It can often be seen in the crowd that both parents are tall in a family, but the children are not tall; Some parents are short, but their children are not short, and some will be tall.
If one of the parents is short, the offspring may be uneven, both tall and short. It is generally known that a child's height is related to his parents' inheritance, but the above situation is not absolute, because height is controlled by many factors, such as environmental factors, nutritional status, living habits, work nature and other factors will affect the development of height.
In the past, Japanese people were generally shorter than our country, but in recent years, the average height of Japanese people has greatly exceeded that of their parents, which also proves the relationship between heredity and environment in eugenics.
Of course, the influence of environment on heredity is not autumn. In human inheritance, some genetic characteristics are very stable, and blood types and fingerprints cannot be changed. For example, in patients with schizophrenia and asthma, environmental factors account for only 20%, genetic effects account for 80%, and some genetic diseases account for a small proportion.
Modern medical technology provides people with the opportunity to make full use of external environmental factors to remedy genetic defects and prevent environmental factors from causing physical and mental defects in the next generation by understanding the knowledge of genetics and eugenics and consulting specialized hospitals.
In order to give birth to healthy and intelligent children, we must prevent the birth of children with genetic diseases through various channels. Consanguineous marriage, family members or people with genetic diseases, congenital mental retardation, birth history of deformed children, abnormal development of sexual organs with unexplained stillbirth and pregnancy, and elderly women over 35 years old should seek genetic counseling from geneticists before giving birth.
Determine whether there is a genetic disease, the cause of the genetic disease and the mode of inheritance. According to the results of family analysis and genetic examination, the risk rate of recurrence of genetic diseases in children is estimated, and scientific prevention and control countermeasures are put forward. Try to reduce and avoid the occurrence of genetic diseases and reduce the burden on society and families.