Post date: Jun 12, 2020 2:41:56 PM
Let's consider a chromosome. We focus on two locus on this chromosome: gene A and gene B. Gene A allele is +, gene B allele is +.
Now let's take its pair, the other chromosome that pairs with our first chromosomes. It can hold different alleles for gene A and gene b. For example alleles - and -.
Following Mendel's laws: the identity of an allele at locus A+ should not give us any information about the identity of allele B (+/-) on the same chromatid.
LD = Linkage Disequilibrium is the measure of the deviation from this expectation.