How to Calculate Selection Coefficient
What is Selection Coefficient?
The selection coefficient (s) quantifies the fitness disadvantage of a genotype. If the fittest genotype has relative fitness 1, a genotype with fitness (1−s) has selection coefficient s.
Step-by-Step Guide
- 1s = 1 − w_aa/w_AA
- 2Allele frequency change: Δq ≈ −sq²p/(1−sq²)
Worked Examples
Input
w_AA=1.0 · w_aa=0.7
Result
s = 0.3 (30% fitness reduction)
Moderate selection against recessive
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