A stick-sized DNA chip that tells you your body’s ‘true age’: Donga Science

Recently, Brian Johnson, an American billionaire in his 40s who invests 2.7 billion won every year in rejuvenation, saying, “I will return to the body of a teenager,” became famous on social networking services (SNS). Johnson became a hot topic by revealing that although his real age is 45, the biological age of his heart is 37 and his skin age is 28.

As Johnson’s story spread, people’s interest in ‘biological age’, rather than age on resident registration (chronological age), grew. Biological age, or biological age, is calculated by measuring the level of aging of each part of the body. If you manage your biological age well, you can live younger than your original age.

Kim Young-jin, a researcher at the Genomic Research and Technology Development Department of the Future Medical Research Department of the National Institute of Health, introduced the method of measuring biological age and the actual impact of biological age on our body at the ‘Science Journalists Association Science Media Academy’ held at the Gwanghwamun HJ Center in Seoul on the 23rd. .

Biological age has a direct impact on health. Researcher Kim said, “As a result of a survey of 1,895 Koreans, the incidence of colorectal cancer increased by 12% for each year that biological age increased, and it was also associated with the occurrence of various chronic diseases such as high blood pressure.”

The easiest way to measure biological age, which is a measure of health evaluation, is to measure ‘methylation’. Methylation is a phenomenon in which a methyl group (H3c), in which one hydrogen atom is removed from methane, is attached to a cytokine base. Cytokines are relatively small immune proteins contained in the blood. It is a protein immunomodulator secreted from immune cells and is involved in transmitting various biological signals within the body.

This methylation has a significant impact on changes in the human body. This is because actual gene expression is regulated according to methylation. It can also cause proteins to be produced or not produced. Even identical twins can have significant differences in appearance and disease development depending on the level of methylation.

Methylation is also related to aging. Researcher Kim said, “When people are young or maintain desirable lifestyle habits, genes are expressed well, but when surrounding conditions change, gene expression is not performed well, which can lead to diseases or senescence.” Senescence is a condition in which physical functions deteriorate as aging continues, making people highly vulnerable to minor stress or physical changes, making them prone to diseases.

The simplest way to measure methylation is using DNA. Researcher Kim said, “A small stick-sized chip is sufficient.” The method for measuring methylation-based biological age is as follows. First, specially treated DNA is placed into a small chip. DNA is extracted from blood and then chemically treated to make it ready for investigation. Next, the degree of methylation for each chromosome is measured through optical scanning. Biological age is estimated by analyzing the measured methylation information using statistical analysis. This is a method of expressing the accelerated rate of methylation in a graph and comparing it with the rate of change in chronological age.

Methylation changes are used in a variety of ways other than measuring biological age. According to Researcher Kim, by checking the rate of methylation change, drinking and smoking habits can be predicted with an accuracy of 74.3% and 86.5%, respectively. This is also used in scientific investigations. Suspects can be identified based on traces of smoking and drinking left behind in methylation.

Researcher Kim said, “Recently, the importance of living healthily while delaying aging is emerging rather than simply living longer,” adding, “Biological age is an indicator of my health status and can be easily measured, so it will be used by many people in the future.” “It will get attention,” he said.