Cystic fibrosis is a disease that causes thick, sticky mucus in the lungs, pancreas and intestines. Common problems associated with cystic fibrosis include lung infections and difficulty absorbing nutrients from the digestive tract. People with cystic fibrosis live an average of 30 years. No cure exists.

The disease is inherited. Symptoms only appear if a person has two copies of the abnormal gene that causes cystic fibrosis — one from the mother and one from the father. If a person has only one abnormal gene then he or she is a "carrier" but would not have symptoms. Children of parents who have no symptoms can still have cystic fibrosis but only if both parents contribute the abnormal gene to their baby. The chance that someone is a carrier without symptoms depends on his or her ethnic background, shown here:

Ethnic Group	Chance of Carrying the Abnormal Cystic Fibrosis Gene
Ashkenazi Jewish	1 in 29 people	3.4 %
Other Caucasian	1 in 29	3.4 %
Hispanic	1 in 46	2.2 %
African American	1 in 62	1.6 %
Asian American	1 in 90	1.1 %

The risk of a child having cystic fibrosis because both parents carry the gene can be estimated based upon the risks noted above. If both partners are of the same ethnic background, the risk for having an affected child is:

Ethnic Group of Parents	Chance of Having a Child with Cystic Fibrosis Disease
Askkenazi Jewish	1 in 3,300 offspring	0.03 %
Other Caucasian	1 in 3,300	0.03 %
Hispanic	1 in 8,464	0.01 %
African American	1 in 16,900	0.006 %
Asian American	1 in 32,400	0.003 %

A simple blood test can detect many, but not all of the genetic abnormalities that cause cystic fibrosis (there are more than 300 abnormalities). The chance that the blood test will accurately find a gene abnormality depends on the ethnic background of the person being tested:

Ethnic Group of Parents	Chances that test would find a Cystic Fibrosis Gene	Chances that test would not find a Cystic Fibrosis Gene
Askkenazi Jewish	90 in 100 (90 %)	10 in 100 (10 %)
Other Caucasian	80 in 100 (80 %)	20 in 100 (20 %)
Hispanic	57 in 100 (57 %)	43 in 100 (43 %)
African American	69 in 100 (69 %)	31 in 100 (31 %)
Asian American	Data not available	Data not available

The American College of Obstetrics and Gynecology recommends screening for couples who are currently pregnant or are actively planning a pregnancy. Testing is done for those at higher risk of being cystic fibrosis carriers, including Ashkenazi Jews or other Caucasians. Usually the woman is tested first. If she does not carry the abnormal cystic fibrosis gene, then her chances of passing on that abnormalityto abnormality to her child are very low. Her partner would not need testing. If the woman does carry the trait, then her partner should also be tested.

If both partners carry the cystic fibrosis genes, the risk of their baby having cystic fibrosis is 1 in 4 (25%). Prenatal testing (amniocentesis) would be recommended to see if the fetus has cystic fibrosis. During amniocentesis, some of the fluid surrounding the fetus is obtained through a needle. This fluid contains some of the baby's cells that can be tested for the cystic fibrosis genes.

You may have the genetic test for cystic fibrosis through our laboratory. Your doctor can order this test for you. Some patients may have special circumstances or questions, and may want to meet with a genetic counselor to decide whether or not to have the blood test. If you have any other questions, please speak with your doctor.

Insurance coverage for the cystic fibrosis test may vary. Please check with your insurance carrier to see if it is a covered benefit or not. Our office can help you with this.