Submitted to: Patent Application
Publication Type: Other
Publication Acceptance Date: 8/15/2005
Publication Date: 8/17/2005
Citation: Lunney, J.K., Jauregui, L.H., Higgins, J.A., Zarlenga, D.S., Dubey, J.P. 2005. Polymerase chain reaction assay for detection of toxoplasma gondii. United States Patent #6,770,440, issued August 3, 2004. http://www.ars.usda.gov/research/patents.htm?serialnum=09867435. Interpretive Summary: ARS researchers have developed a Polymerase Chain Reaction (PCR) assay that can detect Toxoplasma gondii (T. gondii), a food-borne parasite, found in meat or meat products. This new PCR test can be used in slaughter house monitoring for food safety testing. This very specific, rapid test can detect the DNA from just one parasite. Undercooked pork is the most common source of food borne transmission to humans in the United States, although lamb is also a common source, particularly in Europe and Australia. People with suppressed immune systems are more at risk to T. gondii infection. Current detection methods include time-consuming techniques that require tissue culture, and bioassays are not easy to use for wide-scale commercial testing of meat products. This invention could be used for testing carcasses or the meat products themselves for supermarket product screening. This test also has biomedical and human applications to test for T. gondii infections. It could also be applied to test for T. gondii presence in animal tissue to test for vaccine success.
Technical Abstract: Oligonucleotide primer sequences have been designed which are capable of uniquely amplifying DNA from Toxoplasma gondii when utilized in a polymerase chain reaction assay. In addition, a probe effective for detection of amplification products, particularly in a fluorogenic real time assay system has also been designed. The primers and probe are derived from the internal transcribed spacer 1 (ITS1) region of the T. gondii 18S rRNA gene.