Inversion and crossover recombination contributions to the spacing between two functionally linked genes.

The roles of inversion and crossover recombination in determining the spacing between two functionally linked genes on an individual strand of DNA and the resulting genetic organization throughout the population is not well understood. We employ a computer simulation to look at the spacing between functionally linked genes after many generations of a population of haploid individuals, each with a single chromosome. Simulations show that inversion and crossover recombination combine to create four attractors in gene spacing. The two major attractors include one in which the linked genes are forced to be near each other and one in which the linked genes are forced to be separated by one third of the chromosome length. Multiplicative functional linkage between two linked genes also causes a decreased average spacing compared to additive and random functional linkage.