Your genome is the operating manual containing all the instructions that helped you develop from a single cell into the person you are today. It guides your growth, helps your organs to do their jobs, and repairs itself when it becomes damaged. And it’s unique to you. The more you know about your genome and how it works, the more you'll understand your own health and make informed health decisions.
The DNA Double Helix
Genomes are made of DNA, an extremely large molecule that looks like a long, twisted ladder. This is the iconic DNA double helix that you may have seen in textbooks or advertising.
DNA is read like a code. This code is made up of four types of chemical building blocks, adenine, thymine, cytosine, and guanine, abbreviated with the letters A, T, C, and G. The order of the letters in this code allows DNA to function in different ways. The code changes slightly from person to person to help make you who you are.
Explore![DNA bases](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/media/images/2019-03/DNA-detail4.jpg)
![Your Genome](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/media/images/2019-03/Your_genome2_0.jpg)
The Role of Your Parents
The instructions necessary for you to grow throughout your lifetime are passed down from your mother and father. Half of your genome comes from your biological mother and half from your biological father, making you related to each, but identical to neither. Your biological parents' genes influence traits like height, eye color, and disease risk that make you a unique person.
![Your Life Your Environment](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/media/images/2019-03/Yourlife_environment2.jpg)
Does my genome determine everything about me?
Not entirely. Genomes are complicated, and while a small number of your traits are mainly controlled by one gene, most traits are influenced by multiple genes. On top of that, lifestyle and environmental factors play a critical role in your development and health. The day-to-day and long-term choices you make, such as what you eat, if you smoke, how active you are, and if you get enough sleep, all affect your health.
DNA is not your destiny. The way you live influences how your genome works.
![Genetic Disorders | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5_Genetic_Disorders.jpg)
A list of genetic, orphan and rare diseases under investigation by researchers at or associated with the National Human Genome Research Institute.
![About Autism | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.4_Autism.jpg)
Autism is characterized by impaired social interactions, problems with verbal and nonverbal communication and repetitive behaviors.
![About Breast Cancer | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.6_Breast_Cancer.jpg)
Breast cancer is the second most common cancer in women after skin cancer.
![About Cystic Fibrosis | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.11_Cystic_Fibrosis.jpg)
Cystic fibrosis is a genetic disease that causes the body to produce thick, sticky mucus that clogs the lungs, leads to infection, and blocks the pancreas.
![About Down Syndrome | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/_4.2.5.13_Down_Syndrome.jpg)
Down syndrome is a chromosomal condition related to chromosome 21.
![About Parkinson's Disease | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.32_Parkinson_s_Disease.jpg)
Parkinson's disease is a neurological condition that typically causes tremor and/or stiffness in movement
![Sickle Cell Disease | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.40_Sickle_Cell_Disease.jpg)
Sickle cell disease is a group of inherited red blood cells disorders.
![About Wilson Disease | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.48_Wilson_Disease.jpg)
Wilson disease is a rare genetic condition that causes a person's body to store too much of the mineral copper, leading to organ damage that may cause death.
![Attention Deficit Hyperactivity Disorder (ADHD) | NHGRI](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/4.2.5.51_Attention_Deficit_Hyperactivity_Disorder__ADHD_.jpg)
Attention Deficit Hyperactivity Disorder (ADHD) is a neurological disorder that affects a person's ability to control their behavior and pay attention to tasks.
Predictive testing is for those who have a family member with a genetic disorder. The results help to determine a person’s risk of developing the specific disorder being tested for. These tests are done before any symptoms present themselves.
Diagnostic testing is used to confirm or rule out a suspected genetic disorder. The results of a diagnostic test may help you make choices about how to treat or manage your health.
Pharmacogenomic testing tells you about how you will react to certain medications. It can help inform your healthcare provider about how to best treat your condition and avoid side effects.
Reproductive testing is related to starting or growing your family. It includes tests for the biological father and mother to see what genetic variants they carry. The tests can help parents and healthcare providers make decisions before, during, and after pregnancy.
Direct-to-consumer testing can be completed at home without a healthcare provider by collecting a DNA sample (e.g., spitting saliva into a tube) and sending it to a company. The company can analyze your DNA and give information about your ancestry, kinship, lifestyle factors and potential disease risk.
Forensic testing is carried out for legal purposes and can be used to identify biological family members, suspects, and victims of crimes and disasters.
What are the benefits for my health?
One way genomics research can benefit you is through the emerging field of precision medicine. Specifically, characteristics of your genome can help predict how you will react to certain medications, allowing your healthcare provider to choose the appropriate prevention or treatment options for you.
![Pill box](https://webarchive.library.unt.edu/web/20201218012153im_/https://www.genome.gov/sites/default/files/media/images/2019-03/HealthBenefits2.jpg)
Impact on Society
Whether you realize it or not, many parts of our daily lives are influenced by genomic information and technologies. Genomics now provides a powerful lens for use in various areas, including medical decisions, food safety, ancestry and more.
Last updated: October 11, 2019