Allele Frequency Calculator

This allele frequency calculator online lets you determine the relative frequency of carrying a gene that may cause a specific genetic disease in your offspring. You can also use our Hardy Weinberg calculator online to indicate the genetic diversity of a population with respect to population genetics.

What is Allele Frequency?

In biological terms:

“The number of individual alleles of a certain type of gene that represents a variant in a population is termed allele frequency.”

In simpler terms, allele frequency (also called gene frequency) indicates how common a particular allele is within a population. Alleles are different forms of a gene found at the same location, or genetic locus, on a chromosome. You can also determine allele frequencies using an allele frequency calculator. Frequencies are usually expressed as a percentage, and our online tool allows you to calculate them in just a few minutes.

Genotype Frequency:

“The percentage of individuals in a population that carry a specific genotype is termed genotype frequency.”

Genotype frequencies show the distribution of specific genetic variations in a population. If you are wondering how to calculate genotype frequency, you can use our online genotype frequency calculator to get accurate results quickly.

Phenotype Frequency:

“The proportion of individuals in a population that exhibit a particular observable trait or phenotype is known as phenotype frequency.”

If you want to calculate phenotype frequency quickly, you can use our Phenotype Frequency Calculator, which provides results in seconds.

Gene Frequency:

“The ratio of a specific allele to the total number of alleles at its genetic locus in a population is termed gene frequency.”

You can use our Gene Frequency Calculator to estimate the proportion of alleles and study genetic diversity within a population.

How to Calculate Allele Frequency?

Allele frequency can be calculated using the Hardy-Weinberg equation, which relates genotype and phenotype frequencies within a population. This equation provides a simple way to estimate allele frequencies and study the genetic structure of populations. In other words, the Hardy-Weinberg equilibrium formula is directly connected to calculating allele frequencies.

The Hardy-Weinberg equation is given as:

p² + 2pq + q² = 1 Where:

p² represents the frequency of individuals with two healthy alleles, also called homozygous dominant (AA).
2pq represents the frequency of individuals with one healthy and one mutant allele, known as carriers or heterozygous (Aa).
q² represents the frequency of individuals with two mutant alleles, also called homozygous recessive (aa).
1 represents the total population for the specific gene.

Solved Example:

A person has a specific disease, and his wife is a carrier of the same disease. He wants to know the probability that he is also a carrier, given the following: homozygotes = 55, heterozygotes = 54, and rare homozygotes = 5. How do we find the allele frequency?

Solution:

Healthy Allele Frequency (p) = 0.7193 (71.93%)

Mutant Allele Frequency (q) = 0.2807 (28.07%)

Frequency of two healthy alleles (p²) = 0.5174

Frequency of one healthy and one mutant allele (2pq) = 0.4038

Frequency of two mutant alleles (q²) = 0.0788

If you want to calculate allele frequencies quickly using the Hardy-Weinberg equation, you can perform the calculation manually with the values above.

How Does the Allele Frequency Calculator Work?

Our online Hardy-Weinberg calculator allows you to quickly calculate carrier frequencies and allele distributions within just a few clicks. Here’s how it works:

Input:

First, select whether you want a simple or advanced calculation.
Enter the required parameter values into the designated input fields.
Click the “Calculate” button to perform the computation.

Output:

The calculator provides the following results:

Frequency of healthy and mutant alleles (in percentage)
Number of individuals with one or two healthy alleles
Number of individuals with one or two mutant alleles

FAQ’s:

How do you calculate allele frequency?

An allele frequency can be calculated by dividing the number of times a specific allele is observed in a population by the total number of copies of all alleles at that particular genetic locus. The easiest way to calculate this is by using an online allele frequency calculator.

How do you calculate allele frequency and genotype frequency?

Allele frequencies have to add up to 1 (p + q = 1). Once the allele frequencies are known, the expected genotype frequencies can be calculated using the Hardy-Weinberg principle. For example:

Genotype	Expected Frequency
aa or A2A2	q × q = q²

You can also use a genotype frequency calculator to determine genotype frequencies easily.

How is phenotype frequency calculated?

Phenotype frequency is calculated by dividing the number of individuals displaying a particular phenotype by the total number of individuals in the population.

What is Homozygous and Heterozygous?

A person is homozygous at a gene locus if both alleles are the same, and heterozygous if the two alleles are different.

Is allele and gene the same?

No, an allele is a variant form of a gene. Each gene exists at a specific locus on a chromosome, and an individual inherits one copy from each parent. The two copies may or may not be identical.

How many alleles are in a gene?

A gene can have multiple different alleles in a population, but an individual carries only two alleles for each gene—one from each parent.

Who has stronger genes, mother or father?

In general, dominant genes determine trait expression regardless of which parent they come from. There is no universal rule that genes from the father are stronger than those from the mother; it depends on dominance and the specific gene.

Are alleles dominant or recessive?

Alleles can be either dominant or recessive. A dominant allele expresses its trait over a recessive allele when both are present in a heterozygous individual.

Is an allele a trait?

No. An allele is a specific form of a gene, whereas a trait is a physical or biochemical characteristic determined by one or more alleles.

Conclusion:

Allele frequencies are essential for understanding genetic diversity within a population. Changes in allele frequency over time indicate processes such as genetic drift or the introduction of new mutations. You can easily calculate the allele frequency of a gene using our online allele frequency calculator in just a few steps.

References:

From Wikipedia: Allele Frequency – Calculation of allele frequencies from genotype frequencies.

From Khan Academy: Allele frequency & the gene pool; Darwin meets Mendel—Microevolution and population genetics; Example: Finding allele frequency.

From Study.com: Allelic Frequency – Definition & Explanation, What Is Allelic Frequency?, Allelic Frequency and Diploids.