Whilst this study has focussed on bTB excretion in badgers, the same methodology could be applied for monitoring M. bovis in other wildlife species, both those thought to be reservoirs as well as potentially vulnerable species. To conclude, this ring trial has validated the potential use of this quantitative molecular tool applied to environmental samples, and shown that with spiked samples the test is both reliable and reproducible. With natural samples there was also a high level of concordance between laboratories. This is the first example of a multi-laboratory validation of a real time PCR assay for detection of pathogens in environmental samples. Studies are now required to determine sampling protocols to best apply the assay in the field for purposes of population-level bTB surveillance. Gastric cancer remains a major clinical challenge worldwide due to its high prevalence, poor prognosis and Acetrizoic acid limited treatment options. Although the incidence of GC has declined over the years, it continues to be the second leading cause of cancer death and the fourth most common Pyriproxyfen malignancy worldwide. Less than 25% of GC cases are diagnosed at an early stage, and the 5-year survival rate is only 24% in the US and Europe. However, the survival rate from GC improves to over 60% if detected at an early stage, emphasizing the importance of early detection in this cancer type. DNA methylation is an epigenetic mechanism of transcriptional regulation, with an involvement in cancer attributed to the inappropriate silencing of tumour suppressor genes, or loss of oncogene repression. Since the first article by Fang et al. in 1996 describing DNA hypomethylation of c-myc and c-Ha-ras in GC, more than 550 studies have been published on the involvement of aberrant DNA methylation in the development of GC. As a result, the presence and functional consequences of aberrant DNA methylation of more than 100 genes in GC has been reported. Evidence on links between aberrant DNA methylation to H. pylori infection and its involvement in precancerous gastric epithelial lesions and GC progression are also being increasingly documented. Taken together, these results have indicated aberrant DNA methylation has a significant role in gastric cancer development and progression. The pattern of tumour DNA methylation can be useful for cancer risk screening, prognostication and treatment prediction. Compared to somatic mutation, DNA methylation has a higher number of aberrant alterations per cancer cell. Moreover, aberrant DNA methylation occurs early in the tumourigenesis of many cancer types, making it particularly useful for risk prediction. The technical attraction of DNA methylation is that it is chemically stable and can be detected with a very high sensitivity of up to 1:1000 molecules. Several reports have also demonstrated that cancer-specific, methylated DNA can be found in biological fluids, suggesting it could be a useful marker for non-invasive diagnosis.