Investigator Argus X-12 study on the population of northern Croatia

X chromosome STR typing has emerged recently as a powerful tool, complementary to autosomal STR typing, in solving complex forensic and missing person cases. Investigator® Argus X-12 is a commercial product that allows co-amplification of 12 X chromosomal markers belonging to four linkage groups (LGs). In this study, we analyzed by capillary electrophoresis blood samples from 100 females and 102 males from a population of northern Croatia. Statistical analysis included calculation of allele and haplotype frequencies, as well as forensic parameters. The most informative marker for the northern Croatia population was DXS10135 with PIC=0.9211 and a total of 27 alleles. The least polymorphic marker was DXS8378 with 6 alleles. The proportion of observed haplotypes from the number of possible haplotypes varied from 2.74-8.57% across all LGs, with LG1 being the most informative. Of the 11 tested world populations compared to the population of northern Croatia, significant differences in genetic distance (FST) were found for Greenlandic and all non-European populations. We found that all tested markers are in HWE and can thus be used for match probability calculation. Because of high combined power of discrimination in both men and women, Investigator® Argus X-12 is applicable for the northern Croatia population in routine forensic casework.