Buccal swabs have been used for decades as an economical method to obtain biomaterials suitable for genomic DNA extraction for use in forensics and molecular epidemiology studies. Using buccal swabs, as opposed to methods such as saliva collection or rinsing with mouthwash, was considered sub-optimal as they contained large quantities of microbial DNA. As there is roughly an order of magnitude more non-human than human cells in our bodies, a large proportion of non-human DNA in many biospecimens is to be expected. While some bacteria are pathological, many carry out important functions or protect the body. The complex interactions between environmental factors, the human microbiome, and the human host can provide important clues with respect to various diseases and response to treatment. Advances in technology with respect to DNA sequencing allow for not only highly accurate determination of specific strains of bacteria but also the detection of very low proportions of those strains in biological samples. Similarly, advanced techniques such as mass spectroscopy provide information as to how changes in the microbiome and/or the host influence overall metabolism. These techniques have opened the door for a new wave of interest in the microbiome and its influence on metabolism and human health.

Citation Format: David Cox. New specimens: Buccal cells, nasal swabs, fecal samples. [abstract]. In: Proceedings of the AACR Special Conference on Post-GWAS Horizons in Molecular Epidemiology: Digging Deeper into the Environment; 2012 Nov 11-14; Hollywood, FL. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2012;21(11 Suppl):Abstract nr IA02.