In genetics complete linkage
is defined as the state in which two loci
are so close together that alleles
of these loci are virtually never separated by crossing over
. During reproduction, chromosomes on the same chromosome pair, exchange sections of DNA. As a result, genes that were originally on the same chromosome can finish up on different chromosomes - genetic recombination
. The closer the physical location of two genes on the DNA, the less likely they are to be separated.