Final answer:
Heterozygous advantage, also known as heterozygote advantage or overdominance, is a concept in biology where individuals who have two different alleles for a given gene on the homologous chromosome have a survival or reproductive advantage over individuals who are homozygous for either allele. Heterozygous advantage can be observed in various genetic traits, such as sickle cell anemia, where heterozygotes have a better chance of surviving against malaria. The frequency of heterozygotes in a population undergoing heterozygous advantage is likely to increase, promoting genetic diversity.
Step-by-step explanation:
Heterozygous advantage, also known as heterozygote advantage or overdominance, is a concept in biology where heterozygotes have a higher fitness compared to homozygotes. This means that individuals who have two different alleles for a given gene on the homologous chromosome have a survival or reproductive advantage over individuals who are homozygous for either allele. A classic example of heterozygous advantage is sickle cell anemia, where individuals who are heterozygous for the sickle cell gene have an advantage against malaria.
For example, let's consider a population where the frequency of the dominant allele (A) is represented as p and the frequency of the recessive allele (a) is represented as q. The frequency of heterozygotes (Aa) in the population is represented as 2pq. In a population undergoing heterozygous advantage, the value of 2pq is likely to increase due to the higher fitness of heterozygotes. This is because heterozygotes can benefit from both alleles, providing a survival advantage in certain environments or against diseases.
Overall, heterozygous advantage is an important mechanism in evolution that maintains genetic diversity in populations by promoting the survival of individuals with different alleles.