This is an excellent study that polices up a lot of impliedconjecture that has been already well accepted. The bonus however isthat it is only in the late stage that shortened telomere length isassociated with an increased death risk.
With our developing capacity to replace tissue with stem cells thatturn the biological clock back to zero, the possibility arises thatextended life is completely plausible. In fact, right now it is acertainty.
In the meantime slowing telomere loss is good and telomererestoration is better. Efforts in those directions are available atexcessive cost, but you get the idea. This will all be commonknowledge and also common practice in about a decade.
Significantrelationship between mortality and telomere length discovered
http://www.eurekalert.org/pub_releases/2012-11/asoh-srb102012.php
A team of researchersat Kaiser Permanente and the University of California, San Francisco(UCSF) has identified a significant relationship between mortalityand the length of telomeres, the stretches of DNA that protect theends of chromosomes, according to a presentation on Nov. 8 at theAmerican Society of Human Genetics 2012 meeting in San Francisco.
While a reduction intelomere length is regarded as a biomarker of aging, scientists havenot yet determined whether it plays a direct causal role inaging-related health changes and mortality or is just a sign ofaging.
In their prospectivestudy of 100,000 multi-ethnic individuals whose average age was 63years, the researchers determined that an association betweentelomere length and mortality existed and persisted even after thedata were adjusted for such demographic and behavioral factors aseducation, smoking and alcohol consumption, said Catherine Schaefer,Ph.D., director of the Kaiser Permanente (KP) Research Program onGenes, Environment and Health (RPGEH).
Dr. Schaefer and NeilRisch, Ph.D., director of the UCSF Institute for Human Genetics, areprincipal investigators of the Genetic Epidemiology Research Study onAdult Health and Aging (GERA). UCSF professor and Nobel laureateElizabeth Blackburn, Ph.D., led the research on telomere lengthmeasurement.
The telomere research,part of the GERA project, has genotyped over 675,000 markers of100,000 KP Northern California patients and linked them with healthdata from their electronic medical records. To obtain DNA forgenotyping and telomere measurement, the researchers collected salivasamples from the patients, who volunteered for the project andprovided scientists with access to their electronic medical records.
Two years prior tothe saliva collection, the researchers conducted a detailed survey ofthe patients' demographic and behavioral factors, providing a uniqueopportunity to address questions of telomere epidemiology and aging.
"With these data,we examined demographic relationships with telomere length,behavioral influences and relationship of telomere length with allcauses of mortality following sample collection," said Dr.Schaefer. "Although we found that shorter-than-average telomereswere prospectively associated with mortality, only those with theshortest telomeres were at increased risk of death."
Dr. Risch added,"While this could indicate a direct effect of telomere length onhealth, it will also be important to examine the extent ofpre-existing diseases in these individuals to understand theirpossible role in the biological connection between telomere lengthand longevity."
Dr. Risch said that heand the other scientists expected to and did find that telomerelength was inversely correlated with age, and women had longertelomeres than men except as young adults. All analyses controlledfor age and gender.
Harvard Medical Schoolscientist Cynthia C. Morton, Ph.D., who was not involved in thestudy, commented, "The GERA study is especially impressive forthe large resource of DNA samples and corresponding electronicmedical records available from KP patients, and for the outstandinggroup of scientists collaborating in the research."The intriguingfindings on telomere length in the GERA cohort are no doubt amongmany yet forthcoming, prompting further investigations into the basisfor ethnic differences in telomere length such as whether specificoral environmental exposures in ethnic groups might account fordifferences in telomere lengths in saliva DNA samples," addedDr. Morton, William Lambert Richardson Professor in Harvard'sdepartment of obstetrics, gynecology and reproductive biology.
Like several otherinvestigations, GERA detected significantly longer telomeres amongAfrican Americans than other groups, but did not reveal a significantdifference between European-Americans, Latinos and Asians.
According to the GERAresults, telomere length was positively correlated with such factorsas level of education and body mass index (BMI), and negativelycorrelated with cigarette smoking and alcohol consumption. However,telomere length was not associated with major depression orstress-related disorders, although other studies have reported anassociation between telomere length and depression and stressfulevents.
Links between shortertelomeres and risks for cardiovascular disease, diabetes, somecancers, depression, pulmonary fibrosis, vascular dementia,osteoarthritis and osteoporosis have been detected by Dr. Blackburn,one of three scientists honored with the 2009 Nobel Prize inPhysiology or Medicine, and her research group as well as other labs.Telomeres are special DNA sequences attached to the ends of each ofthe 46 chromosomes in human cells. When telomeres become too short,cells can no longer multiply.
The researchers'presentation is titled "The Kaiser Permanente/UCSF GeneticEpidemiology Research Study on Adult Health and Aging: Demographicand Behavioral Influences on Telomeres and Relationship withAll-cause Mortality."
About ASHG
The American Societyof Human Genetics is the primary professional membership organizationfor nearly 8,000 human genetics specialists worldwide. The ASHGAnnual Meeting is the world's largest gathering of human geneticsprofessionals and a forum for renowned experts in the field.
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