Originally formulated by the Austrian monk Gregor Johann Mendel, the law of independent assortment states that the distribution of alleles to gametes during meiosis is random. If one particular allele goes to one gamete, it has no influence on the likelihood of any other allele going to the same gamete.

The law of independent assortment holds true for genes on separate chromosomes, however, there are many cases where the law of independent assortment does not hold true. When the alleles are present on the same linkage group or chromosome, they are physically attached to each other and cannot show independent assortment. The further apart the alleles are the more likely that there is going to be a cross over event between them and they will be able to show independent assortment.