One in 25 Irish people are at risk of developing chronic obstructive pulmonary disease (COPD) due to a combination of inherited genes and exposure to cigarette smoke, a new study has found.
The study, by researchers from the Alpha One Foundation, the Royal College of Surgeons (RCSI) and Harvard University, is published this month in the American Journal of Respiratory and Critical Care Medicine.
The debilitating lung condition is linked to alpha-1 antitrypsin deficiency (alpha-1), an inherited condition affecting almost 250,000 people in this country.
Alpha-1 antitrypsin is a protein which protects the lungs and people with lower than normal amounts of this protein are at an increased risk of developing COPD.
The research proves for the first time that the estimated one in 25 people in Ireland who have inherited a combination of one normal (M) and one abnormal (Z) alpha-1 antitrypsin gene have an increased risk of developing the condition.
Prior to this study, the increased risk of developing COPD as a result of alpha-1 deficiency was only definitively known to affect people who inherit two abnormal (ZZ) alpha-1 genes.
Cigarette smoke is the most influential factor in determining whether people who carry this combination of genes (MZ) are at a greater risk of COPD compared to those who have two normal alpha-1 genes (MM).
Doctors leading the research are urging people diagnosed with COPD - an estimated 440,000 people - to get tested for alpha-1 antitrypsin deficiency through a free national screening programme.
Professor Gerry McElvaney, Professor of Medicine at RCSI, principal investigator and chairman of the Alpha One Foundation Ireland said the research was a major breakthrough in understanding the heightened risk of COPD for people with have the combination of one normal and one abnormal alpha-1 antitrypsin gene.
“If people know that they have a genetic predisposition to developing COPD, it allows intervention at an earlier age, encourages smoking cessation and prevents a further decline in lung function in a disease that is otherwise preventable. It also provides an opportunity for other family members to get tested for alpha-1.”
Dr. Kevin Molloy, Royal College of Surgeons in Ireland, the lead author of the study said Alpha-1 deficiency is massively underdiagnosed both in Ireland and internationally.
“As this research has an impact on a large number of people who have the MZ gene combination, the research will greatly increase awareness and diagnosis of alpha-1. Knowing that you have a genetic predisposition to developing COPDshould e ncourage people to avoid exposure to cigarette smoke if they definitively know they have a higher risk of developing this debilitating lung condition.”
The alpha-1 screening programme is funded by the Department of Health and Children and run by the Alpha One Foundation. It can be diagnosed by a simple blood test.
For more information on how to be tested contact the National Centre for Alpha-1 at Beaumont Hospital or visit www.alpha1.ie