Parents are type A and type B blood respectively, can you give birth to a child with type O?

Parents are type A and type B blood, which may give birth to type O children! It depends on the situation of parents and families. The highest probability is 25%! Look at the information for your reference, I hope it will help you!

Genetic law of blood group

Blood type is determined by three genetic factors: A, B and O, and most of them can be judged according to parents' blood type.

Possible blood types of babies. The genetic law of blood type is: A+A → A, O; A+B→A、B、O、AB； A+O

→A、O； A+AB→A、B、AB； B+B→B、O； B+O→B、O； B+AB→B、A、AB； O+O→O； O+AB

→A、B； AB+AB→AB, AB. Therefore, according to the above blood type inheritance law, if the blood type of both husband and wife is "A"

Type A and B, the baby's blood type will be "O" or "ab" in addition to "A" or "B".

In addition:

The fourth quarter blood type and blood transfusion principle

2004-4- 13 16:50:00

View [Fonts in Large Fonts and Small Fonts]

(Keywords: blood type; Erythrocyte agglutination; Erythrocyte blood type; ABO blood group system; Rh blood group system; White blood cells; Platelet blood type; Human leukocyte antigen; HLA blood transfusion principle)

The fourth quarter blood type and blood transfusion principle

First, blood type and erythrocyte agglutination

If the blood drops of two people with incompatible blood types are mixed on a glass slide, the red blood cells in it will aggregate into a group. This compatibility is called agglutination. Agglutination of red blood cells is sometimes accompanied by hemolysis. The same thing happens in blood vessels when blood with incompatible blood types is input into circulating blood. Aggregated red blood cells can block capillaries, hemolysis can damage renal tubules, and it is often accompanied by allergic reactions, which can be life-threatening.

The mechanism of erythrocyte agglutination is antigen-antibody reaction. The specificity of lectin depends entirely on some specific glycoproteins embedded in erythrocyte membrane. Glycoprotein plays the role of antigen in agglutination reaction, so it is called agglutinin. The specific antibody that can react with lectin on erythrocyte membrane is called lectin. Lectin consists of γ -globulin dissolved in plasma. When antigen-antibody reaction occurs, because the binding site of each antibody to antigen is about 10, the antibody forms a bridge between several red blood cells with corresponding antigens, thus clustering them.

In human blood, there is a specific group of lectins on red blood cells. At present, many different antigens have been identified on red blood cells, and about 30 antigens can trigger quite violent physical reactions. Blood type refers to the type of specific antigen on red blood cells. Table 3-5 lists nine most important blood group systems, including abo, rh, mnss and P, and their specific antibodies. About 400 antigens with different characteristics can be identified on the erythrocyte membrane by modern immunological means. There are 300 million different possible combinations based on the classified antigen types. It can be seen that the most important blood groups of blood group antigen are abo system and rh system.

Table 3-5 Important Blood Groups and Their Specific Antibodies

blood-group system

antibody

Hemolytic transfusion reaction

Abo anti-a has

Anti b you

There is little resistance to a 1.

Anti-h no

Right anti -c has

Anti-c you

Anti-chemical weapons

Anti-d you

Anti-e ni

Anti-e ni

Mnss has little resistance to m, n, s and S.

P anti p 1 none

Lutheranism is anti-lub.

Kyle anti-K has

Lewis is anti-lea, while B is.

Tamiflu has anti-fya

Kidd turned against jka.

Although blood type usually refers to the blood type of red blood cells, blood group antigens existing on red blood cells also exist on white blood cells, platelets and general tissue cells, and white blood cells and platelets also have their own unique antigens.

Second, the red blood cell blood type

190 1 year, landsteiner discovered the first blood group system, namely abo blood group system, which has since revealed the mystery of blood group for human beings and made blood transfusion a safer clinical treatment method.

abo blood group system

1.abo blood group classification and its material basis ABO blood group divides blood into four types according to the existence of lectin A and lectin B on erythrocyte membrane. When red blood cells only contain lectin A, they are called type A; If there is type B lectin, it is called type B; If both type A and type B lectins are called ab type; If these two lectins do not exist, they are called type O. People with different blood types contain different lectins, that is, there is no lectin that can prevent their own red blood cell agglutination. The serum of type A people only contains anti-B agglutinin. The serum of type B people only contains anti-A agglutinin. There are no anti-A and anti-B lectins in ab human serum. The serum of type O people contains anti-A and anti-B lectins (Table 3-6). Later, it was further found that all four blood types of red blood cells contain H antigen, and O-type red blood cells also contain H antigen. H antigen is the structural basis for the formation of A and B antigens, but the antigenicity of substance H is very weak, so there is generally no anti-H antibody in serum. Through careful detection of antiserum, it can be found that type A can be further divided into subtypes a 1 and a2. The antigens A and a 1 are contained in erythrocytes of subtype a 1, while the antigen A is only contained in erythrocytes of type a2. Accordingly, a 1 serum only contains anti-B agglutinin, while a2 blood contains anti-a 1 agglutinin besides anti-B agglutinin. Therefore, when a 1 type blood is transfused to a2-type people, the anti-a 1 lectin in serum may combine with a 1 antigen on a 1 type human red blood cells to produce agglutination reaction. According to the survey, in China Han people, the number of type a2 and a2b is less than that of type A and ab 1% respectively. Even so, we should pay attention to the existence of subtype A when determining blood type and blood transfusion.

Table 3-6 Lectins and Lectins in ABO Blood Group System

blood type

agglutinogen

agglutinin

Type a

a

Anti b

Type b

b

Anti-a

Ab type

a+b

not have

O type

not have

Anti-a+ anti-b

The specificity of various blood group antigens in abo system depends on the sugar chain contained in glycoprotein. These sugar chains are oligosaccharide chains composed of several sugar groups. These oligosaccharide chains are exposed on the surface of red blood cells. Figure 3-9 shows the structural differences of oligosaccharide chains of H, A and B antigens in abo system.

Fig. 3-9 chemical structure of abh antigen substance

2. Genetic characteristics of blood type Blood type is hereditary. Different genes that appear in the same position on chromosomes are called alleles. The genes that control the production of A, B and H antigens in aboa(h) system are alleles. Only two of the above three isoenzymes may appear in diploid chromosomes, one from the father and the other from the mother. These two alleles determine the blood group genotype of offspring. These two genotypes first determine the amino acid composition and sequence of transglucosidase, that is, the type of transglucosidase produced, and then determine the composition of oligosaccharide chain showing the specificity of blood group antigen, that is, human blood group phenotype. Table 3-7 shows the possible genotypes that determine each blood group phenotype in abo system. As can be seen from the table, gene A and gene B are dominant genes, and gene O is recessive. Therefore, phenotype O on red blood cells may only come from two O genes, while phenotype A or B may come from ao and bo genotypes respectively, so it is entirely possible for parents of type A or B to give birth to children of type O. Knowing the genetic law of blood type, we can infer the parent-child relationship from the phenotype of blood type of children. For example, an ab-type person can never be the father of an O-type child ... But it must be noted that in forensic medicine, when it is necessary to judge the parent-child relationship according to the blood type phenotype, it can only be used as a negative reference, not as a positive judgment. Because there are many blood types on blood cells, the more blood types are determined, the higher the reliability of making negative judgments.

Table 3-7 Structure of ABO (H) Blood Group System

Phenotype

genotype

Erythrocyte antigen

Natural antibodies in serum

a

a 1a 1

a+a 1

Anti b

a 10

Aortic second sound

a2a2

a+h

Anti-B, 10% people have anti-a 1.

a2o

b

bb

b

Anti-a

pah

abdominal muscle

abdominal muscle

a+a 1+b

-

a2b

a2b

a+b+h

25% people are resistant to a 1

o

OO

h

Anti-a anti-b

There is no antibody of abo system in newborn blood; In the first year after birth, this antibody gradually appears in the plasma, which can fight against antigens that are not found on your own blood cells. Most of these natural antibodies belong to igm, and the reasons for their formation have not been fully clarified. It is speculated that substances or certain food ingredients released by intestinal bacteria can stimulate the production of blood group antibodies. Because some intestines have the same antigenic determinants as red blood cells.

The distribution of blood group antigens in different regions and ethnic groups is different. Take a lot of abo systems as an example. Among the people in Central Europe, more than 40% are type A, slightly less than 40% are type O, about 10% are type B, and about 6% are type ab. Among the native Americans, 90% belong to O type. The distribution of abo blood group in China is also different. See Table 3-8 for details. Understanding the blood type distribution law of various regions and ethnic groups is helpful for anthropology to study the origin and relationship of ethnic groups.

Object of investigation

Number of people under investigation

(1)

a

b

abdominal muscle

o

Number of people (1)

%

Number of people (1)

%

Number of people (1)

%

Number of people (1)

%

Han (ha)

40,980

12,83 1

3 1.3 1

1 1,50 1

28.06

4002

9.77

12,646

30.86

Uygur

1,5 13

44 1

29.22

483

3 1.92

172

1 1.36

4 16

27.50

Zhuang people

1,487

3 16

2 1.25

4 10

25.57

58

3.90

703

47.28

the Huis

1,355

369

27.23

384

28.34

1 15

8.48

487

35.94

kazakh

885

202

22.82

264

29.83

83

9.38

336

37.97

Xibe or Xibe

344

86

25.00

138

40. 12

36

10.46

84

24.42

UZbek (Uz)

129

33

25.58

50

38.76

13

10.08

33

25.58

Kyrgyz

124

23

18.54

Forty nine

39.52

nine

7.26

43

34.68

Tatar (TT)

37

15

40.54

13

35. 14

1

2.70

eight

2 1.62

Yi ethnic group

1007

288

28.60

303

30.09

82

8. 14

334

33. 17

Bai (ba)

500

170

34.00

1 17

23.40

Fifty-six

1 1.20

157

3 1.40

put on

507

1 12

22.8

150

29.59

40

7.89

205

40.44

Jingpo

20 1

70

34.83

4 1

20.39

14

6.97

76

37.8 1

Department of Veterans Affairs

520

200

38.46

1 12

2 1.54

73

14.04

135

25.96

Tujia nationality

960

362

37.7 1

2 19

22.8 1

6 1

7. 19

3 10

32.29

Shanghai Institute of Biological Products Blood Group::> Page 9. Shanghai People's Publishing House 1 Edition 1977 Investigation Report of Physiology Teaching and Research Section of Hunan Medical College

3.ABO blood group test correctly judging blood group is the basis of ensuring blood transfusion safety. Generally speaking, blood transfusion can only be considered if the abo system has the same blood type. The method of determining abo system is: drop one drop of anti-B, one drop of anti-A and one drop of anti-a- B serum on the glass slide respectively, add one drop of red blood cell suspension to each drop of serum, gently shake to make red blood cells and serum mix evenly, and observe whether there is agglutination (Figure 3- 10).

Figure ABO blood group determination 10

(2) rh blood group system

1.Rh blood group system and its distribution in the population In the process of searching for new blood group substances, when rhesus monkey red blood cells are repeatedly injected into rabbits, rabbits will have an immune response, and at this time, antibodies (lectins) against rhesus monkey red blood cells will be produced in rabbit serum. When the serum containing this antibody is mixed with human red blood cells, it is found that about 85% of white red blood cells can be agglutinated by this serum, which shows that these red blood cells have the same antigen as rhesus monkeys, so they are called rh positive blood groups. Another 15% of people's red blood cells are not agglutinated by this serum, which is called r h negative blood group, and this blood group system is called rh blood group. Among all ethnic groups in China, about 99% of Han nationality and most other ethnic groups are rh positive, and only about 1% are rh negative. However, among other ethnic minorities, there are more rh-negative people, such as Miao 12.3% and Tatar 15.8%.

2. Genotype and expression of Rh blood group system Using serum test, it is proposed that Rh blood group system on human red blood cells includes five different antigens, which are called C, C, D, E and E respectively. Theoretically, three pairs of alleles cc, dd and ee control six antigens. However, in fact, no single anti-D serum was found, so it is considered that D is a "static gene" and D antigen is not expressed on the surface of red blood cells. Among the five antigens, antigen D has the strongest antigenicity. Therefore, red blood cells containing D antigen are usually called rh positive; The lack of D antigen on red blood cells is called rh negative.

3.3. The characteristics of RH blood group and its significance in medical practice It has been pointed out that the lectin of abo system, that is, natural antibody, has been in human serum since several months after birth. However, there is no natural anti-rh antibody in human serum. Only when rh-negative people receive rh-positive blood can they produce anti-rh antibodies through humoral immunity. In this way, there is generally no obvious reaction after the first blood transfusion, but antigen-antibody reaction can occur when rh positive blood is transfused for the second time or many times, and the input rh positive red blood cells agglutinate.

Another difference between rh system and abo system is the characteristics of antibodies. The antibody of abo system is generally a complete antibody igm. The antibody of rh system is mainly incomplete antibody igg, which is easier to penetrate the placenta. Therefore, when a negative mother is pregnant with a positive fetus, the red blood cells or D antigen of the positive fetus can enter the mother's body, and immune antibodies, mainly anti-D antibodies, are produced in the mother's blood through immune reaction. This antibody can enter the blood of the fetus through the placenta, which makes the fetal red blood cells agglutinate and dissolve, leading to hemolytic anemia of the newborn and even death of the fetus in severe cases. However, a large number of fetal red blood cells generally only enter the mother during childbirth, and the antibody concentration in the mother's blood rises slowly, which usually takes several months. Therefore, the first pregnancy often does not have a serious reaction. If the rh-negative mother has a rh-positive fetus, the high concentration of rh antibody in the maternal blood will penetrate the placenta and destroy a large number of fetal red blood cells.

Three, white blood cells and platelet blood types

White blood cells and platelets are related to red blood cell antigens such as A, B, H, mn, P, etc. In addition, it has its unique antigen, which has clinical significance, especially histocompatibility antigen, which is of great significance for selecting suitable donors for organ tissue transplantation and blood component infusion. The antigens of white blood cells and platelets can make the recipient have an immune response. At this time, blood transfusion can cause fever reaction, accelerate the destruction of transplanted organs and tissues, and shorten the survival time in the body.

Human leukocyte antigen (hla) is the strongest homologous antigen on human leukocyte. Hla system is composed of a large number of antigens, which is an extremely complex antigen system. The genes controlling these antigens are located on the short arm of chromosome 6. There are A, B, C and d4 gene loci on this chromosome, which control seven groups of hla antigens: hla-a, hla-b, hla-c, hla-d, hla-dr, hla-dq and hla respectively. For example, there are more than 20 antigens in hla-a group, more than 50 different antigens in hla-b group and 1 1 antigen in hla-c group. According to the order of antigen discovery, the original numbers are also opposite, such as hla-a 1, A2 ... A19, etc. With the discovery of new antigens, their number continues to increase.

Hla is a glycoprotein embedded in cell membrane. According to the structure and distribution characteristics of hla, it can be divided into two categories: class I and class II antigens. Hla-a, HLA-B and HLA-C belong to Class I antigens, with a molecular weight of 56,000, and consist of heavy peptide chains and light peptide chains. Their antigen specificity is determined by the amino acid sequence on the heavy peptide chain. These antigens are collectively referred to as Class I antigens; They are not only distributed on white blood cells and platelets, but also widely distributed on nucleated cell membranes of various normal tissues and organs and tumor tissues. Other hla antigens, namely D, dr, dp and dq, belong to Class II antigens with molecular weight of 63,000, and they are only distributed on B cells, macrophages, monocytes and endothelial cells.

Hla system is not only closely related to organ transplantation, skin transplantation, bone marrow transplantation and sedan chair transportation in medicine, but also can be applied to paternity test and anthropological research. When used for paternity testing, there are many combinations of hla-A and hla-b, and there are few opportunities for the same phenotype. For example, 15 hla-a and 20 hla-b can produce 20246 phenotypes. Therefore, in the negative judgment of parent-child relationship, the reliability of hla judgment can reach more than 90%. The frequency of hla has obvious racial differences. For example, in Caucasian race, hla-a-a30 and b42 antigens appear less frequently than other races, while in North American Indian race, hla-b5 1 antigens appear more frequently. Therefore, hla system is an important indicator of anthropological research.

Platelets also have some unique antigens, such as pi, zw and ko systems, which have nothing to do with the same antigens on red blood cells or white blood cells. These antigens can produce immune antibodies due to blood transfusion and pregnancy. About 50% patients can have anti-platelet transfusion antibodies in their serum after long-term repeated platelet transfusion. They can cause fever reaction, shorten the survival time of input cells, and cover up the existence of red blood cell-specific antibodies, thus affecting the correctness of blood group determination. When anti-platelet antibodies appear in pregnant women's serum, it will lead to neonatal thrombocytopenia.

Fourth, the principle of blood transfusion

Blood transfusion has become an important means to treat some diseases, save the lives of the wounded and ensure the smooth operation of some operations. However, it is not uncommon for patients to suffer serious injury or even death due to blood transfusion mistakes. According to American statistics, 1976 to 1985, 10 year. There were 159 cases of blood transfusion death in the United States, of which 137 cases were due to abo system error, accounting for 86%. In order to ensure the safety and improve the effect of blood transfusion, we must pay attention to the principle of blood transfusion.

With the development of medicine and science and technology, blood transfusion therapy has developed from simple whole blood transfusion to transfusion of whole blood or blood components. Component transfusion is to prepare various effective components in human blood, such as red blood cells, granulocytes, platelets, plasma, etc., into high-purity or high-concentration products and then input them. This can not only improve the curative effect, reduce adverse reactions, but also save blood sources.

When preparing for blood transfusion, it is necessary to ensure that the abo blood types of donors and recipients are consistent, because incompatible blood transfusion of this system often causes serious reactions. For women of childbearing age and patients who need repeated blood transfusions, it is also necessary to match the rh blood groups of blood donors and recipients to prevent the recipients from producing anti-rh antibodies after sensitization.

Even if blood transfusion is carried out between people with the same abo system blood type, cross matching test must be carried out before blood transfusion, that is, not only the donor's paper cells, but also the recipient's serum should be detected for serum matching (this is called the main side test); Moreover, the matching test of recipient cells and donor serum should be done (this is called secondary side test). This can not only check whether the blood group determination is wrong, but also find out whether there are some other agglutinates or lectins in the red blood cells or serum, which is enough to cause red blood cell agglutination. The parallel fork blood matching test should be carried out at 37℃ to ensure that the possible agglutination reaction can be fully displayed.

If there is no agglutination reaction on both sides of the cross-matching test, it is a matching match and blood transfusion can be carried out; If there is agglutination reaction on the main side, it is incompatible with blood and cannot be transfused; If there is no agglutination reaction on one side and there is agglutination reaction on the secondary side, blood transfusion can only be carried out in an emergency, not too fast and too much, and close observation should be made. In case of transfusion reaction, stop transfusion immediately.

In the past, people with type O blood were called "universal blood donors", thinking that their blood could be given to people with other blood types. But at present, it is considered that this kind of blood transfusion is not enough, because although O-type red blood cells are not agglutinated by the plasma of the recipient, anti-A and anti-B agglutinin in O-type human plasma can agglutinate with red blood cells of other blood groups. When the input blood volume is large and the lectin in the donor plasma is not fully diluted by the recipient plasma, the recipient's red blood cells will be widely agglutinated.

In short, blood transfusion is a multi-link process, and mistakes in each link may cause serious accidents. Therefore, large-scale blood transfusion surgery will