Cystic Fibrosis

Cystic fibrosis is an inherited disorder that causes mucus to build up and damage many of the organs in the body. CF particularly affects the lungs and pancreas. This causes chronic lung infections with difficulty breathing and digestive problems. Symptoms and severity can vary depending on the pathogenic variants present in a person. Death due to complications of CF can vary from childhood well into adulthood. CF is caused by pathogenic variants in the CFTR gene.

CF is inherited in an autosomal recessive manner. This type of inheritance requires the presence of two copies of a pathogenic variant in the gene for a person to have the genetic disease. Both parents must be carriers of a pathogenic variant in the gene in order to be at risk to have an affected child. The child must inherit a pathogenic variant from each carrier parent in order to be affected. There is a 1 in 4 chance that a baby will inherit two mutated copies of the gene and be affected when both parents are carriers.

There are generally no signs or symptoms associated with being a carrier for CF. However, the risk to have a child affected with CF is increased, especially for certain ethnicities. Testing of reproductive partners is recommended for carriers of CF.

CF is more common in the Caucasian (white) and Ashkenazi Jewish populations and less common in other ethnic groups. CF occurs in about 1 in 2,500 Caucasian newborns and 1 in 2300 newborns of Ashkenazi Jewish descent. Cystic fibrosis is less common in other ethnic groups, with 1 in 17,000 African Americans and 1 in 31,000 Asian Americans newborns born with CF.

Genetics Home Reference: Cystic fibrosis (http://ghr.nlm.nih.gov/)
Genetic Alliance: Cystic fibrosis (http://www.diseaseinfosearch.org/)

OMIM [Cystic fibrosis: 219700] (http://www.ncbi.nlm.nih.gov/omim)
Gene Reviews: CFTR-related disorders (http://www.ncbi.nlm.nih.gov/books/NBK1116/)

• Full gene sequencing
• Copy number analysis: exons 2 & 3