Hereditary diseases refer to diseases caused by changes in genetic material (such as gene mutations or chromosomal aberrations). About 4,000 genetic diseases have been discovered in humans, and more than 100 newly discovered genetic diseases are discovered every year. They are factors that seriously endanger human health and are passed down from generation to generation to varying degrees.
The secret of human inheritance that we are already familiar with lies in the genes in the cell nucleus. Genes hold the \”power\” of inheritance. They can change structurally, morphologically, and quantitatively. That is, if a lot of information from parents is passed on to the next generation through genes and carried by chromosomes. There are about 50,000 pairs of genes on the 23 pairs of human chromosomes. It is natural that several dissident molecules often appear for some reason. It can be thought that each of us may have several defective abnormal genes to varying degrees. In other words, almost all of us may be carriers of one or more genetic disease genes, and do not show abnormal symptoms. It is just because one of the parents has an abnormality in a gene at the time of conception, which is then affected by the other parent. Normality takes over, that is, is masked by normal genes.
For example, if a certain gene of the father is abnormal, but the corresponding gene of the mother is normal, most of the children born from this combination will behave normally. Although the defective genes lurk in these children, no genetic disease develops. If their parents have the same genetic defect at the same time, it can no longer be concealed and it is difficult to avoid the bad luck of genetic diseases, so the children born often behave abnormally.
In addition, children with diseases caused by the interaction of multiple genes and environmental factors, such as cleft lip, cleft palate, spina bifida, etc., have a higher probability of not suffering from the disease. There are also some genetic diseases that are determined by a defective gene in only one parent, and the disease can be manifested in offspring. This type of inheritance is a dominant genetic disease. For example, sickle cell anemia is a directly life-threatening blood disease, and the incidence rate in children is about 25%. In addition, genetic diseases may also be caused by abnormalities in the number, structure or arrangement of chromosomes that affect the fetus, and the list is endless.
Characteristics of genetic diseases
(1) Heredity :The disease-causing genes carried by patients will continue to be inherited through the reproduction of future generations, causing harm to the quality of the population that cannot be underestimated.
(2) Familial:If one person in a family suffers from hemophilia, patients with this disease will often be seen in this family. , and passed on to offspring by carrying disease-causing genes.
(3) Congenital:Genetic diseases can be manifested at birth, such as Down syndrome Symptoms, polydactyly, syndactyly, etc. However, there are also some genetic diseases that do not show symptoms when the child is born, but only appear at a certain stage of growth and development. For example, hereditary cerebellar ataxia usually does not develop until around the age of 35. No matter when the disease occurs after birth, the root cause of the disease is planted the moment after the sperm and egg fuse. Therefore, genetic diseases share innate characteristics. Children often have congenital malformations or genetic diseases before they are born, or clinical symptoms appear several years later.
(4) Life-long: Most genetic diseases are life-long, that is, they are very rare. Difficult to treat, currently only a few diseases can be treated to relieve symptoms and treat symptoms, but the causative factors cannot be eradicated, such as primary glaucoma, which is a lifelong genetic disease and brings lifelong pain to patients.
(5) High incidence rate: The offspring of patients with genetic diseases are likely to repeat the same mistakes, especially If the marriage is between close relatives, the offspring will have a high incidence of genetic diseases.
This article is provided by Baidu Reading and is excerpted from \”Three Months Before Pregnancy – Pregnancy Preparation Period\” Author: Wang Liru
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