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Example · Hardy–Weinberg calculator
Cystic fibrosis affects about 1 in 2,500 newborns. How common are carriers?
- The recessive phenotype frequency is q² = 1/2500
- q = √0.0004 = 0.02, so p = 1 − q = 0.98
- Carriers: 2pq = 0.0392, about 1 in 25.5
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