Microbial diversity manifests differently in different ecological niches of the body, with greater diversity generally expected in the gut, given that different locations have unique roles to play in the digestive system. Most microbial research is conducted using fecal samples, meaning the resulting microbes come from various places all throughout the intestines and not specific locations. The Integrative Human Microbiome Project (HMP2), provides a unique opportunity to study microbiomes of both the rectum and ileum through the use of biopsy samples taken from both locations. Using the data provided the microbiome compositions of the rectum and ileum were able to be studied and analyzed to showcase how those microbes associated with clinical variables. Inflammatory bowel diseases are complex diseases that are heterogeneous at clinical, immunological, molecular, genetic, and microbial levels. While it is known that those affected by these diseases have microbiomes that differ from those with healthy guts, not much is known about which changes in the microbiome represent causes rather than effects from changes in health.

The use of DNA testing has been focused primarily on biological samples such as blood or saliva found at crime scenes. These types of evidence in the forensic field are sometimes difficult to come by, especially when there is no body to find to verify things such as identity or status of a person. In the case of the burial of a body, they can be remote and relocated multiple times depending on each situation. Clandestine burials are not uncommon especially in the Arizona desert by the United States and Mexico border. Since there is no physical body to find the next best avenue to finding a clandestine burial is through search teams which can take weeks to months or other expensive technology such as ground penetrating radar (GPR). A new more interesting avenue to search for bodies is using the most found material–soil. Technology has allowed the possibility of using soil DNA microbiome testing initially to study the varieties of microbes that compose in soil. Microbiomes are unique and plentiful and essentially inescapable as humans are hosts of millions of them. The idea of a microbiome footprint at a crime scene seems out of reach considering the millions of species that can be found in various areas. Yet it is not impossible to get a list of varieties of species that could indicate there was a body in the soil as microbiomes seep through from decomposition. This study determines the viability of using soil microbial DNA as a method of locating clandestine graves by testing 6 different locations of a previous pig decomposition simulation. These two locations give two different scenarios that a body may be found either exposed to the sun in an open field or hidden under foliage such as a tree in the Sonoran Desert. The experiment will also determine more factors that could contribute to a correlation of microbiome specific groups associated with decomposition in soil such as firmicutes. The use of soil microbial DNA testing could open the doors to more interpretation of information to eventually be on par with the forensic use of biological DNA testing which could potentially supplement testimonies on assumed burial locations that occurs frequently in criminal cases of body relocation and reburial.