Immunohaematology

Since type O blood normally lacks both A and B antigens, it will not be recognized as an alien type by the blood of anyone. As a result, anyone usually can be transfused with O blood without concern about rejection for this blood group.

You can be type A, B, AB, or O but not ABO.

The Rh blood group system is the second most clinically significant antigen system after the ABO blood group system. The Rh system is important in blood transfusion and pregnancy, as individuals who are Rh-negative can develop antibodies against Rh-positive blood. This can lead to complications during pregnancy, such as hemolytic disease of the newborn. Therefore, it is crucial to identify the Rh blood group of individuals to ensure safe blood transfusions and pregnancies.

- A person needs to be above 18 years of age with a healthy weight of more than 45 kg to be a blood donor. In certain rare cases, minors may be made to donate blood but only with parental consent. Also, it is essential to have a BP reading of above 120/80 and hemoglobin of above 12.5 Gms.

- A history of hepatitis infection disqualifies a person from being a blood donor.

In most cases these alleles are totally responsible for determining blood type phenotypes. The inheritance usually follows simple Mendelian patterns. However, there are rare exceptions such as the Bombay Phenotype described in the tutorial.

The Bombay phenotype is a rare blood type where individuals do not have the H antigen on their red blood cells. This means that they are unable to produce the A or B antigens, which are normally built on top of the H antigen. As a result, individuals with the Bombay phenotype can only receive blood from other individuals with the same phenotype, as their immune system will recognize any other blood type as foreign and potentially harmful. Therefore, the correct answer is H antigen.

In addition to suffering life threatening anemia, they also are usually jaundiced, fevered, quite swollen, and have an enlarged liver and spleen.

As a result of fetal blood entering the mother`s system during her first pregnancy with an Rh positive baby, she will regularly produce antibodies to Rh antigens. They will pass through the placental barrier into her fetus and agglutinate its blood.

In order for the fetus to be Rh positive, the father must also be Rh positive. As a result, when the mother is Rh negative and the father is Rh positive (or his Rh type is unknown), doctors usually assume that there will be a serious medical problem.

If they produced anti-A antibodies, it would destroy their own blood. However, they do normally produce anti-B antibodies since B type blood would be alien to them.

The A1 antigen refers to N-acetyl-D-galactosamine. This molecule is a component of the A antigen found on red blood cells. The A antigen is one of the blood group antigens used in the ABO blood typing system. Individuals who have the A1 antigen on their red blood cells are classified as blood type A. N-acetyl-D-galactosamine is responsible for the recognition and binding of antibodies in the immune response.

The Rh blood factor is a dominant trait. Therefore, both DD and Dd people have the Rh antigen on the surface of their red cells which makes them Rh positive.

The rules of dominance for the ABO system are that A and B are both dominant over O (i.e., O is recessive) and A and B are codominant.

Since you could inherit A or O alleles from one parent and B or O alleles from the other, you could be any of the 4 ABO types. Look at the other answers to see how this could be true.

Karl Landsteiner discovered the ABO system in 1900 and 1901 while trying to understand why blood transfusions sometimes saved lives and at other times caused death.

Based on the given information, if a mother with blood type A has a child with blood type B, it suggests that the mother is heterozygous for the trait. This means that she carries both the dominant allele (A) and the recessive allele (B) for blood type. Since the child has blood type B, it means that the mother passed on the recessive allele to the child. Therefore, the mother must be heterozygous for the trait.

If the father is homozygous dominant (DD) the chances of the fetus being Rh positive and an incompatibility problem occurring will be 100%. If the father is heterozygous (Dd), the chances are 50%. There will be no problem if the fetus is Rh negative.

Type O blood is a recessive trait, meaning it can only be expressed if both parents contribute an O allele. Type AB blood, on the other hand, is a dominant trait and requires at least one A or B allele. Since the woman has type AB blood, she must have at least one A or B allele, making it impossible for her to pass on an O allele to the child. Therefore, it is not possible for a man with type O blood and a woman with type AB blood to produce a child with type O blood.

The Rh system apparently is much more complex genetically since it involves 45 different antigens on the surface of red cells that are controlled by 2 closely linked genes on chromosome 1. In most cases, the ABO system is controlled by only 2 antigens.

O- blood group can be used to supplement a patient of any other blood group. However, sometimes O blood contains antibodies against A and B; so it is actually used as a ‘Universal Donor’ only in vary rare circumstances where blood of the same blood group is not available.