When the population is small
or
When there is no gene flow
Small population, germ line mutation, beneficial mutation that gets into many progeny and a good deal of luck.
A mutation would have the most impact on allele frequency in a condition where it confers a significant survival or reproductive advantage, such as in situations of strong natural selection or environmental change. For example, in a population facing a new disease, a mutation that grants resistance could rapidly increase in frequency. Additionally, if the mutation leads to a drastic change in phenotype that enhances mating success, it could also quickly alter allele frequencies through sexual selection. Overall, the strength of selection pressure and the context of the environment are critical in determining the mutation's impact.
There is no gene flow.
When the population is small or When there is no gene flow Small population, germ line mutation, beneficial mutation that gets into many progeny and a good deal of luck.
When a mutation first occurs, the frequency of the new allele is very low in the population. Over time, if the allele confers a selective advantage, it may increase in frequency through natural selection.
Mutation, migration, and genetic drift
There is no gene flow - APEX
An increase in allele frequency can occur due to factors such as genetic drift, gene flow from other populations, natural selection favoring that allele, or a genetic mutation that confers a selective advantage.
The frequency of an allele in a gene pool is determined by counting the number of copies of that allele in a population. This frequency can change through evolutionary processes such as genetic drift, natural selection, mutation, and gene flow. Tracking allele frequencies helps scientists study population genetics and evolutionary dynamics.
Which factor might determine whether the frequency of the new allele will increase in a population where a mutation occurs?
In a population's genetic makeup, if the frequency of the p allele decreases, it can lead to an increase in the frequency of the q allele if they are in a simple two-allele system (where p + q = 1). This is often the case in scenarios where the two alleles are in negative frequency-dependent selection, meaning that as one allele becomes less common, the other may benefit and increase in frequency. However, other factors such as selection pressures, mutation rates, and genetic drift can also influence the dynamics between p and q alleles.
An example of allele frequency is when in a population of 100 individuals, 60 individuals have the dominant allele (A) for a specific gene, while 40 individuals have the recessive allele (a). The frequency of the dominant allele (A) would be 0.6, and the frequency of the recessive allele (a) would be 0.4.
The BRCA2 mutation is associated with a variety of mutations across its gene. However, most commonly, the mutation is found in one allele of the BRCA2 gene located on chromosome 13.