Population-genetic and comparative interpopulation studies of Azerbaijan population based on the 15 autosomal STR markers.

We have investigated 765 unrelated individuals from Azerbaijan using AmpFlSTR® Identifiler® Plus PCR Amplification Kit. For each STR locus basic population-genetic and forensic parameters were determined. The calculated P-values (P) for the accuracy of the Hardy-Weinberg equilibrium (HWE) tests, showed that this parameter had a statistically significant value (P = 0.0000) only for the THO1, D18S51 and FGA loci. The values of parameters for the set of 15 STR loci such as CPE, CPD, CTPI and the PP showed that the given set of loci can be confidently used to solve identification problems for the studied population. Multiple population differentiation tests performed between Azerbaijan and other 17 world populations revealed that between Azerbaijan and Iraqi, Iranian, Turkish populations there were no significant differences on all STR loci. Additionally, comparisons of Fischer genetic distance indices (F) P-values did not reveal any statistically significant difference between Azerbaijan and Iranian populations at P < 0.05. However, with South African black population differences at all STR loci were detected. Both tests did not reveal a locus by which our population would differ from all the other compared populations. PCA and PCoA analyzes showed that the Azerbaijani population was grouped with different populations in different quarters, showing a negative and zero correlation, respectively. Regarding the location of the Azerbaijan population, there are some differences between NJ and UPGMA phylogenetic trees. For example, in the NJ tree, Azerbaijan population was grouped with Iranian, but in the UPGMA tree, it was grouped with the Turkish population. Based on Nei's genetic distance between populations the second tree has a more realistic outcome.