In recent years, people often hear the words “DNA” and “genes”, such as DNA for paternity testing, crime solving, and genetically modified animals and plants. DNA is short for deoxyribonucleic acid, which is found in every cell of the body and is the chemical carrier of human genetic information. Genes are specific nucleotide sequences on DNA molecules with genetic effects that guide the synthesis of important substances in the body, such as proteins, and maintain normal physiological functions of the body.
If a gene is abnormal, or even a very small fragment of a gene is abnormal, it can cause abnormal development, disease, or even death. It can pass genetic information to the next generation through replication, thus causing the offspring to exhibit similar traits to those of their parents. There are approximately 20-25,000 genes in humans, and about 1,000 and 70 genes are currently available for medical testing.
I. Understanding genes
A gene is a functional fragment of a DNA molecule, the basic unit of genetic information and the most fundamental factor that determines all biological species; genes determine the life and death of people, and are the cause of health, beauty and longevity, and are the manipulators and regulators of life. Therefore, where there is life, there are genes, and all forms of existence and death of life are determined by genes, including your looks, height, weight, skin color, personality, etc. are inseparable from genes.
A gene (Gene, Mendelian factor) is a DNA or RNA sequence that carries genetic information (i.e. a gene is a fragment of DNA or RNA with genetic effects), also known as a genetic factor, and is the basic genetic unit that controls traits. Genes express the genetic information they carry by directing the synthesis of proteins, thereby controlling the performance of traits in individual organisms.
What is the relationship between genes and health (disease)?
Modern medical research has proven that almost all diseases, except trauma, are related to genes. Just like blood is divided into different blood types, normal genes in the human body are also divided into different genotypes, i.e. genetic polymorphism. Different genotypes have different sensitivity to environmental factors, and sensitive genotypes can cause diseases under the action of environmental factors. In addition, abnormal genes can directly cause diseases, and the diseases that occur in this case are genetic diseases.
It can be said that there are three underlying causes that trigger diseases.
1. Acquired mutations of genes ;
2. Interaction between normal genes and the environment;
3. inherited genetic defects.
In the vast majority of diseases, the cause can be found in the genes.
Genes, through their guidance of protein synthesis, determine the efficiency with which we absorb food, eliminate toxins from the body and respond to infections.
The first group of genetically related diseases has more than four thousand species, acquired through genes inherited from either the father or the mother.
The second group of diseases are common, such as heart disease, diabetes, and many types of cancer, and are the result of the interaction of multiple genes and multiple environmental factors.
Genes are the chemical carriers of human genetic information that determine what is similar and what is not similar to our predecessors. When genes are “working” properly, our bodies can develop and function normally. If a gene is abnormal, or even a very small fragment of a gene is abnormal, it can cause abnormal development, disease, and even death.
A healthy body relies on the constant renewal of the body to ensure proper protein quantity and quality, and these proteins work in conjunction with each other to ensure the proper execution of various body functions. Each protein is the product of a corresponding gene.
Genes can change, some changes do not cause changes in the quantity or quality of proteins, others do. Such changes in genes are called mutations. Changes in the quantity or quality of proteins can cause abnormal body functions that result in disease.
III. What is genetic testing?
Genetic testing is a technique that is performed by extracting DNA from the nucleus of cells in the blood and other body fluids.
Genetic testing can be used to diagnose diseases and to predict disease risk. Disease diagnosis is the use of genetic testing technology to detect mutated genes that cause inherited diseases. The most widely used genetic tests are for the detection of hereditary diseases in newborns, the diagnosis of genetic diseases and the auxiliary diagnosis of certain common diseases. More than 1,000 genetic disorders can be diagnosed by genetic testing techniques.
Of great excitement in recent years is the development of predictive genetic testing. Genetic testing is used to detect the risk of disease before it occurs and to prevent or intervene early. Currently, genetic testing can be used to predict more than 20 diseases.
The test begins by extracting the subject’s genes from blood or other cells. Then this part of the gene is copied many times using primers that can identify genes that may have mutations and PCR technology, and the presence of mutations or the presence of sensitive genotypes in this part of the gene is determined using mutation gene probe methods with special markers, enzyme digestion methods, gene sequence detection methods, etc.
IV. What is the difference between genetic testing and traditional testing (physical examination)
Our usual medical tests are designed to detect specific symptoms of disease or existing lesions. The development of modern science has facilitated the continuous development of medical tests that can go into the subtleties of the disease for vertical or horizontal profiling.
As we all know, the basic component of the human body is the cell, and if we can start a kind of substantive analysis of the cell, we can find the root cause of the disease. For example, cancer is the result of mutation and mass replication of cells in the human body. General medical tests are designed to see if cancer cells are already present in your body, but there is no way to know about the cells that have not produced cancer but are already at risk. Genetic testing, on the other hand, can tell you exactly whether there is a possibility or chance of a certain disease occurring in a certain period of your life, giving you an early warning notice so that you can take early and effective measures to prevent it.