The ABO system in humans is controlled by three alleles, usually referred to as IA, IB, and IO (the “I” stands for isohaemagglutinin). IA and IB are codominant and produce type A and type B antigens, respectively, which migrate to the surface of red blood cells, while IO is the recessive allele and produces no antigen.
What is controlled by multiple alleles?
The majority of human genes are thought to have more than two normal versions or alleles. Traits controlled by a single gene with more than two alleles are called multiple allele traits. An example is ABO blood type.
Multiple Allele Traits.
|Genotype||Phenotype (blood type)|
What are 3 combinations of alleles?
Human blood type is determined by codominant alleles. There are three different alleles, known as IA, IB, and i.
Which trait is controlled by multiple alleles in humans?
The best characterized example of multiple alleles in humans is the ABO blood groups, discussed in the Non-Mendelian Inheritance concept. Other human traits determined by multiple alleles would be hair color, hair texture, eye color, built, physical structures, etc.
What are examples of multiple alleles?
Two human examples of multiple-allele genes are the gene of the ABO blood group system, and the human-leukocyte-associated antigen (HLA) genes. The ABO system in humans is controlled by three alleles, usually referred to as IA, IB, and IO (the “I” stands for isohaemagglutinin).
How do multiple alleles work?
Multiple alleles is a type of non-Mendelian inheritance pattern that involves more than just the typical two alleles that usually code for a certain characteristic in a species. … Sometimes, one of the alleles is completely recessive to the others and will be masked by any of those that are dominant to it.
Is skin color an example of multiple alleles?
Polygenic Inheritance: Human skin color is a good example of polygenic (multiple gene) inheritance. Assume that three “dominant” capital letter genes (A, B and C) control dark pigmentation because more melanin is produced.