AP Biology· difficulty 2/5
A recessive disease (aa) is lethal before reproduction. The current allele frequencies are p = 0.8, q = 0.2 in a HW population.
What fraction of newborns is expected to be affected (aa)?
0.20
0.16
0.04
0.32
Explanation
q² = 0.2² = 0.04. About 4% of newborns will be homozygous recessive (affected) under HW equilibrium.
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