Low-expression Genotype Research Articles

MAOA methylation is associated with impulsive and antisocial behaviour: dependence on allelic variation, family environment and diet.

Congenital absence of monoamine oxidase A (MAO-A) activity predisposes to antisocial impulsive behaviour, and the MAOA uVNTR low-expressing genotype (MAOA-L) together with childhood maltreatment is associated with similar phenotypes in males. A possible explanation of how family environment may lead to such behaviour involves DNA methylation. We have assessed MAOA methylation and impulsive/antisocial behaviour in 121 males from the Estonian Children Personality Behaviour and Health Study. Of the 12 CpG sites measured, methylation levels at the locus designated CpG3 were significantly lower in subjects with antisocial behaviour involving police contact. CpG3 methylation was lower in subjects with alcohol use disorder by age 25, but only in MAOA-H genotype. No correlation between MAOA CpG3 methylation levels and adaptive impulsivity was found at age 15, but in MAOA-L genotype a positive correlation appeared by age 18. By age 25, this positive correlation was no longer observed in subjects with better family relationships but had increased further with experience of adversity within the family. MAOA CpG3 methylation had different developmental dynamics in relation to maladaptive impulsivity. At age 18, a positive correlation was observed in MAOA-L genotype with inferior family relationships and a negative correlation was found in MAOA-H with superior home environment; both of these associations had disappeared by age 25. CpG3 methylation was associated with dietary intake of several micronutrients, most notable was a negative correlation with the intake of zinc, but also with calcium, potassium and vitamin E; a positive correlation was found with intake of phosphorus. In conclusion, MAOA CpG3 methylation is related to both maladaptive and adaptive impulsivity in adolescence in MAOA-L males from adverse home environment. By young adulthood, this relationship with maladaptive impulsivity had disappeared but with adaptive impulsivity strengthened. Thus, MAOA CpG3 methylation may serve as a marker for adaptive developmental neuroplasticity in MAOA-L genotype. The mechanisms involved may include dietary factors.

Analysis of the TSER and G>C variants in the TYMS gene: a high frequency of low expression genotypes predicted in the Mexican population

Background In the TYMS gene promoter, there is a repeat polymorphism (TSER) that affects the expression level of the thymidylate synthetase (TS) enzyme involved in the response to some anticancer drugs. The G>C transversion located in the TSER*3R allele decreases the expression level of the TS enzyme avoiding the upstream stimulatory factor (USF-1) binding site. Despite the biomedical impact of the SNP G>C, only TSER has been reported in most worldwide populations. Thus, we studied both TSER and SNP G>C variants in the Mexican population. Subjects and methods A population sample (n = 156) was genotyped for the TSER and G>C variants by PCR and PCR-RFLPs, respectively, followed by PAGE and silver staining. Results For TSER, the most frequent allele was 2 R (52.56%), as well as the genotype 2 R/3R (42.3%). Comparison with Latin American, European, and American (USA) populations suggest a heterogeneous worldwide distribution (FST-value = 0.01564; p-value = 0.0000). When the G>C variant was included (2RG, 3RG, and 3RC), a high frequency of low expression genotypes was observed: 2RG/2RG, 2RG/3RC, and 3RC/3RC (84.6%). Conclusion The high frequency of genotypes associated with low TS enzyme expression justifies obtaining the TYMS gene variant profile in Mexican patient’s candidates to pharmaceutical treatments like 5’-Fluoracil, methotrexate, and pemetrex.

Maternal serotonin transporter genotype and offsprings' clinical and cognitive measures of ADHD and ASD

Serotonin (5-HT) is an important factor for prenatal neurodevelopment whereby its neurotrophic actions can be regulated through maternal-fetal interactions. We explored if maternal 5-HTTLPR genotype is associated with clinical and cognitive measures of attention-deficit/hyperactivity disorder (ADHD) and comorbid autism spectrum disorder (ASD) in typically-developing and ADHD-diagnosed offspring, beyond classical inheritance and environmental- and comorbidity-mediators/confounders. Family-based variance decomposition analyses were performed incorporating 6–31 year-old offsprings' as well as parental genotypes of 462 ADHD and control families from the NeuroIMAGE cohort. Dependent measures were offsprings' ADHD symptom- and ASD trait-scores and cognitive measures including executive functioning (including response inhibition and cognitive flexibility), sustained attention, reward processing, motor control, and emotion recognition. Offsprings' stereotyped behavior was predicted by an interaction between maternal 5-HTTLPR genotype and offsprings' sex. Furthermore, offspring of mothers with low-expressing genotypes demonstrated larger reward-related reductions in reaction time. While specifically adult male offspring of these mothers reported a faster reversal learning with less errors, specifically young female offspring of these mothers were more accurate in identifying happy faces. Adult offspring from the mothers with low-expressing 5-HTTLPR genotypes were also slower in identifying happy faces. However, this association seemed to be mediated by offsprings' high anxiety levels. In sum, we found some support for a role of the maternal 5-HT system in modulating fetal brain development and behavior. Offsprings' cognitive measures might be more sensitive to small alterations within the maternal 5-HT system than their ADHD and ASD clinical phenotypes. Further studies are needed to specify the association between maternal genotype and risk for neurodevelopmental disorders.

Mannose-binding lectin and risk of infections in type 2 diabetes: A Danish cohort study.

In individuals at increased risk of infections, e.g., patients with type 2 diabetes, low MBL may have detrimental effects. We used the Mendelian randomization principle to examine whether genetically low MBL is a risk factor for developing infections in patients with type 2 diabetes. Serum MBL (n = 7305) and MBL genotype (n = 3043) were determined in a nationwide cohort of patients with new type 2 diabetes and up to 8 years follow-up for hospital-treated infections and community-based antimicrobial prescriptions. The associations were examined in spline and Cox regression analyses. 1140 patients (16%) were hospitalized with an infection and 5077 patients (70%) redeemed an antimicrobial prescription. For low (≤100 μg/L) versus intermediate (101-1000 μg/L) serum MBL concentration, the adjusted hazard ratios (aHRs) were 1.13(95% confidence interval, 0.96-1.33) for any hospital-treated infections and 1.19(1.01-1.41) for bacterial infections. Low MBL expression genotype was not associated with risk of any hospital-treated infections except for diarrheal diseases (aHR 2.23[1.04-4.80]). Low MBL expression genotype, but not low serum MBL, was associated with increased risk for antimicrobial prescriptions (aHR 1.18[1.04-2.34] and antibacterial prescriptions 1.20[1.05-1.36]). Low MBL is a weak causal risk factor for developing infections in patients with type 2 diabetes.

Mannose-Binding Lectin and Risk of Cardiovascular Events and Mortality in Type 2 Diabetes: A Danish Cohort Study.

Mannose-binding lectin (MBL) is linked to risk of cardiovascular disease (CVD) in diabetes, but the nature of the association is unclear. We investigated the association between MBL and the risk of cardiovascular events (CVE) and all-cause mortality in type 2 diabetes. In a cohort study of 7,588 patients with type 2 diabetes, we measured serum MBL in 7,305 patients and performed MBL expression genotyping in 3,043 patients. We grouped serum MBL and MBL expression genotypes into three categories: low, intermediate, and high. Outcomes were CVE (myocardial infarction, stroke, coronary revascularization, unstable angina, or cardiovascular death) and all-cause mortality. The association with outcomes was examined by spline and Cox regression analyses. Serum MBL and CVE showed a U-shaped association. Compared with the intermediate serum MBL category, the adjusted hazard ratio (HR) for CVE was 1.82 (95% CI 1.34-2.46) for the low-MBL category and 1.48 (95% CI 1.14-1.92) for the high-MBL category. We found a similar U-shaped association for all-cause mortality, but with lower risk estimates. Compared with the intermediate MBL expression genotype, the adjusted HR for CVE was 1.40 (95% CI 0.87-2.25) for the low-expression genotype and 1.44 (95% CI 1.01-2.06) for the high-expression genotype. MBL expression genotype was not associated with all-cause mortality. Both serum MBL and MBL expression genotype showed a U-shaped association with CVE risk in individuals with type 2 diabetes. Our findings suggest that serum MBL is a risk factor for CVD in this population.

A prospective pilot study of pharmacogenetic-based dosing of 5-fluouracil (5-FU) and irinotecan (IRI) in patients (pts) with gastrointestinal (GI) malignancies.

e16138 Background: 5-FU and IRI are core components of chemotherapies for GI malignancies. Previous studies have shown that mutations in DPYP and TYMS predispose the pts to 5-FU toxicities. Mutations in UGT1A1 predispose pts to increased IRI toxicities. Retrospective data suggest that these mutations may have implications in selecting dosage and/or schedule of 5-FU and IRI. We present here a prospective study of upfront pharmacogenetic testing with tailored dose of respective drugs in pts with these mutations. Methods: Pts with GI malignancies were tested for DPYD, TYMS and UGT1A1 mutations before initiating 5-FU and/or IRI. Mutation analyses were performed at Quest Diagnostics Nichols Institute. Pts were dosed at 50% if DPYD was abnormal and 25% dose reduction if indicated by TYMS or UGT1A1 * 28 (homozygous) abnormality. Adverse events (AEs) were graded according to CTCAE v.5.0. We compared AEs to our previously collected data in DPYD, TYMS deficient pts who underwent genetic testing due to toxicity to 5-FU. Results: Of 226 pts screened, 5 pts had DPYP mutations with genotypes (3: c.1905+1G/A; 1: c.2846A/T; 1: c.557A/G). TYMS mutations were identified in 24 pts. For 3'-UTR, distributions were: intermediate expression genotype 4: INS/DEL, low expression genotype 5: DEL/DEL. For 5'TSER, distributions were: low expression genotypes (6:2R/2R; 3:2R/3RC; 4: 3RC/3RC) and high expression genotypes (2: 2R/3RG, 2: 3RG/3RC, 1: 3RG/3RG). UGT1A1*28 mutation was identified in 53 pts – 19 homozygous and 34 heterozygous. No grade ≥3 neutropenia was observed with reduced dose of IRI in UGT1A 1 variant pts compared to 33% reported in pts not tested. For TYMS and DPYD variants, no grade ≥3 AEs were seen. Comparison of AEs in pts with post treatment genetic testing is listed in Table. Conclusions: Pharmacogenetic based dosing of 5-FU and IRI led to less frequent, less severe toxicities and no death related to AEs was observed in our pts. This can improve pts’ quality of life and lessen economic burden of managing severe AEs. Currently, there are no formal guidelines regarding testing for DPYD, TYMS and UGT1A1. Although non-randomized, this study advocates for systemic screening of pharmacogenetic testing in pts with GI malignancies. [Table: see text]

Serotonergic Regulation and Cognition after Stroke: The Role of Antidepressant Treatment and Genetic Variation

Introduction: Serotonin affects several brain functions including cognition. The serotonin transporter (SERT) regulates brain serotonin levels through reuptake into neurons. The gene encoding this transporter, the SERT gene, has several functional polymorphisms affecting the number of transporters and thereby the serotonin levels. SERT gene expression may be important for cognition and selective serotonin reuptake inhibitors (SSRI) may improve cognition post stroke. We therefore examined the association between SERT genotypes, cognitive function and early treatment with the SSRI citalopram among non-depressed Caucasian stroke patients. Patients and Methods: SERT gene polymorphisms in 270 non-depressed first-ever acute ischemic stroke patients randomized to citalopram, n = 130, or placebo, n = 140, were investigated. Patients were genotyped for a length polymorphism (L = long and S = short allele) and a single nucleotide polymorphism (A/G substitution) dividing the L-allele into L_A and L_G. According to these genotypes, patients were further grouped according to low (S/S, L_G/S and L_G/L_G), medium (S/L_A and L_G/L_A), or high functional gene expression (L_AL_A). Cognition was measured by the Symbol Digit Modalities Test (SDMT) at 1 and 6 months. Mean SDMT scores according to genotype and randomization groups were compared using multiple logistic regression adjusting for age, stroke severity, premorbid functional status, and vascular risk factors including smoking, hypertension, and diabetes. Results: Stratified by genotype groups, there were no statistically significant differences in SDMT scores between randomization groups. Placebo-treated patients with low SERT expression genotypes, however, tended to have lower mean SDMT scores (at 1 month: 30.2, SD 10.8) compared to citalopram-treated patients (33.6, SD 13.7). Within the placebo group, the low genotype expression patients had significantly lower adjusted mean SDMT scores at 1 month compared to the high genotype expression patients (adjusted mean difference of –6 points, CI –12.0 to –0.05). We found similar results at 6 months, although not statistically significant. The genotype expression was not associated with SDMT scores among citalopram-treated patients. Conclusion: There was no difference in cognition between citalopram and placebo-treated patients according to the genotype group. Our results indicate, however, that low expression SERT genotype may contribute to reduced cognitive function post stroke as placebo-treated patients with low SERT expression tended to score lower on the SDMT. The significant difference in SDMT scores between low and high expression patients was present only in the placebo-treated group, thereby warranting further exploration of the potential effect of early citalopram treatment on cognitive functioning. Our results are preliminary and need replication in larger-scale studies.

The Serotonin Transporter Gene Polymorphisms and Risk of Ischemic Stroke

Introduction: Serotonin is known as a neurotransmitter; however, it also plays an important role in platelet aggregation as it is released upon platelet activation. The serotonin transporter (SERT) is responsible for the uptake of serotonin into platelets. Functional polymorphisms in the SERT gene may influence platelet activity, as they result in different levels of transporters and thereby different levels of serotonin in platelets. SERT gene polymorphisms have thus been associated with the risk of myocardial infarction. A similar association may exist between SERT gene polymorphisms and stroke. However, to our knowledge, this potential association has not previously been studied. We therefore aimed to investigate the association between polymorphisms in the SERT gene and the risk of ischemic stroke/transitory ischemic attack (TIA). Materials and Methods: We conducted a case-control study including 834 consecutively admitted first-ever Caucasian ischemic stroke patients/TIA from Aarhus University Hospital, Denmark and 571 healthy controls. The control group comprised a sample from the Danish working population, who were all employees in the public sector in the Central Denmark Region. Two polymorphisms, the length variation (short = S/long = L) in the serotonin-transporter-linked polymorphic region and a single-nucleotide (A/G) polymorphism (rs25531) were studied. The genotypes were grouped according to the functional activity: SS, SLG and LGLG (low expression), SLA, LGLA (medium expression), and LALA (high expression). Data were analyzed using logistic regression and results presented as OR with 95% CI. Results: The high-expression genotype was associated with a lower risk of ischemic stroke/TIA when compared to both the medium expression genotype (OR 0.72, 95% CI 0.56–0.93) and the low-expression genotype (OR 0.75, 95% CI 0.55–1.01) as well as the combination of the low and medium expression genotypes (OR 0.73, 95% CI 0.58–0.93). The lower OR estimates associated with the high-expression genotype were consistent across all stroke subtypes, although not statistically significant. The results remained virtually unchanged, although not reaching statistical significance, when adjusting for age and gender. Conclusion: The presence of the high expression SERT genotype (LALA) may be associated with a lower risk of ischemic stroke/TIA. This is, to our knowledge, the first study examining the SERT gene polymorphisms and the risk of stroke. The present results raise interesting considerations for future personalized medicine potential, and we argue that further larger-scale studies with sufficient power to study subgroups according to stroke etiology and stroke-onset age are needed.

The triallelic serotonin transporter gene polymorphism is associated with depressive symptoms in adults with chronic pain.

BackgroundThe serotonin (5-HT) transporter-linked polymorphic region (5-HTTLPR) moderates the relationship between stressful life events and depression. Given the high prevalence of depression in chronic pain, the primary aim of this preliminary study was to investigate the associations between the 5-HTTLPR and the severity of depressive symptoms in a cohort of adults with chronic pain.MethodsAdults with chronic pain who were consecutively admitted to an outpatient pain rehabilitation program and met inclusion criteria were recruited for study participation (n=277). Individuals were genotyped for the 5-HTTLPR (including rs25531) and categorized as high, intermediate, or low expressors of the 5-HT transporter. The severity of depressive symptoms at admission was measured by using the Center for Epidemiologic Depression scale (CES-D).ResultsThe distribution of the high-, intermediate-, and low-expressing genotypes was 61 (22%), 149 (54%), and 67 (24%), respectively. The Hardy–Weinberg P-value was 0.204, which indicated no departure from equilibrium. A main effect of 5-HTTLPR was observed for depressive symptoms (P=0.040) where Center for Epidemiologic Depression scale (CES-D) scores were significantly greater in the low-expressing group compared to the high- (P=0.019) and intermediate (P=0.029)-expressing groups. In multivariate multinomial logistic regression analysis adjusted for age, sex, pain severity, pain catastrophizing, and pain anxiety, greater CES-D scores were significantly associated with the 5-HTTLPR low-expressing group compared to the high-expressing group (P=0.023), but not for the low-expressing group compared to the intermediate-expressing group (P=0.056).ConclusionThese preliminary findings suggest that the triallelic 5-HTTLPR could influence the severity of depressive symptoms in adults with chronic pain. Individuals with chronic pain may be particularly vulnerable to the moderating effects of 5-HTTLPR due to high levels of pain-related stress that are inherently present in this population.

Prograf produces more benefits for CYP3A5 low expression patients in early stage after kidney transplantation.

This study is to analyze concentration changes of the prolonged-release and shorter-acting formulation of tacrolimus in patients with different CYP3A5 genotypes after kidney transplantation. A single-factor retrospective analysis was performed in patients underwent allogeneic kidney transplantation with postoperative administration of Advagraf or Prograf in our hospital from May 2013 to June 2014. The CYP3A5 genotypes were determined, and tacrolimus trough concentrations in whole blood were measured within 28days after transplantation. The rates of acute rejection rate, chronic rejection and infection were recorded and compared after one year follow-up after surgery. The study included 106 patients administered Advagraf (45 cases) or Prograf (61 cases). The low expression genotype of CYP3A5 was detected in 40 (37.7%) patients. A higher dose of Advagraf was required to increase the tacrolimus trough concentrations within 21days after transplantation. Moreover, a higher dose for Advagraf than Prograf was required to increase the tacrolimus trough concentrations in low expression patients. In the low expression patients, Prograf more frequently achieved the target tacrolimus trough concentrations within seven days after transplantation (five days: 7.14% vs. 84%, P=0.001; seven days: 33.33% vs. 77.78%, P=0.001). The patient and kidney graft survival rates one year after transplantation both were 100%. The estimated glomerular filtration rate showed no significant difference between different CYP3A5 phenotypes or formulations of tacrolimus (P>0.05). However, the incidence of infections was higher in the Advagraf group in low expression patients (P<0.05). Tacrolimus of different formulations had different impact on patients with different CYP3A5 genotypes after kidney transplantation.

Interacting effect of MAOA genotype and maternal prenatal smoking on aggressive behavior in young adulthood.

Findings on the etiology of aggressive behavior have provided evidence for an effect both of genetic factors, such as variation in the monoamine oxidase A (MAOA) gene, and adverse environmental factors. Recent studies have supported the existence of gene×environment interactions, with early experiences playing a key role. In the present study, the effects of prenatal nicotine exposure, MAOA genotype and their interaction on aggressive behavior during young adulthood were examined. In a sample of 272 young adults (129 males, 143 females) from an epidemiological cohort study, smoking during pregnancy was measured with a standardized parent interview at the offspring's age of 3months. Aggressive behavior was assessed between the ages of 19 and 25years using the Young Adult Self-Report. DNA was genotyped for the MAOA 5' untranslated region variable number of tandem repeats polymorphism (VNTR). Results revealed a significant interaction between MAOA and smoking during pregnancy, indicating higher levels of aggressive behavior in young adults carrying the MAOA low-expressing genotype who had experienced prenatal nicotine exposure (n=8, p=.025). In contrast, in carriers of the MAOA high-expressing genotype, maternal smoking during pregnancy had no effect on aggressive behavior during young adulthood (n=20, p=.145). This study extends earlier findings demonstrating an interaction between MAOA genotype and prenatal nicotine exposure on aggressive behavior into young adulthood. The results point to the long-term adverse effects of smoking during pregnancy on the offspring's mental health, possibly underlining the importance of smoking cessation during pregnancy. According to the nature of the study (particularly sample size and power), analyses are exploratory and results need to be interpreted cautiously.

Influence of the polymorphism of the DUSP14 gene on the expression of immune-related genes and development of pulmonary tuberculosis

Recently, a genome-wide screening identified a functional single-nucleotide polymorphism in dual-specificity phosphatase 14 gene (DUSP14), which was associated with pulmonary tuberculosis (TB) in a West African study. DUSP14 regulates T-cell proliferation and cytokine production in a negative way via dephosphorylation and inactivation of key signaling molecules. The aim of this study is to further explore the possible significance of the DUSP14 polymorphism. Total RNA was extracted from the whole blood of 109 healthcare workers (HCWs) in Vietnam and subjected to quantitative reverse-transcription PCR for DUSP14 and 20 immune-related genes. DUSP14 rs1051838 was genotyped in 502 new pulmonary TB patients and 506 healthy controls. Among disease-free individuals (HCWs), T-helper type-1 (Th1)-related genes, interferon-gamma receptor 2 (IFNGR2) and signal transducer and activator of transcription-1 (STAT1) mRNA levels significantly increased as the number of A alleles of rs1051838 increased, whereas the DUSP14 mRNA level tended to decrease. The AA genotype was associated with protection against active TB in younger patients (⩽45 years old, OR=0.63, 95% CI 0.44-0.90). Our results suggest that a low-expression genotype of DUSP14 accompanied by high transcript levels of Th1 immune-related genes may confer protection against early TB development.

&amp;lt;i&amp;gt;MBL2&amp;lt;/i&amp;gt; Gene Polymorphism and the Association with Neonatal Sepsis in Egyptian Neonates, a Case Control Study

Mannose binding lectin (MBL) is an important component of innate immunity particularly in neonates whose adaptive immunity is not fully developed. Polymorphism in MBL2 gene promoter and exon1 determines MBL serum level and function. The aim of this study was to investigate the frequency of different MBL2 genotypes in neonatal sepsis among patients of neonatal intensive care unit (NICU). Two hundred and forty-five neonates were enrolled in this study (127 infected and 118 uninfected controls). Multiplex PCR and double amplification refractory mutation system (dARMS) were used for typing of MBL2 exon1 and promoter respectively. Klebsiella species were the most frequently isolated organisms (22.8%). There is no statistical significance difference in the distribution of different expression genotypes between infected group and controls (P = 0.11). However, prevalence of low MBL2 expression genotypes (XA/O and O/O) was higher in infected patients compared to control group (patients 25.2% and controls 15.3%). Low and medium MBL2 expression genotypes were mostly associated with Gram-negative bacterial infections (18.9% and 22.8%) respectively. A statistically significant association of Gram-negative bacterial infections with low MBL2 expression genotypes was found (P = 0.02). Higher frequency of AB and BB genotypes was observed (31.5% and 7.9%) in patients group compared to control, but without statistical significant difference.

A study of the association between the kynurenine-3-monooxygenase gene and depression

To study the association between the kynurenine 3-monooxygenase (KMO) and depression. КМО rs2275163 (C/T) and rs1053230 (A /G) polymorphisms were genotyped in patients diagnosed with depression (the main group) and age - and sex-matched healthy people. The rs2275163 polymorphism was not associated with depression. There was the association between the rs1053230 polymorphism and depression. The frequency of the low expression genotype GG was higher in the main group compared to controls (р=0.001, ОШ 2.8 (95% ДИ 1.73-4.24). This genotype was earlier reported to be associated with the increased levels of kynurenic acid in patients with bipolar disorders. The genotype GG can be considered as a risk factor of depression.

Increased risk of severe fluoropyrimidine-associated toxicity in patients carrying a G to C substitution in the first 28-bp tandem repeat of the thymidylate synthase 2R allele.

The fluoropyrimidines act by inhibiting thymidylate synthase (TS). Recent studies have shown that patients' risk of severe fluoropyrimidine-associated toxicity is affected by polymorphisms in the 5'-untranslated region of TYMS, the gene encoding TS. A G>C substitution in the promoter enhancer region of TYMS, rs183205964 (known as the 2RC allele), markedly reduces TS activity in vitro, but its clinical relevance is unknown. We determined rs183205964 in 1605 patients previously enrolled in a prospective multicenter study. Associations between putative low TS expression genotypes (3RC/2RC, 2RG/2RC, and 2RC/2RC) and severe toxicity were investigated using univariable and multivariable logistic regression. Activity of TS and TYMS gene expression were determined in peripheral blood mononuclear cells (PBMCs) of a patient carrying genotype 2RC/2RC and of a control group of healthy individuals. Among 1,605 patients, 28 patients (1.7%) carried the 2RC allele. Twenty patients (1.2%) carried a risk-associated genotype (2RG/2RC, n=13; 3RC/2RC, n=6; and 2RC/2RC, n=1), the eight remaining patients had genotype 3RG/2RC. Early severe toxicity and toxicity-related hospitalization were significantly more frequent in risk-associated genotype carriers (OR 3.0, 95%CI 1.04-8.93, p=0.043 and OR 3.8, 95%CI 1.19-11.9, p=0.024, respectively, in multivariable analysis). The patient with genotype 2RC/2RC was hospitalized twice and had severe febrile neutropenia, diarrhea, and hand-foot syndrome. Baseline TS activity and gene expression in PBMCs of this patient, and a healthy individual with the 2RC allele, were found to be within the normal range. Our study suggests that patients carrying rs183205964 are at strongly increased risk of severe, potentially life-threatening, toxicity when treated with fluoropyrimidines.

Increased all-cause mortality in patients with type 1 diabetes and high-expression mannan-binding lectin genotypes: a 12-year follow-up study.

Mannan-binding lectin (MBL) is a complement-activating carbohydrate-recognizing molecule associated with diabetic nephropathy. MBL is associated with all-cause mortality in type 2 diabetes, but whether MBL is associated with mortality in type 1 diabetes remains unknown. We therefore aimed to investigate this. We studied an existing 12-year prospective cohort with type 1 diabetes with 198 patients with diabetic nephropathy (121 men, age 41 years [95% CI 40-42], estimated glomerular filtration rate [eGFR] 67 mL/min/1.73 m(2) [95% CI 63-70]) and 174 normoalbuminuric patients (103 men, age 43 years [95% CI 41-44], eGFR 93 mL/min/1.73 m(2) [95% CI 91-95]). Mortality rates were compared according to the concentration-determining MBL2 genotype or the MBL concentration. Patients were classified as having high or low MBL expression genotypes. The effect of MBL concentration was estimated by comparing patients with MBL concentrations above or below the median. Ninety-eight patients died during follow-up. The unadjusted hazard ratio (HR) for all-cause mortality was 1.61 (95% CI 1.07-2.43) for patients with high MBL expression genotypes versus patients with low MBL expression genotypes (P = 0.023). All-cause mortality was higher in patients with MBL concentrations above the median than in patients with MBL concentrations below the median (unadjusted HR 1.90 [95% CI 1.26-2.87], P = 0.002). High MBL expression genotypes and high MBL concentrations are both associated with increased mortality rates in type 1 diabetes compared with low MBL expression genotypes and low MBL concentrations.

Prognostic implications of thymidylate synthase gene polymorphisms in patients with advanced small bowel adenocarcinoma treated with first-line fluoropyrimidine-based chemotherapy.

Thymidylate synthase (TS) gene polymorphisms such as tandem repeat (TR) polymorphisms and single-nucleotide polymorphisms (SNPs) affect transcriptional efficiency of the TS gene and may be prognostic markers for fluoropyrimidine-based therapy in various gastrointestinal cancers. However, data for TS polymorphisms on clinical outcomes in advanced small bowel adenocarcinoma (SBA) are limited. We retrospectively enrolled 58 locally advanced/metastatic SBA patients treated with first-line fluoropyrimidine-based chemotherapy and analyzed the relationship between TS genotypes and clinical outcomes in 30 patients who were available for tumor tissue. Based on TR polymorphisms and a G>C SNP in the promoter region of the TS gene, 74% of patients had high TS expression genotypes (2R/3RG, 3RG/3RC, 3RG/3RG); the remainder had low TS expression genotypes (2R/2R, 2R/3RC, 3RC/3RC). After a median follow-up of 48.8 months, median progression-free survival (PFS) and overall survival (OS) in all patients were 6.0 and 11.3 months, respectively. However, patients with low TS expression genotypes had better median PFS (12.8 vs. 4.3 months, P=0.027) and OS (28.8 vs. 8.9 months, P=0.025) than those with high TS expression genotypes. In multivariate analysis, poor Eastern Cooperative Oncology Group performance status [hazard ratio (HR), 2.85; 95% CI, 1.02-7.93] and high TS expression genotypes (HR, 3.49; 95% CI, 1.13-10.78) were independent prognostic factors for worse OS. Therefore, TS genotypes, based on a G>C SNP in the TR sequence of the TS gene, may be a useful biomarker for predicting outcomes for fluoropyrimidine-based chemotherapy in patients with locally advanced/metastatic SBA.

Therapygenetics: 5-HTTLPR genotype predicts the response to exposure therapy for agoraphobia

This study was intended to assess the extent to which the low-expression allele of the serotonin transporter gene promoter predicts better response to exposure-based behavior therapy in patients with panic disorder with agoraphobia (PDA). Ninety-nine patients with PDA underwent a 1-week in vivo exposure-based behavior therapy program and provided saliva samples to extract genomic DNA and classify individuals according to four allelic forms (SA, SG, LA, LG) of the 5-HTT-linked polymorphic region (5-HTTLPR). We determined whether the 5-HTTLPR genotype predicted change in avoidance behavior in PDA following treatment. After controlling for pre-treatment avoidance behavior, the 5-HTTLPR low-expression genotypes showed a more favorable response to exposure therapy two weeks following treatment, compared to the other patients. This study suggests a genetic contribution to treatment outcome following behavior therapy and implicates the serotonergic system in response to exposure-based treatments in PDA.

Transcriptome profiling of human hippocampus dentate gyrus granule cells in mental illness

This study is, to the best of our knowledge, the first application of whole transcriptome sequencing (RNA-seq) to cells isolated from postmortem human brain by laser capture microdissection. We investigated the transcriptome of dentate gyrus (DG) granule cells in postmortem human hippocampus in 79 subjects with mental illness (schizophrenia, bipolar disorder, major depression) and nonpsychiatric controls. We show that the choice of normalization approach for analysis of RNA-seq data had a strong effect on results; under our experimental conditions a nonstandard normalization method gave superior results. We found evidence of disrupted signaling by miR-182 in mental illness. This was confirmed using a novel method of leveraging microRNA genetic variant information to indicate active targeting. In healthy subjects and those with bipolar disorder, carriers of a high- vs those with a low-expressing genotype of miR-182 had different levels of miR-182 target gene expression, indicating an active role of miR-182 in shaping the DG transcriptome for those subject groups. By contrast, comparing the transcriptome between carriers of different genotypes among subjects with major depression and schizophrenia suggested a loss of DG miR-182 signaling in these conditions.

Interleukin-6 G-174C gene polymorphism and susceptibility to upper respiratory tract infection among endurance athletes

The aim of this study was to investigate the influence of interleukin (IL)-6 gene polymorphisms on upper respiratory tract infection (URTI) incidence. To this end, 100 healthy elite male athletes participating in the study were classified as either healthy or prone to frequent URTI. Blood samples and DNA isolation, multiplex polymerase chain reaction, and Taqman real-time polymerase chain reaction were carried out. Genomic DNA was extracted from peripheral leukocytes of whole blood samples using the QIAmp DNA Blood Mini Kit according to the manufacturer's protocols. For comparison of the distribution of genotypes between the two groups and for estimating odds ratios for URTI susceptibility in relation to the IL-6 polymorphism, Pearson's χ2 and logistic regression methods were used, respectively. The IL-6-174 genotype distribution differed between athletes with URTI and healthy athletes (χ2 = 11.68, p = 0.003). The IL-6 low-expression genotype (CC), relative to the other two genotypes combined (GC + GG), was associated with a tendency for an increased likelihood of frequent URTI (odds ratio: 3.33, 95% confidence interval: 1.40–7.92; p = 0.006). In conclusion, findings from this study have identified a potential role of genetic variation in influencing the risk for URTI in athletic populations and single nucleotide polymorphisms in the IL-6 genes were associated with an altered risk profile. These measures may have a predictive value in the identification of individuals who are more likely to experience recurrent infections when exposed to high physical stress in the areas of athletic endeavor.