In 2009, three scientists, Elizabeth Blackburn, Carol Greider, and Jack Szostak, won the Nobel Prize in Physiology or Medicine for their discovery of how telomeres and telomerase protect chromosomes. Since then, the research on telomeres and aging has been unstoppable.

The shortening of telomeres is considered a biological marker of cell aging. Most of our genetic material is hidden in the chromosomes of cells. Chromosomes are like a long skipping rope. At both ends of the skipping rope, there is a protective device called telomere to ensure that the DNA and genetic information in the cell can exist intact and stably. When the chromosomes replicate, a small segment of terminal DNA is lost every time they replicate. Telomeres are the protective caps of our chromosomes. Every time a cell divides, the telomeres will lose a little bit. When they can no longer shorten, the cells will die because they cannot divide. After the telomeres are worn, the chromosome protective caps gradually disappear, the number of cell divisions decreases, and the number of cells in important organs gradually decreases. Therefore, telomeres are called "life clocks" by scientists.

Telomeres can prevent cells from entering indefinite division. Not all cells can divide indefinitely, and telomeres can be easily extended after being shortened by cell division. This is common in eggs, sperm, and most stem cells. Regular cells cannot replace lost information. So in normal cells, telomeres become shorter and shorter with subsequent cell divisions. Once telomeres are severely insufficient, cells will stop dividing and enter a state of cellular senescence, ready to be cleared by the immune system. If cancer cells can achieve a limited division, then controlling cancer will surely achieve a cross-century success.

Damage in the coding region is difficult to detect, and telomeres can protect the coding region of the chromosome. Normally, DNA is composed of two complementary sequences that can bond to each other. DNA damage can also spontaneously change one base pair to another. Without the protection of the protective cap, the coding region may bond with other molecules, resulting in serious consequences. If two chromosomes or one chromosome bonds with other molecules, it will be a disaster. The use of protective caps at the ends of chromosomes can solve this problem well and prevent the coding region from binding to other locations. The bonding method of the protective cap to DNA is the same as the DNA base pairing method.