Despite growing evidence of the clinical potential of DNA methylation, many inconsistent results can be observed across studies. Hence, this study was undertaken to consolidate information on the clinical potential of methylation in GC by means of a meta-analysis, and to suggest which candidate methylation events deserve further evaluation as clinically relevant biomarkers for the disease. Numerous studies have implicated aberrant DNA methylation at numerous genes in different samples and models of gastric tumourigenesis. This implication has in turn given rise to the notion that methylation could be a useful biomarker for improving the clinical management of GC. To date however, this potential has not been realized, presumably due to a lack of relevant evidence to support the testing of methylation in the clinic. In this study, a comprehensive review of all publications on the frequencies and 4-(Benzyloxy)phenol Associations of methylation in gastric cancer clinical samples was performed to consolidate information in the field. Meta-analyses were conducted where possible to gain an objective consensus from repeatedly investigated events. From the analysis, lists were generated of genes significantly differentially methylated between tumour and normal tissue sample from GC subjects, and normal tissue and/or blood from GC and non-cancer subjects, each with methylation events annotated for their strength of association and frequency of analysis. Findings from studies on the prognostic and predictive significance of methylation events were also reviewed. These lists and additional supplementary data should provide useful information from which to better assess the clinical potential of the respective events, and prioritize further work. From the perspective of risk markers however, these events can only be considered a first pool of candidates to test further in more clinically relevant analyses, as the events on their own only identify gastric tumour samples that are already histologically diagnosable. A number of events were in common between studies on normal tissue and blood, such as methylation at p16, CDH1, DAPK. These events are clinically promising, as they demonstrate discriminative capabilities for estimating GC risk from samples that can be obtained in current routine practice, such as during endoscopic screening, or population or clinical screening. The hypothesis that gene silencing by methylation may also determine severity of disease has also prompted numerous investigations of gene methylation associations with survival in GC. In this review, 28 studies reporting on the association of survival of GC subjects and methylation at 40 genes were also identified. In support of the hypothesis, numerous UNC0379 significant associations between methylation and poor survival were recorded, primarily at tumour suppressor genes. Associations between methylation and better survival were also reported for four genes, presumably reflecting that suppression of oncogenic activity.