Genetic type Coefficient Standard Error Arg/Arg vs Pro/Pro Arg/Arg+Arg/Pro vs Pro/Pro Arg/Arg vs Arg/Pro+Pro/Pro 2.757 1.172 2.726 1.0434 0.659 1.183 written in English or Chinese were searched. Moreover, although papers written in some other languages, cited by PubMed, were also searched, it is possible that some related published or unpublished studies that might meet the inclusion criteria were missed. Hence, some inevitable publication biases might exist in the results, though the Nfs0.05 showed no remarkable publication biases in the meta-analyses. Second, in the subgroup analysis, the number of studies regarding Africans was relatively lim- ited. It may be underpowered to explore the real associa- tion. Thus, the results may be interpreted with caution. Third, whether the experimental and control groups were from the same socio-economic status or the same geo- graphic area have not been clearly presented in some of the included original papers, leading to any possible biases. Furthermore, the sample sizes of some included studies are rather small, which might be one of the rea- sons contributing to the between-study heterogeneity. Therefore, a number of further studies with large sample sizes with well-matched controls are required. Besides, gene-gene and gene-environment interactions should also be considered in the further studies. In summary, despite the limitations, the results of the present meta-analysis suggest that genetic variations of TP53 codon 72 may not have a marked association with breast cancer risk. Competing interests The authors declare that they have no competing interests. Authors' contributions WZ and YZ conceived of the study, and carried out the analysis of the literatures and drafted the manuscript. ZX carried out the collection of the literatures. LC helped with the statistical analysis and manuscript drafting. ZC and WZ conceived of the study, and participated in its design and coordination and helped to draft the manuscript. 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