Association of 8q24.21 loci with the risk of colorectal cancer: A systematic review and meta-analysis

Research Center for Gastroenterology and Liver Disease, Shaheed Beheshti University, Tehran, Iran.
Journal of Gastroenterology and Hepatology (Impact Factor: 3.5). 07/2011; 26(10):1475-84. DOI: 10.1111/j.1440-1746.2011.06831.x
Source: PubMed


Recent genome-wide association studies of colorectal cancer (CRC) have identified rs6983267 and trs10505477 polymorphisms as key loci in the 8q24 region to be associated with CRC. In the present study, we performed a meta-analysis to determine whether these loci are risk factors for susceptibility to CRC.
We meta-analyzed the 22 included studies (47 003 cases and 45 754 controls) that evaluated the association of rs6983267 and trs10505477 with CRC under alternative genetic models.
A meta-analysis of the pooled data showed allelic and genotypic association of the rs6983267 polymorphism with CRC risk in Asians, Europeans, and European-Americans. A subanalysis of the US studies showed negative results in the studies with non-identified ethnicity of the patients. A meta-analysis of included studies of rs10505477 polymorphisms identified allelic and genotypic associations with CRC risk in the US patients. A further meta-analysis of the US studies demonstrated positive results in the studies with non-identified ethnicity of the samples.
Our data suggested that the rs6983267 G > T polymorphism is a risk factor for CRC in Asians, Europeans, and Americans with European ancestry.

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