A little while ago I spoke on the proliferation of opportunities to interrogate one's own genes via the offering from the equally proliferative spate of new-age companies providing kits to peer into the murky depths of our individual genomes. As fun as it may be to learn certain things about one's ancestry and genetic make-up, there are clear dangers in coming to diagnostic and prognostic conclusions based on non-physician interpretation of such data. Especially when physicians are in fact not trained to analyse such data in the first place!
While watching TV on the weekend, my attention got suddenly grabbed by an advertisement berating us all to "Redefine your age in 2017!"; the name of the provider had the extremely intriguing moniker of "TELOYEARS" which I knew just had to mean telomeres! I was kinda taken aback to be honest - while the terms DNA, and human genome, and personalized medicine have become quite commonplace in (social) media these days - is the general public now ready to be asking questions about their telomeres?!
I find it fascinating that something as specialised or even esoteric as telomere research is already out there in the public domain, with a tantalising little test on offer to inform you how well (or not) you are aging. Is the public sufficiently educated to truly understand what it is they are buying and what can of worms they may be opening, or is Teloyears just another biotech venture destined to make some serious money while simultaneously courting considerable controversy?
So what's the story? Well, briefly, telomeres are the protective nucleotide caps that keep the ends of our chromosomes intact and protected, via multiple repeats of the TTAGGG hexanucleotide sequence, with one hexanucleotide overhang at the very end. We are born with a few thousand of such repeats at the ends of our chromosomes, but this number is reduced with aging, due to the replication process not being complete at each cell division. Thus, a gradual shortening of our telomeres is part and parcel of the natural aging process, or even (as Teloyears imply) an unnaturally accelerated aging process.
It's an enticing little story, even if it's the usual soft focus lens take on things, with glamorous, healthy, active people young and old simply bursting with vitality, no doubt due to very sexy telomere counts! And that's all very well, in fact it is likely to be those active, fit, middle-aged folks who will be the major clients of such companies. In other words, I am fit and healthy, and the test confirmed my telomere length to be like ten years younger than me!
That will feel good, no doubt. But what about those that felt they were doing great, and the test informs them they are actually older than their years? If their lifestyle is already top notch, what are they to do next to stop the onslaught of telomere shortening? So much of it is probably in the genes already, that if it's low, then it's low! Are people who have let themselves go, and can see it in the mirror and/or on the scale, likely to pay for a test that confirms their worst fears or what they already know? Will such a test be the single factor that will cause them to overhaul their lifestyle?
Again, what are physicians supposed to do when their patients come to them with the results of their Teloyears test? Maybe I am misinformed, but it's my opinion that if you stroll in all newly educated and tested to your doctor's office, exclaiming woe due to criminally short telomere repeat numbers, the doc is likely to say "Telo-whaaaaat?!" I just don't think the medical profession is ready to truly interpret and prognosticate based on such data, and at best one is likely to be told to eat less, exercise more, stress less and sleep more. Business as usual, in other words.
Telomeres have been and are the focus of intense research, and not just in terms of cellular aging. Clearly, one advantage of shorter telomeres would be that it is not compatible with the cell division/growth seen in cancer, and in fact, maintenance of telomere length is a hallmark of cancer cells. Like almost everything in life, too much of a good thing is often a bad thing. So, overly short telomeres is a sign of cellular aging and contributor to cellular senescence, and overly long telomeres is a sign of cellular "youth" and contributor to cancer.
There are several key players in regulation of this process, including TERT (telomerase reverse transcriptase), the shelterin complex (including TRF1 and TRF2), and the newly discovered TZAP (telomeric zing finger-associated protein) which was the subject of a groundbreaking paper published in SCIENCE just this past week. In this case, rather than the currently fashionable issue of shortened telomeres, the authors studied the question of how longer telomeres would actually be a cancer risk, and how do healthy cells avoid the problem.
It turns out that not only do our telomeres shorten with age, but we do have a mechanism in place to prevent them from becoming overly longas well, and that is driven by TZAP. So, when telomere length becomes too long, the concentration of the shelterin complex goes down, permitting association of TZAP with telomeres, resulting in a trimming of telomere ends. Clearly, telomere shortening can also be considered a good thing, too!
Almost certainly, telomere shortening is a factor associated with age-dependent diseases but the cause-and-effect relationship is far from clear, if it exists at all. Is it the shortened telomeres that caused the disease, or is it that the shortened telomeres are just another marker of aging process that inandof itself led to the disease? It's the chicken and egg question, again. Much more research is needed, of course, and one has to be careful about the claims being pushed at us by various companies making money off of our genes.
The world of personal health and fitness is unquestionably a brave new world, with various wearables poised to revolutionise healthcare as we know it. Now you can have a device on your wrist that can measure your activity, your resting heart rate, your sleep patterns, stairs climbed, and some even offer blood pressure monitoring. So we are more and more likely to be monitoring such parameters, and sharing that information with our doctors. But I feel we are still some way off from discussing the results of 23andme's inherited genetic risk factor data or our telomere length issues with them!
That will feel good, no doubt. But what about those that felt they were doing great, and the test informs them they are actually older than their years? If their lifestyle is already top notch, what are they to do next to stop the onslaught of telomere shortening? So much of it is probably in the genes already, that if it's low, then it's low! Are people who have let themselves go, and can see it in the mirror and/or on the scale, likely to pay for a test that confirms their worst fears or what they already know? Will such a test be the single factor that will cause them to overhaul their lifestyle?
Again, what are physicians supposed to do when their patients come to them with the results of their Teloyears test? Maybe I am misinformed, but it's my opinion that if you stroll in all newly educated and tested to your doctor's office, exclaiming woe due to criminally short telomere repeat numbers, the doc is likely to say "Telo-whaaaaat?!" I just don't think the medical profession is ready to truly interpret and prognosticate based on such data, and at best one is likely to be told to eat less, exercise more, stress less and sleep more. Business as usual, in other words.
Telomeres have been and are the focus of intense research, and not just in terms of cellular aging. Clearly, one advantage of shorter telomeres would be that it is not compatible with the cell division/growth seen in cancer, and in fact, maintenance of telomere length is a hallmark of cancer cells. Like almost everything in life, too much of a good thing is often a bad thing. So, overly short telomeres is a sign of cellular aging and contributor to cellular senescence, and overly long telomeres is a sign of cellular "youth" and contributor to cancer.
There are several key players in regulation of this process, including TERT (telomerase reverse transcriptase), the shelterin complex (including TRF1 and TRF2), and the newly discovered TZAP (telomeric zing finger-associated protein) which was the subject of a groundbreaking paper published in SCIENCE just this past week. In this case, rather than the currently fashionable issue of shortened telomeres, the authors studied the question of how longer telomeres would actually be a cancer risk, and how do healthy cells avoid the problem.
It turns out that not only do our telomeres shorten with age, but we do have a mechanism in place to prevent them from becoming overly longas well, and that is driven by TZAP. So, when telomere length becomes too long, the concentration of the shelterin complex goes down, permitting association of TZAP with telomeres, resulting in a trimming of telomere ends. Clearly, telomere shortening can also be considered a good thing, too!
Almost certainly, telomere shortening is a factor associated with age-dependent diseases but the cause-and-effect relationship is far from clear, if it exists at all. Is it the shortened telomeres that caused the disease, or is it that the shortened telomeres are just another marker of aging process that inandof itself led to the disease? It's the chicken and egg question, again. Much more research is needed, of course, and one has to be careful about the claims being pushed at us by various companies making money off of our genes.
The world of personal health and fitness is unquestionably a brave new world, with various wearables poised to revolutionise healthcare as we know it. Now you can have a device on your wrist that can measure your activity, your resting heart rate, your sleep patterns, stairs climbed, and some even offer blood pressure monitoring. So we are more and more likely to be monitoring such parameters, and sharing that information with our doctors. But I feel we are still some way off from discussing the results of 23andme's inherited genetic risk factor data or our telomere length issues with them!
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