Genes are found on chromosomes, which are double-stranded, twisted molecules of DNA. Chromosomes are found inside the nucleus or center of a cell. At the end of each chromosome, one can find stretches of DNA called telomeres. Telomeres make it possible for cells to divide, protect genetic data, and hold the secrets to how humans get cancer and age.
Much like the plastic tips on the ends of shoelaces keep them from fraying, so too do telomeres keep the ends of chromosomes from fraying or sticking to each other. If this were to occur, an organism’s genetic information would be scrambled leading to disease, cancer, and even death. Each time a cell divides, the telomeres get shorter.
A cell becomes senescent, or inactive, and ceases to reproduce or dies when the telomere gets too short. The process of reaching this limit, known as the Hayflick limit, is associated with cancer, aging, and death of the organism. It is because of this that telomeres have received the comparison to a bomb fuse.
Telomeres in Depth
Telomeres are chains of chemical code known as DNA. Genes and chromosomes as a whole are also made up of DNA sequences. Telomeres, as well as other DNA, are made up of four nucleic acid bases:
- A for adenine
- C for cytosine
- G for guanine
- T for thymine
Telomere’s DNA consists of one strand of repeating sequences of TTAGGG attached to another strand of repeating sequences of AATCCC. In scientific terms, a telomere would be described as a repeat of six base pairs. As humans age, their telomeres shorten. A newborn has telomeres that are about 8,000 base pairs long, while an elderly person’s telomeres may be as short as 1,500 base pairs. As a frame of reference, the entire chromosome consists of about 150 million base pairs.
With each cell division, the average person loses between 30 and 200 base pairs from the telomere length. Because of this, cells can usually only divide about 50 to 70 times before they die, become senescent, or mutate into cancer cells. Interestingly, telomeres maintain their length in heart muscles, since these cells do not divide.
What Purpose Do Telomeres Server?
The part of chromosomes containing the life-essential genes would get shorter with each cell division if telomeres did not exist. So, basically, telomeres allow cells to divide without losing genes. To create new blood, bone, skin, and other cells, cell division is needed. Cells would become cancerous, die, or malfunction without telomeres to protect the chromosome ends from fusing together and degrading the cell’s genes.
Telomeres also play a role in the aging process. A team of scientists at the University of Utah, led by Geneticist Richard Cawthon, found that shorter telomeres are correlated with shorter lives. People over the age of 60 were eight times more likely to die from infectious diseases and three times more likely to die from heart disease.
In the lab, scientists have been able to use telomerase, a naturally-occurring enzyme used to rebuild telomeres, to lengthen telomeres. This has allowed human cells to keep dividing well past their normal limit. These results taken in conjunction with Cawthon et. al.’s study suggests that a human’s lifespan could be increased through the use of telomerase to build telomeres.
Telomeres and Immortality
All humans experience telomere shortening. Yet, there is promising research and products on the market suggesting this shortening can be reversed. Cawthon says stopping the process of telomere shortening can add up to 30 years to the human lifespan. In his study, though, he found that telomere shortening could only account for a fraction of the factors leading to an increased chance of dying. There are a number of other research that suggests the other factors for living longer are easily in your control.
While telomere length does indeed play a clear role in lifespan, factors such as oxidative stress, gender, and glycation play important roles in the aging process. Oxidative stress is caused by and repaired by many of the same substances that can affect telomerase production. Glycation occurs when glucose sugar binds to proteins, lipids, and DNA and stops them from doing their job.
Telomere length is important for protecting chromosomes. Once telomeres get too short, then there is the threat of cancer, death, and diseases. Although it is not the only factor affecting one’s length of life, telomeres are an important one. Lengthening telomeres through the activation of telomerase can likely increase lifespans by up to 30 years.
If interested in telomerase activating products, there are many on the market. As of this writing, there is only one that has been proven to increase lifespans in humans with clinical human trials. It is called Dr. Dave’s Best TA 65. It uses a proprietary blend of astragalus root extract and other herbs to activate telomerase and increase telomere length. Always check with a qualified health professional before taking a new supplement.