Genetic counseling: Answers to common questions

Allison Gregory, MS, CGC

What is a genetic counselor?
Genetic counselors are health care professionals with experience in the areas of clinical genetics and counseling. Most have a master's degree from one of several training programs in the United States, and many are certified by the American Board of Medical Genetics or the American Board of Genetic Counseling. Counselors frequently specialize in an area of genetics, such as prenatal or cancer genetics.

Genetic counselors provide information and support to those who have family members with birth defects or genetic disorders and to families who may be at risk for a variety of inherited conditions. Genetic counselors identify individuals and families at risk for genetic conditions, analyze inheritance patterns, assess risks, coordinate specialized testing, and communicate information so that individuals and families can make informed decisions about their genetic health care. They often serve as a patient advocate and refer individuals and families to other appropriate resources. Genetic counselors also frequently play roles as educators and engage in research activities.

What can you expect during a genetic counseling session?
The first step of genetic counseling usually involves collecting detailed information about the family history. Many genetic counselors will draw a family tree, or pedigree, to document this information and show relationships. If a pregnancy is involved, then the pregnancy history, such as medications taken or complications experienced, will also be reviewed.

Based on the information collected, the genetic counselor will perform genetic risk assessment and explain the findings in clear terms. It is the job of the counselor to explain medical conditions, risks for genetic conditions, and genetic testing in a manner that is easy to understand. When appropriate, the counselor may explain a genetic test or medical procedure to patients. The risks and benefits of these should be discussed, and it is always the choice of the patient to accept or decline testing.

Following a genetic counseling appointment, the counselor will frequently coordinate recommended testing with a patient's physician. Test results and further recommendations can be explained to the patient by the referring physician and the genetic counselor with the input of a physician geneticist when appropriate, so that the patient feels that she/he clearly understands the results and their implications.

In the event that a patient has an abnormal genetic test result or requires further testing, she/he typically has another meeting with the genetic counselor, sometimes in conjunction with a physician geneticist. The counselor explains the abnormal test results and options to the patient.

Would you benefit from genetic counseling?
Many women are referred for genetic counseling during pregnancy. Some of the common reasons for such counseling include:

Advanced maternal age: Women who are 35 years of age or older at the time of delivery have an increased risk to conceive a pregnancy with a chromosome abnormality.

Positive maternal serum marker screen: This is often called an AFP or triple marker test. Women with a positive result have an increased risk for one or more birth defects and should be offered genetic counseling.

Family history: There may be someone in the family with a condition that may be genetic, such as mental retardation, birth defects, or cancer.

Medication or recreational drug exposure: When taken during pregnancy, some of these increase the risk for birth defects.

Maternal virus/infection: When a pregnant woman has a virus such as cytomegalovirus, parvovirus B19, or rubella, there is an increased risk for the fetus to also contract the virus, which may cause certain birth defects.

Maternal conditions: When the mother has conditions such as diabetes or seizures, there may be an increased risk for certain birth defects.

Infertility or multiple miscarriages: These have many causes, both genetic and nongenetic.

Abnormal ultrasound findings: When a variation or abnormality is seen, genetic counseling may be offered to review information and consider additional testing options.

Ethnicity: Some ethnic groups have an increased risk for certain genetic traits or conditions and may be offered screening during pregnancy.

Consanguinity: This refers to situations in which members of the couple are related by blood, such as cousins. Depending on the degree of the relationship, there may be an increased risk for birth defects, and genetic counseling is indicated.

Most expectant parents have passing worries about the health of their baby. These fears are normal, and often unfounded. But when you or your provider have real reason for concern, a genetic counselor can help you understand more about conditions and risk factors that may affect your baby.