New study offers insights on genetic indicators of COPD risk

January 16, 2018, NIH/National Heart, Lung and Blood Institute
Top: Standard central airway anatomy with medial basal airway present (red arrow). Bottom: Absent medial basal airway variant (red circle) Credit: Eric A. Hoffman, University of Iowa, MESA Lung/SPIROMICS Radiology Ready Center

Researchers have discovered that genetic variations in the anatomy of the lungs could serve as indicators to help identify people who have low, but stable, lung function early in life, and those who are particularly at risk for chronic obstructive pulmonary disease (COPD) because of a smoke-induced decline in lung function. The results of the study, which was funded by the National Heart, Lung and Blood Institute (NHLBI), appear this week in the journal Proceedings of the National Academy of Sciences.

Cigarette smoking has long been the most common cause of COPD, but not all smokers develop the condition, and many non-smokers do. Why that is so has never been fully understood, but a team of researchers now have a clue after discovering that genetically programmed tree variation is linked to a higher prevalence of COPD among .

"This work raises many interesting questions for researchers. Understanding precisely why these genes influence the development of COPD may lead to entirely new and more effective ways of preventing or treating this disease," said James Kiley, M.D., director of the NHLBI Division of Lung Diseases. "This novel study suggests that a CT scan, which is widely available, can be used to measure airway structure and predict who is at higher risk for smoke-induced lung injury."

COPD, a progressive disease that makes it hard to breathe, is the fourth leading cause of death in the United States. An estimated 16 million people are currently diagnosed with COPD, and millions more are believed to have the condition.

Micrograph showing emphysema (left – large empty spaces) and lung tissue with relative preservation of the alveoli (right). Credit: Wikipedia

Until recently, researchers believed that COPD developed later in life as a result of prolonged exposure to cigarette smoke or air pollution, which accelerated the decline in . However, recent studies have shown that many older adults with COPD had low lung function early in life and experienced the normal associated with aging, not an accelerated decline.

"In the current study, we found that central airway branches of the lungs, which are believed to form early in life, do not follow the textbook pattern in one quarter of the adult population and these non-textbook variations in airway branches are associated with higher COPD prevalence among older adults," said the study's first author Benjamin M. Smith, M.D. M.S., assistant professor at Columbia University Medical Center. "Interestingly, one of the airway branch variants was associated with COPD among smokers and non-smokers. The other was associated with COPD, but only among smokers."

These airway tree variations are identifiable on low-dose screening CT scans, which are currently indicated clinically for in older patients with a history of heavy smoking in the prior 15 years. Before CT scans are used outside of this group for the identification of airway variants in clinical practice, the study authors say more research will be needed to confirm that preventive or therapeutic interventions based on the presence of airway tree variations can improve patients' outcomes.

In the meantime, the researchers say they will be investigating another important finding—this one around family history. Their study identified a common airway branch variation that occurs within families and is associated with COPD among non-smokers. Smith said while other developmental events that occur within families may be involved, his research team is looking into whether there is a genetic basis for this variant. "If proven," he said, "this would represent a novel mechanism of COPD among non-smokers."

The researcher emphasized that for all the new findings, quitting smoking remains the best antidote to COPD, and smokers trying to quit should seek professional help, if necessary, to succeed.

Explore further: Study reveals surprises concerning COPD and smoking

More information: Benjamin M. Smith el al., "Human airway branch variation and chronic obstructive pulmonary disease," PNAS (2018). www.pnas.org/cgi/doi/10.1073/pnas.1715564115

Related Stories

Study reveals surprises concerning COPD and smoking

March 22, 2017
A new study challenges the widely accepted but oversimplified description of airway inflammation in smokers and patients with chronic obstructive pulmonary disease (COPD).

Loss of airway blood vessels is associated with risk of death in smokers without COPD

May 23, 2017
In a new study, CT-measured vascular pruning - the diminution of distal pulmonary blood vessels (vessels on the outer edges of the lungs) - was associated with increased risk of death in smokers without chronic obstructive ...

Downregulation of miR-126 augments DNA damage response

August 2, 2017
(HealthDay)—For cigarette smokers and patients with chronic obstructive pulmonary disease (COPD), downregulation of microRNA-126 (miR-126) augments DNA damage response (DDR), according to a letter to the editor published ...

Uncovering genetic links to the development of pulmonary disease

March 6, 2017
Building on EU-funded research, scientists have identified genetic traits that heighten the risk of developing chronic obstructive pulmonary disease.

Quit-smoking drug safe for lung disease patients

May 10, 2017
Medication that helps smokers to quit is safe for use by people with chronic lung conditions, research suggests.

COPD heightens deadly lung cancer risk in smokers

September 25, 2015
Smokers who have chronic obstructive pulmonary disorder (COPD) may face nearly twice the risk of getting small cell lung cancer (SCLC)—the deadliest form of lung cancer—than smokers who don't have COPD, according to a ...

Recommended for you

Small-scale poultry farming could mean big problem in developing countries

December 16, 2018
Small-scale farming in developing countries provides those in rural communities with income and access to protein, but it may have a large impact on antibiotic resistance, according to a new University of Michigan study.

RNA processing and antiviral immunity

December 14, 2018
The RIG-I like receptors (RLRs) are intracellular enzyme sentries that detect viral infection and initiate a first line of antiviral defense. The cellular molecules that activate RLRs in vivo are not clear.

Faster test for Ebola shows promising results in field trials

December 13, 2018
A team of researchers with members from the U.S., Senegal and Guinea, in cooperation with Becton, Dickinson and Company (BD), has developed a faster test for the Ebola virus than those currently in use. In their paper published ...

Urbanisation and air travel leading to growing risk of pandemic

December 13, 2018
Increased arrivals by air and urbanisation are the two main factors leading to a growing vulnerability to pandemics in our cities, a University of Sydney research team has found.

Drug targets for Ebola, Dengue, and Zika viruses found in lab study

December 13, 2018
No drugs are currently available to treat Ebola, Dengue, or Zika viruses, which infect millions of people every year and result in severe illness, birth defects, and even death. New research from the Gladstone Institutes ...

Researchers discover new interactions between Ebola virus and human proteins

December 13, 2018
Several new connections have been discovered between the proteins of the Ebola virus and human host cells, a finding that provides insight on ways to prevent the deadly Ebola virus from reproducing and could lead to novel ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.