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Updated: Feb 6, 2026

Genotyping Single Nucleotide Polymorphisms in the Mitochondrial Genome by Pyrosequencing
Published on: February 10, 2023
Association between XRCC1 single-nucleotide polymorphisms and susceptibility to nasopharyngeal carcinoma: An update
Juan Lin1, Qing Ye, Yihong Wang
1Department of Otorhinolaryngology Department of Laboratory, Provincial Clinical College of Fujian Medical University, Fujian Provincial Hospital, Fuzhou, Fujian, China.
Background:
Many studies have investigated polymorphisms of X-ray repair cross-complementing protein 1 (XRCC1) and risk of nasopharyngeal carcinoma (NPC), but the results are somewhat contradictory in different studies. There is an urgent need to keep in step with the relevant observational studies to more comprehend the effects of XRCC1 variants on the NPC risk.
Methods:
A systematic literature search accompanied with meta-analysis was carried out to obtain a detailed evaluation on the association between XRCC1 polymorphisms and NPC risk.
Results:
Meta-analyses showed that there was no statistically significant association observed between Arg194Trp/Arg280His variants in the XRCC1 gene and NPC risk with all genetic models, when relatively larger samples were pooled into the update meta-analysis. The reassessment suggested NPC risk was significantly increased with Arg399Gln polymorphism. The significant association was identified in homozygous, recessive, and allelic models, more than previously reported.
Conclusion:
We confirmed that Arg399Gln polymorphism of XRCC1 gene is a potential predictor for susceptibility to NPC, especially for Asians. More studies are required to evaluate the association in different populations.
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