Here's how it works:
* Dominance: Usually, one allele (version of a gene) is dominant and masks the expression of the recessive allele. For example, in brown eyes, the brown allele is dominant over the blue allele.
* Codominance: In codominance, both alleles are expressed equally. This means the offspring will exhibit a combination of both traits.
Example:
A classic example is the blood type AB.
* The A allele is dominant.
* The B allele is dominant.
If a person inherits both the A and B alleles, their blood type will be AB, showing both traits equally.
Other examples:
* Roan cows: A roan coat in cows is a result of codominance between the red and white alleles.
* Sickle cell anemia: The sickle cell trait is a result of codominance between the normal hemoglobin allele and the sickle cell allele.
Key takeaway: Codominance is a special type of inheritance where both alleles contribute equally to the phenotype, resulting in a unique expression of both traits.
