Answer:
Recombination Frequency (%) = Distance between genes (mu)
A—15—B—20---C
Expected double crossover progeny = 15% * 20% = 0.03
Coefficient of Coincidence = Observed double crossover progeny / Expected double crossover progeny
7 = Observed double crossover progeny / 0.03
Observed double crossover progeny = 0.03 * 0.7 = 0.021 or 2.1%
Number of double crosses will actually show up when a triple heterozygote is test crossed = 2.1%
genes A,B,C are linked in order. frequency of single crissover between A-B =15% and between B-C...
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