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To assess systematically whether potentially functional polymorphisms in DNA repair genes influence the clinical behavior of non-small-cell lung cancer (NSCLC), we examined the impact of a comprehensive panel of 218 signal nucleotide polymorphisms (SNP) in 50 candidate DNA repair genes on overall survival of NSCLC in a case-cohort of 568 lung cancer patients. SNPs associated with lung cancer prognosis primarily mapped to 14 genes in different repair pathways, and 6 SNPs were remained in the final model after multivariate stepwise Cox regression analysis: ATM rs189037; MRE11A rs11020802; ERCC2 rs1799793; MBD4 rs140693; XRCC1 rs25487, and PMS1 rs5742933. In the combined analysis of these 6 SNPs, an increasing number of unfavorable loci was associated with a poorer prognosis (P for trend

Genetic variants in DNA repair enzymes contribute to the susceptibility to cutaneous melanoma; consequently, we analyzed whether common nonsynonymous single-nucleotide polymorphisms in DNA repair enzyme genes might also influence the course of disease. To this end, we determined eight polymorphisms of seven different DNA repair enzymes in 742 patients with cutaneous melanoma, and correlated these with overall survival. Univariate Cox proportional hazards model analyses revealed that ERCC5 (XPG) 1104 His/His was significantly associated with impaired survival. Indeed, the univariate hazard ratio (HR) was 2.8 times higher for patients with ERCC5 1104 His/His (P

Aim To make an accurate estimation of the association of ERCC1 and ERCC2 polymorphisms with osteosarcoma (OS) prognosis in Chinese population. Methods Total 7 qualified studies with 1404 osteosarcoma patients were included. Odds ratios (OR) with 95% CIs were pooled for the survival rate in different osteosarcoma patients with ERCC1 and ERCC2 genetic polymorphisms. The heterogeneity was assessed by I test. Potential publication bias was assessed by Begg funnel plot and Egger linear regression test. Results In rs11615, no significant association was found under dominant [TT+TC vs. CC: OR = 1.252, 95% CI:0.864-1.815, P = .235], recessive [TT vs. TC+CC: OR = 0.850, 95% CI: 0.695-1.030, P = .095] or allelic model [T vs. C Allele: OR = 1.219, 95% CI: 0.922-1.612, P = .165]. In rs13181, no significant association was found under dominant [AA+AC vs. CC: OR = 1.031, 95% CI: 0.800-1.329, P = .801], recessive [AA vs. AC+CC: OR = 1.005, 95% CI: 0.875, 1.154, P = .944] or allelic model [A vs. C Allele: OR = 1.009, 95% CI: 0.903-1.128, P = .870]. In rs1799793, no significant association was found under dominant [GG+GA vs. AA: OR = 1.134, 95% CI: 0.884-1.454, P = .322, recessive [GG vs. AG+AA: OR = 1.025, 95% CI: 0.881-1.192, P = .750], or allelic model [G vs. A Allele: OR = 1.046, 95% CI: 0.930-1.177, P = .450]. Conclusion This study did not support rs11615, rs13181 or rs1799793 to be used as surrogate markers for clinical outcome of osteosarcoma with chemotherapy.

Studies investigating the association between excision repair cross-complimentary group 2 (ERCC2) polymorphisms and gastric cancer (GC) risk have reported conflicting results. We performed a meta-analysis of published epidemiological studies to derive a more precise estimation of the relationship.Published literature from PubMed, EMBASE, and China National Knowledge Infrastructure was retrieved. Ten studies with 2,141 GC cases and 5,343 controls were selected.No association between ERCC2 Lys751Gln polymorphism and GC susceptibility for all genetic models was found. When stratified by race, we found the Gln/Gln genotype carriers might be at high risk of GC among Asians, but not among Caucasians. Also, the pooled results showed there was a significant difference in genotype distribution between non-gastric cardia cancer cases and controls. For ERCC2 Asp312Asn polymorphism, significantly elevated GC risk was associated with Asn/Asn genotype (AA vs. GG + GA: OR = 1.36, 95%CI = 1.04-1.77, P = 0.02). We also found this genotype was associated with GC susceptibility among Asians and subjects without Helicobacter pylori infection. No publication bias was found in the present study.This meta-analysis concluded that both ERCC2 Lys751Gln and Asp312Asn polymorphisms might contribute to increased risk of GC among Asians.

Recent advances in human genome studies have opened new avenues for the identification of susceptibility genes for many complex genetic disorders, especially in the field of rare cancers such as glioma. To date, eight glioma susceptibility loci have been identified by candidate gene-association studies: PRKDC G6721T, XRCC1 W399R, PARP1 A762V, MGMT F84L, ERCC1 A8092C, ERCC2 Q751K, EGF +61 A/G, and IL13 R110G. Five loci have been identified by genome-wide association studies: TERT rs2736100, CCDC26 rs4295627, CDKN2A-CDKN2B rs4977756, PHLDB1 rs498872, and RTEL1 rs6010620. Using the Ingenuity Pathway Analysis tool, we investigated whether these 13 susceptibility genes are biologically related. Our data provide not only networks for understanding the biological properties of gliomagenesis but also useful pathway maps for future understanding of disease.

Inter-individual variations in treatment efficacy may be influenced by polymorphisms in DNA repair genes. We investigated the association of 3 functional polymorphisms in the nucleotide excision repair (NER) pathway with survival outcome of 95 patients with metastatic breast cancer (MBC) treated with DNA-damaging chemotherapy.ERCC1 8092 C/A, ERCC2 Asp312Asn and ERCC2 Lys751Gln were determined using Taqman-based genotyping assays. Genotype associations with breast cancer-specific survival (BCSS) and progression-free survival (PFS) were evaluated using Kaplan-Meier estimates and hazard ratios calculated using Cox regression analysis. Tests for trend were conducted by calculating P-values for the HR coefficient in proportional hazards regression models.ERCC2 Lys751Gln was significantly associated with BCSS (median: 24.8 months for AA/AC combined and 14.2 months for CC, HR: 1.9 (95% CI 1.06-3.26)). Median BCSS decreased with increasing number of designated adverse genotypes for the 3 polymorphisms (P (trend) = 0.003). Risk estimates for PFS were nonsignificantly elevated and were significantly elevated for BCSS for patients with 2 (HR = 2.21, 95% CI: 1.04-4.72) or 3 (HR = 6.67, 95% CI: 2.19-20.29) adverse genotypes. In treatment subgroup analysis, risk estimates for BCSS were significantly elevated for patients with 3 adverse genotypes treated with cyclophosphamide, mitoxantrone and vinblastine (HR: 11.9, 95% CI 1.77-79.51) and P (trend) = 0.02 for increasing number of adverse genotypes. Risk of progression was significantly increased for patients with 1 adverse genotype treated with cyclophosphamide, mitoxantrone and carboplatin (HR: 3.5, 95% CI 1.19-10.6) and P (trend) = 0.02 for increasing number of adverse genotypes.Polymorphisms in NER pathway may impact survival outcome for patients with MBC following treatment with DNA-damaging chemotherapy. These results provide support for a polygenic pathway approach for assessing the prognostic and predictive potential of polymorphisms in treatment outcome.

Trichothiodystrophy (TTD) is a rare (affected frequency of 1 in 106 in Europe) (1) autosomal recessive disorder of DNA repair and transcription (2–4). TTD has a wide spectrum of clinical features that include sulfur-deficient brittle hair, small stature, mental retardation, ichthyotic skin, unusual facial features and in some cases photosensitivity (5, 6). Laboratory confirmation of the diagnosis of TTD is based on analysis of hair samples, which show alternating dark and light banding (tiger-tail) on polarizing microscopy (7, 8), reduced sulfur content of hair shafts (7, 8), and tests of DNA repair (4). TTD is caused by mutations in a number of genes, some with known functions involved in DNA repair pathways and in transcription. Photosensitive TTD can be caused by mutations in at least three genes: XPD (ERCC2) and XPB (ERCC3) which encode the two helicase subunits of transcription factor TFIIH (9–11) and TTD-A (TFB5) which codes for the 10th subunit of TFIIH (12). TFIIH has various roles in several pathways including nucleotide excision repair (NER), basal transcription and activated transcription (13). Non-photosensitive TTD has been associated with mutations in TTDN1 (C7ORF11), a gene of unknown function on chromosome 7p14 (14, 15). Patients with defects in NER genes may have several different phenotypes in addition to TTD including xeroderma pigmentosum (XP), Cockayne syndrome (CS), cerebro-ocular-facial syndrome (COFS) or combinations of XP/TTD, XP/CS and COFS/TTD (3, 4). Patients with XP have increased freckle-like pigmentation of their skin and a 1000-fold increase in risk for cancers of sun exposed tissues (skin and eyes) without hair abnormalities (3, 4). COFS has been considered as a severe form of CS and is a progressive brain and eye disorder with varying severity of several abnormalities including mental and physical retardation (3, 16). Individuals diagnosed with XP/TTD or COFS/TTD have phenotypic features of both disorders and mutations in the XPD gene; the exact risk of other abnormalities associated with these combined diagnoses is not known (10, 17). Based on our novel clinical observations, we designed a genetic epidemiologic study in order to investigate pregnancy and human fetal developmental outcomes associated with defects in TTD genes. The specific objective of this study was to compare pregnancies resulting in TTD-affected individuals to pregnancies resulting in their unaffected siblings and to population reference values with respect to abnormalities noted during their antenatal and neonatal periods. For this purpose, obligate heterozygote (carrier) mothers of TTD patients referred to the National Institutes of Health (NIH) were interviewed regarding the course of the pregnancies that produced the TTD-affected and unaffected children.

Gene–environment interactions determine inter-individual variations in nucleotide excision repair (NER) capacity. Oxidative stress was previously found to inhibit NER, thus supplementation with dietary antioxidants could prevent this inhibition, especially in genetically susceptible subjects. To study the effects of genetic polymorphisms in NER-related genes and dietary intake of antioxidants on an individual's NER capacity, lymphocytes of 168 subjects were isolated before and after a 4-week blueberry and apple juice intervention. Twelve genetic polymorphisms in NER genesXPA,XPC,ERCC1,ERCC2,ERCC5,ERCC6andRAD23Bwere assessed by multiplex PCR with single base extension. Based on specific genotype combinations, a subset of individuals (n36) was selected for phenotypical assessment of NER capacity, which was significantly affected by the total sum of low-activity alleles (P = 0·027). The single polymorphismXPAG23A was the strongest predictor of NER capacity (P = 0·002); carriers of low-activity alleles AA had about three times lower NER capacity thanXPAGG carriers. NER capacity assessed before and after intervention correlated significantly (R20·69;P se6·61) to 805 (se7·90) μm(P = 0·032), on average it did not affect NER capacity. Nonetheless, carriers of twelve or more low-activity alleles seemed to benefit from the intervention (P = 0·013). Among these, carriers of the variant allele forRAD23BAla249Val showed improved NER capacity upon intervention (P = 0·020). In conclusion, improved NER capacity upon dietary intervention was detected in individuals carrying multiple low-activity alleles. TheXPAG23A polymorphism might be a predictor for NER capacity.

Lung cancer (LCa) is a multifactorial disease with exogenous and endogenous causes. Different variants in DNA repair gene, ERCC2, may influence individual’s susceptibility to this disease. This study aims to assess the impact of two single nucleotide polymorphisms (SNPs) in ERCC2 gene (r rs1799787 and s1799788) on susceptibility to LCa in a sample of Iraqi patients. A total of 60 his to logically confirmed patients with LCa and 40 family-unrelated, age- and sex-matched healthy individuals as a control group were recruited for this study. DNA was isolated from blood samples and ERCC2 gene was amplified with specific primers using conventional PCR. Genotyping was performed by direct sequencing. The mutant homozygous genotype (TT) of rs1799787 polymorphism was more frequent in patients than controls (12.67% vs 2.5%) with significant difference (OR=2.45, 95%CI= 1.07-5.92, P=0.046). Model analysis revealed a significant effect of the recessive model where CT+TT genotype was significantly higher in patients than controls (58.33% vs 30%). Furthermore, the frequency of the mutant allele (T allele) was significantly higher in patients than controls (OR=2.775, 95%CI=1.375-5.603, P=0.004). On the other hand, the SNP rs1799788 appeared no to have any association with LCa. These results strongly suggested the role of rs1799787 polymorphism on the susceptibility to LCa among the Iraqi population.

WHAT IS ALREADY KNOWN ABOUT THIS SUBJECT • Numerous clinical studies, including a few prospective ones, have reported conflicting results on the impact of gene polymorphisms related to fluorouracil (FU) and oxaliplatin pharmacodynamics. WHAT THIS STUDY ADDS • This prospective study is the first to report that clinical response to FOLFOX is significantly related to methylenetetrahydrofolate reductase (MTHFR) gene polymorphisms (677CT and 1298AC), with a response rate of 37, 53, 63 and 80% in patients harbouring no, one, two or three favourable MTHFR alleles, respectively. • Only polymorphisms of genes related to oxaliplatin pharmacodynamics (GSTπ 105IleVal and XPD 751LyGln) influenced progression-free survival. • These results corroborate the observation that response was related to the cumulative FU dose, whereas progression-free survival was related to the cumulative oxaliplatin dose. AIMS To test prospectively the predictive value of germinal gene polymorphisms related to fluorouracil (FU) and oxaliplatin (Oxa) pharmacodynamics on toxicity and responsiveness of colorectal cancer (CRC) patients receiving FOLFOX therapy. METHODS Advanced CRC patients (n= 117) receiving FOLFOX 7 therapy were enrolled. Gene polymorphisms relevant for FU [thymidylate synthase (TYMS, 28 bp repeats including the GC mutation + 6 bp deletion in 3'UTR), methylenetetrahydrofolate reductase (MTHFR, 677CT, 1298AC), dihydropyrimidine deshydrogenase (IVS14+1GA) and Oxa: glutathione S-transferase (GST) π (105IleVal, 114AlaVal), excision repair cross-complementing group 1 (ERCC1) (118AATAAC), ERCC2 (XPD, 751LysGln) and XRCC1 (399ArgGln)] were determined (blood mononuclear cells). RESULTS None of the genotypes was predictive of toxicity. Response rate (54.7% complete response + partial response) was related to FU pharmacogenetics, with both 677CT (P= 0.042) and 1298AC (P= 0.004) MTHFR genotypes linked to clinical response. Importantly, the score of favourable MTHFR alleles (677T and 1298C) was positively linked to response, with response rates of 37.1, 53.3, 62.5 and 80.0% in patients bearing no, one, two or three favourable alleles, respectively (P= 0.040). Polymorphisms of genes related to Oxa pharmacodynamics showed an influence on progression-free survival, with a better outcome in patients bearing GSTπ 105 Val/Val genotype or XPD 751Lys-containing genotype (P= 0.054). CONCLUSIONS These results show that response to FOLFOX therapy in CRC patients may be driven by MTHFR germinal polymorphisms.

Genetic variations in DNA repair genes are thought to modulate DNA repair capacity and are suggested to be related to lung cancer risk. We conducted a meta-analysis of epidemiologic studies on the association between genetic polymorphisms in both base excision repair and nucleotide excision repair pathways, and lung cancer. We found xeroderma pigmentosum complementation group A (XPA) G23A (odds ratio (OR)=0.76, 95% confidence interval (CI)=0.61–0.94), 8-oxoguanine DNA glycosylase 1 (OGG1) Ser326Cys (OR=1.22, 95% CI=1.02–1.45), and excision repair cross-complementing group 2 (ERCC2) Lys751Gln (OR=1.27, 95% CI=1.10–1.46) polymorphisms were associated with lung cancer risk. Considering the data available, it can be conjectured that if there is any risk association between a single SNP and lung cancer, the risk fluctuation will probably be minimal. Advances in the identification of new polymorphisms and in high-throughput genotyping techniques will facilitate the analysis of multiple genes in multiple DNA repair pathways. Therefore, it is likely that the defining feature of future epidemiologic studies will be the simultaneous analysis of large samples of cases and controls.

Although the etiology of primary brain tumors is largely unknown, prior studies suggest that DNA repair polymorphisms may influence risk of glioma. Altered DNA repair is also likely to affect the risk of meningioma and acoustic neuroma, but these tumors have not been well studied. We estimated the risk of glioma (n = 362), meningioma (n = 134), and acoustic neuroma (n = 69) in non-Hispanic whites with respect to 36 single nucleotide polymorphisms from 26 genes involved in DNA repair in a hospital-based, case-control study conducted by the National Cancer Institute. We observed significantly increased risk of meningioma with the T variant of GLTSCR1 rs1035938 (OR(CT/TT) = 3.5; 95% confidence interval: 1.8-6.9; P(trend) .0006), which persisted after controlling for multiple comparisons (P = .019). Significantly increased meningioma risk was also observed for the minor allele variants of ERCC4 rs1800067 (P(trend) .01); MUTYH rs3219466 (P(trend) .02), and PCNA rs25406 (P(trend) .03). The NBN rs1805794 minor allele variant was associated with decreased meningioma risk (P(trend) .006). Risk of acoustic neuroma was increased for the ERCC2 rs1799793 (P(trend) .03) and ERCC5 rs17655 (P(trend) .05) variants and decreased for the PARP1 rs1136410 (P(trend) .03). Decreased glioma risk was observed with the XRCC1 rs1799782 variant (P(trend) .04). Our results suggest that common DNA repair variants may affect the risk of adult brain tumors, especially meningioma.

More than 2,000 arsenic-related skin lesions (as at 2002) in a few villages of China’s Southwest Guizhou Autonomous Prefecture represent a unique case of endemic arseniasis related with indoor combustion of high-arsenic coal. The skin lesion prevalence was significantly higher in ethnic Han villagers than in ethnic Hmong villagers. This study was focused on a possible involvement of XPD/ERCC2 G23591A and A35931C polymorphisms in risk modulation of skin lesions and in the body burden of As in this unique case of As exposure. G23591A and A35931C were genotyped by a PCR-based procedure. Total As contents in hair and urine samples as well as environmental samples of the homes of the two ethnic clans were analysed. A significant higher presentation of A/A35931 (homozygous wild) genotype in both clans was found in skin lesion patients, compared with their asymptomatic fellow villagers (67.1 vs. 46.3%, OR 2.36, 95% CI 1.35–4.14, P = 0.002). Interestingly, the population frequencies of the A/A35931 genotype did not show significant differences between ethnic Han villagers and their Hmong neighbours (47.1 vs. 45.5%). Very low frequencies of homozygous and heterozygous variant genotypes of G23591A were recorded in the residents in target village. G/A23591 and A/A23591 were detected only in 3.2% (8/244) and 0.8% (2/244) of the villagers, respectively. The polymorphic status at the locus of A35931C might modulate the risk for arsenic-related skin lesions in the investigated groups.

Genetic polymorphisms in DNA repair genes can affect the risk of developing different forms of cancer. Therefore, we have studied the putative association of seven single nucleotide polymorphisms (SNPs) in five DNA repair genes with the incidence of chronic lymphocytic leukemia (CLL). We included 461 CLL patients and the same number of age- and sex-matched controls. As chromosomal aberrations are important prognostic markers in CLL, we additionally correlated the SNPs with the occurrence of favorable and unfavorable cytogenetic aberrations in CLL patients. Patients with del(13q) as a sole aberration were allocated to the favorable cytogenetic risk group, and patients with del(17p) and/or del(11q) to the unfavorable cytogenetic risk group. All investigated SNPs were equally distributed between patients with the favorable cytogenetic aberration and controls. However, differences were observed in the distribution of rs13181 in ERCC2 between all CLL patients and controls. Moreover, the clearest differences were found for rs13181 in ERCC2 and rs25487 in XRCC1 between CLL patients with unfavorable cytogenetic aberrations and controls. These data suggest that inborn genetic polymorphisms may predict the outcome of CLL.

Objective We sought to evaluate the affect of genetic polymorphisms on clinical outcomes in patients with epithelial ovarian cancer (EOC). Methods Clinical data of 118 patients between March 2001 and November 2006 were reviewed. They underwent staging laparotomy followed by adjuvant chemotherapy using taxanes and platinum compounds. We investigated ERCC1 N118N , ERCC1 8092C > A , ERCC2 K751Q , XRCC1 R399Q , XRCC1 R194W , ABCB1 3435C > T , ABCB1 2677G > T/A , GSTP1 I105V, GSTM1 and GSTT1 polymorphisms with single base primer assay. Results The multivariate logistic regression analysis revealed that non-null genotype in GSTT1 polymorphism was a poor prognostic factors for overall response (adjusted OR, 0.29; 95% CI, 0.17–0.67), and A/A genotype in GSTP1 I105V polymorphism and T/T or T/A or A/A genotype in ABCB1 2677G > T/A polymorphism were significant risk factors for grade 3 or 4 hematological (adjusted OR, 3.08; 95% CI, 1.12–8.43) and gastrointestinal toxicities (adjusted OR, 9.74; 95% CI, 1.59–15.85), respectively. Moreover, The multivariate Cox's proportional hazard regression analysis showed that C/A or A/A genotype in ERCC1 8092C > A polymorphism and non-null genotype in GSTT1 polymorphism were prognostic factors for poor progression-free survival (adjusted HR, 1.94; 95% CI, 1.07–3.51) and poor overall survival (adjusted HR, 1.65; 95% CI, 1.79–3.42), respectively. Conclusion Genetic polymorphisms such as ERCC1 8092C > A , ABCB1 2677G > T/A , GSTP1 I105V and GSTT1 polymorphisms may affect drug response, toxicity and survival in patient with EOC who received taxane- and platinum-based chemotherapy after surgery. However, large-scale, prospective clinical studies are required for evaluating the role of genetic polymorphisms.

DNA repair genes have been proposed as candidate cancer susceptibility genes. The excision repair cross-complementing rodent repair deficiency, complementation group 2 (ERCC2)/xeroderma pigmentosum complementary group D (XPD) protein is considered to be a key enzyme in nucleotide excision repair (NER) pathway. To elucidate whether common ERCC2 variants are associated with lung cancer susceptibility, we conducted a case― control study consisting of 339 cases with primary lung cancer and 358 controls matched on age, gender and ethnicity in a Chinese population. Six haplotype tagging single-nucleotide polymorphisms (htSNPs) (rs238403, rs50871, rs3916840, rs238415, rs3916874 and rs1799787) from HapMap database were analyzed, which provide an almost complete coverage of the genetic variations in the ERCC2 gene. Although none of the six htSNPs was individually associated with lung cancer risk, we found that two ERCC2 haplotypes were associated with risk of lung cancer. Haplotype 4 defined by rs238403T-rs50871T-rs3916840C-rs238415C-rs3916874G-rs1799787C and haplotype 7 defined by rs238403C-rs50871G-rs3916840C-rs238415C-rs3916874G-rs1799787C were strongly associated with an increased risk of lung cancer [odds ratio, OR (95% confidence interval, CI) = 2.62 (1.53-4.50), P = 0.0003 for hap4; OR (95% CI) = 3.01 (1.36―6.63), P = 0.004 for hap7]. Furthermore, diplotype analyses also strengthened the significant associations of risk haplotype 4 [OR (95% CI) = 3.56 (2.12―5.87), P < 0.001] or risk haplotype 7 [OR (95% CI) = 3.38 (1.75―6.55), P < 0.001] and lung cancer. Analysis of linkage disequilibrium (LD) also confirmed that considerable LD exists between the pairs of the six htSNPs within ERCC2. These results suggested that the risk subhaplotypes cosegregate with one or more biologically functional polymorphisms. Our results provide evidence to support a role for ERCC2 in lung cancer development in a Chinese population.

Background Altered DNA repair capacity due to polymorphisms in DNA repair genes may modify response to Bacillus Calmette–Guerin (BCG) immunotherapy for high risk superficial bladder cancer (SBC).We evaluated the prospective outcome of exicision repair cross complementing group 2 (ERCC2) and apurinic/apyriminidic endonuclease (APEX1) gene in tumor recurrence after BCG immunotherapy in SBC patients. Materials and methods The study included 135 SBC patients, of which BCG immunotherapy was received by 74 patients. Genotyping was performed for ERCC2 Asp312Asn (G > A), Lys751Gln (A > C), and APEX1 Asp148Glu (T > G) polymorphisms by restriction fragment length polymorphism PCR and amplification refractory mutation system (ARMS) methods. Results Multiple Cox regression analysis demonstrated association of variant genotype of ERCC2312AA polymorphism with high risk of recurrence in BCG treated patients (HR = 3.07, P = 0.016, Pc = 0.048). Patients with the ERCC2312AA polymorphic genotypes showed shorter recurrence free survival (log-rank, P = 0.005; AA/GA + AA = 14/44) who received BCG treatment. Overall, risk of recurrence in bladder cancer was observed with smokers and size of tumors (1–3 cm) (HR = 1.86, P = 0.023 and HR = 3.19, P = 0.031, respectively). Smokers were identified to be at elevated risk in BCG treated patients (HR = 2.84, P = 0.005). No association was observed with the (ERCC2 Lys751Gln and APEX1 Asp148Glu) polymorphisms and risk of recurrence. Conclusion Our data suggested variant (AA) of ERCC2 312 AA genotype to be associated with high risk of tumor recurrence and reduced recurrence free survival in superficial bladder cancer patients.

Summary Sunlight/ultraviolet (UV) irradiation has been recognized as an important risk factor for developing systemic lupus erythematosus (SLE). However, the interpretation of genetic variations involved in UV-light sensitivity is largely unknown. Recent studies indicated that two genetic variations of ERCC2/XPD gene (rs1799793 in exon 10 and rs13181 in exon 23) have been found to exert negative influences on nucleotide excision repair system. To analyse the possible contribution of the ERCC2/XPD functional single nucleotide polymorphisms in genetic susceptibility to SLE, the rs13181 and rs1799793 SNPs in ERCC2/XPD were genotyped by polymerase chain reaction followed by restriction fragment length polymorphism analysis. Association was studied by case–control analyses using samples from 172 SLE patients and 160 healthy controls. Haplotype analysis was performed to detect the association with genetic predisposition to SLE and the clinical features. Although these two functional genetic variations are linked to several immune dysfunction-induced diseases, no statistically significant differences in allele or genotype frequencies were observed between SLE patients and controls. Haplotype analysis showed that none of ERCC2/XPD haplotypes was associated with the incidence of SLE disease, nor the preference of clinical features. In conclusion, the ERCC2/XPD functional polymorphisms analysed in this study showed no association in genetic susceptibility to SLE.

Patients with xeroderma pigmentosum (XP) have a 1,000-fold increase in ultraviolet (UV)-induced skin cancers while trichothiodystrophy (TTD) patients, despite mutations in the same genes, ERCC2 (XPD) or ERCC3 (XPB), are cancer-free. Unlike XP cells, TTD cells have a nearly normal rate of removal of UV-induced 6-4 photoproducts (6-4PP) in their DNA and low levels of the basal transcription factor, TFIIH. We examined seven XP, TTD, and XP/TTD complex patients and identified mutations in the XPD gene. We discovered large differences in nucleotide excision repair (NER) protein recruitment to sites of localized UV damage in TTD cells compared to XP or normal cells. XPC protein was rapidly localized in all cells. XPC was redistributed in TTD, and normal cells by 3 hr postirradiation, but remained localized in XP cells at 24-hr postirradiation. In XP cells recruitment of other NER proteins (XPB, XPD, XPG, XPA, and XPF) was also delayed and persisted at 24 hr (p < 0.001). In TTD cells with defects in the XPD, XPB, or GTF2H5 (TTDA) genes, in contrast, recruitment of these NER proteins was reduced compared to normals at early time points (p < 0.001) and remained low at 24 hr postirradiation. These data indicate that in XP persistence of NER proteins at sites of unrepaired DNA damage is associated with greatly increased skin cancer risk possibly by blockage of translesion DNA synthesis. In contrast, in TTD, low levels of unstable TFIIH proteins do not accumulate at sites of unrepaired photoproducts and may permit normal translesion DNA synthesis without increased skin cancer.

Arsenic (As) has been shown to alter one or more DNA repair processes. Excision repair cross-complementing 1 and 2 (ERCC1 and ERCC2) have shown to be associated with arsenic-induced toxicity and carcinogenicity. In this study, we investigated cytotoxic effects of various As metabolites in relation to two nucleotide excision repair genes: ERCC1 and ERCC2. Various arsenate (pentavalent) and arsenite (trivalent) metabolites were tested in ERCC1, ERCC2 deficient and wild type cells. Our results showed that in the selected concentration range pentavalent As metabolites; iAs(V), MMA(V) and DMA(V) were not cytotoxic, unlike the trivalent As metabolites; iAs(III), MMA(III) and DMA(III). The measured LC(50) demonstrated a significant difference (p0.01) for iAs(III) between the three cell lines, while MMA(III) and DMA(III) are more cytotoxic to all three cell lines. UV5 (ERCC2 deficient) cells also showed a lower resistance to iAs(III) in comparison to AA8 (wild type) and UV20 (ERCC2 deficient) cells. This might be explained through the generation of hydrogen peroxide (H(2)O(2)), which is generated by increase of intracellular Ca(2+) level. Generation of H(2)O(2) in UV5 cells after incubation with iAs(III) is significantly higher than AA8 and UV20 cells (p0.01). In conclusion, absence of ERCC2 leads to a increased generation of H(2)O(2) by iAs(III) in UV5 cells, which is in contrast to AA8 and UV20 cells.

Benzo[a]pyrene diol epoxide (BPDE)-induced DNA adducts are a risk factor for tobacco-related cancers. Excision repair cross-complementing complementation group 1 (ERCC1) and excision repair cross-complementing complementation group 2/xeroderma pigmentosum D (ERCC2/XPD) participate in the nucleotide excision repair (NER) pathway that removes BPDE-DNA adducts; however, few studies have provided population-based evidence for this association. Therefore, we assayed for levels of in vitro BPDE-induced DNA adducts and genotypes of single-nucleotide polymorphisms (SNPs) of the NER genes ERCC1 (rs3212986 and rs11615) and ERCC2/XPD (rs13181, rs1799793 and rs238406) in 707 healthy non-Hispanic whites. The linear trend test of increased adduct values in never to former to current smokers was statistically significant (P trend = 0.0107). The median DNA adduct levels for the ERCC2 rsl799793 GG, GA and AA genotypes were 23, 29 and 30, respectively ( P trend = 0.057), but this trend was not observed for other SNPs. After adjustment for covariates, adduct values larger than the median value were significantly associated with the genotypes ERCC1 rs3212986TT [odds ratio (OR) = 1.89, 95% confidence interval (CI) = 1.03-3.48] and ERCC2/XPD rs238406AA (OR = 0.64, 95% CI = 0.41-0.99) and rs238406CA (OR = 0.63, 95% CI = 0.45-0.89) compared with their corresponding wild-type homozygous genotypes. The results of haplotype analysis further suggested that haplotypes CAC and CGA of ERCC2/XPD, TC of ERCC1 and CACTC of ERCC2/XPD and ERCC1 were significantly associated with high levels of DNA adducts compared with their most common haplotypes. Our findings suggest that the genotypes and haplotypes of ERCC1 and ERCC2/XPD may have an effect on in vitro BPDE-induced DNA adduct levels.

Tobacco smoking, alcohol drinking, and occupational exposures to polycyclic aromatic hydrocarbons are the major proven risk factors for human head and neck squamous-cell cancer (HNSCC). Major research focus on gene-environment interactions concerning HNSCC has been on genes encoding enzymes of metabolism for tobacco smoke constituents and repair enzymes. To investigate the role of genetically determined individual predispositions in enzymes of xenobiotic metabolism and in repair enzymes under the exogenous risk factor tobacco smoke in the carcinogenesis of HNSCC, we conducted a case-control study on 312 cases and 300 noncancer controls. We focused on the impact of 22 sequence variations in CYP1A1, CYP1B1, CYP2E1, ERCC2/XPD, GSTM1, GSTP1, GSTT1, NAT2, NQO1, and XRCC1. To assess relevant main and interactive effects of polymorphic genes on the susceptibility to HNSCC we used statistical models such as logic regression and a Bayesian version of logic regression. In subgroup analysis of nonsmokers, main effects in ERCC2 (Lys751Gln) C/C genotype and combined ERCC2 (Arg156Arg) C/A and A/A genotypes were predominant. When stratifying for smokers, the data revealed main effects on combined CYP1B1 (Leu432Val) C/G and G/G genotypes, followed by CYP1B1 (Leu432Val) G/G genotype and CYP2E1 (-70G>T) G/T genotype. When fitting logistic regression models including relevant main effects and interactions in smokers, we found relevant associations of CYP1B1 (Leu432Val) C/G genotype and CYP2E1 (-70G>T) G/T genotype (OR, 10.84; 95% CI, 1.64-71.53) as well as CYP1B1 (Leu432Val) G/G genotype and GSTM1 null/null genotype (OR, 11.79; 95% CI, 2.18-63.77) with HNSCC. The findings underline the relevance of genotypes of polymorphic CYP1B1 combined with exposures to tobacco smoke.

Background and objective: Expression of genes involved in DNA repair and/or DNA synthesis, including ribonucleotide reductase M1 (RRM1) and excision repair cross-complementation 1 (ERCC1) has been reported to be associated with chemosensitivity to platinum agents and gemcitabine. The aim of this study was to test whether similar associations would be seen between mRNA expression for the RRM1, ERCC1 and ERCC2 genes and in vitro chemosensitivity in lung cancer. Methods: Using a panel of 20 lung cancer cell lines, including 15 NSCLC and 5 small cell lung cancers (SCLC), the mRNA expression levels for the RRM1, ERCC1 and ERCC2 genes were examined by quantitative real-time reverse transcription PCR. The in vitro cytotoxicity of cisplatin, carboplatin and gemcitabine was assessed using a tetrazolium-based colorimetric assay (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazoliumbromide (MTT) assay). Results: Significantly, higher RRM1 mRNA expression was found in SCLC compared with NSCLC. However, there were no correlations between mRNA expression of the ERCC1, ERCC2 and RRM1 genes and chemosensitivity to cisplatin, carboplatin or gemcitabine. Conclusions: These in vitro results suggest that further studies are needed to evaluate the expression of the RRM1, ERCC1 and ERCC2 genes as predictive biomarkers for sensitivity to platinum agents and gemcitabine.

DNA repair systems enable our cells to respond to carcinogens and mutagens. The ERCC2 gene encodes a DNA repair protein that has multiple regulatory cellular functions including nucleotide excision repair, basal transcription, cell cycle control, and apoptosis. The ERCC2 polymorphism Lys751Gln may alter the capacity for DNA repair, which could affect the risk of certain cancers. We examined whether the Lys751Gln polymorphism was associated with the risk of breast cancer in Chinese women by analysing the genotype frequencies in 486 patients with breast cancer and 479 cancer-free control subjects. At least one variant allele (Lys/Gln or Gln/Gln) was associated with a 44% decreased risk of breast cancer. Patients with breast cancer with the 751Lys/Gln or 751Gln/Gln genotypes were less likely to be hormone receptor positive. In conclusion, our results demonstrated that ERCC2 polymorphisms might be potential risk markers for breast cancer in the Chinese population.

To evaluate the joint effect of nine single nucleotide polymorphisms for three DNA repair genes in the region of chromosome 19q13.2-3 on susceptibility of lung cancer in a Chinese population, we conducted a hospital-based case–control study consisting of 247 lung cancer cases and 253 cancer-free controls matched on age, gender and ethnicity. Associations between the haplotypes and susceptibility of lung cancer were tested. The global test of haplotype association revealed a statistically significant difference in the haplotype distribution between cases and controls (global test: χ 2 = 60.45, d.f. = 15, P = 2.11E−07). The two haplotypes were underrepresented among cases (Hap5 defined by ERCC1 118 A – ERCC2 156 C – ERCC2 312 G – ERCC2 751 A – XRCC1 194 T – XRCC1 206 A – XRCC1 280 G – XRCC1 399 G – XRCC1 632 G and Hap12 defined by ERCC1 118 G – ERCC2 156 C – ERCC2 312 G – ERCC2 751 A – XRCC1 194 C – XRCC1 206 A – XRCC1 280 G – XRCC1 399 A – XRCC1 632 G ). Three of the haplotypes were overrepresented among cases (Hap3 defined by ERCC1 118 A – ERCC2 156 C – ERCC2 312 G – ERCC2 751 A – XRCC1 194 C – XRCC1 206 A – XRCC1 280 G – XRCC1 399 G – XRCC1 632 G , Hap4 defined by ERCC1 118 A – ERCC2 156 C – ERCC2 312 G – ERCC2 751 A – XRCC1 194 C – XRCC1 206 G – XRCC1 280 G – XRCC1 399 G – XRCC1 632 A , and Hap10 defined by ERCC1 118 G – ERCC2 156 A – ERCC2 312 G – ERCC2 751 A – XRCC1 194 T – XRCC1 206 A – XRCC1 280 G – XRCC1 399 G – XRCC1 632 G ). Haplotypes 3 and 10 (cases = 5.7%, controls = 1.0%, OR = 6.56, 95%CI = 1.83–23.54, P = 0.001; cases = 13.3%, controls = 5.6%, OR = 2.73, 95%CI = 1.51–4.94, P = 0.0006) were the most strongly associated with increased lung cancer risk. There was considerable linkage disequilibrium exists between SNPs both within genes and between genes in the region. The two blocks for solid spine of LD and six htSNPs were found. The haplotype analysis suggested that the biologically effective polymorphisms co-segregate with some of the haplotypes. This result supports the hypothesis that the sub-region is important for lung cancer susceptibility. Haplotype studies using larger study groups will be required to obtain conclusive results.

To evaluate the associations of breast cancer risk with polymorphisms in the XPC and XPD/ERCC2 DNA nucleotide excision repair genes, a case-control study nested within a prospective cohort of 14,274 women was conducted. Genotypes were characterized for 612 incident, invasive breast cancer cases and their 1:1 matched controls. The homozygous variant of a poly(AT) insertion/deletion polymorphism in intron 9 of the XPC gene (XPC-PAT+/+), was associated with breast cancer risk [odds ratio (OR) = 1.45, 95% confidence interval: 1.07-1.97], after adjustment for other breast cancer risk factors. The breast cancer risk associated with XPC-PAT+/+ did not differ by age at diagnosis. There was an indication of an interaction (p = 0.08) between the XPC-PAT+/+ genotype and cigarette smoking. Ever smokers with the XPC-PAT+/+ genotype were at elevated risk of breast cancer (OR = 1.56, CI: 0.95-2.58), but no differences were observed among never smokers. Analyses of the ERCC2 Lys751Gln polymorphism did not show an association with breast cancer risk, either overall or at younger ages. The results suggest that breast cancer risk is related to the XPC haplotype tagged by the XPC-PAT+/+ insertion-deletion polymorphism in intron 9. Further study of the XPC haplotypes and their interactions with smoking in relation to breast cancer risk is needed.

The present study was conducted in a Chinese population to evaluate the usefulness and sensitivity of PAH-DNA adduct as a biomarker of PAH exposure, and to examine the potential effects of smoking and polymorphisms of responsive genes on DNA adduct formation induced by PAH exposure. The polymorphisms of genes examined include GSTM1, GSTT1, CYP1A1, microsomal epoxide hydrolase (mEH) and excision repair cross-complementary group 2 (ERCC2). A total of 194 subjects with a broad range of PAH exposures were recruited, including 116 occupationally exposed workers, 49 metropolitan residents and 29 suburban gardeners. A significant exposure-response relationship was observed between PAH exposure and DNA adducts in leukocytes across the entire group of subjects (p0.0001). The levels of PAH-DNA adducts in the subgroup with lowest occupational exposure to PAHs (0.1 microg BaP m(-3)) was significantly higher than that in metropolitan residents and suburban gardeners. However, no significant difference was detected between residents and gardeners, with mean BaP concentrations of 0.028 and 0.011 microg m(-3), respectively. The polymorphisms of genes examined failed to show significant effects on PAH-induced adduct formation except ERCC2 Lys751Gln genotypes. A significantly higher level of PAH-DNA adduct was found in subjects with wild-type ERCC2 than those who have either heterozygous or homozygous variant alleles (p0.01). Smoking, age and gender did not substantially contribute to PAH-induced DNA adduct formation in this study. The study suggests that PAH-DNA adducts may serve as a reliable biomarker of PAH exposure in occupational settings but may not be sensitive enough to be used in populations with environmental exposures to PAHs.

Epidemiological studies documented associations between single nucleotide polymorphisms (SNPs) in the nucleotide excision repair gene XPD/ERCC2 and cancer risk. Little is known, however, about the underlying mechanisms for these associations. We explored a novel mechanism that could further explain the reported risk-modifying effect of these SNPs on disease susceptibility.Using quantitative real-time polymerase chain reaction, we examined the relationship between three SNPs in the XPD gene (R156R in exon 6, D312N in exon 10 and K751Q in exon 23) and mRNA levels as a potential mechanism by which these SNPs could alter DNA repair capacity and affect disease risk. To further investigate the mechanism(s) by which these SNPs alter mRNA transcription levels, we performed a localized Mfold structure analysis on the mRNA sequence surrounding the studied SNPs.All three SNPs studied, alone and in combination, significantly decreased constitutive XPD mRNA levels (P0.003) in lymphocytes of healthy subjects. The decrease in mRNA levels was significantly greater in smokers and was exacerbated by smoking duration and intensity. The decrease was more pronounced in older than in younger subjects. The R156R and the K751Q polymorphisms were predicted to alter mRNA secondary structure, indicating that these SNPs potentially affect local folding and mRNA stability.Our results provide novel mechanistic explanations for epidemiological studies linking these SNPs to elevated cancer risk and emphasize the importance of comprehensively investigating the effect of both synonymous and nonsynonymous SNPs as risk modifiers by considering their potential effects on gene expression, protein translation and functions.

Excision repair cross-complimentary group 2 (ERCC2) is one of the important DNA repair genes. ERCC2 codon 751 polymorphism has been shown to modulate cancer risk. We therefore assessed the relationship between the ERCC2 polymorphism and the susceptibility to lung cancer in nonsmoking females via a hospital-based case-control study. There were 105 lung cancer cases and matched healthy controls in this study. Information concerning demographic and risk factors was obtained, each person donated 2 ml blood for biomarker testing. ERCC2 genotypes were determined by PCR-RFLP method. All of the statistical analyses were performed with SPSS (v 12.0). All of the subjects in this study were nonsmoking females in Shenyang. There was significant difference between the frequencies of ERCC2 polymorphism in cancer cases and controls (P

The excision repair cross-complementing group 2 (ERCC2) gene encodes a DNA repair protein, which is absolutely necessary in nucleotide excision repair. A polymorphism in codon 751 that induces a Lys-Gln substitution has been suggested to reduce the DNA repair capacity. Therefore, we conducted a matched case-control study to investigate the role ERCC2 Lys751Gln polymorphism in the development of lung cancer in the Chinese population. The genotype of ERCC2 gene was analyzed by di-allele-specific-amplification with artificially modified primers (diASA-AMP) in 200 original lung cancer cases and 200 controls. The results showed that carriers of Lys/Gln and Gln/Gln genotypes had a 3.32-fold higher risk of lung cancer compared with carriers of Lys/Lys genotype. Furthermore, the mutant genotype of 751 Gln allele was found to be associated with an increased risk in both lung squamous cell carcinoma and lung adenocarcinoma. However, no significant interaction between 751Gln variants and smoking was observe...

In the context of a molecular epidemiology study dealing with the effects of individual genetic susceptibility on childhood respiratory morbidity, DNA repair genotypes for the XPD/ERCC2 gene in exon 6 (Arg156Arg) and exon 23 (Lys751Gln) have been analyzed by PCR/RFLP assays in DNA samples isolated from the fetal parts of placentas. The study was performed using a cohort of 729 children born in 1994–1998 in two districts of the Czech Republic. On the basis of these data, we tested the association between the two genotypes. The principal finding of this study is that the exon 6 and exon 23 polymorphisms in the XPD/ERCC2 gene are tightly associated, with persons who are homozygous CC in exon 23 being mostly (81%) homozygous CC in exon 6, and persons homozygous AA in exon 6 mostly (88%) homozygous AA in exon 23. This strong association may have serious consequences for the interpretation of cancer susceptibility and other molecular epidemiology studies dealing with the XPD6 and XPD23 genotypes, since the observed effects of the silent XPD6 polymorphism might be, in fact, the result of XPD23 polymorphism, which is connected with an amino acid substitution in the resulting XPD protein.

The associations between several genetic polymorphisms of nucleotide excision repair genes (NER) and chromosome damage level were studied among 140 coke-oven workers exposed to a high level of polyaromatic hydrocarbons (PAHs) and 66 non-exposed workers. Seven polymorphisms with functional potential in five NER genes (ERCC1, ERCC2, ERCC4, ERCC5 and ERCC6) were genotyped in the 206 study subjects. Multivariate analysis of covariance revealed that coke-oven workers with the ERCC1 19007 CC genotype had significantly higher cytokinesis-block micronucleus frequency (CBMN) (10.5 +/- 6.8 per thousand) than those with CT (8.1 +/- 6.6 per thousand, p = 0.01) or TT (6.6 +/- 3.7-/ per thousand p = 0.05) or CT+TT genotypes (7.5 +/- 6.3 per thousand, p = 0.004). The ERCC6 A3368G polymorphism was also associated with CBMN frequency among coke-oven workers. Subjects with the AA genotype have a significantly higher CBMN frequency (10.0 +/- 6.9 per thousand) than those with AG (6.7 +/- 4.2 per thousand, p = 0.05) or AG+GG genotypes (6.6 +/- 4.1 per thousand, p = 0.02). Stratification analysis revealed the significant associations between ERCC1 C19007T and ERCC6 A3368G, and the CBMN frequencies were only found among older workers. In addition, a significant association between ERCC2 G23591A polymorphism and CBMN frequencies was also found among older coke-oven workers. The results suggest that polymorphisms of ERCC1 C19007T, ERCC6 A3368G and ERCC2 G23591A are associated with the CBMN frequencies among coke-oven workers.

Various DNA alterations can be caused by exposure to environmental and endogenous carcinogens. Most of these alterations, if not repaired, can result in genetic instability, mutagenesis and cell death. DNA repair mechanisms are important for maintaining DNA integrity and preventing carcinogenesis. Recent lung cancer studies have focused on identifying the effects of single nucleotide polymorphisms (SNPs) in candidate genes, among which DNA repair genes are increasingly being studied. Genetic variations in DNA repair genes are thought to modulate DNA repair capacity and are suggested to be related to lung cancer risk. We identified a sufficient number of epidemiologic studies on lung cancer to conduct a meta-analysis for genetic polymorphisms in nucleotide excision repair pathway genes, focusing on xeroderma pigmentosum group A (XPA), excision repair cross complementing group 1 (ERCC1), ERCC2/XPD, ERCC4/XPF and ERCC5/XPG. We found an increased risk of lung cancer among subjects carrying the ERCC2 751Gln/Gln genotype (odds ratio (OR) = 1.30, 95% confidence interval (CI) = 1.14 - 1.49). We found a protective effect of the XPA 23G/G genotype (OR = 0.75, 95% CI = 0.59 - 0.95). Considering the data available, it can be conjectured that if there is any risk association between a single SNP and lung cancer, the risk fluctuation will probably be minimal. Advances in the identification of new polymorphisms and in high-throughput genotyping techniques will facilitate the analysis of multiple genes in multiple DNA repair pathways. Therefore, it is likely that the defining feature of future epidemiologic studies will be the simultaneous analysis of large samples.

The disease Xeroderma Pigmentosum (XP) is genetically heterogeneous and defined by pathogenic variants (formerly termed mutations) in any of eight different genes. Pathogenic variants in the XPC gene are the most commonly observed in US patients. Moreover, pathogenic variants in just four of the genes, XPA, XPC, XPD/ERCC2 and XPV/POLH account for 91% of all XP cases worldwide. In the current study, we describe the clinical, histopathologic, molecular genetic, and pathophysiological features of a 19-year-old female patient clinically diagnosed with XP as an infant. Analysis of archival material reveals a novel variation of a 13 base pair deletion in XPC exon 14 and a previously reported A>C missense pathogenic variant in the proximal splice site for XPC exon 6. Both variations induce frameshifts most likely leading to a truncated XPC protein product. Quantitative RT-PCR also revealed reduced mRNA levels in the archived specimen. Analysis of the XPA, XPD/ERCC2 and XPV/POLH genes in the current specimen failed to reveal pathologic variants. All previously reported pathogenic variants, polymorphisms and known amino acid changes for the XPC gene are compiled and described in the current nomenclature. Given the relative ease of screening for genetic variation and the potential role for such variation in human disease, a proposal for screening appropriate archival materials for alterations in the four most prevalent XP genes is presented.

Background The relationship between ERCC2 polymorphisms and the risk of radiotoxicity remains inconclusive. The aim of our study is to systematically evaluate the association between ERCC2 polymorphisms and the risk of radiotoxicity. Methods Publications were identified through a search of the PubMed and Web of Science databases up to August 15, 2015. The pooled odds ratios (ORs) with corresponding 95 % confidence intervals (CIs) were calculated to evaluate the association between ERCC2 polymorphisms and radiotoxicity. Trial sequential analysis (TSA) and power calculation were performed to evaluate the type 1 and type 2 errors. Results Eleven studies involving 2584 patients were ultimately included in this meta-analysis. Conventional meta-analysis identified a significant association between ERCC2 rs13181 polymorphism and radiotoxicity (OR = 0.71, 95 % CI: 0.55-0.93, P = 0.01), but this association failed to get the confirmation of TSA. Conclusions The minor allele of rs13181 polymorphism may confer a protect effect against radiotoxicity. To confirm this correlation at the level of OR = 0.71, an overall information size of approximate 2800 patients were needed. Electronic supplementary material The online version of this article (doi:10.1186/s13014-015-0558-6) contains supplementary material, which is available to authorized users.

Genetic variants found in DNA repair genes (ERCC1, rs3212986; ERCC2, rs13181; ERCC4, rs1800067; ERCC5, rs17655; XRCC1, rs1799782, rs25487, rs25489; XRCC3, rs861539) have been reported to have an ambivalent association with the development of glioma. In the present study, a meta-analysis was conducted to confirm the relationship, taking heterogeneity of population into consideration. We analyzed 21 articles of 6 genes along with 8 single nucleotide polymorphisms (SNPs) (24,078 cases and 30,926 healthy individuals), which assessed the relationship between nucleotide excision, base excision, double-strand break repair gene, and the development of glioma under five models. All statistical analysis was implemented by the software of R 3.2.1, and the relationships between key polymorphic loci in DNA repair genes and glioma were quantified by the pooled odds ratio (OR) and 95 % confidential intervals. Overall, the synthesized evidence demonstrated that the SNP of rs13181 and rs1799782 significantly increased the risk of glioma whereas SNP of rs1800067 were significantly associated with a decrease in the risk of glioma. Additionally, subgroup analyses of 8 SNPs by ethnicity indicated that the mutation of rs13181, rs1800067 were apparently protective factors of glioma among Asians, while the mutation of rs13181 was a risk factors of glioma in Caucasians. Furthermore, the mutation of rs1799782 significantly raises the risk of glioma for Asian. Our study suggested that rs13181*C and rs1799782*A are risk alleles for glioma; rs1800067*A are beneficial alleles for decreased susceptibility to glioma. Future studies with large sample size and other races are strongly recommended to confirm the results from this study.