May 11, 2020

Lifespan Given by Parents


Now the super-aged society is imminent, and many news reports about health and longevity come out: the secrets of longevity of the people who are listed in Guinness World Records for living more than 120 years; longevity villages and the lifestyle of the villagers around the world; and a dog that lived 26 years in Japan until it died recently.

Why does living a longer life than others draw people’s attention? It is because of mankind’s common desire of longevity. This proves that life is a mystery that even science has not solved yet, despite the remarkably developed civilization.

Life is something that people can easily feel, but it is very hard to define. Life is a common quality that a living creature has when alive, and it is generally defined as various characters such as metabolism1, regeneration, and growth. However, it is difficult to say that the definition is perfectly scientific yet, because life is a combination of various scientific fields such as physiology, physics, biochemistry, and molecular biology, and vital phenomena cannot be seen only in one aspect. That is why the dictionaries include a subsidiary explanation, “the period between birth and death.” The most distinctive nature of life is that it is limited, having the beginning and the end.

1) Metabolism is all the chemical processes that occur within a living organism in order to maintain life such as digestion, breathing, and photosynthesis.

Then, how is a limit to life determined? It is known that each animal species has its own lifespan—the limited time of life. The mayfly, an insect known to have the shortest lifespan, lives from a few hours up to a few days after it becomes imago. The hamster lives for about two years, the dog for about twelve to sixteen years, the cow for about twenty years, the elephant for about sixty to seventy years, and the turtle for over two hundred years. Although they live in similar environments and ecology conditions, there are dramatic differences in their lifespans, depending on their species. It is due to the difference in genes that decide lifespan. Through heredity, the parents’ features and characteristics are passed on to their descendants, as the saying that goes, “An onion will not produce a rose.”

It is natural and common that a child resembles his parents. But it hasn’t been long since it was known to the world that the secret lies in DNA in cells. Genes, which dominate the parents’ biological characteristics2, are transmitted to the next generation through reproductive cells (sperm or ovum). Since animals too receive genes from their parents, it is impossible for a cat to give birth to a dog or for a cow to give birth to a foal. A child receives from his parents various genes that determine not only height, skin tone, hair shape, but also personality and disease. Lifespan, too, is related to the genes inherited by the parents, so that dogs cannot live as long as humans live on average, no matter how long they live.

2) Characteristics are observable features, or traits of an organism, whether acquired or inherited from the parents, such as the eye color and academic skills.

Through the Human Genome Project3, a scientific research project to learn human DNA in detail, scientists began to think that a person’s lifespan too is drawn on the map of each person’s genes. Up until decades ago, it was generally believed that a human’s lifespan is decided 80% by lifestyle and 20% by genes. However, from the end of the 1990s, the surge of research results that suggest the existence of the genes responsible for longevity began to emphasize genetic factors.

3) Human Genome Project: Genome is a compound word of gene and chromosome, meaning the overall genetic information. Human Genome Project is a mega international science program that forms human genetic map by discovering three billion bases of human DNA and checking the genes in DNA. This project started in 1990 and ended in 2003, but many parts of the genetic map still remain blank. When all the blanks of the genetic map are filled in, it will be a great help to discover the causes of diseases and prevent or treat genetic diseases.

A recent research went much further and showed that genetic factors have a bigger influence on long lifespan than environmental factors. According to the report of a research team at Albert Einstein College of Medicine published in the journal of Gerontological Society of America in August, 2011, three common genes for longevity were discovered in the genes of 500 Jews whose average age was 100 years old. What is interesting is that one third of them had habits irrelevant to good health. This means that the decisive factors on lifespan are genes.

All parents want to pass on to their children the genes of a good height, intelligence, health, and longevity if they can, but they cannot help but give only the genes they have. Some people are born to a healthy family with the genes of a long life and live long over 100 years. Some people live a tough life as they receive from their parents genetic diseases such as color blindness or hemophilia. That is why many scientists are making an effort to cure diseases by studying genes. Not only that, but they are also conducting an active research on slowing down aging and prolonging life.

However, it seems that hundreds of genes come into aging, so it is not easy at all to discover the mechanisms of aging. It is also a challenging task because the speed of aging is all different between organs or tissues, and even within a tissue. It is impossible to fix all the 100 trillion cells of the body through genetic modification.

According to Leonard Hayflick, the founder of the research on aging of cells, cells do not grow in number infinitely, but they have certain limits of life. In his experiment on human cell culture, an embryonic cell stopped after dividing a hundred times, whereas an old person’s cell divided just twenty times. There is a “lifespan clock” that measures our time in cells, and death is unavoidable. Afterwards, a telomere, which is known to get shorter whenever cells are divided, was discovered by cell biologists. This lifespan clock programmed in the body cannot go backward. Living beings on this earth are born with a limited life, get old, and get to face death in the end.

Telomere, which is located at the end of chromosome, protects DNA so that it may not be damaged but reproduce well. It gets shorter whenever the cell divides. When it is completely gone, cell division ends and the cell dies. For this reason, telomere is called “lifespan clock” or “aging clock.” The shiny part is telomere.

The Bible explains that God’s seed is in those who are born of God (1 Jn 3:9). In other words, God gave them His seed—His genes. Those who have received God’s genes become God’s children, and God becomes their Father and Mother. God has eternal life, not a limited life. Then, what kind of life will God’s children have? What is the way to receive God’s longevity gene—the gene of eternal life?