Mutations in telomere genes may cause pulmonary fibrosis, emphysema and impact life expectancy, according to new research results.
Telomeres are found at the end of chromosomes, where they act like a protective tip. When cells divide, telomeres shorten. Over the lifespan, with multiple cell division and aging, telomeres get shorter.
Eventually telomeres become so short that the cell dies, causing disease. Lengthening telomeres is not a magic bullet leading to eternal youth, either, since doing so can in fact lead to cancer.
Brigham Young University biologist Jonathan Alder has been studying these DNA ends attached to our chromosomes, finding that shorter telomeres may predict a shorter lifespan and also specific lung diseases.
“This a definite goldilocks situation,” Alder said. “Too little, you age prematurely; too much, you could get more serious diseases. You need to be just right.”
Alder wants to understand which specific gene mutations cause particularly short telomeres. Recent research, published in the Journal of Clinical Investigation and Chest, reported that those mutations are associated with pulmonary fibrosis and emphysema.
According to Alder, an assistant professor of physiology and developmental biology at BYU, “When we are born, our telomeres are longer. As you get older, they shorten. What we have found is that if you look at individuals with lung disease, they have shorter telomeres than the rest of us.”
The scientists found that proportion of those people (although not everyone) who develop severe emphysema have mutations in genes that control telomeres. Smoking increases the risk of emphysema in people who already have telomere mutations. Mutations in telomere genes are already known to cause pulmonary fibrosis. The results therefore show that the two diseases may share a common cause, even though they were previously believed to be unassociated.
The mutations could also be passed down through generations.
“Families with telomere mutations pass those down the line, meaning offspring start off with shorter telomeres,” stated Alder. “With each passing generation the disease gets worse and they get it at an earlier age.”
Lead researcher Mary Armanios, associate professor of oncology at John Hopkins University School of Medicine, added “Most people don’t realize that lung disease is the third most common cause of death in the United States. Telomere research has its most significant direct public health benefit in the area of lung disease.”
Ultimately, telomere research may provide directions for the treatment of lung diseases, such as pulmonary fibrosis and emphysema.