By Dr. Brandon Colby MD, a physician-expert in the fields of Genomics and Personalized Preventive Medicine.
If you’re interested in genomics, science, and biology, you may have read a few articles on the importance of telomeres. But what do you think these structures are?
Telomeres are genetic structures formed by short genetic sequences that are located at the ends of chromosomes. These structures have a specific nucleotide sequence that is repeated several times, and they act by preventing our chromosomes from becoming damaged or fused with other chromosomes.
Imagine the tiny plastic caps that can be found at the end of most shoelaces — telomeres are the caps that protect the terminal portions of our chromosomes from fraying or getting tangled. They even have a “loop” or knot at the end, called a T-loop, which is stabilized by a group of proteins called the shelterin complex.
But telomeres fulfill other important roles that have a significant impact on the aging process. You see, when DNA is replicated during cell division, a few nucleotides are “lost” each time. A telomere is a non-coding sequence that consists of the same six nucleotides over and over again; as our DNA replicates itself throughout the course of our lives, these repetitive sequences become shorter to protect the rest of our DNA.(#1-What is a telomere) Telomere shortening allows the rest of our DNA sequence to continue replicating normally.
An enzyme called telomerase continuously restores and adds more base pairs to a telomere, but they eventually become shorter. Telomeres and telomerase were discovered by researcher Elizabeth Blackburn, who won the Nobel Prize in Physiology or Medicine in 2009 for this discovery. Telomerase is most active in cells that replicate quickly and often, including:
- Hematopoietic or blood cells
- Stem cell populations
- Activated lymphocytes
Additionally, telomerase has been found to be more active than normal in cancer cells, allowing them to continue replicating rapidly once they have become malignant.
As a natural result of this process, each telomere becomes progressively shorter with each cell replication. Once they reach a certain length, they unfold, at which point the cell becomes unable to keep replicating itself and becomes senescent. After reaching senescence, cells either start to accumulate damage or eventually die. When the telomere unfolds or becomes “uncapped”, it’s also possible for apoptosis — programmed cell self-destruction — to occur.
These genetic structures send signals when the DNA in the chromosome that they’re protecting becomes dangerously short. When this happens, it’s necessary for DNA to be repaired rather than replicated in order to prevent errors in cell division which can increase a patient’s risk for cancer, cardiovascular disease, and other conditions related to the aging process.(#2-What are telomeres)
Now that you know this, it will probably come as no surprise to learn that the length of your telomeres plays a significant role in the aging process. Telomeres will naturally become shorter as we age, of course, but accelerated shortening causes our cells to age faster. Short telomeres can also result in genomic instability, improper recombination, chromosome loss, and abnormal translocations.
If having longer telomeres can affect your health so significantly, it makes sense that you’d want to discover whether your telomeres are short, normal, or long for your age. But how are you supposed to do this?
Thanks to science, we are now able to determine the length of an individual’s telomeres thanks to modern genetic analyses, such as high-throughput PCR. Shorter telomeres have been associated with a shorter lifespan, poor survival, and an increased incidence of certain conditions.(#3-Telomeres and lifestyle) Therefore, testing the length of your telomere can be a very useful tool in order to assess your present and future health, and determine whether you need to make lifestyle changes to improve the health of your cells and prevent premature aging.
Published studies have found that certain biomarkers for telomere shortening increase with biological age and age-related diseases, serving as a possible indicator of a patient’s longevity.
Our telomere length at birth and the rate at which they will shorten throughout our lives varies widely between different individuals. Different lifestyle and environmental factors can affect telomere length.(#4-Longevity Prediction)
Telomere length testing is still a relatively new technology, and only a few companies offer it. Some companies only provide tests to individuals who want to confirm whether they have genetically short telomeres, rather than to the general public.
Certain companies, such as Sequencing.com, provide direct-to-consumer testing kits for telomere length measurement, whereas others, such as SpectraCell, require a doctor’s prescription.
Telomere tests work by determining your average telomere length based on samples taken from peripheral blood cells. This average length is then compared to a database of percentile telomere lengths in other people who are in the same age group as you. Through this process, they are able to determine whether you have shorter or longer telomeres than expected according to your age.
Different techniques can be used to measure telomere length. One of the first technologies used for telomere testing was terminal restriction fragmentation, which is highly accurate.(#5-Telomere Length) Other technologies used for telomere length measurement include:
Whole genome sequencing (WGS) is the most advanced technology for determining the length of your telomeres. This technology sequences your entire genome, which includes all 30,000 genes as well as all chromosomes end-to-end. Since the chromosomes are fully sequenced, the telomeres at the ends of each chromosome are also sequenced.
In addition to using WGS to obtain the length of your telomeres, once you’ve had your whole genome sequenced you can then analyze your genes for almost any other purpose including health, rare disease screening, wellness, genealogy, and self-discovery.
Because using WGS to determine telomere length and biological age is so new, it’s only offered by Sequencing.com. Learn more about Sequencing.com’s Ultimate DNA Test.
This type of telomere analysis has many other applications in medicine and science, such as:
- Detection of genetic disorders
- Longevity medicine
- Preventive healthcare
- Mutation detection
- Paternity testing
Real-time polymerase chain reaction, also known as quantitative PCR or qPCR, is based on amplifying your DNA and uses fluorescence techniques to identify its telomere length.(#6-qPCR Telomere Test) This technique has a relatively low-cost and high reproducibility when compared to other telomere test technologies, which is one of the reasons for its rising popularity.
This is currently the most commonly used type of analysis to tell your telomere length. PCR can also be used for diagnosing COVID-19 infections.
Another technique is known as Flow FISH telomere test. This technique is based on two different technologies: fluorescent in situ hybridization (FISH) and flow cytometry. In Flow FISH telomere testing, leukocytes are isolated from a blood sample and mixed with fluorescent peptide nucleic acid (PNA) probes that are designed to attach to telomere base pair sequence repeats (TTAGGG).
Then, the level of resulting fluorescence in the DNA is measured to determine the median telomere length. FlowFISH is most commonly used for research purposes, although some companies have started to offer this as a commercial analysis under a physician’s prescription.
This technique is different from the previous ones because it measures the length of specific telomeres rather than your average telomere length. However, clinical studies have found that even a single critically short telomere can affect your disease risk and longevity. But if an individual only has one critically short telomere while the rest are normal, then test results will very likely show a normal average length.
STELA testing uses an adapted qPCR technique to provide the single telomere length for a subset of chromosomes. This technique is very labor-intensive and currently used in medical, science, and biological research.
Telomere testing is a relatively new technology, and as such, it has both proponents and detractors in the field of medical genomics. New articles on the topic are being published constantly by different clinical institutions and universities, and we must think thoroughly about our options before choosing a provider.
The importance of doing your own research before committing to a provider can’t be overstated, since not all testing companies hold the same standards of quality. It’s important to work with a lab that is Clinical Laboratory Improvement Amendments (CLIA) certified to ensure that you receive accurate results.
It’s also important to remember that a single telomere analysis won’t be able to provide a full picture of your health. To achieve this, you may be recommended to take various tests over time and compare them to the baseline provided by your first result. Some providers recommend testing once a year in order to detect changes.
There are still many things we don’t fully understand about telomere length. For example, published research shows that telomere shortening isn’t always linear — it can oscillate and results taken shortly one after another may vary as a result of this phenomenon. Researchers are still unsure regarding the significance and impact of these oscillations in telomere length.
As with other types of genetic testing, it’s very likely that telomere testing will become more and more popular and accessible in the coming years. As testing technologies become more affordable and easier to reproduce, getting a telomere test could become a simple way to tell our true biological age and aging rate, and screen for many health risks.(#7-Accurate Telomere Length Test)
Additionally, having short or long telomeres isn’t the only factor in your genetic material that plays a role in your future health. Other types of genetic testing, such as whole genome sequencing (WGS) can be useful to analyze your genes and paint a full picture of your health. WGS can also estimate a patient’s risk for many conditions, from certain types of cancer to preventable diseases. WGS could even be helpful for the rest of your family members since it can detect disorders that can be passed down through a family line.
Different testing providers offer telomere testing. Some of the most well-known providers include:
As discussed above, whole genome sequencing is not only the most modern but also the most technologically advanced method for testing the length of your telomeres. Sequencing.com specializes in whole genome sequencing and is the first provider of telomere length analysis using whole genome sequencing.
Sequencing.com’s telomere test is called The Ultimate Telomere Test because it not only provides the length of your telomeres but also sequences all 30,000 genes and each chromosome end-to-end. This means that you’ll get your whole genome sequenced with the Ultimate DNA Test and can then use the test data for almost any other purpose, such as for preventive health, personalized wellness, rare disease screening, nutrigenomics, optimizing your medications, and learning about your ancestry.
It’s important to note that Sequencing.com’s telomere test does not need to be ordered by a doctor and is also one of the only telomere tests that do not require blood. Instead, all that is needed is a painless mouth swab that is easy to collect at home. There’s no need to make an appointment at a laboratory to draw your blood and no need to have the test ordered through your doctors.
The Ultimate Telomere Test is currently on sale for only $379 (35% off) and can be ordered online by anyone 18 or older located anywhere throughout the world. The DNA collection kit ships worldwide and includes two swabs that are rolled on the inside of your mouth. The swabs are then returned to the lab, which sequences your entire genome.
You’ll receive a report on your telomere length as well as a Wellness and Longevity genetic report on your risk of a wide range of preventable diseases. You’ll also own your genome data and can use it with more than 100 different DNA analysis apps and reports available at Sequencing.com.
Thanks to Sequencing.com’s Privacy First policy, your genome data is safe and secure as Sequencing.com doesn’t sell your data to anyone.Order The Ultimate Telomere Test
Life Length offers telomere tests. Their tests can be ordered by individuals or medical professionals alike, and it’s available online in the US and Canada.
This company provides tests to the individual, but they also work alongside physicians. Results include individual, median, and average telomere lengths; this analysis will also inform you of your percentage of short telomeres. This is the only commercial analysis that currently tests individual telomere lengths.
Life Length’s telomere test costs between $410 to $480, depending on whether you wish to take your own blood sample or have the company arrange a visit to a phlebotomist for you. The kit is shipped to your address, and it includes an online consultation with a specialist.
This company offers different types of tests, including a cellular Micronutrient Test to measure cellular deficiencies; the Lipoprotein Particle Profile (LPP®) for in-depth lipid analysis.
SpectraCell’s Telomere Test must be ordered by a licensed healthcare provider. The tests cost approximately $290 in addition to the fee charged by the healthcare professional. The test requires blood be collected and shipped to SpectraCell’s laboratory.
This company’s telomere analysis is called TeloYears, and it determines your average telomere length. The test must be ordered by a healthcare provider. After your physician orders the test for you, you’ll receive your TeloYears collection kit either at your physician’s office or it may be shipped to your home.
The kit allows you to collect your own blood at home by sticking your finger with a sharp pin or lancet (blade) included within the kit. You then ship your blood back to Telomere Diagnostics.
The price of the TeloYears test is unknown. In 2020 and 2021, Telomere Diagnostics’ website shows that they’ve refocused on COVID-19 testing.
This company aims to provide telomere length tests to people who suspect that they could have a case of genetically shorter telomeres. Their test determines telomere length through FISH Flow technology in different blood cell types, such as lymphocytes, T-cells, NK cells, granulocytes, and B-cells.
This analysis must be ordered by physicians and costs anywhere from $400 to $800.
No. 23andMe uses saliva samples to perform DNA genotyping. Their tests can identify different DNA mutations related to health and ancestry. This type of DNA analysis doesn’t determine telomere length.
Now that we know what science and biology have to say about the importance of telomere, we must think of another vital question: is there anything we can do to maintain a long telomere? Well, yes — and the answer could be as simple as exercise and diet.
Unhealthy habits have been found to increase a patient’s risk of telomere shortening — especially factors that increase levels of oxidative stress throughout your body and cause cell damage. These factors include:
- Lack of exercise
- Consuming an unhealthy diet
- Chronic stress
The latest research has found that having short telomeres can increase your risk of many different diseases, including:
- Coronary heart disease
- Heart failure
- Myocardial infarction (heart attacks)
- Cancer (particularly bladder, lung, gastrointestinal, renal cell, and head and neck cancers)
- Idiopathic pulmonary fibrosis
Healthy lifestyle choices, on the other hand, can aid in telomere maintenance. Long telomeres are associated with longevity, better health, and a decreased disease risk. Habits that can positively affect telomere maintenance include:
- Eating a healthy, fiber-rich diet
- Consuming foods that contain antioxidants, such as omega-3 fatty acids, vitamin E, vitamin C, and beta-carotene
- Eating smaller portions according to your dietary requirements
- Practicing exercise regularly
- Maintaining an adequate weight
- Keeping coronary heart disease risk factors (cholesterol and triglyceride levels, blood glucose, weight, insulin resistance, among others) under control.
In addition to lifestyle changes, certain medications have been shown to have the ability to achieve long telomeres. However, more research is needed on this topic — please remember to avoid self-medicating and always discuss new treatments with your physician. Medications that could help maintain a longer telomere average length include:
- Angiotensin-converting enzyme inhibitors (ACEI)
- Angiotensin receptor blockers (ARB)
- Bioidentical Hormone Replacement Therapy
- Calcium channel blockers
- Renin Inhibitors
- Serum aldosterone receptor antagonists
Learn more about genomics and the world of genetic testing by visiting our Education Center.
- What is a telomere? Your Genome. Retrieved April 5, 2021.
- What are telomeres? Australian Academy of Science. Retrieved April 4, 2021.
- Shammas M. A. (2011). Telomeres, lifestyle, cancer, and aging. Current opinion in clinical nutrition and metabolic care, 14(1), 28–34.
- Can this DNA test help predict your longevity? (2018, April). Harvard Health Publishing. Retrieved April 4, 2021.
- Montpetit, A. J., Alhareeri, A. A., Montpetit, M., Starkweather, A. R., Elmore, L. W., Filler, K., Mohanraj, L., Burton, C. W., Menzies, V. S., Lyon, D. E., & Jackson-Cook, C. K. (2014). Telomere length: a review of methods for measurement. Nursing Research, 63(4), 289–299.
- What is a qPCR? (2020, February 7). ThermoFisher Scientific. Retrieved April 5, 2021.
- Accurate Telomere Length Test Influences Treatment Decisions for Certain Diseases. (2018, February 26). Johns Hopkins Medicine. Retrieved April 5, 2021.
Dr. Brandon Colby MD is a US physician specializing in the personalized prevention of disease through the use of genomic technologies. He’s an expert in genetic testing, genetic analysis, and precision medicine. Dr. Colby is also the Founder of Sequencing.com and the author of Outsmart Your Genes.
Dr. Colby holds an MD from the Mount Sinai School of Medicine, an MBA from Stanford University’s Graduate School of Business, and a degree in Genetics with Honors from the University of Michigan. He is an Affiliate Specialist of the American College of Medical Genetics and Genomics (ACMG), an Associate of the American College of Preventive Medicine (ACPM), and a member of the National Society of Genetic Counselors (NSGC).