Robust STR multiplexes for challenging casework samples

Abstract

The presence of amplification inhibitors and degraded DNA in many World Trade Center (WTC) victim bone fragment samples motivated us to create STR multiplex sets displaying more robust amplification with challenging casework samples. We developed multiplex sets that co-amplify smaller versions of the larger amplicons present in commercial sets. They generate well-balanced profiles with at least five-fold the typical signal using 0.25 ng of human DNA template and generated three times the genetic information derived from commercial kits using the more challenging WTC samples. Sensitivity of the systems approaches detection of individual DNA fragment templates, requiring implementation of appropriate interpretation guidelines for this low copy number, high throughput environment.