1. What is Allele Frequency?

Allele frequency is the relative frequency of an allele (variant of a gene) at a particular locus in a population, expressed as a fraction or percentage. It is a fundamental concept in population genetics.

2. How Does the Calculator Work?

The calculator uses the basic allele frequency equation:

Where:

• \( p \) — Allele frequency (dimensionless, range 0-1)
• Numerator — Count of the specific allele in the population
• Denominator — Total count of all alleles at that locus

Explanation: For a diploid population of N individuals, there are 2N alleles at each autosomal locus.

3. Importance of Allele Frequency

Details: Allele frequencies are essential for understanding genetic variation, Hardy-Weinberg equilibrium, evolutionary processes, and disease risk in populations.

4. Using the Calculator

Tips: Enter the count of your allele of interest and the total number of alleles (2N for diploid populations). Both values must be positive integers with allele count ≤ total alleles.

5. Frequently Asked Questions (FAQ)

Q1: What's the difference between allele and genotype frequency?
A: Allele frequency refers to single alleles, while genotype frequency refers to combinations of alleles (e.g., AA, Aa, aa).

Q2: How do you calculate allele frequency from genotype data?
A: For a diploid population: p = (2 × count of AA + count of Aa) / (2 × total individuals).

Q3: What is considered a rare allele?
A: Typically, alleles with frequency <1% are considered rare, though definitions vary.

Q4: Can allele frequency be greater than 1?
A: No, allele frequencies range from 0 (absent) to 1 (fixed in the population).

Q5: Why track allele frequencies over time?
A: Changes can indicate evolutionary processes like selection, drift, migration, or mutation.