Association of XRCC1 Arg399Gln Polymorphism with Colorectal Cancer Risk: A HuGE Meta Analysis of 35 Studies.
BACKGROUND
Non-synonymous polymorphisms in XRCC1 hase been shown to reduce effectiveness of DNA repair and be associated with risk of certain cancers. In this study we aimed to clarify any association between XRCC1 Arg399Gln and colorectal cancer (CRC) risk by performing a meta-analysis of published case-control studies.


METHODS
PubMed and Google Scholar were searched to explore the association between XRCC1 and CRC. Odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the association strength. Publication bias was assessed by Egger's and Begg's tests.


RESULTS
Up to January 2015, 35 case control studies involving 9,114 CRC cases and 13,948 controls were included in the present meta-analysis. The results showed that the Arg399Gln polymorphism only under an allele genetic model was associated with CRC risk (A vs. G: OR 0.128, 95% CI 0.119-0.138, p<0.001). Also, this meta-analysis suggested that the XRCC1 Arg399Gln polymorphism might associated with susceptibility to CRC in Asians (A vs G: OR 0.124, 95% CI 0.112-0.138, p<0.001) and Caucasian (A vs G: OR 0.132, 95% CI 0.119-0.146, p<0.001) only under an allele genetic model.


CONCLUSIONS
This meta-analysis confirms the association between XRCC1 Arg399Gln polymorphism and CRC risk and suggests that the heterogeneity is not strongly modified by ethnicity and deviation from the Hardy-Weinberg equilibrium.
Department of Internal Medicine, Shahid Sadoughi Training Hospital, Shahid Sadoughi University of Medical Sciences and Health Services, Yazd, Iran E-mail : gholi.nataj.m@gmail.com.
Mohammad
M
Forat-Yazdi
Mohsen
M
Gholi-Nataj
Hossein
H
Neamatzadeh
Parisa
P
Nourbakhsh
Hossein
H
Shaker-Ardakani
D000483:Alleles; D044466:Asian People / Q000235:genetics; D015179:Colorectal Neoplasms / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics*; D020022:Genetic Predisposition to Disease; D006801:Humans; D011110:Polymorphism, Genetic; D044465:White People / Q000235:genetics; D000076105:X-ray Repair Cross Complementing Protein 1
D004268:DNA-Binding Proteins; D000076105:X-ray Repair Cross Complementing Protein 1; C000619371:XRCC1 protein, human