Explain the phenomena of co dominance with example
Answers
ABO blood group in human being is an example of multiple allelism. There alleles for the gene I i.e. IA,IB,i. When IA and IB are present together the blood group is AB. Both A and B. are expressed and is called codominance.
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ABO blood grapes in human population is an example of multiple allelism and codominance. There are three alleles of gene l, i.e., IA,IB and i. thus exhibiting multiple alIelism. Out of these three alleles any two alleles may occur in human being, one alleles is contributed from each parent. The alleles IA + IB are dominant over allele i and produce A and B phenotypes respectively. But however when alleles IA and IB are present together both of them express equally and independently producing AB phenotype. This is a phenomenon called codominance.
Definition of Codominance
We look and act the way we do because of our genes. Genes are units of hereditary information that are located on segments of chromosomes. The genes for a specific trait may exist in different forms known as alleles.
An example of an allele or a gene is a flower color. A flower may have alleles that make it red, or pink, and so on. Alleles that always show up when they are present are known as dominant alleles. Alleles that are masked or hidden by dominant alleles are known as recessive alleles. In some situations, both alleles are expressed equally. A genetic scenario where neither allele is dominant or recessive and both get expressed is known as codominance.
Examples of Codominance
If a person has the type A protein, they have type A blood. If a person has the type B protein, they have type B blood. If a person has type O blood, then neither protein is present. If a person is type AB, then they have both A and B proteins present in their blood. If a person is type A or type B, this means that they have the dominant A or dominant B allele present in their blood. All other alleles are masked. If a person is type O, it means that neither the type A or type B allele is dominant. However, if a person is type AB, this means that both the A allele and the B allele are equally expressed and are therefore codominant.
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