Final answer:
Linkage disequilibrium is less likely when loci are further apart due to increased recombination events that shuffle alleles, creating more genetic diversity. Geneticists use recombination frequencies to measure genetic distances and construct genetic maps, with higher frequencies indicating less linkage disequilibrium.
Step-by-step explanation:
The further apart loci are on a chromosome, the less likely they will be in linkage disequilibrium because the probability of recombination events between them increases. Recombination can shuffle alleles between chromatids during meiosis, creating new allele combinations in the gametes. Geneticists utilize the frequency of these recombination events to construct genetic maps and measure genetic distances between genes. For example, genes with a recombination frequency of 0.5 (indicating a 50% chance of recombination) are considered to be assorting independently, which aligns with Mendel's expectations in a dihybrid cross.
When genes are closely linked, recombination is less probable, resulting in parental genotypes being passed on more frequently. However, as the physical distance between two genes on a chromosome increases, so does the likelihood of crossovers occurring between them. This occurrence decreases the level of linkage disequilibrium, essentially allowing the genes to behave as if they were on separate chromosomes and leading to more genetic variety in offspring.