Genetic Counseling and Genetic Testing: the Basics

What does a genetic counselor do?

Genetic counselors help patients with information about genetic diseases, and assist with making decisions about genetic testing and the results of genetic testing--medical screening that can detect heritable disease-related genotypes or mutations. They also help establish and interpret a family medical history in order to discover predispositions toward illness. They provide psychological support and referral for families with inherited diseases or at risk for an inherited disease.

What kinds of genetic testing are there?

Available tests include:

• newborn screening (routine tests for genetic disorders that can be treated early in life)
• diagnostic testing (used to rule out specific diseases that may be implied by a patient's symptoms)
• carrier testing (used to determine the chances of a couple passing on to a child the recessive genes that both parents carry
• prenatal testing (screening a fetus for genetic or chromosomal disorders)
• predictive and presymptomatic testing (used by adult patients when there is a strong family history of a disease that might develop later in life, such as breast cancer)
• susceptibility tests (genetic markers that in combination suggest slightly high or lower than average risks for common disorders)
• identity testing (using DNA to identify a person, usually in paternity suits or in criminal (forensic) cases)

What does a genetic medical history tell a person?

A medical family history taken by a genetic counselor can help people decide if they should consider genetic testing or make lifestyle changes or seek preventive medical care based on the diseases that have been prevalent in their relatives. It is important to note that testing positive for a gene variant is not a guarantee that a person will get that disease. If both of your parents have Type 2 diabetes, for example, and you test positive for the gene variant, you may make preventive changes to your lifestyle and avoid the illness.

How much does a genetic test cost?

The cost can range from $100 to thousands of dollars, depending on the type of test. If tests are recommended by your doctor, they will most likely be covered by health insurance.