Investigating the Ku70 (XRCC6) gene polymorphism in patients with gastric cancer

Year 2025, Volume: 39 Issue: 2, 111 - 126, 20.05.2025

Sezin Canbek

https://doi.org/10.18614/dehm.1699431

Abstract

BACKGROUND
The DNA repair gene Ku70, a key component of the non-homologous end-joining repair pathway, plays a crucial role in the repair of DNA double strand breaks (DSBs). Deficiencies in DSB repair may result in permanent genomic instability. However, the association between polymorphic variations of Ku70 and susceptibility to gastric cancer remains unclear.

OBJECTIVE
This study aims to investigate the potential correlation between the Ku70 promoter G-57C (rs2267437) and intron 3 (rs132774) polymorphisms and the risk of developing gastric cancer in the Turkish population.

METHOD
A hospital-based case-control study was conducted, including 92 patients diagnosed with gastric cancer and 194 age- and gender-matched healthy controls. Genotyping of Ku70 promoter G-57C (rs2267437) and intron 3 (rs132774) polymorphisms was performed using real-time PCR at Dokuz Eylül University Hospital, Izmir.

RESULTS
No significant difference was observed in the distribution of genotype frequencies for either polymorphism between the gastric cancer patients and the control group. The Chi-Square test revealed no significant difference in the frequencies of the G-57C (rs2267437) polymorphism between the cancer group and the control group. The CC genotype was absent in the cancer group, while it was present in one in the control group. The GG genotype of intron 3 (rs132774) polymorphism was also absent in both groups. The Chi-Square test revealed no significant difference between the two groups.

CONCLUSION
The presence of the Ku70 promoter G-57C (rs2267437) and intron 3 (rs132774) polymorphisms does not appear to increase the risk of gastric cancer in the Turkish population.

Keywords

Case-control study , DNA repair , gastric cancer , Ku70 gene , polymorphisms

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