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Ultrahigh Speed Direct PCR, A Method for Obtaining STR Genotypes in 6 Minutes

NCJ Number
Date Published
February 2020
13 pages
This project's goal was to develop rapid, direct screening methods for forensic DNA typing that are capable of amplification rates as fast as 6 minutes.

It is often important to rapidly screen suspects who may have been involved in a crime, especially when time is critical or when a large number of samples must be quickly processed. These situations require rapid screening of DNA samples. Although current DNA typing methods provide the best biometric information on identity, kinship, and geographical origin, they are not sufficiently fast to permit the identification of a suspect's DNA in real time. Rapid polymerase chain reaction (PCR) procedures can greatly speed the processing time of forensic samples because of the newly designed fast polymerases, particularly when combined with newly developed rapid thermocyclers and microfluidics. Using the described experiments, the current project achieved multiplexed STR amplifications as fast as 6.5 minutes, using extracted DNA, and 8.5 minutes, using direct PCR of diluted saliva with no extraction. The project used high-speed thermal cyclers in examining a variety of rapid polymerases, with the intent of producing multiplex PCR amplification of STRs faster than previously reported. Analysis was done by standard capillary-based methods, as well as by using a specially modified microfluidic system (dual laser Agilent 2100 with heat plate) capable of 80-second high-resolution separations. Project results can be used to develop quick screening of suspects at ports of entry or for identification in criminal casework. 8 figures, 1 table, and 25 references

Date Published: February 1, 2020