Common Gene Polymorphisms Research Articles

Genetic polymorphisms as determinants of pesticide toxicity: Recent advances.

Occupational and environmental exposure to pesticides may induce harmful effects on human health by promoting the development of a wide range of disorders. Some of the most recently hypothesized mechanisms are oxidative stress and epigenetic modifications, however biological effects seem to be modulated mainly by the occurrence of genetic polymorphisms. The susceptibility to exposure can be evaluated by studying the most common polymorphisms of genes involved in the metabolism of organophosphorus compounds (cytochrome P450, glutathione transferase, acetyltransferases or paraoxonase 1). The aim of this article is to review recent literature data concerning the influence of genetic polymorphisms on pesticides-induced oxidative damage.

No clinical utility of common polymorphisms in IGF1, IRS1, GCKR, PPARG, GCK1 and KCTD1 genes previously associated with insulin resistance in overweight children from Romania and Moldova.

Background Previous genome-wide association studies (GWAS) identified IGF1, IRS1, GCKR, PPARG, GCK1 and KCTD1 as candidate genes for insulin resistance and type 2 diabetes (T2D). We investigated the associations of these previously reported common variants in these genes with insulin resistance in overweight children from Romania and Moldova. Methods Six single nucleotide polymorphisms (SNPs), IGF1 (rs35767), IRS1 (rs2943634), GCKR (rs780094), PPARG (rs1801282), GCK1 (rs1799884) and KCTD15 (rs29941), were genotyped in 100 overweight children along with clinical and metabolic parameters. Homeostatic model assessment of insulin resistance (HOMA-IR) above 3.4 (defining insulin resistance) was used as the outcome. Results Children differed in insulin resistance status despite having similar body mass index (BMI) standard deviation scores (SDS) (World Health Organization, [WHO] reference). The identified predictors for altered insulin metabolism were higher cholesterol levels, higher diastolic blood pressure and higher waist-to-hip-ratio (as a marker for increased abdominal fat). None of the SNPs showed significant association with increase in the risk for insulin resistance in children (p range=0.478-0.724; odds ratio [OR] range=1.924-4.842); however, the risk allele in GCKR (rs780094, p=0.06, OR=6.871) demonstrated near statistical significance. Conclusions The interrogated risk alleles did not show any significant association with insulin resistance in children in our cohort; however, the GCKR (rs780094) might be a viable candidate in larger cohorts. The lack of replication of the proposed association may point to differences in linkage disequilibrium or effect modifiers across studies.

The genetic association between osteoprotegerin (OPG) gene polymorphisms and bone mineral density (BMD) in postmenopausal women

Osteoporosis is a common skeletal disorder in eldest people, especially in postmenopausal women. The osteoprotegerin (OPG) gene has been reported to be associated with the BMD and pathogenesis of osteoporosis. However, the results were inconsistent and inconclusive in previous studies. A meta-analysis was performed to investigate the effect of four common OPG gene polymorphisms (A163G, G1181C, T245G, and T950C) on BMD in postmenopausal women. A total of 23 eligible studies with 12,973 postmenopausal women were enrolled in present study. Individuals who with AA genotype of A163G were found to have slightly higher femoral hip (P = .03, SMD = 0.49, [95% CI] = [0.06, 0.91]) and total hip BMD (P = .002, SMD = -0.25, [95% CI] = [-0.42, -0.09]) than those with AG genotype. Subjects with GG genotype of G1181C was found to have lower BMD than those with CC or GC genotypes in lumbar spine (GG vs GC: P = .0002, SMD = -0.85, [95% CI] = [-1.29, -0.41]; GG vs CC: P = .02, SMD = -0.21, [-0.39, -0.03]) and total hip BMD (GG vs GC: P = .002, SMD = -0.25, [95% CI] = [-0.42, -0.09]; GG vs CC: P = .01, SMD = -0.15, [95% CI] = [-0.26, -0.03]). In addition, the subjects with GC genotype of G1181C was detected to have lower BMD than those with CC genotype in lumbar spine BMD (P < .05). Furthermore, individuals with TT genotype of T950C were shown to have significant lower lumbar spine BMD compared with those with genotype CC in Caucasian (P < .05). The lumbar spine BMD was lower for subjects with TC genotype of T950C than those with CC genotype in both Caucasian and Asian populations (P < .05). In contrast to A163G, G1181C, and T950G, no association was detected between T245G polymorphism and BMD (P > .05). The present meta-analysis demonstrated the OPG A163G, G1181C, and T950G, but not T245G, might influence the BMD in postmenopausal women.

A long-lived IL-2 mutein that selectively activates and expands regulatory T cells as a therapy for autoimmune disease

Susceptibility to multiple autoimmune diseases is associated with common gene polymorphisms influencing IL-2 signaling and Treg function, making Treg-specific expansion by IL-2 a compelling therapeutic approach to treatment. As an in vivo IL-2 half-life enhancer we used a non-targeted, effector-function-silent human IgG1 as a fusion protein. An IL-2 mutein (N88D) with reduced binding to the intermediate affinity IL-2Rβγ receptor was engineered with a stoichiometry of two IL-2N88D molecules per IgG, i.e. IgG-(IL-2N88D)2. The reduced affinity of IgG-(IL-2N88D)2 for the IL-2Rβγ receptor resulted in a Treg-selective molecule in human whole blood pSTAT5 assays. Treatment of cynomolgus monkeys with single low doses of IgG-(IL-2N88D)2 induced sustained preferential activation of Tregs accompanied by a corresponding 10–14-fold increase in CD4+ and CD8+ CD25+FOXP3+ Tregs; conditions that had no effect on CD4+ or CD8+ memory effector T cells. The expanded cynomolgus Tregs had demethylated FOXP3 and CTLA4 epigenetic signatures characteristic of functionally suppressive cells. Humanized mice had similar selective in vivo responses; IgG-(IL-2N88D)2 increased Tregs while wild-type IgG-IL-2 increased NK cells in addition to Tregs. The expanded human Tregs had demethylated FOXP3 and CTLA4 signatures and were immunosuppressive. These results describe a next-generation immunotherapy using a long-lived and Treg-selective IL-2 that activates and expands functional Tregsin vivo. Patients should benefit from restored immune homeostasis in a personalized fashion to the extent that their autoimmune disease condition dictates opening up the possibility for remissions and cures.

The microbiome of translocated bacterial populations in patients with and without inflammatory bowel disease.

Using culture-based methods, bacterial translocation from the gut to draining mesenteric lymph nodes is seen in 5% of normal controls and up to 33% of patients with inflammatory bowel diseases (IBD). Many bacteria cannot be cultured, so these methods are unable to capture the full spectrum of bacteria present. To detect viable bacteria in lymph nodes of patients with IBD and non-IBD controls using bacterial RNA as a surrogate for viability and to compare them with the same patient's gut microbiome. Bacterial RNA was extracted from lymph nodes and mucosa of 20 patients who had undergone intestinal resection (10 IBD, 10 non-IBD). A previous study had detected bacterial DNA in these patients' lymph nodes; 16S rRNA gene high-throughput sequencing was performed. Bacterial RNA was detected in the lymph nodes of five patients with IBD and three controls (volvulus, diverticulitis and bowel obstruction). Lymph nodes had higher alpha (within sample) diversity compared to mucosal samples (Shannon diversity index 2.41 vs 1.81, one-way ANOVA P = 0.035). Beta diversity (inter-sample variation: lymph node vs intestine) was similar within individuals and did not differ between groups. Common gene polymorphisms linked with IBD (NOD2, ATG16L1, IRGM and IL23R) were not associated with bacterial translocation. Metabolically active bacteria mirroring the individual's gut microbiome were commonly found in the lymph nodes of patients with IBD undergoing resection. An increase in lymph node alpha diversity is likely due to the larger drainage area. The presence of viable bacteria in non-IBD controls is also not unexpected given the underlying pathology in these patients.

Genetic variability and population diversity of the human SLCO (OATP) transporter family.

Organic anion transporting polypeptides (OATP) encoded by the SLCO gene family constitute clinically important transporters involved in the disposition of endogenous compounds and many commonly prescribed drugs, including statins, methotrexate and antihypertensive medications. Common genetic polymorphisms in SLCO genes are known to affect OATP function and modulate efficacy and safety of OATP substrates. However, current frequency data of these variants and haplotypes is generally based on few rather heterogenous populations of relatively small sample size. Furthermore, the genetic variability beyond these selected pharmacogenetic biomarkers has not been systematically analyzed. Here, we provide a global consolidated map of SLCO variability by leveraging fully compatible Next Generation Sequencing data from 138,632 unrelated individuals across seven major human populations. Overall, we find 9811 exonic single nucleotide variants and 155 copy number variations of which 99.3% were rare with frequencies <1%. Using orthogonal computational functionality predictors optimized for pharmacogenetic assessments, we find that four out of five individuals carry at least one deleterious variant in an SLCO transporter gene and rare variants contribute 23% to the genetically encoded functional variability. Moreover, 74.9% of all variants were found to be population-specific with important consequences for population-specific genotyping strategies and precision public health approaches. Combined, our analyses provide the most comprehensive data set of SLCO variability published to date and incentivize the integration of comprehensive NGS-based genotyping into personalized predictions of OATP substrate disposition.

Association of DAT1 genetic variants with habitual sleep duration in the UK Biobank.

Short sleep duration has been linked to negative health effects, but is a complex phenotype with many contributing factors, including genetic. We evaluated 27 common single nucleotide polymorphisms (SNPs) in candidate genes previously reported to be associated with other sleep variables for association with self-reported habitual sleep duration in the UK Biobank in 111 975 individuals of European ancestry. Genetic variation in DAT1 (rs464049) was significantly associated with sleep duration after correction for multiple testing (p = 4.00 × 10-5), whereas SNPs correlated to a previously studied variable number tandem repeat (VNTR) in DAT1 were not significant in this population. We also replicated a previously reported association in DRD2. Independent replication of these associations and a second signal in DRD2 (rs11214607) was observed in an additional 261 870 participants of European ancestry from the UK Biobank. Meta-analysis confirmed genome-wide significant association of DAT1 rs464049 (G, beta [standard error, SE] = -0.96 [0.18] minutes/allele, p = 5.71 × 10-10) and study-wide significant association of DRD2 (rs17601612, C, beta [SE] = -0.66 [0.18] minutes/allele, p = 1.77 × 10-5; rs11214607, C, beta [SE] = 1.08 (0.24) minutes/allele, p = 1.39 × 10-6). Overall, SNPs in two dopamine-related genes were significantly associated with sleep duration, highlighting the important link of the dopamine system with adult sleep duration in humans.

Influence of polymorphisms in VEGF, ACE, TNF and GST genes on the susceptibility to retinopathy of prematurity among Chinese infants.

To investigate common polymorphisms in VEGF, ACE, TNF and GST genes with retinopathy of prematurity (ROP) risk among Chinese infants. Nine polymorphisms in the above genes were genotyped on 724 advanced cases of ROP and 878 prematurely-born infants of low birth weight who were without any ophthalmologic disease. The frequencies of the polymorphisms were compared between cases and controls to identify the association present, if any. Of the nine polymorphisms, only two showed significant associations: ACE insertion deletion (ID) polymorphism (P=0.031) and TNF -308G/A polymorphism (P<0.001). The former was associated with a reduced ROP risk [ID genotype, adjusted OR (aOR): 0.603, 95%CI: 0.427-0.893, P=0.034; DD genotype, aOR: 0.468, 95%CI: 0.229-0.626, P=0.002], while the latter showed an increased risk (GA genotype, aOR: 1.956, 95%CI: 1.396-2.465, P<0.001; AA genotype, aOR: 2.809, 95%CI: 1.802-4.484, P<0.001). The association was also noted at the allele level (ACE D allele aOR: 0.698, 95%CI: 0.294-0.883, P<0.001; TNF -308A allele aOR: 1.776, 95%CI: 1.446-2.561, P<0.001). The ACE ID polymorphism can protect against ROP development while the TNF -308G/A can increase the risk of the disease among Chinese infants.

The relationship between MTHFR polymorphisms and abortion in Iranian women

BackgroundRecurrent spontaneous abortion (RSA) is a significant obstetrical complication during pregnancy. Two common polymorphisms (C677T and A1298C) of the methylenetetrahydrofolate reductase (MTHFR) gene are risk factors for RSA. This study was performed to determine the effect of C677T and A1298C polymorphisms in RSA. The true relationship between these two mutations and risk of recurrent spontaneous abortion is unknown, and it is unclear if women with these mutations should be given anticoagulants during pregnancy. Materials and methodsIn this prospective and experimental study, one hundred and fifty three individuals were referred with clinical findings that included recurrent spontaneous abortions minimum of 2 and maximum of 5. Total genomic DNA was isolated from peripheral blood samples. To determine the frequency of the two common C677T and A1298C MTHFR gene polymorphisms in the patients, we used PCR-restriction fragment length polymorphism method. ResultsThe frequency of Heterozygous and homozygous C677T polymorphisms were 18.13% and 13.1% respectively. The frequency of Heterozygous and homozygous A1298C polymorphisms were 18.3% and 15.7% respectively. The frequency of Heterozygous C677T and A1298C polymorphisms were 26.8% and wild-type individuals were 7.8%. All female subjects who had heterozygous or homozygous C677T and A1298C polymorphisms with recurrent RSA were followed and those who received appropriate anti-coagulant therapy resulted in successful pregnancy. ConclusionIn present study, we provided witness to support the relationship between MTHFR C677T and A1298C polymorphisms and recurrent spontaneous abortion. Also, we suggest that anticoagulation therapy of these patients during pregnancy could lead to a successful pregnancy outcome.

The Relationship of the TLR9 and TLR2 Genetic Polymorphisms with Cervical Cancer Risk: a Meta-Analysis of Case-Control Studies.

This meta-analysis aimed to assess the association of common TLR9 and TLR2 gene polymorphisms (TLR9 1486T/C, TLR9 G2848A, and TLR2-196 to -174 del/ins) with cervical cancer risk. Studies were searched in Scopus, Pubmed, Embase, and CNKI until December 2017. Both fixed-effects and random-effects models were applied to combine odds ratio (OR) and 95% confidence intervals (95% CI). A total of 11 studies including 7856 participants were identified. The pooled estimation revealed an increased risk of cervical cancer in Caucasian subjects carrying the C allele of the TLR9 1486T/C polymorphism (OR = 1.46, 95% CI: 1.11-1.92, p = 0.007), while there was a decreased risk in Mixed subjects carrying the C allele (OR = 0.35, 95% CI: 0.15-0.82, p = 0.016). Concerning the TLR9 G2848A polymorphism, the A allele was associated with an increased risk of cervical cancer in Caucasians (OR = 1.19, 95% CI: 1.02-1.40, p = 0.030), whereas Asian and Mixed subjects showed no significant associations. No significant associations were demonstrated between the TLR2-196 to -174 del/ins polymorphism and cervical cancer. Our findings suggest that the TLR9 1486T/C and G2848A polymorphisms contribute to cervical cancer risk, but there is no association of the TLR2-196 to -174 del/ins polymorphism with cervical cancer.

Functional monoamine oxidase B gene intron 13 polymorphism predicts putaminal dopamine turnover in de novo Parkinson's disease.

The objective of this study was to evaluate the effects of common functional polymorphisms in genes involved in dopamine metabolism on striatal dopamine turnover in de novo Parkinson's disease (PD). This was an observer-blinded cohort study investigating effects of common functional polymorphisms in dopa decarboxylase (DDC, rs921451), monoamine oxidase B (MAOB; rs1799836), catechol-O-methyltransferase (COMT, rs4680), and dopamine transporter/solute carrier family 6 member 3 (DAT/SLC6A3, variable number tandem repeats) genes on 18 F-fluorodopa uptake and an effective distribution volume ratio (inverse of dopamine turnover) measured by 18 F-fluorodopa PET in 28 untreated PD patients. Patients carrying the MAOBCC/(C)/CT genotype (low/intermediate enzyme activity) had a lower dopamine turnover in the putamen (higher mean effective distribution volume ratio) when compared with patients with MAOBTT/(T) genotype (high enzyme activity). Striatal PET measures were not different between variants in the remaining genes. The MAOB (rs1799836) polymorphism predicts putaminal dopamine turnover in early PD with the MAOBTT allele linked to high enzyme activity leading to higher intrinsic dopamine turnover, which has been demonstrated to constitute a risk factor for motor complications. © 2018 The Authors. Movement Disorders published by Wiley Periodicals, Inc. on behalf of International Parkinson and Movement Disorder Society.

Maternal dietary antioxidant intake in pregnancy and childhood respiratory and atopic outcomes: birth cohort study

Evidence for a possible protective effect of maternal dietary antioxidant intake during pregnancy on childhood asthma and other atopic outcomes is conflicting, and associations with childhood lung function have been little studied.In the Avon Longitudinal Study of Parents and Children, we analysed associations between maternal intake of fruits, vegetables, vitamins C and E, carotene, zinc, and selenium in pregnancy and current doctor-diagnosed asthma, atopy and lung function in 8915 children at age 7–9 years. Potential modification of associations by maternal smoking and common maternal antioxidant gene polymorphisms was explored to strengthen causal inference.After controlling for confounders, positive associations were observed between maternal intake of zinc and childhood forced expiratory volume in 1 s and forced vital capacity (difference in age-, height- and sex-adjusted sd units per quartile increase in maternal dietary zinc intake β 0.05 (95% CI 0.01–0.08); ptrend=0.01 and 0.05 (95% CI 0.02–0.09); ptrend=0.005, respectively). Weak evidence was found for an interaction between maternal zinc intake and maternal glutathione S-transferase GSTM1 genotype on childhood forced vital capacity (pinteraction=0.05); association among the GSTM1 null group β 0.11 (95% CI 0.05–0.17); ptrend=0.001.Our results suggest that a higher maternal intake of zinc during pregnancy may be associated with better lung function in the offspring.

Postprandial lipemia and its relation to TCF7L2 gene polymorphisms in normoglycemic first-degree relatives of type 2 diabetes patients

We compared postprandial triglyceride (PPTg) responses to fat challenge between risk allele and wild-type variant of two common TCF7L2 gene polymorphisms to ascertain if the risk of T2DM associated with this gene is related to its effects on PPTg metabolism. Postprandial triglyceride levels were evaluated in 71 NGT subjects with at least one first-degree relative with T2DM. Restriction fragment length polymorphism was performed for genotyping of SNP rs7903146 C/T and SNP rs12255372 G/T of TCF7L2 gene, and the PPTg levels were compared in the risk allele and wild-type variant of both these SNPs. Postprandial triglyceride responses were similar in wild and risk allele groups for both the SNPs. There was no significant difference in Tg-AUC (2027.04 ± 1313.54 vs 1853.58 ± 712.00, p = 0.472) and Peak Tg levels (343.95 ± 225.08 mg/dl vs 320.60 ± 137.49 mg/dl, p = 0.591) between CC and CT + TT of SNP rs7903146. Also, no significant difference was observed between Tg-AUC (1936.41 ± 1120.77 vs 1891.38 ± 812.69, p = 0.845) and peak Tg levels (324.89 ± 186.99 mg/dl vs 330.42 ± 158.64 mg/dl, p = 0.894) between GG and GT + TT of SNP rs12255372. The present study did not find any significant difference in PPTg responses between the risk allele and wild type of rs7903146(C/T) and rs12255372 (G/T) SNPs of TCF7L2 gene.

Investigation of C1-complex regions reveals new C1Q variants associated with protection from systemic lupus erythematosus, and affect its transcript abundance

Although rare variant C1Q deficiency was identified as causative risk for systemic lupus erythematosus (SLE), there are limited and inconsistent reports regarding the common polymorphisms of C1Q genes in SLE susceptibility. Furthermore, there are no reports concerning polymorphisms of C1S, C1R, and C1RL and whether they confer susceptibility to SLE. We therefore evaluated 22 SNPs across six C1-complex genes in two independent case-control cohorts, and identified four novel SNPs that confer protection from SLE. The four SNPs are all located in C1Q. Particularly, the variant rs653286 displayed an independent reduced risk on SLE susceptibility (OR 0.75, P = 2.16 × 10−3) and anti-dsDNA antibodies (OR 0.68, P = 0.024). By bioinformatics analysis, SNPs rs653286 and rs291985 displayed striking cis-eQTL effects on C1Q genes expression. Individuals homozygous for the ‘protective’ allele at four SNPs had significantly higher levels of serum C1q (rs680123–rs682658: P = 0.0022; rs653286–rs291985: P = 0.0076). To our knowledge, this is the first study to demonstrate that only C1Q polymorphisms are associated with SLE. The C1Q SNP rs653286 confers an independent protective effect on SLE susceptibility and affects transcript abundance.

Gene variants in the NF-KB pathway (NFKB1, NFKBIA, NFKBIZ) and their association with type 2 diabetes and impaired renal function

The NF-kappaB pathway might play a role in the pathogenesis of renal disease and type 2 diabetes (T2DM). Our aim was to determine whether common polymorphisms in NF-kappaB genes were associated with impaired renal function and T2DM in a cohort of healthy elderly individuals. We studied 487 individuals, all Caucasian and aged 65–85 years. A total of 104 (21%) had impaired renal function (estimated glomerular filtration rate, eGFR < 60) and 146 (30%) were classified as diabetics. The genotypes of 4 common variants were determined through PCR-RFLP or fluorescent capillary electrophoresis.The NFKB1 variants were significantly associated with T2DM: rs7667496 p = 0.01, OR = 1.68; and rs28362491 p = 0.02, OR = 1.67. They remained significantly associated in a multiple logistic regression with age, gender, hypertension, body mass index, and cholesterol. There was a trend toward the association of these variants with eGFR < 60. The two NFKB1 variants were in linkage disequilibrium (D′ = −0.86), and homozygous for the two non-risk alleles (rs7667496 CC + rs28362491 II), were significantly more common in the non-diabetics (p = 0.02).In our cohort the NFKB1 variation was an independent risk factor for developing T2DM. Additional studies to confirm this association are of special interest, as well as studies to give a functional explanation to the genetic association.

Gene-gene interactions among coding genes of iron-homeostasis proteins and APOE-alleles in cognitive impairment diseases

Cognitive impairments of different aetiology share alterations in iron and lipid homeostasis with mutual relationships. Since iron and cholesterol accumulation impact on neurodegenerative disease, the associated gene variants are appealing candidate targets for risk and disease progression assessment. In this light, we explored the role of common single nucleotide polymorphisms (SNPs) in the main iron homeostasis genes and in the main lipoprotein transporter gene (APOE) in a cohort of 765 patients with dementia of different origin: Alzheimer’s disease (AD) n = 276; vascular dementia (VaD), n = 255; mild cognitive impairment (MCI), n = 234; and in normal controls (n = 1086). In details, four genes of iron homeostasis (Hemochromatosis (HFE: C282Y, H63D), Ferroportin (FPN1: -8CG), Hepcidin (HAMP: -582AG), Transferrin (TF: P570S)), and the three major alleles of APOE (APOE2, APOE3, APOE4) were analyzed to explore causative interactions and synergies. In single analysis, HFE 282Y allele yielded a 3-fold risk reduction in the whole cohort of patients (P<0.0001), confirmed in AD and VaD, reaching a 5-fold risk reduction in MCI (P = 0.0019). The other iron SNPs slightly associated with risk reduction whereas APOE4 allele resulted in increased risk, reaching more than 7-fold increased risk in AD homozygotes (P = 0.001), confirmed to a lower extent in VaD and MCI (P = 0.038 and P = 0.013 respectively) as well as in the whole group (P<0.0001). Comparisons of Mini Mental State Examination (MMSE) among AD showed appreciable lowering in APOE4 carriers (P = 0.038), confirmed in the whole cohort of patients (P = 0.018). In interaction analysis, the HFE 282Y allele completely extinguished the APOE4 allele associated risk. Conversely, the coexistence in patients of a substantial number of iron SNPs accrued the APOE4 detrimental effect on MMSE. Overall, the analysis highlighted how a specific iron-allele burden, defined as different combinations of iron gene variants, might have different effects on cognitive impairment and might modulate the effects of established genetic risk factors such as APOE4. Our results suggest that established genetic risk factors might be affected by specific genetic backgrounds, making patients differently suited to manage iron accumulation adding new genetic insights in neurodegeneration. The recently recognized interconnections between iron and lipids, suggest that these pathways might share more than expected. We therefore extended to additional iron gene variants the newly proposed influencing mechanisms that HFE gene has on cholesterol metabolism. Our results have a strong translational potential promoting new pharmacogenetics studies on therapeutic target identification aimed at optimally tuning brain iron levels.

PTGS2 polymorphism rs689466 favors breast cancer recurrence in obese patients.

Breast cancer is the leading cancer among women, and its increasing incidence is a challenge worldwide. Estrogen exposure is the main risk factor, but obesity among postmenopausal women has been shown to favor disease onset and progression. The link between obesity and mammary carcinogenesis involves elevated estrogen production and proinflammatory stimuli within the adipose tissue, with activation of the cyclooxygenase-2 pathway. Here, we evaluate the impact of the four most common cyclooxygenase-2 gene polymorphisms (rs689465, rs689466, rs20417 and rs20417), in combination with obesity, on the risk of breast cancer progression in a cohort of Brazilian breast cancer patients (N = 1038). Disease-free survival was evaluated using Kaplan-Meier curves, with multivariate Cox proportional hazards regression models for calculation of adjusted hazard ratios (HRadj). Obesity did not affect disease progression, whereas rs689466 variant genotypes increased the recurrence risk among obese patients (HRadj = 2.5; 95% CI = 1.4-4.3), either for luminal (HRadj = 2.2; 95% CI = 1.1-4.2) or HER2-like and triple-negative tumors (HRadj = 3.2; 95% CI = 1.2-8.5). Likewise, the haplotype *4, which contains variant rs689466, was associated with shorter disease-free survival among obese patients (HRadj = 3.3; 95% CI = 1.8-6.0), either in luminal (HRadj = 3.5; 95% CI = 1.6-7.3) or HER2-like and triple-negative (HRadj = 3.1; 95% CI = 1.1-8.9) tumors. Such deleterious impact of variant rs689466 on disease-free survival of obese breast cancer patients was restricted to postmenopausal women. In conclusion, cyclooxygenase-2 genotyping may add to the prognostic evaluation of obese breast cancer patients.

GSTP1 Ile105Val polymorphism might be associated with the risk of radiation pneumonitis among lung cancer patients in Chinese population: A prospective study.

Background: Growing data suggest that DNA damage repair and detoxification pathways play crucial roles in radiation-induced toxicities. To determine whether common functional single-nucleotide polymorphisms (SNPs) in candidate genes from these pathways can be used as predictors of radiation pneumonitis (RP), we conducted a prospective study to evaluate the associations between functional SNPs and risk of RP.Methods: We recruited a total of 149 lung cancer patients who had received intensity modulated radiation therapy (IMRT). GSTP1 and XRCC1 were genotyped using the SurPlexTM-xTAG method in all patients. RP events were prospectively scored using the National Cancer Institute Common Terminology Criteria for Adverse Events (CTCAE), version 4.0. Kaplan-Meier analysis was used to determine the cumulative probability of RP of grade ≥ 2. Cox proportional hazard regression was performed to identify clinical variables and SNPs associated with risk of RP grade ≥ 2, using univariate and multivariate analysis, respectively.Results: With a median follow-up of 9 months, the incidence of RP of grade ≥ 2 was 38.3%. A predicting role in RP was observed for the GSTP1 SNP (adjusted hazard ratio 3.543; 95% CI 1.770-7.092; adjusted P< 0.001 for the Ile/Val and Val/Val genotypes versus Ile/Ile genotype). Whereas, we found that patients with XRCC1 399Arg/Gln and Gln/Gln genotypes had a lower risk of RP compares with those carrying Arg/Arg genotype (adjusted HR 0.653; 95% CI 0.342-1.245), but with no statistical significance observed (adjusted P = 0.195).Conclusions: Our results suggested a novel association between GSTP1 SNP 105Ile/Val and risk of RP development, which suggests the potential use of this genetic polymorphism as a predictor of RP. In addition, genetic polymorphisms of XRCC1 399Arg/Gln may also be associated with RP.

Coagulation factor VII gene polymorphisms are not associated with the occurrence or the survival of hepatocellular carcinoma: a report of 37 cases.

Objective: Coagulation factor VII (FVII) triggers the extrinsic pathway of blood coagulation. In our previous study, we showed that FVII plays an important role in tumorigenesis of hepatocellular carcinoma (HCC). However, the role of FVII polymorphism in HCC is still unknown. The present study aimed to investigate the relationship between HCC carcinogenesis and single nucleotide polymorphism of FVII.Methods: Thirty-seven HCC patients and 30 healthy donors were recruited in this study. Four common FVII gene polymorphisms – a decanucleotide insertion at position –323 (–323ins10-bp), a G to T substitution at position –401 (–401G/T), a G to A substitution at position –402 (–402G/A), and a T to C substitution at position –122 (–122T/C) – were analyzed by sequencing or commercialized assays using genomic DNA isolated from blood samples. Clinicopathological parameters between control and HCC subjects were compared according to the specific genotypes.Results: The most common nucleotide variation was –402G/A. However, no statistically significant difference was observed between healthy controls and HCC subjects for all four polymorphisms in terms of genotype distribution and allele frequencies, indicating that these polymorphisms may not affect HCC tumorigenesis. Furthermore, no association was found between –402G/A polymorphisms and tumor stage, recurrence, and overall survival.Conclusions: Our results indicate that FVII polymorphisms may not be a key factor that clinically impact tumorigenesis and outcomes of HCC, although further investigations should be conducted to confirm our findings.

Study of the relation between two common cyclooxygenase 2 gene polymorphisms with risk of developing and subtypes of vitiligo in Egyptian patients

Genetic factors play an important role in the pathogenesis of vitiligo. Cyclooxygenase 2 (COX2) gene induced by ultraviolet radiation controls the synthesis of prostaglandins, which are are found to be beneficial in treating vitiligo. COX2 gene polymorphism has been previously evaluated in Chinese population. We aimed to study the relation between two common COX2 gene polymorphisms with vitiligo and its subtypes amongEgyptian patients. This study included 200 participants (100 vitiligo patients and 100 healthy controls). COX2-765G/C and -1195A/G gene polymorphism was studied by restriction fragment length polymorphism polymerase chain reaction analysis and the results were compared between the two groups and among different subtypes of vitiligo. Frequency of COX2-1195 AA, AG, GG genotypes showed no significant association among patients with vitiligo (P = 0.626, 0.321, 0.08, respectively); those with generalized vitiligo (P = 0.739, 0.291, 0.101, respectively) and those with segmental vitiligo (P = 0.410, 1.00, 0.676, respectively) compared to the control group. Regarding COX2-765G/C genotypes, GG genotype was more frequent among patients with vitiligo [84 (84%)] compared to controls [63 (63%)] (P = 0.001). GC genotype was significantly less frequent [15 (15%)] among patients compared to controls [32 (32%)] (P = 0.005). Generalized and segmental types of vitiligo also showed no significant difference in the frequency of COX2-765G/C genotypes compared with controls. Being a pilot study, a relatively small number of participants were included. COX2-1195A/G gene polymorphism is not associated with the risk of developing vitiligo or with vitiligo subtypes. COX2-765 GG genotype is associated with vitiligo, especially of the generalized type.