors can explain the pros and cons of testing, but you make the decision about whether to have the test. A genetic counselor can help you make well-informed decisions. Genetic counseling can help you and your family: Genetic counselors have specialized training in medical genetics and counseling. They are sensitive to the physical and emotional aspects of these decisions. Your privacy and confidentiality are carefully protected. Current as of: November 15, 2023 Author: Healthwise Staff Current as of: November 15, 2023 Author: Healthwise Staff Clinical Review Board This information does not replace the advice of a doctor. Healthwise, Incorporated disclaims any warranty or liability for your use of this information. Your use of this information means that you agree to the Terms of Use and Privacy Policy. Learn how we develop our content. To learn more about Healthwise, visit Healthwise.org. © 1995-2024 Healthwise, Incorporated. Healthwise, Healthwise for every health decision, and the Healthwise logo are trademarks of Healthwise, Incorporated.Topic Contents
Genetics
Overview
What are genes?
What are chromosomes?
What is genetic testing?
How can genetic counseling help?
Related Information
Credits
Clinical Review Board
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.
Our Health Library information does not replace the advice of a doctor. Please be advised that this information is made available to assist our patients to learn more about their health. Our providers may not see and/or treat all topics found herein. Current as of: November 15, 2023 Author: Healthwise Staff Clinical Review BoardGenetics
All Healthwise education is reviewed by a team that includes physicians, nurses, advanced practitioners, registered dieticians, and other healthcare professionals.