Question: About how long is a DNA double helix that is made up of 900 base pairs? Suppose that genes A, B, C, and D are located on the same chromosome. The recombination frequency between genes A and B is 10%. The recombination frequency between genes B and C is 1%. The recombination frequency between genes C and D is 5%. And the recombination frequency between genes D and A is 2%. What is the relative sequence of genes A through D? A three point cross between FI AaBbCc was crossed to aabbcc. 1000 offspring was observed. Please construct a genetic map of these three loci according to the following genotypes of the offspring: