The Power of Screening

The PowerPlex S5 System allows you to quickly screen large numbers of samples with a less expensive STR system and only type your most probative samples with a full STR system such as PowerPlex 16. With an average price of >40% less than commercially available 16-loci STR systems, a forensic laboratory can save both time and money. For specific examples refer to the case studies below:

Homicide Case

A large homicide case is submitted to the laboratory with 97 unknown samples and 3 reference samples. If all samples were typed with a standard 16-locus megaplex STR kit at a reagent cost of $17.00 per sample, the total reagent cost would be $1,700. By screening all 100 samples with PowerPlex S5 with an assumed per reaction cost of $10.00, the initial reagent cost for sample screening would be $1,000. If the lab picked 10 probative samples to complete with a megaplex kit, the additional reagent cost would be $170, for a total of $1,170 – a 31% reduction in STR reagent cost.

Labor costs can be reduced as well. Assume a mere 6 minutes per sample time savings for every sample that is screened with PowerPlex S5 prior to typing with a megaplex kit. (The time savings comes from shorter run times and less analysis time due to the need to only evaluate 5 loci instead of 16.) At 30 minutes labor per sample with a megaplex and 24 minutes per sample labor for PowerPlex S5, this is a 20% reduction in labor. With the example above, reamplifying 10% or your samples with a megaplex kit still leaves the laboratory with a 10% reduction in labor.

 

Population Screening Case

In the U.K and other regions, mass screenings or large populations have taken place to help identify potential suspects. In cases like these thousands of individuals may be screened, at significant reagent and labor costs. By using a less expensive kit to screen all the individuals and picking only those who match at all loci present in PowerPlex S5, the expenses associated with this application are dramatically reduced. If such a population includes 3000 individuals and the megaplex STR kit costs $17.00 per sample, the total reagent cost would be $51,000. If instead all 3000 samples were screened with PowerPlex S5 at a price of $10.00 per reaction, the initial reagent cost for population screening would only be $30,000. If only 1% (30) of these samples then needed to be typed with a megaplex STR kit, the additional reagent cost would only be $510 for a total of $30,510. This is a 40% reduction in STR reagent cost.

For labor, at 30 minutes labor per sample with a megaplex and 24 minutes per sample labor for PowerPlex S5, this is a 20% reduction in labor. With the example above, reamplifying 1% or your samples with a megaplex kit still results in a 19% reduction in labor.

 

Power of Discrimination

The PowerPlex S5 system includes 4 traditional STR loci: D18S51, D8S1179, TH01, and FGA. The estimated power of discrimination in the U.S. Caucasian population is approximately 1.9x10⁵.