allele frequency
Quick Summary
In genetics, allele frequency refers to the ratio of a specific allele's occurrences within a population compared to the total number of alleles at that genetic locus. This measurement is a fundamental tool in population genetics, used to describe the genetic makeup of populations and understand evolutionary changes.1234
Allele frequencies can change over time due to various factors, including mutation, natural selection, and genetic drift. Mutation is the ultimate source of new genetic variation, but it typically changes allele frequencies very slowly. Natural selection favors certain alleles over others based on environmental conditions, leading to shifts in frequency. Genetic drift, particularly in smaller populations, can cause random fluctuations in allele frequencies. The study of these changes is central to understanding evolution.2354
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- heredityPopulation genetics
In population genetics, allele frequency is the measurement of the commonness of an allele. The convention is to let the frequency of a dominant allele be p and that of a recessive allele q. Both are generally expressed as decimal fractions. In the above example, p changes from…
Read MoreIn population genetics, allele frequency is the measurement of the commonness of an allele. The convention is to let the frequency of a dominant allele be p and that of a recessive allele q. Both are generally expressed as decimal fractions. In the above example, p changes from…
Read More - heredityHardy-Weinberg equilibrium
…as selection, that can change allele frequencies. Despite these stringent requirements, many natural populations that have been studied are in Hardy-Weinberg equilibrium for the genes under investigation. The Hardy-Weinberg equilibrium constitutes an important benchmark for population genetic analysis.
Read More…as selection, that can change allele frequencies. Despite these stringent requirements, many natural populations that have been studied are in Hardy-Weinberg equilibrium for the genes under investigation. The Hardy-Weinberg equilibrium constitutes an important benchmark for population genetic analysis.
Read More