Human Blood Type Inheritance
The blood grouping systems commonly used include the ABO system that was first described by Karl Landsteiner. The discovery of blood grouping systems helped to avoid unnecessary death emanating from blood transfusion. The basics of blood grouping systems lie behind the inheritance of genes. The possession and inheritance of blood groups attribute to the parents who combine alleles responsible for the blood groups. The parents thus play a pivotal role in determining the blood groups of the offspring. This paper will work towards the discussion of inheritance of human blood groups.
An Overview of Blood Groups
Blood grouping involves the use of ABO ...view middle of the document...
These people can only receive blood from people who possess blood group O. Those who have blood group AB do not have antibodies and thus called universal recipients because they can receive blood from all other blood types. They cannot donate blood to other blood groups because they can cause negative reactions. A person thus cannot receive blood from a person expressing the same antigens as antibodies as it can lead to agglutination or bust of red blood cells and consequently to death.
Blood Type Inheritance
Both parents contribute towards the blood groups of their resulting offspring. The inheritance of blood types is controlled by the ABO genes that occur as a single gene possessing three types of alleles. These genes are hosted by the ninth chromosome, 9q34. Environmental changes do not affect the organization of the genetic makeup controlling the genes. The alleles that control the blood group inheritance include A, B, and O. The alleles A and B exist as dominant genes over the allele O: the Allele O thus remains a recessive allele (Daniels, 2008). A person with AO or AA genotype will have A phenotype while those with BB or BO genotype have a B phenotype. People of blood group O have OO phenotypes as they inherit O alleles from both parents. In blood group AB, both alleles A and B are inherited from both parents and thus exists as co-dominant alleles.
Table Showing Parental Combination of Alleles and the Resulting Offspring Genotypes
PARENT ALLELES A B O
A AA AB AO
B AB BB BO
O AO BO OO
Sometimes the ABO blood groups may not act upon the normality of inheritance. The scenario can occur due to the existence of the third...