Aim: To systemically select and evaluate short tandem repeats (STRs) on the chromosome 14 and obtain new STR loci as expanded genotyping markers for forensic application.
Methods: STRs on the chromosome 14 were filtered from Tandem Repeats Database and further selected based on their positions on the chromosome, repeat patterns of the core sequences, sequence homology of the flanking regions, and suitability of flanking regions in primer design. The STR locus with the highest heterozygosity and polymorphism information content (PIC) was selected for further analysis of genetic polymorphism, forensic parameters, and the core sequence.
Results: Among 26 STR loci selected as candidates, D14S739 had the highest heterozygosity (0.8691) and PIC (0.8432), and showed no deviation from the Hardy-Weinberg equilibrium. 14 alleles were observed, ranging in size from 21 to 34 tetranucleotide units in the core region of (GATA)9-18 (GACA)7-12 GACG (GACA)2 GATA. Paternity testing showed no mutations.
Conclusion: D14S739 is a highly informative STR locus and could be a suitable genetic marker for forensic applications in the Han Chinese population.