An Autosomal STR panel for population, forensic, and clinical genetics, integrated with CODIS-based analysis of the...

Short tandem repeats (STRs) are highly polymorphic markers essential for forensic science, population genetics, and clinical diagnostics. We developed a 15-locus autosomal STR panel targeting chromosomes 13, 18, and 21 for multipurpose genetic applications. Fluorescent-labelled primers were designed, and PCR products were analysed via capillary electrophoresis and sequencing. Population genetics evaluation using 127 distinct alleles from unrelated Iraqi Hawrami individuals showed that all markers remained in Hardy-Weinberg equilibrium after Bonferroni correction, and linkage disequilibrium analysis confirmed their independence. Preliminary forensic analysis indicated that all loci had a polymorphism information content (PIC) value greater than 0.5, demonstrating discriminatory capability, with D13S258 achieving the highest level of discrimination. Combined power of discrimination reached greater than 0.999999, with a match probability of 6.82 × 10^-16. The clinical assessment effectively identified trisomy 13, 18, and 21 by analysing characteristic peak height ratios and tri-allelic patterns in confirmed cases. This cost-effective STR panel suits population genetics studies, preliminary forensic evaluations, and rapid diagnostic testing, offering a versatile alternative to commercial kits. The panel's robust performance across multiple applications establishes its value for genetic research in Middle Eastern populations and as a screening assay. Complementary analysis using CODIS core loci for phylogenetic construction revealed that the Iraqi Hawrami population is most closely related to Armenian groups (Ararat and Lake Valley) and populations from southwestern Iran. These groups form a distinct Caucasus-Zagros subclade. Non-negative Matrix Factorisation of genetic structure showed clear clustering patterns, illustrating genetic transitions among Levantine, Mesopotamian, and Central Asian populations.