Discovery and Characterization of Tetranucleotide Short Tandem Repeats in North American Bears (Ursids)

Accurate individual identification is essential to wildlife crime investigations and conservation genetics. Current methodology utilizes dinucleotide short tandem repeats (STRs) that can be difficult to type accurately and have high mutation rates; however, tetranucleotide STRs have greater stability and allele diversity. The main objective of this study was to identify potential tetranucleotide STR loci and internal variants for the American black bear, brown bear, and polar bear. Barcoded genome libraries were prepared for each species from extracted and enzymatically fragmented DNA, size selected, quantified, enriched using biotinylated RNA baits to capture twelve common mammalian sequence motifs, and massively parallel sequenced. One potential locus was identified using the NextGENe® software and six potential loci were identified using algorithm mining.