MN and ABO blood group systems phenotype/genotype problem and solution

1. What are the main human blood group systems? In humans the main blood group systems are the ABO system, the Rh system and the MN system. 2. Why is the determination of the blood types of the donor and of the recipient important in transfusions? Red blood cells have different antigens in the outer surface of their plasma membrane; for example, the antigens A and B of the ABO system are glycoproteins of the membrane. If a donor has red blood cells with antigens not present in the red blood cells of the recipient (lacking of transfusion compatibility) the immune system of the recipient recognizes these molecules as actual antigens (i.e., foreign substances) and triggers a defense response producing specific antibodies against those antigens. The transfused red blood cells then are destroyed by these antibodies and the recipient individual may even die. 3. What are the antigens and the respective antibodies of the ABO blood group system? The ABO blood system includes the erythrocytic antigens A and B that can be attacked by the antibodies anti-A and anti-B. The antigens A and B are agglutinogens and the antibodies anti-A and anti-B are agglutinins. 4. What are the blood types of the ABO blood system? The blood types of the ABO blood system are the type A, the type B, the type AB and the type O. 5. What are the antigens and antibodies of each blood type of the ABO blood system? Type A: antigen A, antibody anti-B. Type B: antigen B, antibody anti-A. Type AB: antigens A and B, does not produce antibody A neither antibody B. Type O: does not have antigen A neither antigen B, has antibodies anti-A and anti-B. (Obviously antibodies are made by B lymphocytes not by red blood cells.) 6. What is the logic of the transfusional compatibility concerning the ABO blood group system? The transfusional compatibility for the ABO system takes into account the antigens present in the red blood cells of the donor and the antibodies that the recipient can produce. Whenever the recipient is not able to produce antibodies against antigens of the red blood cells of the donor the transfusion is compatible. So regarding ABO compatibility type A can donate to type A and to type AB. Type B can donate to type B and to type AB. Type AB can donate only to type AB. Type O can donate to all ABO types. (Any transfusion must be studied, planned and supervised by doctors.) 7. What are universal donors and universal recipients concerning the ABO blood system? Universals donors of the ABO blood type system are the individuals of the type O. Type O blood does not have antigen A neither antigen B in its red blood cells and can be donated to individuals of any ABO type. Universal recipients of the ABO blood type system are the individuals of the type AB. Type AB blood does not contain antibody anti-A neither antibody anti-B and people of this group can receive blood from any of the ABO types. 8. What is the type of genetic inheritance that determines the ABO blood group system? What are the relations of dominance among the involved alleles? The inheritance of the ABO blood system is a multiple alleles inheritance. There are three involved alleles, IA, IB and i that combine in pairs to form the genotypes. Concerning dominance, the allele i is recessive in relation to the alleles IA and IB. Between IA and IB however lack of dominance is established with the heterozygous (IAIB) manifesting distinct phenotype. 9. What are the genotypes and respective blood types of the ABO system? Since the alleles are IA, IB and i the possible genotypes are IAIA (blood type A), IAIB (blood type AB), IBIB (blood type B) and ii (blood type O). #genotypes #Cancer #aboBloodGroupSystem #MNSystem #glycoproteins #humanBloodGroupSystems #GeneticsLecture #theTypeABAndTheTypeO #transfusionalCompatibility #typeA #agglutinogens #GeneticExamQuestionsSolutions #RhSystem #antibodies #antigenA #GeneticsExamQuestionsSolutions #Iherb #theTypeB #ABOSystem #GeneticTesting #redBloodCells #erythrocyticAntigensAAndB #phenotype #antigensAAndB #Genetics101 #antigens #NikolaysGeneticsLessons #genetics