Single nucleotide polymorphisms (SNPs) are associated with the development of 
certain types of cancer. The present study aimed to investigate the association 
between X-ray repair complementing defective repair in Chinese hamster cells 2 
(XRCC2) SNPs and colorectal cancer (CRC) cell sensitivity to the 
poly(ADP-ribose) polymerase (PARP) 1 inhibitor olaparib (AZD2281). SNaPshot® 
analysis of XRCC2 SNPs was performed in five CRC cell lines. The 
AZD2281-sensitivities of the CRC cells were also analyzed using MTT assays. The 
effect of AZD2281 on XRCC2 and PARP1 expression was investigated in the five 
cell lines using quantitative polymerase chain reaction and western blot 
analyses. Parallel investigations were performed using a cisplatin (DDP) model 
of DNA damage. The XRCC2 rs3218536 SNP was found to be associated with the LoVo 
microsatellite instability CRC cell line. The relative rate of growth inhibition 
was found to be lower in the LoVo cells following treatment with AZD2281 
compared with the other four cell lines (P=0.002). Furthermore, the XRCC2 mRNA 
level in the LoVo cells was observed to be significantly higher than that in the 
other four cell lines (P<0.05). Similar results were found using the DDP model 
of DNA damage (P<0.05). The present study indicated that the XRCC2 rs3218536 
polymorphism decreases the sensitivity of CRC cells to AZD2281.