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Every person is born with their own unique set of genes, the “blueprints” that affect how their body looks and functions. These blueprints are contained in your DNA. DNA is long, spiral-shaped molecules found inside every cell in your body. DNA carries your genetic information or genes. These genes are passed down from generation to generation.

Genetics is the study of how certain traits, such as the risk for some diseases, are inherited or passed down from parents to their children. Thanks to advances in medical research, doctors now have the tools to understand how problems with genes cause or increase the risk for many illnesses.

Some diseases are caused by a problem with a gene or genes that your child gets from one or both parents. Examples of genetic diseases that can be passed down in families include cystic fibrosis and sickle cell anemia. Other diseases are caused by a gene that changes inside your child’s body, instead of problems with the genes they inherited. Many childhood cancers are caused by this type of genetic change.

Things You Need to Know

Genetic testing can help doctors detect some abnormalities in your child’s genes, groups of genes called chromosomes [kroh-muh-sohmz], and the products genes make (proteins). Genetic testing can be performed before a baby is born and is often offered to pregnant women. These tests can be done using blood samples, ultrasound imaging, or a procedure called amniocentesis [am-nee-oh-sen-tee-sis] that involves taking a small amount of the fluid that surrounds a baby in the womb. Talk with your doctor about the risks and benefits of these tests and what sorts of information they can give you.

All babies born in the United States have genetic testing for a condition called phenylketonuria (PKU), a rare genetic disorder. PKU can cause learning disabilities, seizures, and other problems. The test is performed shortly after birth.

When to See a Doctor

If you have questions about genetic testing, be sure to discuss them with your doctor. You may be referred to a genetic counselor. Genetic counselors are specialists who can help you assess your baby’s risk for genetic disorders.