1. What is the Recessive Allele Frequency Equation?

The recessive allele frequency equation estimates the frequency of a recessive allele in a population based on the incidence of the recessive phenotype. It assumes Hardy-Weinberg equilibrium in the population.

2. How Does the Calculator Work?

The calculator uses the equation:

Where:

• \( F \) — Frequency of the recessive allele (dimensionless)
• \( I \) — Incidence of the recessive phenotype in the population (dimensionless)

Explanation: Under Hardy-Weinberg equilibrium, the frequency of homozygous recessive individuals (q²) equals the incidence of the recessive phenotype. Therefore, the allele frequency (q) is the square root of the incidence.

3. Importance of Allele Frequency Calculation

Details: Knowing allele frequencies helps in understanding population genetics, predicting disease prevalence, and planning genetic counseling services.

4. Using the Calculator

Tips: Enter the incidence of the recessive phenotype as a decimal between 0 and 1 (e.g., 0.0001 for 1 in 10,000). The calculator will output the estimated allele frequency.

5. Frequently Asked Questions (FAQ)

Q1: What assumptions does this calculation make?
A: It assumes Hardy-Weinberg equilibrium - random mating, no selection, no mutation, no migration, and large population size.

Q2: How accurate is this estimate?
A: It's reasonably accurate for rare recessive disorders in large populations that approximate Hardy-Weinberg conditions.

Q3: What if the incidence is very low?
A: The equation remains valid, but measurement error in incidence becomes more significant for very rare disorders.

Q4: Can this be used for dominant disorders?
A: No, this specific equation only applies to recessive traits. Different equations are needed for dominant or X-linked traits.

Q5: How does consanguinity affect the calculation?
A: Consanguinity increases homozygosity above Hardy-Weinberg expectations, making this estimate less accurate in such populations.