What is the inheritance pattern for most blood group antigens?

What is the inheritance pattern for most blood group antigens?

• A. Dominant
• B. Recessive
• C. Codominant
• D. Corecessive

Answer: (C)

Most blood group antigens exhibit a codominant inheritance pattern. This means that when an individual has two different alleles for a blood group antigen, both alleles are expressed equally in the phenotype. For example, in the ABO blood group system, individuals with one allele coding for A and another for B will express both A and B antigens on the surface of their red blood cells, resulting in the AB blood type. This phenomenon allows for the coexistence of multiple alleles within a population, leading to the diverse blood types seen in humans. In contrast, dominant inheritance would imply that one allele would mask the effect of another, resulting in only one phenotypic expression. Recessive inheritance indicates that two copies of a recessive allele are necessary for the trait to be expressed, which is not how blood group antigens function. Corecessive, while a lesser-known term, would similarly not apply since the nature of blood group expression is better understood as codominance, allowing for the independent expression of different alleles in individuals with mixed genotypes.

Most blood group antigens exhibit a codominant inheritance pattern. This means that when an individual has two different alleles for a blood group antigen, both alleles are expressed equally in the phenotype.

For example, in the ABO blood group system, individuals with one allele coding for A and another for B will express both A and B antigens on the surface of their red blood cells, resulting in the AB blood type. This phenomenon allows for the coexistence of multiple alleles within a population, leading to the diverse blood types seen in humans.

In contrast, dominant inheritance would imply that one allele would mask the effect of another, resulting in only one phenotypic expression. Recessive inheritance indicates that two copies of a recessive allele are necessary for the trait to be expressed, which is not how blood group antigens function. Corecessive, while a lesser-known term, would similarly not apply since the nature of blood group expression is better understood as codominance, allowing for the independent expression of different alleles in individuals with mixed genotypes.