In real life, ordinary people often have little understanding of family affection. \”I don\’t look like my parents. Is that someone else\’s blood?\” \”I have blood type A and you have blood type B. Why is our child blood type O?\” These paradoxical questions lingered in my mind. After some thought, could it be possible that I would drag my wife and children to do a paternity test? In fact, as long as you know more about genetics, you won\’t make ridiculous jokes.
Question 1: Unlike father and mother, whose child is this child?
Positive answer: The child does not look like his parents. This does not mean that the child is not his own. The inheritance of characteristics such as appearance, height, personality, and intelligence is not only controlled by polygenes, but is also affected by non-genetic environmental factors.
There are two main types of human genetic characteristics: one is genetic characteristics completely determined by a pair of alleles, called single-gene genetic characteristics, such as blood type, DNA polymorphism, etc. Each father and mother pass on one of their genes to their offspring, forming the child\’s genotype. Once formed, it does not change. The other type is complex genetic characteristics, such as a person\’s height, fatness, skin color, IQ, personality, behavior and appearance. These genetic traits are formed by the interaction of multiple pairs of genes and environmental conditions. Each pair of genes has a small effect, and the combined effect of multiple pairs of genes determines the characteristics of an individual. During meiosis, when sperm and eggs mature, genes located on different chromosomes are randomly combined, so siblings can get different genes and look different. Furthermore, complex genetic traits are highly influenced by the environment. For example, height and weight are directly related to acquired factors such as living environment, nutritional status, and living habits; IQ is related to education.
Question 2: Can \”Black Li Kui\” give birth to \”Snow White\”?
Correct answer: Yes. The inheritance of human skin color is controlled by more than 2 pairs of genes. Genes for different skin colors have the same impact on offspring, with no obvious or recessive differences. So if the father has dark skin and the mother has fair skin, the child\’s skin tone will be \”neutralized.\” Then the offspring will be gray-black.
Question 3: If both parents are type A, can their offspring be type O?
Correct answer: Yes. Ordinary people know that there are four blood types in the human ABO blood group system: O, A, B, and AB. In fact, these 4 types are phenotypes. There are 6 genotypes: 00, AO, AA, B0, BB, AB. Therefore, if type A blood is detected at the same time, its genotype can be AA or AO, and the same is true for type B blood. Because of this, those so-called type A parents may not be AA, but AO. Then when the sperm and eggs of both parents carrying type O genetic factors are combined, the child will have type O blood. Additionally, a person\’s blood type may not remain the same throughout life. When suffering from cancer, blood transfusion, taking medicine, receiving radiation therapy, etc., the blood type will change in a short period of time and return to its original state after a period of time. And those with leukemia and aplastic anemiaAfter a bone marrow transplant, a child can permanently become the same blood type as the donor. In addition, since humans’ understanding of blood types is not yet complete, there are very few cases that “violate” the above genetic laws.
Question 4: Is it okay to have a short nose bridge when I grow up?
It\’s certainly possible, and that\’s the interesting thing about nose genetics. The inheritance of the nose continues into adulthood. Of course, if you want to have a straight, tall and narrow nose, your parents must both have small nostrils and narrow noses, and at least one nose must be straight.
Question 5: The father’s eyes are black and the mother’s eyes are blue. What color are the baby’s eyes?
The inheritance of eye color follows the principle of \”dark colors such as black are more dominantly inherited than light colors\”. That is to say, if you want your baby to have blue eyes, even if you choose a lover with blue eyes, because your eyes are black, the chance of your baby having blue eyes will be very small.
Question 6: Are myopia and hyperopia hereditary?
Whether a baby will be myopic has a certain relationship with heredity. Especially if both parents are highly myopic, the baby will be more likely to be myopic. Even if the baby is not myopic at birth, he will become a carrier of the myopia gene. Affected by the environment, it is possible to develop myopia. However, according to relevant data, the number of people who become myopic due to genetic factors only accounts for 5% of the total number of people with myopia. It can be seen that the influence of acquired environment and habits cannot be ignored. In addition, hyperopia is also related to heredity.
Question 7: Is oligobaldness hereditary?
Oligobaldness is hereditary, dominant in male babies and recessive in female babies. In short, less baldness is passed down from father to son. If the father is bald and the grandfather is also bald, the probability of having a boy is about 100%; if the father is not bald and the grandfather is not bald, the probability of having a boy is 25%; if the father is not bald and the grandfather has thick hair, then the probability of the baby being bald is The probability is almost 0.
In addition, less gray hair is also closely related to genetics. If the father has less gray hair, the baby is more likely to have less gray hair.
Question 8: If the father is short, will the baby also be short?
\”My mother is short and my father is short\” is actually a misinformation. Height is polygenic. Moreover, 35% of the factors that determine height come from the father, 35% from the mother, and the remaining 30% are related to nutrition and exercise.
Question 9: Is body size related to genetics?
Body shape is also polygenic. According to statistics, if both parents are thin, most babies will also be thin, and only 7% will be obese; if one parent is obese, 40% of babies will be obese; if both parents are obese, then 80% of babies will be obese obesity. People with obesity often have a family history, but environmental factors also have a great influence on body shape. Postnatal living conditions, nutrition, exerciseFactors such as the nature of work and the nature of work will all have an impact on body shape.
Question 10: Who does the skin color look like?
Human skin color is also polygenic, and different skin color genes have the same impact on offspring. That is, after two people with different skin colors get married, the skin color of the mixed-race child will be the intermediate skin color of the parents.
Question 11: Why do some twins look alike but are so different?
Twins can be divided into identical twins and fraternal twins. Identical twins are twins in which only one egg cell is fertilized, and after the fertilized egg divides for the first time, the two cells formed each develop into two embryos. Because the two fetuses come from the same fertilized egg and have exactly the same genetic material, their gender is exactly the same. There is almost no difference in genetic characteristics and performance characteristics, so their appearance is also very similar.
This kind of twins is also called monozygotic twins. In contrast, fraternal twins refer to twins in which two mature eggs are fertilized by two sperms to form two fertilized eggs, each of which develops into a complete embryo. Since such twins come from two different fertilized eggs, they are The genders may be the same or different, and the genetic characteristics and performance characteristics are quite different.
Question 12: Is personality inherited?
As the saying goes, \”Like father, like son\”, babies are similar and inheritable in character from their parents. But it also has something to do with acquired training. As Pavlov said: \”Character is an alloy of nature and epigenetic. Character is inherited from ancestors and is constantly changing and improving in real life.\”
Question 13: Longevity will also happen Is it hereditary?
Longevity is a polygenic inheritance, which not only involves multiple genetic genes, but is also affected by diet, exercise and environment. There are two aspects to the genetic characteristics of longevity: first, longevity can be continuous for multiple generations, alternate generations, or just two generations; second, there is maternal genetic advantage, which means that women live longer than men.
Question 14: Is there a relationship between intelligence and heredity?
Facts have shown that there is a certain relationship between intelligence and heredity. Generally speaking, if the parents have high intelligence, the baby will also have high intelligence; if the parents have average intelligence, the baby will also have average intelligence; if the parents have intellectual deficiencies, it may also lead to poor intellectual development of the baby. However, factors such as acquired education, learning, and nutrition also play a considerable role in the development of intelligence. Only by combining nature and nurture can the baby\’s intelligence be maximized.