MicroGEM’s forensicGEM™ Sperm lysis kit uses a novel cocktail of temperature-controlled enzymes to rapidly degrade sperm heads and digest the remaining tissue and nucleases in the sample. Our temperature-controlled DNA extraction process allows for lysis without purification and uses no reducing agents, such as DTT, that inhibit qPCR and STR analysis. As a result, DNA yields are maintained, processing time is quick, and opportunities for contamination are minimized making this the perfect approach for differential extractions and y-screening.
Sperm cells are a difficult type of cell to lyse, often requiring qPCR and STR-inhibiting chemicals such as SDS, mercaptoethanol and DTT, to lyse sperm cells. These chemicals are toxic to downstream processes and must be removed via purification steps. These steps are time-consuming and result in a loss of DNA. It is not possible to work with very small numbers of cells since DNA is lost at every step.
The forensicGEM™ Sperm kit uses a unique mixture of thermophilic and mesophilic enzymes with no purification steps required. At low temperatures, mesophilic cell wall degrading enzymes rapidly degrade sperm heads. The 75° step then activates a thermophilic proteinase that lyses the cells, kills nucleases and strips the DNA of nucleosomes. A final 95° step deactivates the thermophilic proteinase, producing single-stranded DNA perfect for qPCR and STR amplification.
Acoustic Trapping of Sperm Cells from Mock Sexual Assault Samples Using forensicGEM Sperm (view abstract)
The prototype acoustic trapping technology, developed at the University of Virginia, isolated intact sperm cells from mock samples containing a 40-fold excess in female epithelial cells over sperm cells. forensicGEM Sperm was used to rapidly lyse sperm cells with no purification steps. Downstream PCR amplification resulted in male-only profiles.
forensicGEM Sperm lysis has been validated for Y Screening
Read the NYC Office of the Chief Medical Officer protocol for Y Screening.