The performance enhancements made to the Identifiler® Plus Kit greatly facilitate the analysis of casework mixtures, which often contain PCR inhibitors, and where the minor component may be present at a very low level. The enhanced sensitivity, greater capability to overcome inhibition and improved heterozygote and intracolor balance afforded by the Identifiler® Plus Kit allows the analyst to analyze and interpret mixtures more easily and reliably than was previously possible (Figure 4).
Figure 4. An example of a casework sample that yielded no profile when analyzed with the Identifiler® Kit but yielded a high quality, interpretable mixture profile with the Identifiler® Plus Kit. 1ng input DNA and 28 cycles of amplification were used for both kits.
Electropherograms Showing Detection of the Minor Contributor in Mixtures Inhibited with 300µM Hematin
Figure 5. An illustration of the ability of the Identifiler® Plus Kit to detect alleles from the minor contributor, even in mixtures containing significant levels of PCR inhibitors. Alleles for the minor contributor are highlighted above in profiles from mixture samples inhibited with 300µM of hematin. In the 3:1 and 10:1 mixture samples, the Identifiler® Plus Kit maintains excellent profile balance and detects minor component alleles at all loci, while the nearest competitor kit shows inhibition in the high molecular weight region with declining peak height and fails to detect the minor contributor for two loci in this region.