Using precision genomics, Mayo researchers hope to develop improved medical laboratory tools for screening, diagnosing, and treating patients with inherited genetic disorders such as accelerated aging
Telomeres increasingly are on the radars of physicians and healthcare consumers alike, as researchers gain more knowledge about these critical nucleotides, and doctors continue to indicate their belief that telomeres could make useful diagnostic tools. If so, that would open up a new channel of precision medicine testing for clinical laboratories and anatomic pathology groups.
Telomeres are DNA strands that protect chromosome end points from degrading as people age. Their job is similar to the way plastic tips keep shoelaces from fraying, researchers at the Mayo Clinic explained in a news release. They have been using precision genomics in their assessment of 17 patients with short telomere syndrome (STS) to uncover the genetic causes of the condition.
They published their findings in the July issue of Mayo Clinic Proceedings.
Using Genetic Sequencing to Find Causes of Short Telomeres
People with STS could develop conditions including bone marrow failure, liver disease, and lung disease earlier in life than others, the news release pointed out.
However, according to the researchers’ paper, “Management of STSs is fraught with significant challenges such as delayed diagnoses, lack of routinely available diagnostics modalities, and standardized treatment guidelines.”
Nevertheless, some physicians are already leveraging information about telomeres in patient treatment. And many consumers have been turning to telomere diagnostic testing companies to learn the lengths of their own telomeres. They’ve learned that the longer the telomeres the better, as shorter telomeres are associated with accelerated aging.
More Study into STS is Needed
GenomeWeb summarized the Mayo study’s methodology as follows:
- “An analysis of data from 17 patients with STS confirmed by flow-FISH (fluorescence in situ hybridization) occurred;
- “Next-generation sequencing (NGS) was used on eight STS-related genes; and,
- “Exome sequencing was deployed to find suspicious germline alterations in participants who had short telomeres without STS variants.”
Researchers reported these findings in Mayo Clinic Proceedings:
- Six patients (35%) with genetic variations in the telomere complex;
- Four variants were known and involved: two telomerase reverse transcriptase (TERT) genes, one telomerase RNA component (TERC) gene, and one dyskerin (DKC1) gene; and,
- Two were of unknown significance in TERT and RTEL1
Study authors concluded that while some genetic mutations are common to short telomeres, they were found in only about 40% of the people in their study. So, more research is needed to discover other causes of short telomeres.
Telomeres and Lung Disease
Other research into telomeres was conducted by St. Paul’s Hospital and the University of British Columbia Department of Medicine, which focused on telomeres and lung disease.
In this study, researchers used polymerase chain reaction (PCR) to measure absolute telomere length from blood samples provided by 576 people with chronic obstructive pulmonary disease (COPD), according to a paper in the journal CHEST, published by the American College of Chest Physicians.
The study found that when compared to people with normal blood telomeres, people with shorter telomere lengths and more rapidly aging blood cells:
- Were 50% more likely to develop new or increasing respiratory symptoms;
- Were nine times more likely to die; and,
- Had worse health status and quality of life.
“It is known that short telomeres are associated with common morbidities of COPD, but it was not known if there is a relationship between blood telomeres and patient-related outcomes in COPD,” Don Sin, MD, a chest physician who led the research at the Centre for Heart Lung Innovation at St. Paul’s Hospital, stated in a news release.
Other Takes on Telomeres
A Harvard Medical blog noted, however, that short telomeres do not necessarily mean disease is imminent, nor that long ones guarantee optimal health.
“There is mounting evidence that a healthy lifestyle buffers your telomeres,” stated Immaculata De Vivo, PhD, a Harvard Medical School Professor and Genetics Researcher at the Dana-Farber/Harvard Cancer Center, in the blog post.
However, another expert questions the value of measuring telomeres for disease risk.
“In short, telomere lengths are too variable within a population, too variable within an individual, and too sensitive to environmental factors to offer any reliable information for common disease risk,” wrote Ricki Lewis, PhD, in PLOS.
Although there are many pitfalls to overcome, some doctors are pushing to use telomere information in patient treatment, and these studies from the Mayo Clinic and other researchers have contributed important data for diagnostic test developers.
In the end, vast and varied content about telomeres exists and clinical laboratory professionals may be called on to help clarify and assess the information. And that’s the long and the short of it.
—Donna Marie Pocius
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