The DNA strands on the end of chromosomes, called telomeres, are great predictors of life expectancy, stated BYU biologist Jonathan Alder. He claims that the shorter your telomeres, the shorter your lifespan.
But that's not the only thing these fascinating strands of DNA predict. Shorter telomeres also indicate a greater chance for bone marrow failure, liver disease, skin disease and lung disease.
Alder was currently studying the gene mutations that cause people to have unnaturally short telomeres. Recent research he coauthored with collaborators at Johns Hopkins University found those mutations are connected to both pulmonary fibrosis and emphysema.
Telomeres are the protective tip of our chromosomes, kind of like the plastic cap on the end of a shoelace. Each time a cell divides and replicates, the DNA at the end of telomeres shorten. Since cell division happens throughout life, telomeres get shorter and shorter as we age.
When the telomeres run out, the cell becomes inactive or dies, which leads to disease. Some scientists have figured out ways to lengthen telomeres, but that wasn't the magic bullet either: telomeres that keep their length could lead to other complications like cancer.
The findings from the research team on emphysema, one of the leading causes of death in the U.S. are particularly important. The researchers found that a fraction of individuals who develop sever emphysema have mutations in one of the genes responsible for maintaining telomeres. Since mutations in telomere genes are known to cause pulmonary fibrosis, these findings link two diseases that were previously thought to be unrelated.
While only people with very short telomere length are at greater risk for lung diseases, finding the connection was unexpected. Alder's research on the matter, which started at Johns Hopkins and has continued here at BYU, will now focus on why it was happening.