Does Genetics play a role in COPD (Chronic Obstructive Pulmonary Disease)?
There are many known factors contributing to the development of COPD such as race, ethnicity, gender and environmental factors. However, many people do not realize that genetics can also play a significant role.
Scientists have discovered a gene called SERPINA1 that is located on chromosome 14 and is responsible for producing a protein called alpha-1 antitrypsin (AAT). This is a protease inhibitor that inhibits neutrophil elastase (NE), which protects elastic tissue from being destroyed. Mutations in the SERPINA1 gene can lead to a deficiency in alpha-1 antitrypsin (“α1-antitrypsin”). These mutations can be inherited from parents and lead to significant problems in both the lungs and liver such as:
- Early onset emphysema (<45 years old)
- Unexplained bronchiectasis or other lung disease
- Necrotizing panniculitis (group of diseases associated with the inflammation of subcutaneous adipose tissue)
- Unexplained liver disease
- Vaculitis associated with a positive C-ANCA (antineutrophil cytoplasmic antibody)
Common SIGNS and SYMPTOMS of α1-antitrypsin (AAT) deficiency are:
- Shortness of breath
- Chronic cough
- Excess in sputum production
- Recurrent chest colds
- Eyes and skin turning yellow (jaundice)
- Swelling of the abdomen (ascites)
- Vomiting of blood or passing blood in the stool
Symptoms commonly begin between the ages of 20-50 years old.
What is the PREVALANCE of α1-antitrypsin (AAT) deficiency?
It is currently known that α1-antitrypsin (AAT) deficiency affects about 1 in 1,500-3,500 individuals with European ancestry. As much as 5% of COPD diagnosed is expected to be caused by α1-antitrypsin (AAT) deficiency. However, many people are not tested and, therefore, the prevalence could be much higher than documented.
Is there TREATMENT available?
While α1-antitrypsin (AAT) deficiency isn’t curable, it is treatable through intravenous augmentation (replacement) therapy. The alpha-1 antitrypsin protein can be taken from the blood plasma of healthy human donors and used to create infusions that are usually needed by the recipient weekly. This may be accompanied by bronchodilators, antibiotics when appropriate, immunization protocols, oxygen as needed, fitness programs and plans for decreasing environmental exposures that can continue to elevate risks.
α1-antitrypsin (AAT) deficiency is inherited and can only be prevented when there is the knowledge of a parent carrying a mutation of SERPINA1. However, once diagnosed, people can decrease the severity of the disease by avoiding environmental factors known to worsen the disease, such as cigarette smoking.
The goals of therapy are to improve symptoms and decrease or stop the progression of damage to the lungs and liver. These goals can only be accomplished with ongoing treatment until a cure is discovered.
Who should be considered for GENETIC TESTING for α1-antitrypsin (AAT) deficiency?
NCFDNA offers RespiraGene, a genotype test that can be used to determine what SERPINA1 alleles are present.
There are over 120 mutations of the SERPINA1 gene that have been identified. Some cause disease and others do not. NCFDNA genetic testing can detect the most common mutations that have been associated with the development of disease. This can be helpful to:
- Determine if signs and symptoms of lung or liver disease have a genetic origin and can be treated more effectively
- Distinguish between the different types of variants
- Help patients currently affected by disease caused by SERPINA1 mutations in making decisions about reproduction