Investigated Gene Polymorphisms Research Articles

Theory of Mind: A Brief Review of Candidate Genes.

Deficits in theory of mind (ToM), known as the ability to understand the other's mind, have been associated with several psychopathological outcomes. The present systematic review aims to summarize the results of genetic studies that investigated gene polymorphisms associated with mentalization performance tasks in children and adults. The systematic review was carried out following PRISMA guidelines, and the literature search was conducted in PubMed and EBSCOhost using the following keywords: 'theory of mind, mentalizing, mindreading' and 'gene, genetic basis'. Nineteen studies met the eligibility criteria for inclusion. Most of the literature focused on the role of DRD4, DAT1, OXTR, OXT, COMT, ZNF804A, AVP, AVPR, SCL6A4, EFHC2, MAO-A, and the family of GTF2I genes in influencing ToM. However, controversial results emerged in sustaining the link between specific genetic polymorphisms and mentalization abilities in children and adults. Available data show heterogeneous outcomes, with studies reporting an association between the same family genes in subjects of the same age and other studies reporting no correlation. This does not allow us to draw any solid conclusions but paves the way for exploring genes involved in ToM tasks.

Polymorphism of tmprss2 (rs12329760) but not ace2 (rs4240157), tmprss11a (rs353163) and cd147 (rs8259) is associated with the severity of COVID-19 in the Ukrainian population.

Angiotensin-converting enzyme 2 (ACE2), transmembrane serine 2 and serine 11A proteases (TMPRSS2, TMPRSS11A), and a cell surface cluster of differentiation 147 (CD147) might be a gene candidate that exerts the susceptibility to and mortality from coronavirus disease 19 (COVID-19). The aim of this study was to investigate the associations between ace2, tmprss2, tmprss11a, and cd147 polymorphic variants and the severity of COVID-19 in the Ukrainian population. The study population consisted of the Ukrainian population with COVID-19: patients without oxygen therapy (n=62), with non-invasive (n=92) and invasive (n=35) oxygen therapy, as well as control subjects (n=92). Allelic polymorphisms of ace2 rs4240157, tmprss2 rs12329760, and tmprss11a rs353163 were determined by real-time PCR, and cd147 rs8259 polymorphism was detected by PCR with subsequent restrictase analysis. We compared investigated polymorphisms distribution with other populations by meta-analysis. Our study is the first to obtain data about the distribution of investigated gene polymorphisms in the Ukrainian population: tmprss2 rs12329760 - CC 60.9%, CT 35.9%, TT 3.2%; tmprss11a rs353163 - CC 46.7%, CT 40.2%, TT 13.1%; ace2 rs4240157 - CC 7.6%, C 18.5%, CT 22.8%, TT 19.6%, T 31.5%; cd147 rs8259 - TT 60.9%, AT 32.6%, AA 6.5%. This distribution was similar to the Northern, Western and Southern European populations. There was a statistically significant difference in the frequency of tmprss2 polymorphic genotypes CC 57.1%, CT 28.6%, and TT 14.3% (P<0.05) in COVID-19 patients with invasive oxygen therapy in comparison with non-invasive oxygen therapy. This tmprss2 mutation occurs in the scavenger receptor cysteine-rich (SRCR) domain and might be important for protein-protein interaction in a calcium-dependent manner. Our study indicated the presence of an association between the tmprss2 rs12329760 polymorphism and the severity of COVID-19 in the Ukrainian population.

Association between a single nucleotide polymorphism in the R3HCC1 gene and irinotecan toxicity.

Irinotecan is a useful anticancer drug for colorectal cancer treatment. UGT1A1*28 and *6 gene polymorphisms are known risk factors for irinotecan-associated toxicity. However, severe adverse effects due to irinotecan have been observed even in patients who do not harbor UGT1A1*28 or *6. We investigated gene polymorphisms in the whole exome to identify useful biomarkers for irinotecan toxicity other than UGT1A. A total of 178 patients with metastatic colorectal cancer (mCRC) and 87 patients with pancreatic cancer were treated with FOLFIRI, FOLFOX, FOLFOXIRI, modified FOLFIRINOX, or gemcitabine plus nab-paclitaxel. Genome-wide screening was performed using whole-exome sequencing (WES), and validation analysis was performed using qPCR with a hydrolysis probe. Using WES after a doublet chemotherapy regimen comprising irinotecan and 5-fluorouracil (n=15), seven single nucleotide polymorphisms (SNPs) were identified as candidate biomarkers for irinotecan-associated toxicity of neutropenia. Among the seven SNPs, an SNP in R3H domain and coiled-coil containing 1 (R3HCC1; c.919G > A, rs2272761) showed a significant association with neutropenia (>grade 3) after doublet chemotherapy. Patients receiving irinotecan including triplet chemotherapy, FOLFOXIRI for mCRC (n=23) or modified FOLFIRINOX for pancreatic cancer (n=40), also showed significant linear trends between R3HCC1 polymorphism and neutropenia (p=0.017 and 0.046, respectively). No significant association was observed in patients treated with irinotecan-free regimens, FOLFOX for mCRC (n=66), and gemcitabine plus nab-paclitaxel for pancreatic cancer (n=47). Thus, an SNP in the R3HCC1 gene may be a useful biomarker for the toxicity of irinotecan-containing chemotherapy for mCRC and pancreatic cancer.

The Association of Polymorphisms in Genes Encoding Antioxidant Enzymes GPX1 (rs1050450), SOD2 (rs4880) and Transcriptional Factor Nrf2 (rs6721961) with the Risk and Development of Prostate Cancer.

Background and Objectives: Mounting evidence implicates oxidative damage in prostate carcinogenesis, contributing to modifications of macromolecules that drive cellular malignant transformation. Functional single-nucleotide polymorphisms (SNPs) of enzymes involved in redox homeostasis can disrupt pro-oxidant–antioxidant balance, leading to accumulation of reactive oxygen species and oxidative damage. We investigated the potential role of genetic polymorphisms of antioxidant enzymes glutathione peroxidase 1 (GPX1 rs1050450) and superoxide dismutase 2 (SOD2 rs4880) and regulatory antioxidant protein nuclear factor erythroid 2-related factor 2 (Nrf2 rs6721961) in the susceptibility to prostate cancer development (PC) and prognosis. Materials and Methods: We conducted a case–control study consisting of 235 patients with PC and 240 controls. Gene polymorphisms were determined by quantitative polymerase chain reaction (qPCR) and polymerase chain reaction with confronting two-pair primers (PCR-CTTP) methods. Multiple risk models were composed to inspect the separate and mutual effect of multiple genes and in combination with acquired contributory factors on the risk of PC development. Results: Independently, carriers of at least one SOD2*C allele had increased risk of PC development, which was significantly further amplified in advanced statistical models. When tested in combination, individuals with both SOD2*C allele and Nrf2*C/C genotype were also at increased risk of PC development, which was augmented when combined with acquired contributory factors. During the mean 75 ± 25 months of follow-up, investigated gene polymorphisms did not affect overall survival. Conclusion: Our results suggest that these gene polymorphisms could be used as risk biomarkers of PC evolution.

Single-nucleotide polymorphisms of the SLC17A9 and P2RY12 genes are significantly associated with phantom tooth pain.

Phantom tooth pain (PTP) is a rare and specific neuropathic pain that occurs after pulpectomy and tooth extraction, but its cause is not understood. We hypothesized that there is a genetic contribution to PTP. We focused on solute carrier family 17 member 9 (SLC17A9)/vesicular nucleotide transporter (VNUT) and purinergic receptor P2Y12 (P2RY12), both of which have been associated with neuropathic pain and pain transduction signaling in the trigeminal ganglion in rodents. We sought to corroborate these associations in humans. We investigated gene polymorphisms that contribute to PTP. We statistically examined the association between genetic polymorphisms and PTP vulnerability in 150 patients with orofacial pain, including PTP, and 500 healthy subjects. We found that the rs735055 polymorphism of the SLC17A9 gene and rs3732759 polymorphism of the P2RY12 gene were associated with the development of PTP. Carriers of the minor allele of rs735055 and individuals who were homozygous for the major allele of rs3732759 had a higher rate of PTP. Carriers of the minor allele of rs735055 reportedly had high SLC17A9 mRNA expression in the spinal cord, which may increase the storage and release of adenosine triphosphate. Individuals who were homozygous for the major allele of rs3732759 may have higher P2RY12 expression that is more active in microglia. Therefore, these carriers may be more susceptible to PTP. These results suggest that specific genetic polymorphisms of the SLC17A9 and P2RY12 genes are involved in PTP. This is the first report on genes that are associated with PTP in humans.

Polymorphisms of genes encoding drug transporters or cytochrome P450 enzymes and association with clinical response in cancer patients: a systematic review.

Not all patients respond well to cancer chemotherapy. One of the most important factors contributing to treatment response (efficacy and toxicity) is genetic determinant. The current systematic review aims to provide current status of the information on the genetic contribution of genes encoding drug transport proteins and drug metabolizing enzyme, cytochrome P450 (CYP), and relationship with clinical outcomes of cancer chemotherapy. The literature search was performed through PubMed and ScienceDirect databases. One hundred and four research articles that fulfilled the inclusion criteria and had none of the exclusion criteria were included in the analysis. Various studies reported conflicting results for the polymorphisms of the major genes and association with treatment outcomes in patients with various types of cancer. Nevertheless, among the investigated gene polymorphisms, it appears that the 1236C>T, 3435C>T and 2677 G>T/A SNPs of the drug transporter gene ABCB1 were the most promising determinants of clinical outcomes. Although both 1236C>T and 3435C>T polymorphism are synonymous SNPs, several studies have demonstrated that not all synonymous SNPs are silent. Therefore, using the haplotype (1236C>T, 2677G>T, and 3435C>T) analysis rather than a single SNP may be a more useful approach for phenotype prediction. Some of the patients with variants of CYP genes were associated with unsatisfactory treatment response (efficacy and toxicity), suggesting that these variants may be associated with either reduction or absence of CYP enzyme activity. The controversial results may be due to several factors including difference in populations studied, sample size, tumor sites and stages, chemotherapeutic drug regimens, and evaluation parameters for efficacy and/or toxicity. Before the information can be successfully applied to individualized cancer chemotherapy, further studies should be focused on these promising genetic markers and their association with clinical outcomes using standardized protocols.

S115. SYMPTOM DOMAINS IN SCHIZOPHRENIA AND GENE POLYMORPHISMS

BackgroundDopamine and serotonin neurotransmission relies mostly on the action of four factors: serotonin and dopamine transporters (SERT and DAT) and enzymes monoaminooxidase A (MAO-A) and catechol-O-mehtyltransferase (COMT). The goal of this research was to closely examine schizophrenia symptom domains in relation to the investigated polymorphisms.MethodsStudy group was composed of 300 schizophrenic patients. Severity of schizophrenia was assessed by the Positive and negative syndrome scale (PANSS), depressive symptoms were assessed with Calgary depression scale for schizophrenia (CDSS). SERT (5-HTTLPR), DAT (VNTR), COMT (Val158Met) and MAO-A (VNTR) gene polymorphisms were analyzed. Schizophrenia symptom dimensions were determined with multivariate statistical methods, while logistic regression and ANOVA were used to investigate the influence of a genotype on a symptom domain.ResultsFactor analysis of PANSS scale retained all 30 items and identified 5 separate factors (aggressive/impulsive, affective/depressive, cognitive, negative and positive symptoms). Analysis of CDSS scale revealed 2 separate factors (depression and suicidality).Statistically significant PANSS variables were those of aggressive/impulsive and negative symptoms, while suicidality was the only significant CDSS variable.DiscussionOur PANSS scale factor analysis established 5 distinct factors. Previous factor analyses provided from 3, up to 7 different factors, but mostly 5 distinct ones: negative symptoms, positive symptoms, depressive symptoms, excitement and disorganization. That factor distribution corresponds to our findings in terms of identified number of factors, but seems to differ in terms of item distribution within those factors.When testing the influence of investigated gene polymorphisms on the variable of total PANSS score and five distinct factors we did not establish significant findings regarding four variables: total PANSS score, positive, cognitive and affective/depressive symptoms. While that is in line with majority of other investigations, SERT promoter polymorphism and COMT Val158Met gene polymorphism have been previously associated with depressive and positive symptoms. SERT and MAO-A polymorphisms separately had a significant effect on the variable of aggressive/impulsive symptoms, which has not been reported earlier. Furthermore, significant influence of COMT gene polymorphism was established for the variable of negative symptoms, which is a confirmation of some earlier reports, although there have been contrary findings.Previous reports of CDSS scale factor structure are limited to data from its initial validation to the few recent findings of its three-factor structure (depression, cognition and melancholy). We identified 2 separate factors using factor analysis, “depression” (which included seven out of nine items) and “suicidality”. To the best of our knowledge this is the first investigation of the putative association between any of the four investigated polymorphisms and depressive symptoms of schizophrenia measured by the CDSS scale. Ultimately, we did not establish a significant association of investigated gene polymorphisms and total CDSS score, as well as the “depression” factor. However, there was a significant association between the “suicidality” factor and SERT and MAO-A gene polymorphisms, as well as their interaction. The fact that the significant association was established for only one of the two obtained CDSS factors suggests that the association is subtle and, at least partially, explains rarely reported associations between investigated gene polymorphisms and schizophrenia symptom domains, which is especially true for depressive symptomatology.

Depressive symptoms in schizophrenia and dopamine and serotonin gene polymorphisms

Although depressive symptoms seem to be frequent in schizophrenia they have received significantly less attention than other symptom domains. As impaired serotonergic and dopaminergic neurotransmission is implicated in the pathogenesis of depression and schizophrenia this study sought to investigate the putative association between several functional gene polymorphisms (SERT 5-HTTLPR, MAO-A VNTR, COMT Val158Met and DAT VNTR) and schizophrenia. Other objectives of this study were to closely examine schizophrenia symptom domains by performing factor analysis of the two most used instruments in this setting (Positive and negative syndrome scale - PANSS and Calgary depression rating scale - CDSS) and to examine the influence of investigated gene polymorphisms on the schizophrenia symptom domains, focusing on depressive scores. A total of 591 participants were included in the study (300 schizophrenic patients and 291 healthy volunteers). 192 (64%) of schizophrenic patients had significant depressive symptoms. Genotype distribution revealed no significant differences regarding all investigated polymorphisms except the separate gender analysis for MAO-A gene polymorphism which revealed significantly more allele 3 carriers in schizophrenic males. Factor analysis of the PANSS scale revealed the existence of five separate factors (symptom domains), while the CDSS scale revealed two distinct factors. Several investigated gene polymorphisms (mostly SERT and MAO-A, but also COMT) significantly influenced two factors from the PANSS (aggressive/impulsive and negative symptoms) and one from the CDSS scale (suicidality), respectively. Depressive symptoms in schizophrenic patients may be influenced by functional gene polymorphisms, especially those implicated in serotonergic neurotransmission.

APOA5 Gene Polymorphisms and Cardiovascular Diseases: Metaprediction in Global Populations.

Apolipoprotein A5 (APOA5) 1131 is one of the most investigated gene polymorphisms in association with cardiovascular diseases (CVD) for its roles in epigenetics pathways. The major objective of this metaprediction study was to comprehensively examine the association of polymorphism risk subtypes of APOA5 1131 gene and potential contributing factors of CVD risks in global populations. This study is a meta-analysis to determine APOA5 gene polymorphisms as risk factors for CVDs. Following the guidelines of meta-analyses, we applied big data analytics including the recursive partition tree, nonlinear association curve fit, and heat maps for data visualization-in addition to the conventional pooled analyses. A total of 17,692 CVD cases and 23,566 controls from 50 study groups were included. The frequency of APOA5 1131 CC and TC polymorphisms in Asian populations (22.2%-52.6%) were higher than that in other populations, including Caucasians and Eurasians (10.0%-25.0%). The homozygous CC and heterozygous TC genotypes (both p < .0001) were associated with increased risks for CVD and were higher in many Western nations, including Canada, Spain, the Czech Republic, Hungary, Turkey, Egypt, France, and Iran. The CC genotype was associated with greater risks (RR > 2.00, p < .0001) for dyslipidemia and myocardial infarction, whereas RR > 1.00 was associated with metabolic syndrome, coronary artery disease, and stroke. Air pollution was significantly associated with APOA5 1131 CC and TC polymorphisms. The findings of this study provided novel insight to further understand the associations among APOA5 1131 polymorphisms, air pollution, and the development of CVDs. Methylation studies are needed to examine epigenetic factors associated with APOA5 1131 polymorphisms and CVD and to suggest potential prevention strategies for CVD.

Role of cytokine gene polymorphisms in acute and chronic kidney disease following liver transplantation.

Development of renal dysfunction, including acute kidney injury (AKI) and chronic kidney disease (CKD), after liver transplantation (LT) remains a critical issue adversely affecting patient survival in both the short and long term. Previous reports have suggested that inflammatory and antiinflammatory cytokines and their functionally relevant gene polymorphisms may play critical roles in the development of AKI and CKD. However, the involvement of these cytokines and their gene polymorphisms in renal deterioration following LT remains unclear. We examined 62 recipients who underwent LT at Nagoya University between 2004 and 2009 and who had survived for at least 1year. The following gene polymorphisms in recipients were analyzed: tumor necrosis factor-A (TNFA) T-1031C, interleukin-2 (IL2) T-330G, IL10 C-819T, IL13 C-1111T, transforming growth factor-B (TGFB) T29C, and IL4 T-33C. Thirteen patients (21%) developed AKI within 4weeks after LT. Of the investigated gene polymorphisms, the IL4 -33 T/T genotype was significantly associated with higher incidence of AKI compared with the other two genotypes [hazard ratio (HR)=5.48, 95% confidence interval (CI) 1.18-25.52, p=0.03]. On the other hand, 16 patients (26%) had developed CKD at median follow-up of 9.2years after LT. We showed the lack of association between investigated gene polymorphisms in recipients and CKD development. The IL4 -33 T/T genotype might be a risk factor for AKI in LT, and this might contribute to earlier withdrawal of immunosuppressive agents to minimize renal toxicity. In contrast, none of the investigated cytokine gene polymorphisms were associated with CKD.

Metabolism and gene polymorphisms of the folate pathway in Brazilian women with history of recurrent abortion.

To investigate the association between polymorphisms in genes that encode enzymes involved in folate- and vitamin B12-dependent homocysteine metabolism and recurrent spontaneous abortion (RSA). We investigated the C677T and A1298C polymorphisms of the methylenetetrahydrofalate reductase gene (MTHFR), the A2756G polymorphism of the methionine synthase gene (MS) and the 844ins68 insertion of the cystathionine beta synthetase gene (CBS). The PCR technique followed by RFLP was used to assess the polymorphisms; the serum levels of homocysteine, vitamin B12 and folate were investigated by chemiluminescence. The EPI Info Software version 6.04 was used for statistical analysis. Parametric variables were compared by Student's t-test and nonparametric variables by the Wilcoxon rank sum test. The frequencies of gene polymorphisms in 89 women with a history of idiopathic recurrent miscarriage and 150 controls were 19.1 and 19.6% for the C677T, insertion, 20.8 and 26% for the A1298C insertion, 14.2 and 21.9% for the A2756G insertion, and 16.4 and 18% for the 844ins68 insertion, respectively. There were no significant differences between case and control groups in any of the gene polymorphisms investigated. However, the frequency of the 844ins68 insertion in the CBS gene was higher among women with a history of loss during the third trimester of pregnancy (p=0.003). Serum homocysteine, vitamin B12 and folate levels id not differ between the polymorphisms studied in the case and control groups. However, linear regression analysis showed a dependence of serum folate levels on the maintenance of tHcy levels. The investigated gene polymorphisms and serum homocysteine, vitamin B12 and folate levels were not associated with idiopathic recurrent miscarriage in the present study. Further investigations are needed in order to confirm the role of the CBS 844ins68 insertion in recurrent miscarriage.

Genetic polymorphisms of paraoxonase1 192 and glutathione peroxidase1 197 enzymes in familial Mediterranean fever

Familial Mediterranean fever (FMF) is an autosomal recessive disorder and is the most frequent of the periodic febrile inflammatory syndromes. The pathogenesis of the disease is not completely understood, even though the FMF gene has been identified. Oxidative stress and inflammation may play a role in the pathogenesis of FMF. We investigated gene polymorphisms of the antioxidative enzymes, glutathione peroxidase (GPX) and paraoxonase (PON) in FMF patients, and possible associations with FMF pathogenesis. Sixty FMF patients during an attack-free period and 51 healthy children as the control group were included in our study. PON1 Q/R192 and GPX1 Pro197Leu gene polymorphisms were assayed. Blood urea nitrogen, creatinine and serum lipid profile were also measured. PON1 Q/R192 genotype distribution was 52% QQ, 46% QR and 2% RR in the FMF group and 45% QQ, 45% QR and 10% RR in the control group (P>0.05). GPX1 Pro197Leu genotype distribution was 28% PP, 57% PL, 15% LL in the FMF group and 18% PP, 53% PL, 29% LL in the control group (P>0.05). Blood urea nitrogen, serum creatinine, lipid levels, and the distribution of PON1 Q/R192 and GPX1 Pro197Leu genotypes were similar in the two groups. We conclude that the PON1 Q/R192 and GPX1 Pro197Leu gene polymorphisms are not important risk factors in the development of FMF. However, larger studies are warranted to validate these conclusions.

CAT, GPX1, MnSOD, GSTM1, GSTT1, and GSTP1 genetic polymorphisms in chronic myeloid leukemia: a case-control study.

Oxidative damage at the DNA level may be promoted by high levels of reactive oxygen species (ROS), leading to genomic instability and increased neoplastic risk. Superoxide dismutase (SOD), glutathione peroxidase (GPX), and catalase (CAT) enzymes are implicated in the prevention of DNA damage by ROS. The aim of the study was to investigate the relationships between CAT C262T, GPX1 Pro198Leu, MnSOD Ala16Val, GSTM1, GSTT1, and GSTP1 Ile105Val polymorphisms and the risk of CML. No association was observed between CML and variant genotypes of GPX1, MnSOD, GSTM1, and GSTT1 polymorphisms in any of the investigated cases. Our study suggests that the homozygous variant genotype of the GSTP1 Ile105Val gene polymorphisms may be associated with the risk of developing CML (OR = 2.5; 95% CI = 1.08–5.7; P value = 0.02), while the heterozygous genotype of the CAT C262T polymorphism seems to have a protective effect against CML (OR = 0.59, 95% CI = 0.39–0.89, P value = 0.01). In most cases, no association was found between laboratory parameters and prognostic factors and the variant genotype of investigated gene polymorphisms. We concluded that CAT, GPX, MnSOD, GSTM1, and GSTT1 gene polymorphisms are not associated with the risk of CML. Variant genotype of the GSTP1 Ile105Val gene polymorphisms may contribute to the risk of developing CML.

Cytokine gene polymorphisms in acute cellular rejection following living donor liver transplantation: analysis of 155 donor-recipient pairs.

Despite improvements in immunosuppressive therapy, acute cellular rejection (ACR) remains an important cause of graft loss in patients undergoing liver transplantation. Recently, associations between cytokine gene polymorphisms in recipients and the occurrence of ACR have been reported. However, most studies did not investigate gene polymorphisms in donors or were limited by the number of cases investigated. We examined 155 living donor liver transplantation (LDLT) patients treated at Nagoya University or Kyoto University from 2004 to 2009. The following gene polymorphisms in recipients and donors were analyzed: tumor necrosis factor A (TNF-A) T-1031C, interleukin 2 (IL-2) T-330G, IL-10C-819T, IL-13C-1111T, and transforming growth factor B (TGF-B) T29C. Forty-seven recipients (30.3%) developed early ACR. Of the investigated gene polymorphisms, the IL-13 -1111C/C genotype in recipients was significantly associated with a higher incidence of ACR relative to the other two genotypes (OR=2.64, 95% CI 1.19-5.86, p=0.017), while we showed the lack of association between investigated gene polymorphisms in donors and ACR incidence. The IL-13 -1111C/C genotype in recipients might be a risk factor for ACR in LDLT, and this might contribute to individualized immunosuppression strategies for recipients. On the other hand, the current study showed no associations of cytokine gene polymorphisms in donors with ACR incidence.

Clinical and genetic outcome determinants of Internet‐ and group‐based cognitive behavior therapy for social anxiety disorder

No study has investigated clinical or genetic predictors and moderators of Internet-based cognitive behavior therapy (ICBT) compared with cognitive behavioral group therapy for (CBGT) for SAD. Identification of predictors and moderators is essential to the clinician in deciding which treatment to recommend for whom. We aimed to identify clinical and genetic (5-HTTLPR, COMTval158met, and BDNFval66met) predictors and moderators of ICBT and CBGT. We performed three types of analyses on data from a sample comprising participants (N = 126) who had undergone ICBT or CBGT in a randomized controlled trial. Outcomes were i) end state symptom severity, ii) SAD diagnosis, and iii) clinically significant improvement. The most stable predictors of better treatment response were working full time, having children, less depressive symptoms, higher expectancy of treatment effectiveness, and adhering to treatment. None of the tested gene polymorphisms were associated with treatment outcome. Comorbid general anxiety and depression were moderators meaning that lower levels were associated with a better treatment response in ICBT but not in CBGT. We conclude that demographic factors, symptom burden, adherence, and expectations may play an important role as predictors of treatment outcome. The investigated gene polymorphisms do not appear to make a difference.

Predictive index for the onset of medication overuse headache in migraine patients

Migraine patients are particularly prone to develop medication overuse headache (MOH). However, the risk factors for the transformation of migraine to MOH are still not clear. We investigated gene polymorphisms, personality traits, and characteristics of headache and lifestyle in 47 migraine patients (aged 36.4 ± 10.3) and 22 MOH patients (aged 39.6 ± 9.9) who progressed from migraine and made a scoring system for a predictive index (PI) of the onset of MOH in patients with migraine. By multivariate logistic stepwise regression analysis, type of migraine, regular and sufficient dietary intake, and methylenetetrahydrofolate reductase (MTHFR) C677T (rs1801133) and dopamine D2 receptor (DRD2) C939T (rs6275) polymorphisms were selected as significant factors that contribute independently to the development from migraine to MOH (P < 0.05). The regression coefficients (β) of these four selected factors were approximated and scored. The PI score in MOH patients (7.32 ± 1.60) was significantly higher than that in migraine patients (4.62 ± 1.83, P < 0.001). The proposed scoring system should in the future be the object of larger studies to confirm its validity.

Role of Inflammation-Related Gene Polymorphisms in Patients with Central Retinal Vein Occlusion

Central retinal vein occlusion (CRVO) is a vision-threatening disease, primarily occurring among patients aged more than 60 years. Several risk factors, including arterial hypertension and diabetes mellitus, have been identified. Compression of the central retinal vein by an atherosclerotic retinal artery at the lamina cribrosa also has been implicated in the pathogenesis of the disease. Functional gene polymorphisms of cytokines or chemokines previously shown to affect atherogenesis or hemostasis are potential risk factors for CRVO. The present study investigates a hypothesized association between inflammation-related gene polymorphisms and the presence of CRVO in a relatively large cohort of patients. Case-control study. The study group consisted of 315 patients with CRVO and 335 control subjects. Determination of genotypes was done by 5' exonuclease assay (TaqMan). Genotypes of interleukin (IL)1β -511C>T, IL1 receptor antagonist (IL1RN) 1018T>C, IL4 -584C>T, IL6 -174G>C, IL10 -592C>A, IL18 183A>G, tumor necrosis factor (TNF)-α -308G>A, monocyte chemoattractant protein (MCP)-1/CCL2 -2518A>G, IL8 -251A>T, and RANTES (CCL5) -403G>A polymorphisms. Genotype distributions and allele frequencies of the investigated gene polymorphisms did not significantly differ between both groups (P>0.05). Arterial hypertension, diabetes mellitus, and cigarette smoking were significantly more frequent in patients with CRVO than among control subjects (arterial hypertension: 67.0% vs. 52.2%, P<0.001; diabetes mellitus: 16.8% vs. 6.3%, P<0.001, cigarette smoking: 32.1% vs. 23.6%, P = 0.02). In a logistic regression analysis, the presence of arterial hypertension was associated with an odds ratio (OR) of 1.75 (95% confidence interval [CI], 1.26-2.44) in those with CRVO, whereas an OR of 2.52 (95% CI, 1.46-4.35) was found in those with diabetes mellitus. A history of cigarette smoking was associated with an OR of 1.57 (95% CI, 1.09 - 2.25) for CRVO. Our data suggest that the investigated inflammation-related gene polymorphisms are unlikely major risk factors for CRVO. The author(s) have no proprietary or commercial interest in any materials discussed in this article.

Analysis of GSTM1 and GSTT1 polymorphisms in circulating plasma DNA of lung cancer patients

The concentration of free circulating plasma DNA and the genetic profile of patients suffering from various types of tumors were studied in an effort to increase the understanding of the biomarkers and genetic factors involved in predisposing an individual to lung cancer (LC). The polymorphic inheritance of glutathione S-transferases (GST), which modulate the effects of various genotoxic agents, especially those derived from benzo[a]pyrene, one of the main tobacco carcinogens, has been implicated in both cancer risk and prognostics. We investigated gene polymorphisms in the blood serum of patients previously diagnosed at the Pneumology Division of the Clementino Fraga Filho University Hospital of the Federal University of Rio de Janeiro and in buccal swab samples of exfoliated oral cells obtained from a population of healthy controls. The distribution of GSTM1 and GSTT1 polymorphisms was not significantly different between LC patients and the controls, suggesting that GSTM1 and GSTT1 alone or in combination are not independent risk factors for LC. However, a close relationship between smoking status and LC was clearly demonstrated. The most significant risk for LC concerning tobacco smoking was found in the association of null genotypes for GSTM1 and GSTT1 (P < 0.0001).

Sequential evaluation of thiopurine methyltransferase, inosine triphosphate pyrophosphatase, and HPRT1 genes polymorphisms to explain thiopurines' toxicity and efficacy

To evaluate the polymorphisms of several genes involved in the azathioprine and mercaptopurine metabolism, in an attempt to explain their toxicity and efficacy in Crohn's disease and ulcerative colitis. In 422 consecutive patients (250 with Crohn's disease and 172 with ulcerative colitis) and 245 healthy controls, single nucleotide polymorphisms of thiopurine methyltransferase, inosine triphosphate pyrophosphatase and hypoxanthine phosphoribosyl transferase (HPRT1) genes were related to the occurrence of adverse drug reactions (ADRs) and efficacy of therapy. Seventy-three patients reported 81 episodes of ADRs; 45 patients did not respond to therapy. Frequency of thiopurine methyltransferase risk haplotypes was significantly increased in patients with leucopenia (26% vs. 5.7% in patients without ADRs, and 4% of controls) (P < 0.001); no correlation with other ADRs and efficacy of therapy was found. Conversely, the frequency of inosine triphosphate pyrophosphatase and HPRT1 risk genotypes was not significantly different in patients with ADRs (included leucopenia). Non-responders had an increased frequency of inosine triphosphate pyrophosphatase risk genotypes (P = 0.03). The majority of azathioprine/mercaptopurine-induced ADRs and efficacy of therapy are not explained by the investigated gene polymorphisms. The combined evaluation of all three genes enhanced the correlation with leucopenia (43.5% vs. 23% in controls) (P = 0.008), at the expense of a reduced accuracy (60%).

Genetic Variation associated with Ischemic Heart Failure: A HuGE Review and Meta-Analysis

The ischemic etiology of heart failure is an independent prognostic factor associated with worse long-term outcome. Recent evidence indicates a role for genetic susceptibility to ischemic heart failure. The authors systematically reviewed all known case-control studies that investigated the association between genetic variants and ischemic heart failure. Twenty-two articles, which examined 24 gene polymorphisms, were identified. In 22 polymorphisms, the variant form had a functional effect. Twenty-two polymorphisms were variants of genes involved in the maladaptive neurohormonal activation. Seven polymorphisms (ACE I/D, AGT M235T, ADRA2C Del322-325, ADRB2 Arg16Gly, ADRB2 Gln27Glu, EDN1 Lys198Asn, VEGF G-405C) showed a significant association in individual studies. Five polymorphisms (ACE I/D, ADRB1 Arg389Gly, ADRB2 Arg16Gly, ADRB2 Gln27Glu, TNF G308A) were examined by more than one study, and meta-analyses were performed. The meta-analyses showed no significant sign of heterogeneity. In all settings, there was no significant association, except for polymorphism ADRB2 Arg16Gly under a recessive model (fixed-effects odds ratio = 1.32, 95% confidence interval: 1.05, 1.65). Taking into account that ischemic heart failure is a complex disease with multifactorial etiology, a minor contributing pathogenetic role of the investigated gene polymorphisms cannot be totally excluded. Case-control studies that investigate gene-gene and gene-environment interactions might further elucidate the genetics of ischemic heart failure.