Identifying endangered species from degraded mixtures at low levels

Although endangered species are afforded protection under national and international laws, trade in products containing endangered species is still one of the most lucrative criminal enterprises in the world. Forensic science is employed to determine if endangered species are present in commercial products but runs into problems due to the extremely low levels of DNA and degraded nature of the majority of samples. Therefore a section of the mitochondrial genome is generally amplified and sequenced to determine if endangered species are present. This technique is sensitive and accurate, but cannot identify components of a DNA mixture due to the use of universal primers and can fail with subcellular levels of DNA. A multiplex PCR was therefore developed, based on the cytochrome b and 12S rRNA genes, to identify the presence of endangered mammalian species, if present, in commercial products. Four species [tiger (Panthera tigris ssp.), leopard (Panthera pardus), musk deer (Moschus sp.) and Asiatic black bear (Ursus thibetanus ssp.)] in addition to several common non-protected mammalian species can be identified using species-specific primers. A specific PCR product is produced depending on which species is/are present. The test is accurate and sensitive to low levels of DNA. It has been tested using traditional East Asian Medicine claiming to contain one or more endangered mammalian species. The test can be performed using standard DNA analysis techniques and implemented by any laboratory with these facilities.