What is the Law of Independent Assortment?

Different genes get sorted into gametes independently of one another and the allele a gamete receives for one gene does not influence the allele received for another gene. The biological selection of an allele for one trait has nothing to do with the selection of an allele for any other trait.

The physical basis for the law of Independent Assortment lies in meiosis I of gamete formation, when homologous pairs line up in random orientations at the middle of the cell as they prepare to separate. So the gametes inherit different combinations of paternal and maternal homologoues (and thus, the alleles on those homologoues) because the orientation of each pair is random.

Independent assortment occurs in eukaryotic organisms during meiotic prophase I and produces a gamete with a mixture of the organism's chromosomes. Along with crossing over, Independent Assortment increases genetic combinations. Thus a zygote normally ends up with 23 chromosome pairs, but the origin of any particular chromosome will be randomly selected from paternal or maternal chromosomes. This contributes to the genetic variability of progeny.