Shared allele distance (Chakraborty and Jin, 1993) [Jin, L. 93]

between individuals:

D_{{SA}_{I}} = 1 - P_{{SA}_{I}}, with P_{{SA}_{I}} = \frac{\sum_{j}^{r} S}{2r}

where the number of shared alleles S is sumed over all loci r.

between populations:

D_{{SA}_{B}} = 1 - \frac{2 {\overset{ˉ}{P}}_{{SA}_{B}}}{{\overset{ˉ}{P}}_{{SA}_{X}} + {\overset{ˉ}{P}}_{{SA}_{Y}}}

where the average proportion of shared alleles between and within populations X and Y (

{\overset{ˉ}{P}}_{{SA}_{B}}

{\overset{ˉ}{P}}_{{SA}_{X}}

{\overset{ˉ}{P}}_{{SA}_{Y}}

respectively) is computed overall possible combinations of individuals sampled.