PowerPlex^® S5 Frequently Asked Questions:

What does S5 stand for?
The PowerPlex^® S5 System is meant for forensic casework screening applications ("S") and has 5 loci.

 

Why only 5 loci?
Promega has created this STR system in response to a growing number of laboratories worldwide that use a small number of loci to screen large numbers of samples at a lower cost and faster turnaround time. The five loci included in PowerPlex S5 have a random match probability in the U.S. Caucasian population of approximately 1 in 190,000. This level of discrimination is more than sufficient to discern between the small number of donors normally encountered in a single forensic case.

 

Why would I want to screen samples?
PowerPlex S5 allows laboratories to screen the ever increasing numbers of samples being submitted to the laboratory in a time and cost efficient manner. In addition, the sensitivity of the system, which regularly obtains full profiles from as little as 50pg of DNA, allows the laboratory to get results from samples that previously would not have yielded profiles.

 

What loci are included in the system?
D18S51, D8S1179, TH01, FGA, and the sex determination marker Amelogenin.

 

What is the amplicon size range for this system?
The range of amplicon size is approximately 80 – 260bp.

 

Why did you choose these particular loci?
The loci included in the system have proven that they are amenable to a decrease in amplicon size, compatible with most national databases, and are all included in the preferred ENFSI (European Network of Forensic Science Institutes) loci.

 

What is the power of discrimination of PowerPlex S5?
The estimated power of discrimination in the U.S. Caucasian population is approximately 1.9x10^-5.

 

Is the PowerPlex S5 compatible with current PowerPlex matrix kits?
The system is compatible with the PowerPlex Matrix Standards, 3100/3130 (Cat.# DG4650) and PowerPlex Matrix Standards, 310 (Cat.# DG4640). These are the same matrix kits used for customers who are using PowerPlex 16 or PowerPlex Y.

 

Do I need to buy Taq DNA polymerase?
No, the PowerPlex S5 system includes Taq DNA polymerase in the master mix that is inside the kit. No purchase of additional reagents is necessary.

 

Is the Taq included in the kit an antibody hot-start enzyme?
The PowerPlex S5 PCR reaction is indeed hot-start in nature. However, the method to achieve hot-start is different than that used in antibody-based hot start enzymes. The reaction buffer includes Promega's Taq DNA Polymerase and a mixture of single-stranded DNA binding proteins. The DNA binding proteins sequester the amplification primers, preventing primer extension during reaction set-up. Heating the reactions in a thermal cycler denatures the DNA binding proteins, liberating the primers and allowing primer extension to occur. This is the same technology used in Plexor^® HY dual quantification system for forensic casework.