Preference of juvenile tiger puffer for light spectrum and tank colours based on different body size and breeding background.

As important environmental factors, the light spectra and tank colours have not received sufficient attention. Most fishes have the ability to perceive environment, distinguish colours, and exhibit preferences or aversions towards different environments, which can provide a reference for the design of their rearing environment. Tiger puffer (Takifugu rubripes) is an important mariculture species in China and East Asia, but its preference for illumination spectra and tank colours is unclear. This study focuses on the preferences of juvenile tiger puffers for different spectra and tank background colours in different rearing backgrounds and body sizes. The experiments were conducted in a preference testing device, and the behavioural videos were recorded and analysed using a motion behaviour tracking system (EthoVision XT 12). The results show that the puffers showed preference for short-wavelength lights ((i.e., cyan, green, etc.), avoidance of long-wavelength light (i.e., red) and less stay time in the full light spectrum and dark. For tank colours, the puffers showed a preference for light background colours (i.e., white), and avoidance of deep background colours (i.e., dark, red, etc.). Fish body sizes and original breeding environment could significantly affect the selective preference of juvenile puffer (P < 0.05). Large puffers preferred green tank colour than small ones, while small ones preferred grey and red. The puffers reared in green light and grey tank for 3 months preferred green light spectrum and green tank colour compared with those reared in full spectrum and grey tank, while the fish reared in full spectrum preferred grey tank colour and area without light. It was also found that the movement rate of juvenile puffers was affected by the light spectra and tank colours and was positively correlated with light wavelength (P < 0.05). Therefore, for tiger puffer breeding, short-wavelength light spectrums (cyan, green, etc.) and light-coloured tank backgrounds (white) are recommended. Long-wavelength Light-emitting diodes and dark tank colours should be avoided in breeding. This study would provide a reference basis for fish light spectra and background colour preference studies, as well as for the improvement of breeding welfare and production efficiency of juvenile tiger puffer.

Modeling Intention-Based Critical Determinants of E-Commerce Utilization: Emerging Business Models and Transformation in the Digital World.

Companies in the world today understand that keeping users in touch is essential to enhancing their trust. The primary objective of this study was to determine the intention-based critical determinants of E-commerce utilization in China from the end users' perspective. We developed a framework that identifies the factors that influence E-commerce utilization in China. Besides, we introduced observational research (data analysis) conducted in a real-world E-commerce sense. Results are based on a sample of 400 respondents by employing a comprehensive questionnaire survey. The structural equation modeling (SEM) and the partial least squares (PLS) regression approach was used to analyze the data. Study results show that perceived usefulness, perceived ease of use, reputation, trust in vendors, and purchase frequency significantly influence consumers' intention to use E-commerce systems. Research outcomes emphasize transforming social norms, raising consumers' awareness, redesigning policy frameworks, and highlighting the paybacks that E-commerce offers through integrative and consistent efforts.

Profile of gene expression changes during estrodiol-17ß-induced feminization in the Takifugu rubripes brain.

BACKGROUND: As the critical tissue of the central nervous system, the brain has been found to be involved in gonad development. Previous studies have suggested that gonadal fate may be affected by the brain. Identifying brain-specific molecular changes that occur during estrodiol-17ß (E2) -induced feminization is crucial to our understanding of the molecular control of sex differentiation by the brains of fish. RESULTS: In this study, the differential transcriptomic responses of the Takifugu rubripes larvae brain were compared after E2 treatment for 55 days. Our results showed that 514 genes were differentially expressed between E2-treated-XX (E-XX) and Control-XX (C-XX) T. rubripes, while 362 genes were differentially expressed between E2-treated-XY (E-XY) and Control-XY (C-XY). For example, the expression of cyp19a1b, gnrh1 and pgr was significantly up-regulated, while st, sl, tshß, prl and pit-1, which belong to the growth hormone/prolactin family, were significantly down-regulated after E2 treatment, in both sexes. The arntl1, bhlbe, nr1d2, per1b, per3, cry1, cipc and ciart genes, which are involved in the circadian rhythm, were also found to be altered. Differentially expressed genes (DEGs), which were identified between E-XX and C-XX, were significantly enriched in neuroactive ligand-receptor interaction, arachidonic acid metabolism, cytokine-cytokine receptor interaction and the calcium signaling pathway. The DEGs that were identified between E-XY and C-XY were significantly enriched in tyrosine metabolism, phenylalanine metabolism, arachidonic acid metabolism and linoleic acid metabolism. CONCLUSION: A number of genes and pathways were identified in the brain of E2-treated T. rubripes larvae by RNA-seq. It provided the opportunity for further study on the possible involvement of networks in the brain-pituitary-gonadal axis in sex differentiation in T. rubripes.

Genetic Associations With Stable Warfarin Dose Requirements in Han Chinese Patients.

ABSTRACT: Warfarin is a commonly prescribed anticoagulant for valvular heart disease that plays an important role in clinical management to prevent thrombotic events. In this study, we aim to perform a comprehensive study to investigate the genetic biomarkers of stable warfarin dose in the Han Chinese population. We performed an integrative study on 211 Han Chinese patients with valvular heart disease. A total of 40 single nucleotide polymorphisms (SNPs) in 10 important genes (CYP2C9, VKORC1, ABCB1, CYP4F2, APOE, PROC, GGCX, EPHX1, CALU, and SETD1A) which are involved in the warfarin metabolic pathway and equilibrium of coagulation and anticoagulation were selected. We applied MassARRAY technology to genotype the 40 SNPs identified in these Han Chinese patients. Our results showed that 13 SNPs on 6 genes (CYP2C9, VKORC1, ABCB1, PROC, EPHX1, and SETD1A) were associated with the individual stable warfarin dose. Two VKORC1 SNPs (rs9934438 and rs2359612) were the strongest genetic factors determining warfarin dose requirements (P = 8 × 10-6 and 9 × 10-6, respectively). Rs4889599 in SETD1A was first reported to be associated with warfarin dose at a significant level of 0.001 in our study (Padjust = 0.040 after Bonferroni correction). We discovered that genetic variants in CYP2C9, VKORC1, ABCB1, PROC, EPHX1, and SETD1A may affect the stable warfarin dose requirement in Han Chinese patients with valvular disease. The discovery of these potential genetic markers will facilitate the development of advanced personalized anticoagulation therapy in Han Chinese patients.

p.E95K mutation in Indian hedgehog causing brachydactyly type A1 impairs IHH/Gli1 downstream transcriptional regulation.

BACKGROUND: Brachydactyly type A1 (BDA1, OMIM 112500) is a rare inherited malformation characterized primarily by shortness or absence of middle bones of fingers and toes. It is the first recorded disorder of the autosomal dominant Mendelian trait. Indian hedgehog (IHH) gene is closely associated with BDA1, which was firstly mapped and identified in Chinese families in 2000. Previous studies have demonstrated that BDA1-related mutant IHH proteins affected interactions with its receptors and impaired IHH signaling. However, how the altered signaling pathway affects downstream transcriptional regulation remains unclear. RESULTS: Based on the mouse C3H10T1/2 cell model for IHH signaling activation, two recombinant human IHH-N proteins, including a wild type protein (WT, amino acid residues 28-202) and a mutant protein (MT, p.E95k), were analyzed. We identified 347, 47 and 4 Gli1 binding sites in the corresponding WT, MT and control group by chromatin immunoprecipitation and the overlapping of these three sets was poor. The putative cis regulated genes in WT group were enriched in sensory perception and G-protein coupled receptor-signaling pathway. On the other hand, putative cis regulated genes were enriched in Runx2-related pathways in MT group. Differentially expressed genes in WT and MT groups indicated that the alteration of mutant IHH signaling involved cell-cell signaling and cellular migration. Cellular assay of migration and proliferation validated that the mutant IHH signaling impaired these two cellular functions. CONCLUSIONS: In this study, we performed integrated genome-wide analyses to characterize differences of IHH/Gli1 downstream regulation between wild type IHH signaling and the E95K mutant signaling. Based on the cell model, our results demonstrated that the E95K mutant signaling altered Gli1-DNA binding pattern, impaired downstream gene expressions, and leaded to weakened cellular proliferation and migration. This study may help to deepen the understanding of pathogenesis of BDA1 and the role of IHH signaling in chondrogenesis.

Functional Characterization of Human CYP2C9 Allelic Variants in COS-7 Cells.

Variability in activity of CYP2C9, which is involved in the metabolism of approximately 15% of current therapeutic drugs, is an important contributor to interindividual differences in drug response. To evaluate the functional alternations of CYP2C9(*)2, CYP2C9(*)3, CYP2C9(*)8, CYP2C9(*)11 and CYP2C9(*)31, identified in our previous study in Chinese Han population, allelic variants as well as the wild-type CYP2C9 were transiently expressed in COS-7 cells. Kinetic parameters (Km, Vmax, and Clint) for S-warfarin 7-hydroxylation by these recombinant CYP2C9s were determined. Relative to CYP2C9.1, recombinant CYP2C9.3 and CYP2C9.11 exhibited significantly higher Km values, and all allelic variants showed significantly decreased Vmax and Clint values. Among all allelic variants, catalytic activity of CYP2C9.3 and CYP2C9.11 reduced the most (8.2% and 9.8% of Clint ratio, respectively; P < 0.001). These findings should be useful for predicting the phenotype profiles of CYP2C9 in Chinese Han population, comparing the functional results of these alleles accurately, and finally optimizing pharmacotherapy of drug treatment.

Hsa-miR-27a is involved in the regulation of CYP3A4 expression in human livers from Chinese Han population.

AIM: The huge interindividual difference of CYP3A4 expression may contribute to the variability of drug response. Post-transcriptional regulation of CYP3A4 remains elusive although transcriptional regulation has been studied much more clearly. microRNAs (miRNAs) were reported to be one of factors to regulate the expression of CYP3A4 previously. MATERIALS & METHODS: Based on the in silico prediction of 3'-UTR-bindind site of microRNA-27a (miR-27a), the transcriptional and post-transcriptional regulation of miR-27a were investigated through luciferase reporter assay, real-time PCR and immunoblot. RESULTS: The significantly decrease of CYP3A4 3'-UTR-luciferase activity in human embryonic kidney 293 and Hep3B cells was detected after transfected with plasmid that expressed miRNA-27a in luciferase reporter assay. Correlation study was conducted in human livers (n = 26) and significant correlation has been discovered between miRNA-27a and CYP3A4 mRNA and protein level. CONCLUSION: Together, these findings suggest that miR-27a might be involved in the regulation of CYP3A4 gene expression.

Association of dopamine receptor D1 (DRD1) polymorphisms with risperidone treatment response in Chinese schizophrenia patients.

Evidence suggests that dopamine receptor D1 (DRD1) may be involved in the pathophysiology of schizophrenia and the pharmacodynamics of antipsychotics. We conducted a comprehensive pharmacogenomics study to investigate the association of genetic polymorphisms in DRD1 with treatment response to risperidone. Two independent cohorts of Han Chinese schizophrenic patients (n = 185) from two different geographic areas treated with risperidone monotherapy for 4 weeks and four SNPs (rs5326, rs4867798, rs4532 and rs686) in the DRD1 gene were analyzed. Clinical symptoms were evaluated using the Positive and Negative Syndrome Scale (PANSS). The definition of risperidone response is based on a cut-off of 50% in terms of corrected percent change of PANSS score. The significant confounding effects of non-genetic factors were included as covariates for adjustment. No significant association of DRD1 polymorphisms with risperidone treatment response was found in either single marker or haplotype analysis in this study. The current results provide the first evidence that DRD1 polymorphisms may not influence the clinical efficacy of risperidone in Chinese schizophrenia patients.

A pharmacogenetic study of risperidone on chemokine (C-C motif) ligand 2 (CCL2) in Chinese Han schizophrenia patients.

Previous observations of the pathophysiological distribution and pharmacological profile of the chemokine (C-C motif) ligand 2 (CCL2) have indicated its potential role in antipsychotic drug actions. More information on the pharmacogenetics of CCL2 may therefore be useful in developing individualized therapy. However, to our knowledge, rare studies have been reported in this area. This investigation was attempted to clarify whether CCL2 polymorphism could affect risperidone efficacy. We genotyped four SNPs (rs4795893, rs1024611, rs4586 and rs2857657) distributed throughout the CCL2 gene and examined them for association using the Positive and Negative Syndrome Scale (PANSS) score in two independent cohorts of Chinese schizophrenic patients (n = 208) from two different geographic areas, following an 8-week period of risperidone monotherapy. We found that all genotyped SNPs were significantly associated with risperidone treatment (rs4795893: p = 1.66E-04, rs4586: p = 0.001, rs2857657: p = 0.004, at week 4, in ANOVA). Our results indicate that there may be some effect of variations in the CCL2 gene on therapeutic efficacy of risperidone, and the associated polymorphisms may be a potential genetic marker for predicting the therapeutic effect of risperidone.

A systematically combined genotype and functional combination analysis of CYP2E1, CYP2D6, CYP2C9, CYP2C19 in different geographic areas of mainland China--a basis for personalized therapy.

The cytochrome P450 is the major enzyme involved in drug metabolism. Single CYP genotypes and metabolic phenotypes have been widely studied, but no combination analysis has been conducted in the context of specific populations and geographical areas. This study is the first to systematically analyze the combined genotypes and functional combinations of 400 samples of major CYP genes--CYP2E1, CYP2D6, CYP2C9, and CYP2C19 in four geographical areas of mainland China. 167 different genotype combinations were identified, of which 25 had a greater than 1% frequency in the Chinese Han population. In addition, phenotypes of the four genes for each sample were in line with the predictions of previous studies of the four geographical areas. On the basis of the genotype classification, we were able to produce a systemic functional combinations analysis for the population. 25 of the combinations detected had at least two non-wild phenotypes and four showed a frequency above 1%. A bioinformatics analysis of the relationship between particular drugs and multi-genes was conducted. This is the first systematic study to analyze genotype combinations and functional combinations across whole Chinese population and could make a significant contribution in the field of personalized medicine and therapy.

Identification of aberrant microRNA expression pattern in pediatric gliomas by microarray.

BACKGROUND: Brain tumor remains the leading cause of disease-related death in children. Many studies have focused on the complex biological process involved in pediatric brain tumors but little is know about the possible role of microRNAs in the genesis of these tumors. METHODS: In this study, we used a microRNA microarray assay to study the expression pattern of microRNAs in pediatric gliomas and matched normal tissues. RESULTS: We found 40 differentially expressed microRNAs, among which miR-1321, miR-513b, miR-769-3p were found be related to cancer genesis for the first time. The expression of selected microRNAs were then confirmed by qRT-PCR. Furthermore, GO and pathway analysis showed that the target genes of the 40 differentially expressed microRNAs were significantly enriched in nervous system-related and tumor-related biological processes and signaling pathways. Additionally, an apoptosis-related network of microRNA-mRNA interaction, representing the critical microRNAs and their targets, was constructed based on microRNA status. CONCLUSIONS: In the present study we identified the changed expression pattern of microRNAs in pediatric gliamas. Our study also provides a better understanding of pediatric brain tumor biology and may assist in the development of less toxic therapies and in the search for better markers for disease stratification. VIRTUAL SLIDES: The virtual slide(s) for this article can be found here: http://www.diagnosticpathology.diagnomx.eu/vs/1323049861105720.

Quantitative assessment of the association between rs2046210 at 6q25.1 and breast cancer risk.

Genome-wide association studies (GWAS) have identified several genetic susceptibility loci for breast cancer (BC). One of them, conducted among Chinese women, found an association of rs2046210 at 6q25.1 with the risk of BC recently. Since then, numerous association studies have been carried out to investigate the relationship between this polymorphism and BC risk in various populations. However, these have yielded contradictory results. We therefore performed a meta-analysis to clarify this inconsistency. Overall, a total of 235003 subjects based on 13 studies were included in our study. Significantly increased BC risk was detected in the pooled analysis [allele contrast: OR = 1.13, 95%CI = 1.10-1.17, P(Z) <10(-5), P(Q) <10(-4); dominant model: OR = 1.21, 95%CI = 1.14-1.27, P(Z) <10(-5), P(Q) <10(-4); recessive model: OR = 1.18, 95%CI = 1.12-1.24, P(Z) <10(-5), P(Q) = 0.04]. In addition, our data revealed that rs2046210 conferred greater risk in estrogen receptor (ER)-negative tumors [OR = 1.27, 95%CI = 1.15-1.40, P(Z) <10(-5), P(Q) <10(-4)] than in ER-positive ones [OR = 1.18, 95%CI = 1.09-1.28, P(Z) <10(-4), P(Q) = 0.0003]. When stratified by ethnicity, significant associations were found in Caucasian and Asian populations, but not detected among Africans. There was evidence of heterogeneity (P<0.05), however, the heterogeneity largely disappeared after stratification by ethnicity. The present meta-analysis demonstrated that the rs2046210 polymorphism may be associated with increased BC susceptibility, but this association varies in different ethnicities.

Pharmacogenomics can improve antipsychotic treatment in schizophrenia.

Schizophrenia is a widespread mental disease with a prevalence of about 1% in the world population, and heritability of up to 80%. Drug therapy is an important approach to treating the disease. However, the curative effect of antipsychotic is far from satisfactory in terms of tolerability and side effects. Many studies have indicated that about 30% of the patients exhibit little or no improvements associated with antipsychotics. The response of individual patients who are given the same dose of the same drug varies considerably. In addition, antipsychotic drugs are often accompanied by adverse drug reactions (ADRs), which can cause considerable financial loss in addition to the obvious societal harm. So, it is strongly recommended that personalized medicine should be implemented both to improve drug efficacy and to minimize adverse events and toxicity. There is therefore a need for pharmacogenomic studies into the factors affecting response of schizophrenia patients to antipsychotic drugs to provide informed guidance for clinicians. Individual differences in drug response is due to a combination of many complex factors including ADEM (absorption, distribution, metabolism, excretion) process, transporting, binding with receptor and intracellular signal transduction. Pharmacogenetic and pharmacogenomic studies have successfully identified genetic variants that contribute to this interindividual variability in antipsychotics response. In addition, epigenetic factors such as methylation of DNA and regulation by miRNA have also been reported to play an important role in the complex interactions between the multiple genes and environmental factors which influence individual drug response phenotypes in patients. In this review, we will focus on the latest research on polymorphisms of candidate genes that code for drug metabolic enzymes (CYP2D6, CYP1A2, CYP3A4, etc.), drug transporters (mainly ABCB1) and neurotransmitter receptors (dopamine receptors and serotonin receptors, etc.). We also discuss the genome-wide pharmacogenomic study of schizophrenia and review the current state of knowledge on epigenetics and potential clinical applications.

Dynamic network of transcription and pathway crosstalk to reveal molecular mechanism of MGd-treated human lung cancer cells.

Recent research has revealed various molecular markers in lung cancer. However, the organizational principles underlying their genetic regulatory networks still await investigation. Here we performed Network Component Analysis (NCA) and Pathway Crosstalk Analysis (PCA) to construct a regulatory network in human lung cancer (A549) cells which were treated with 50 uM motexafin gadolinium (MGd), a metal cation-containing chemotherapeutic drug for 4, 12, and 24 hours. We identified a set of key TFs, known target genes for these TFs, and signaling pathways involved in regulatory networks. Our work showed that putative interactions between these TFs (such as ESR1/Sp1, E2F1/Sp1, c-MYC-ESR, Smad3/c-Myc, and NFKB1/RELA), between TFs and their target genes (such as BMP41/Est1, TSC2/Myc, APE1/Sp1/p53, RARA/HOXA1, and SP1/USF2), and between signaling pathways (such as PPAR signaling pathway and Adipocytokines signaling pathway). These results will provide insights into the regulatory mechanism of MGd-treated human lung cancer cells.

Genetic polymorphisms in CYP2E1: association with schizophrenia susceptibility and risperidone response in the Chinese Han population.

BACKGROUND: CYP2E1 is a member of the cytochrome P450 superfamily, which is involved in the metabolism and activation of both endobiotics and xenobiotics. The genetic polymorphisms of CYP2E1 gene (Chromosome 10q26.3, Accession Number NC_000010.10) are reported to be related to the development of several mental diseases and to be involved in the clinical efficacy of some psychiatric medications. We investigated the possible association of CYP2E1 polymorphisms with susceptibility to schizophrenia in the Chinese Han Population as well as the relationship with response to risperidone in schizophrenia patients. METHODS: In a case-control study, we identified 11 polymorphisms in the 5' flanking region of CYP2E1 in 228 schizophrenia patients and 384 healthy controls of Chinese Han origin. From among the cases, we chose 130 patients who had undergone 8 weeks of risperidone monotherapy to examine the relationship between their response to risperidone and CYP2E1 polymorphisms. Clinical efficacy was assessed using the Brief Psychiatric Rating Scale (BPRS). RESULTS: Statistically significant differences in allele or genotype frequencies were found between cases and controls at rs8192766 (genotype p = 0.0048, permutation p = 0.0483) and rs2070673 (allele: p = 0.0018, permutation p = 0.0199, OR = 1.4528 95%CI = 1.1487-1.8374; genotype: p = 0.0020, permutation p = 0.0225). In addition, a GTCAC haplotype containing 5 SNPs (rs3813867, rs2031920, rs2031921, rs3813870 and rs2031922) was observed to be significantly associated with schizophrenia (p = 7.47E-12, permutation p<0.0001). However, no association was found between CYP2E1 polymorphisms/haplotypes and risperidone response. CONCLUSIONS: Our results suggest that CYP2E1 may be a potential risk gene for schizophrenia in the Chinese Han population. However, polymorphisms of the CYP2E1 gene may not contribute significantly to individual differences in the therapeutic efficacy of risperidone. Further studies in larger groups are warranted to confirm our results.

Quantitative assessment of the effect of LRRK2 exonic variants on the risk of Parkinson's disease: a meta-analysis.

Leucine-rich repeat kinase 2 (LRRK2, PARK8) gene has attracted considerable attention since the variants in this gene are recognized as the most common cause of Parkinson's disease (PD) so far. A number of association studies concerning variants of LRRK2 gene and PD susceptibility have been conducted in various populations. However, some results were inconclusive. To derive a more precise estimation of the relationship between LRRK2 and genetic risk of PD, we performed a comprehensive meta-analysis which included 27,363 cases and 29,741 controls from 61 published case-control studies. Totally, the effect of five LRRK2 variants all within the coding regions, i.e. G2019S, G2385R, R1628P, P755L and A419V, were evaluated in the meta-analysis using fixed effect model or random effects model if heterogeneity existed. There were genetic associations between four variants (G2019S, G2385R, R1628P and A419V) and increased PD risk, while there was no evidence of statistically significant association between P755L and PD. Publication bias and heterogeneity were absent in most analyses. Within its limitations, this meta-analysis demonstrated that the G2019S, G2385R, R1628P and A419V variations are risk factors associated with increased PD susceptibility. However, these associations vary in different ethnicities.

MiR-140 is co-expressed with Wwp2-C transcript and activated by Sox9 to target Sp1 in maintaining the chondrocyte proliferation.

MiR-140 is a microRNA specially involved in chondrogenesis and osteoarthritis pathogenesis. However, its transcriptional regulation and target genes in cartilage development are not fully understood. Here we detected that miR-140 was uniquely expressed in chondrocyte and suppressed by Wnt/ß-catenin signalling. The miR-140 primary transcript was an intron-retained RNA co-expressed with Wwp2-C isoform, which was directly induced by Sox9 through binding to the intron 10 of Wwp2 gene. Knockdown of miR-140 in limb bud micromass cultures resulted in arrest of chondrogenic proliferation. Sp1, the activator of the cell cycle regulator p15(INK4b), was identified as a target of miR-140 in maintaining the chondrocyte proliferation. Collectively, our findings expand our understanding of the transcriptional regulation and the chondrogenic role of miR-140 in chondrogenesis.

A systematic genetic polymorphism analysis of the CYP2C9 gene in four different geographical Han populations in mainland China.

While many studies have been focused on CYP2C9*2 and *3 there was a lack of large full gene sequencing on CYP2C9, and this study was designed to fill this gap. We used direct sequencing to systematically screen genetic polymorphisms of the CYP2C9 gene including the 5' -flanking region (2kb), all exons and their adjoining intron regions and the 3' UTR in 400 unrelated healthy Chinese Han volunteers. A total of 27 different CYP2C9 polymorphisms were identified, 3 of which were novel, including one in intron 6, a synonymous variant (1137T>C, Tyr379Tyr), and a deletion mutation in the 3'UTR (1739-1740ATdel), which potentially influences the stability of CYP2C9 mRNA. We identified CYP2C9*1, *2, *3, *8, *11, and *31, of which alleles *8 was identified for the first time in Chinese population while *11 first in Asian. This is the first systematic screening of genetic polymorphisms of CYP2C9 in the Chinese Han population.

The PstI/RsaI and DraI polymorphisms of CYP2E1 and head and neck cancer risk: a meta-analysis based on 21 case-control studies.

BACKGROUND: CYP2E1 encodes a member of the cytochrome P450 superfamily of enzymes which play a central role in activating and detoxifying many carcinogens and endogenous compounds thought to be involved in the development of cancer. The PstI/RsaI and DraI polymorphism are two of the most commonly studied polymorphisms of the gene for their association with risk of head and neck cancer, but the results are conflicting. METHODS: We performed a meta-analysis using 21 eligible case-control studies with a total of 4,951 patients and 6,071 controls to summarize the data on the association between the CYP2E1 PstI/RsaI and DraI polymorphism and head and neck cancer risk, especially by interacting with smoking or alcohol. RESULTS: Compared with the wild genotype, the OR was 1.96 (95% CI: 1.33-2.90) for PstI/RsaI and 1.56 (95% CI: 1.06-2.27) for DraI polymorphism respectively. When stratified according to ethnicity, the OR increased in the Asians for both polymorphisms (OR = 2.04, 95% CI: 1.32-3.15 for PstI/RsaI; OR = 2.04, 95% CI: 1.27-3.29 for DraI), suggesting that the risk is more pronounced in Asians. CONCLUSION: Our meta-analysis suggests that individuals with the homozygote genotypes of PstI/RsaI or DraI polymorphism might be associated with an increased risk of head and neck cancer, especially in Asians.

Systematic polymorphism analysis of the CYP2D6 gene in four different geographical Han populations in mainland China.

In this study, we systematically screened the polymorphisms of the whole CYP2D6 gene in the populations of four different geographical locations in China, namely, Shanghai, Shantou, Shenyang, and Xi'an, using a sample of 100 subjects from each population. Forty-eight different polymorphisms were detected as well as 12 novel ones. One novel nonsynonymous SNP was detected, and one novel intronic SNP was revealed that might inactivate a cryptic donor site 392 nucleotides downstream of the exon 6 natural donor site. In addition, the frequencies of some polymorphisms and alleles demonstrated significant differences among the four populations. Linkage disequilibrium analysis and tag SNP selection were performed separately for each population. Haplotypes were analyzed within the selected tag SNPs. Tag SNP selection and haplotype distributions showed differences across the four populations. This is the first large-scale study to analyze polymorphisms systematically across the whole CYP2D6 gene in the Chinese Han population.