Principle of Independent Assortment and LinkageMendelâ€™s second theory, the principle of independent assortment, came from his observations of dihybrid crosses. As you can see in the example above, the distribution of alleles for one trait in the gametes does not influence the distribution of alleles for the second trait. In other words, during meiosis, the alleles segregate, or assort, independently of each other. The traits will be distributed equally in the gametes.
This principle is violated when two genes are physically linked, or joined, on the same chromosome. When this occurs, the alleles for two different traits do not assort independently, but instead are inherited together.