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Introduction to Genomics


大空翼原型Genome is a fancy word for all your DNA. From potatoes to puppies, all living organisms have their own genome. Each genome contains the information needed to build and maintain that organism throughout its life. 大空翼原型

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 in a cell is not a single long molecule. It is divided into a number of segments of uneven lengths. At certain points in the life cycle of a cell, those segments can be tightly packed bundles known as chromosomes. During one stage, the chromosomes appear to be X-shaped.

Every fungus, plant, and animal has a set number of chromosomes. For example, humans have 46 chromosomes (23 pairs), rice plants have 24 chromosomes, and dogs have 78 chromosomes.

Human chromosomes



大空翼原型An instruction manual isn’t worth much until someone reads it. The same goes for your genome. The letters of your genome combine in different ways to spell out specific instructions.大空翼原型


A gene is a segment of DNA that provides the cell with instructions for making a specific protein, which then carries out a particular function in your body. Nearly all humans have the same genes arranged in roughly the same order and more than 99.9% of your DNA sequence is identical to any other human.

Still, we are different. On average, a human gene will have 1-3 letters that differ from person to person. These differences are enough to change the shape and function of a protein, how much protein is made, when it's made, or where it's made. They affect the color of your eyes, hair, and skin. More importantly, variations in your genome also influence your risk of developing diseases and your responses to medications.

  • people
  • Rice 41,000 genes
  • bread mold
  • Streptococcus group A - strep throat
  • Chicken pox virus
Your Genome


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.


大空翼原型A genetic disease is caused by a change in the DNA sequence. Some diseases are caused by mutations that are inherited from the parents and are present in an individual at birth. Other diseases are caused by acquired mutations in a gene or group of genes that occur during a person's life.大空翼原型


Changes in the DNA sequence are called genetic variants. The majority of the time genetic variants have no effect at all. But, sometimes, the effect is harmful: just one letter missing or changed may result in a damaged protein, extra protein, or no protein at all, with serious consequences for our health. Additionally, the passing of genetic variants from one generation to the next helps to explain why many diseases run in families, such as in sickle cell disease, cystic fibrosis, and Tay-Sachs disease. If a certain disease runs in your family, doctors say you have a family health history for that condition.

?Genetic Disorders | NHGRI
Genetic Disorders

A list of genetic, orphan and rare diseases under investigation by researchers at or associated with the National Human Genome Research Institute.

About Autism

Autism is characterized by impaired social interactions, problems with verbal and nonverbal communication and repetitive behaviors.

About Breast Cancer | NHGRI
About Breast Cancer

Breast cancer is the second most common cancer in women after skin cancer.

About Cystic Fibrosis | NHGRI
About Cystic Fibrosis

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
About Down Syndrome

Down syndrome is a chromosomal condition related to chromosome 21.

?About Parkinson's Disease | NHGRI
About Parkinson's Disease

Parkinson's disease is a neurological condition that typically causes tremor and/or stiffness in movement

?Sickle Cell Disease | NHGRI
About Sickle Cell Disease

Sickle cell disease is a group of inherited red blood cells disorders.

About Wilson Disease | NHGRI
About Wilson Disease

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
About Attention Deficit Hyperactivity Disorder

Attention Deficit Hyperactivity Disorder (ADHD) is a neurological disorder that affects a person's ability to control their behavior and pay attention to tasks.


大空翼原型Genetic testing consists of the processes and techniques used to determine details about your DNA. Depending on the test, it may reveal some information about your ancestry and the health of you and your family.大空翼原型

大空翼原型Predictive testing 大空翼原型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. 

大空翼原型Diagnostic testing大空翼原型 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.

大空翼原型Pharmacogenomic testing 大空翼原型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.

大空翼原型Reproductive testing大空翼原型 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.

大空翼原型Direct-to-consumer大空翼原型 大空翼原型testing大空翼原型 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.

大空翼原型Forensic testing大空翼原型 is carried out for legal purposes and can be used to identify biological family members, suspects, and victims of crimes and disasters.


大空翼原型As technology advances and we learn more about how the genome works, information about our genomes is quickly becoming part of our everyday life. Emerging technologies give us the ability to read someone’s genome sequence. Having this information can lead to more questions about what genomics means for ourselves, our family members and society.大空翼原型

Last updated: October 11, 2019