Autoimmunity plays a key role in the development of chronic obstructive pulmonary disease (COPD), a new study has shown.
COPD is a group of lung diseases that cause airflow blockage and breathing related problems, which includes emphysema and bronchitis.
Genome-wide association studies have already identified several genes that contribute to the development of COPD, but scientists still lack a complete understanding of the pathogenesis of this disease.
"Our findings suggest that future research should target the role of the immune system in the pathogenesis of COPD. Understanding this relationship may help to elucidate the biological mechanisms that contribute to the development of COPD," the researchers reported in the paper published in the American Journal of Respiratory Cell and Molecular Biology.
They found that single nucleotide polymorphisms (SNPs) that represent a difference in a single DNA building block, called a nucleotide, and are the most common type of genetic variation among people with COPD.
A specific SNPs rs2074488, is positively associated with COPD and is linked to the HLA-C gene, which presents a protein to B or T immune cells to kill bacteria or viruses, making COPD similar to autoimmune disease, the researchers explained.
"This SNP is also associated with several autoimmune diseases, like Type-1 diabetes and rheumatoid arthritis, which suggests a genetic link between autoimmune disease and COPD. Many years ago, people believed that one of the causes of COPD is because the autoimmune system attacks its own lungs. We kind of confirmed that by our big data," said Xiangming Ji, Assistant Professor at Georgia State University.
"People are genetically very similar, a major difference is because of this SNP. This could be changed by the environment also. So some people with a specific SNP are more prone to get this disease," Ji added.
In the study, the team performed a phenome-wide association study (PheWAS) of 16 previously reported COPD-associated SNPs and included data from 18,335 adults of European descent.
The researchers identified 1,805 COPD cases.