The genes controlling the first step are said to be epistatic to the genes controlling the second step. C. Epistasis vs Dominance . Epistasis is sometimes confused with dominance, as both cases refer to how the effects of one allele or gene overrides the effects of another. However they are quite different. For example, A is dominant to a. 2.
Epistasis refers to the effects of one gene overriding the effects of another gene.
If there are multiple crossovers in one meiosis, there are several possible outcomes. RF is calculated by examining the products of many meioses, not one. RF is necessary because we seldom examine the results of a single meiosis. Instead, we look at the total results from many meioses. The chart below shows the correlation between R.F., distance, crossovers per individual meiosis, and types of gametes from a total of many meioses.