Question

Use a numerical example to show that linkage disequilibrium between loci is expected to decay faster when the recombination rate between the loci is high than when the recombination rate is low. HINT: Assign numeric values to the coefficient of disequilibrium (D) and recombination rate (r), then determine how D changes across generations.

Answer 1

In a given example, a higher recombination rate (e.g., r = 0.30) resulted in the disequilibrium coefficient (D) decaying from 0.10 to 0.07 after one generation, whereas a lower recombination rate (e.g., r = 0.10) resulted in a slower decay of D from 0.10 to 0.09.

Step-by-step explanation:

To demonstrate how linkage disequilibrium decays over generations, let's use an example employing a numerical value for the coefficient of disequilibrium (D) and the recombination rate (r). We'll start by assuming that D is 0.10 in the first generation. If the recombination rate r is high (e.g., r = 0.30), after one generation the disequilibrium will decay according to the equation D' = D(1 - r), where D' is the new coefficient of disequilibrium. Therefore, D' = 0.10 * (1 - 0.30) = 0.07.

If the recombination rate r is low (e.g., r = 0.10), the disequilibrium will decay more slowly: D' = 0.10 * (1 - 0.10) = 0.09. This numerical example shows that a higher recombination rate results in a faster decay of linkage disequilibrium between loci compared to a lower recombination rate.

In conclusion, the recombination rate influences the speed at which disequilibrium decays: higher rates result in quicker decay of linkage disequilibrium, enhancing genetic diversity over generations.