Kenya's wildlife is in decline in part due to poaching of commercially valuable species. In many areas, poaching in the form of snaring is commonplace, largely due to a lack of resources, food insecurity and poverty. Increased poaching effort has reportedly led to an increase in bushmeat in Kenya's markets and butcheries.
Bushmeat is legal in some African countries but is illegal in Kenya. Once bushmeat as been processed, it is indistinguishable from domestic meat. Therefore DNA analysis is required to determined if the meat sold, labeled as beef, pork, goat or lamb, is actually wildlife meat. We will be testing several samples to ascertain the species of origin.
Please read over the summary below from a report entitled "Lifting the Siege: Securing Kenya's Wildlife."
![]() Review "Lifting the Siege" and the Bushmeat Report Summary |
Our samples are from the Taita Taveta district of southeastern Kenya, which includes Kenya's largest national park system, Tsavo East and Tsavo West National Parks. Specifically, our samples are from the Kasigau area between the two parks, located on the trailing edge of the Eastern Arc Mountains. The Kasigau landscape is dominated by Mt. Kasigau, which the Titata people settled around to serve as a water catchment. The area also serves as a migration corridor between Tsavo East and West National Parks and is rife with human wildlife conflict.
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1) Bushmeat Processing |
2) Digestion & Extraction |
3) Polymerase chain reaction (PCR) |
4) Gel electrophoresis |
5) Sequencing |
6) BLASTing |
Lab 10: ProtocolYour task in Lab 10 is to replicate a DNA extraction protocol and determine how much DNA we have successfully extracted form our samples and how much DNA we have following PCR.
Exercise I. How do you extract DNA? Exercise II. Determine How Much DNA We Have After Extraction Exercise III. Determine How Much DNA We Have After PCR |
Procedure
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Exercise II. How much DNA do we have?Now, let's move on to our own samples. Following extraction of DNA from the meat samples, we need to determine how much DNA we have. In other words...we're we successful and to a high enough degree to allow for the next steps?
Proceedure: Estimate the number of DNA fragments (our gene of interest, cytochrome b) we may have by the end of PCR.
1) We start here! Following DNA extraction, we test the amount of purified DNA in our samples, to ensure enough product exists for PCR to work. We conduct this analysis using a spectrophotometer. The results for our samples are shown in the figure at right in ug/ng. Sample 8 yielded no genetic material.
2) How much cytochrome b (cytb) DNA might we have? Using these results calculate the potential total number of cytochrome b (cytb) fragments we have extracted from each sample.
Wait! Why are we looking for the cytochrome b gene? All DNA is NOT the same. Some genes are more conserved than others. The DNA for life, is very similar. For example we share 50% our DNA with bananas. Within our species, we share 99.%. The genes that can be used to distinguish between mammal species are specific. Cytochrome b is one such gene. The sequence of As, Cs, Ts and Gs can tell us from which species it originated. So now our task is to determine out of all the DNA we have extracted, approximately how much if the cytochrome b gene do we have?
You need the following to make your calculations:
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