New Promega Chemistry Will Enable Forensic DNA Labs to Solve More Challenging Cold and Sexual Assault Cases
Eight-color STR multiplex system provides more information per casework sample
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Introduction
New chemistry for DNA analysis will empower forensic laboratories to overcome common challenges including degraded and contaminated samples. PowerPlex® 35GY System, launched today by Promega Corporation, is a first-of-its-kind eight-color DNA analysis kit that helps forensic laboratories get more information out of their most challenging samples. The kit works in tandem with Spectrum CE System, a capillary electrophoresis instrument launched by Promega in 2022. “Together, PowerPlex® 35GY System used with Spectrum CE System provide the most advanced forensic analysis available,” says Rohaizah James, Senior Product Manager at Promega. “The eight-color chemistry used in PowerPlex® 35GY System gives more information per sample, even with degraded DNA.”
Next-generation eight-color STR kit
PowerPlex® 35GY System is the first of a series of next-generation eight-color STR kits that Promega is producing to take full advantage of the Spectrum CE System’s eight-color capability. The biotechnology manufacturer has been developing and providing products for DNA-based human identification for more than 25 years. Short tandem repeat (STR) analysis is the most widely used tool in human identification efforts. Currently available kits rely on five or six colors of dyes to mark regions of DNA that can help identify a match. PowerPlex® 35GY System is the first STR multiplex to include eight dyes. This major improvement in chemistry is made possible by the Spectrum CE System, the first commercially available capillary electrophoresis instrument equipped for eight-color fragment analysis.
“Mini-STRs” for enhanced resolution
PowerPlex® 35GY System includes the amplicons of 15 loci that have been reduced in size to less than 250 base pairs in length. These “mini-STRs” are less likely to “drop out” or disappear during STR analysis, which helps ensure data is not lost. This is especially important in cold case samples where DNA may be degraded or where there may be a limited amount of sample to work with.
Y-STRs for sexual assault investigation and familial searching
PowerPlex® 35GY System is also ideal for working with sexual assault samples or for identifying unknown matches through familial searching. The kit includes 11 STR loci that are located on the Y-chromosomes. These Y-STRs, along with the increased sensitivity of the kit, can help labs more easily determine how many individuals’ DNA are present in a sample.
Quality Indicators for Improved Efficiency
Finally, PowerPlex® 35GY System includes two Quality Indicators to help forensics labs work efficiently by quickly identifying sources of failure. These indicators let DNA analysts quickly determine if a sample is degraded or if there was a problem during their analysis. This information can help labs decide if they need to re-analyze samples or if they should move on to the next sample. By combining these Quality Indicators with the high-throughput capabilities of Spectrum CE System, PowerPlex® 35GY System can help forensics labs efficiently work through their sexual assault kit backlog, for example.
Download: The Power of 8 Colors – Next Generation CE STR Analysis
The ability to detect 8 colors with the new Spectrum CE System allows for the development of 8-color STR systems with more loci as smaller amplicons for better performance with degraded and inhibited samples. The 8-color PowerPlex® 35GY System combines the CODIS 20 core loci along with Penta D, Penta E, SE33 and ten Y STR markers for familial searching and analysis of sexual assault evidence.