Telomeres are the ends of our chromosomes that protect them, and the genetic information they contain, from damage. Studies show that telomeres can shorten over time and this shortening is linked to human aging and increased disease risk. Most telomere studies have focused on a single tissue type: blood. That has raised questions about its applicability to other tissues as researchers study the effects of aging, disease, and lifestyle factors on telomere length.
Now, a new study confirms that telomere length in whole blood can serve as a reliable stand-in for telomere length in most other tissues. That’s the conclusion after an examination of telomere length in over 20 different human tissue types from nearly 1,000 deceased human donors.
The scientists compared telomere length in blood cells to telomere length in skin, brain, lung, colon, kidney, and other tissue types. Out of the 23 tissues they studied, telomere length in most of the tissues showed a clear, positive correlation with telomere length in whole blood cells, supporting the use of easily collected whole blood cell telomere length as a proxy for telomere length in harder-to-access tissues, like brain and kidney. The finding bolsters existing research on the relationship between telomere length, ancestry, and aging.
The study was part of the Genotype-Tissue Expression (GTEx) project, a massive public resource focused on collecting samples from many different tissues from hundreds of human subjects. The study, partly funded by NHLBI, appeared in the journal Science.