Project description:To predict differentially expressed miRNAs between monosomy 3 and disomy 3, and to associate these miRNAs with the clinico-pathological parameters in South Asian Indian population with uveal melanoma (UM). The study consists of six uveal melanoma primary tumour tissues of South Asian-Indian population. These six tumours have been screened for chromosome 3 aberration using Chromogenic in-situ hybridisation (CISH). Thus, sample under the study includes, three each of monosomy 3 and disomy 3. The miRNA profiling was carried out from the tumor sections of formalin-fixed paraffin embedded eyeball samples. miRNA expression profile was obtained in monosomy 3 and disomy 3 samples, analysed by unsupervised analysis (Principal Component Analysis) and supervised analysis (Significance analysis of microarray). The select up-regulated and candidate miRNAs associated with monosomy 3 uveal melanoma tumors were validated further with qRT-PCR (n=86). Thus, this study indicates the role of miRNAs in UM tumor progression and their implication in predetermining the liver metastasis.
Project description:Dysregulation of the glutamate transporters EAAT1 and EAAT2 and their isoforms have been implicated in schizophrenia. EAAT1 and EAAT2 expression has been studied in different brain regions but the prevalence of astrocytic glutamate transporter expression masks the more subtle changes in excitatory amino acid transporters (EAATs) isoforms in neurons in the cortex. Using laser capture microdissection, pyramidal neurons were cut from the anterior cingulate cortex of postmortem schizophrenia (n = 20) and control (n = 20) subjects. The messenger RNA (mRNA) levels of EAAT1, EAAT2 and the splice variants EAAT1 exon9skipping, EAAT2 exon9skipping and EAAT2b were analyzed by real time PCR (RT-PCR) in an enriched population of neurons. Region-level expression of these transcripts was measured in postmortem schizophrenia (n = 25) and controls (n = 25). The relationship between selected EAAT polymorphisms and EAAT splice variant expression was also explored. Anterior cingulate cortex pyramidal cell expression of EAAT2b mRNA was increased (P < 0.001; 67%) in schizophrenia subjects compared with controls. There was no significant change in other EAAT variants. EAAT2 exon9skipping mRNA was increased (P < 0.05; 38%) at region level in the anterior cingulate cortex with no significant change in other EAAT variants at region level. EAAT2 single-nucleotide polymorphisms were significantly associated with changes in EAAT2 isoform expression. Haloperidol decanoate-treated animals, acting as controls for possible antipsychotic effects, did not have significantly altered neuronal EAAT2b mRNA levels. The novel finding that EAAT2b levels are increased in populations of anterior cingulate cortex pyramidal cells further demonstrates a role for neuronal glutamate transporter splice variant expression in schizophrenia.
Project description:To predict differentially expressed miRNAs between monosomy 3 and disomy 3, and to associate these miRNAs with the clinico-pathological parameters in South Asian Indian population with uveal melanoma (UM). The study consists of six uveal melanoma primary tumour tissues of South Asian-Indian population. These six tumours have been screened for chromosome 3 aberration using Chromogenic in-situ hybridisation (CISH). Thus, sample under the study includes, three each of monosomy 3 and disomy 3. The miRNA profiling was carried out from the tumor sections of formalin-fixed paraffin embedded eyeball samples. miRNA expression profile was obtained in monosomy 3 and disomy 3 samples, analysed by unsupervised analysis (Principal Component Analysis) and supervised analysis (Significance analysis of microarray). The select up-regulated and candidate miRNAs associated with monosomy 3 uveal melanoma tumors were validated further with qRT-PCR (n=86). Thus, this study indicates the role of miRNAs in UM tumor progression and their implication in predetermining the liver metastasis. The study consists of six uveal melanoma primary tumour tissues of South Asian-Indian population. These six tumours have been screened for chromosome 3 abberation using chromogenic in-situ hybridisation (CISH). Thus, samples under the study includes three each of monosomy 3 and disomy 3. The miRNA profiling were carried out from the tumor sections of formalin-fixed paraffin embedded eyeball samples. The up-regulated miRNAs associated with monosomy 3 uveal melanoma tumors were short listed and the candidate miRNAs were validated further with qRT-PCR. Agilent one-color experiment, Organism: Homo sapiens, Agilent Human miRNA 8x15k Arrays AMADID: 021827 [Agilent miRNA labeling reagent and Hybridization Kit Cat # 5190-0408]
Project description:This paper depicts the first report from an Indian population on the association between the variant Arg399Gln of XRCC1 locus in the DNA repair system and schizophrenia, the debilitating disease that affects 1% of the world population. Genotypic analysis of a total of 523 subjects (260 patients and 263 controls) revealed an overwhelming presence of Gln399Gln in the case subjects against the controls (P < 0.0068), indicating significant level of association of this nsSNP with schizophrenia; the Gln399 allele frequency was also perceptibly more in cases than in controls (p < 0.003; OR = 1.448). The results of the genotypic studies were further validated using pathogenicity and stability prediction analysis employing computational tools [I-Mutant Suite, iStable, PolyPhen2, SNAP, and PROVEAN], with a view toassess the magnitude of deleteriousness of the mutation. The pathogenicity analysis reveals that the nsSNP could be deleterious inasmuch as it could affect the functionality of the gene, and interfere with protein function. Molecular dynamics simulation of 60ns was performed using GROMACS to analyse structural change due to a mutation (Arg399Gln) that was never examined before. RMSD, RMSF, hydrogen bonds, radius of gyration and SASA analysis showedthe existence of asignificant difference between the native and the mutant protein. The present study gives astrong indication that the XRCC1 locus deserves serious attention, as it could be a potential candidatecontributing to the etio-pathogenesis of the disease.
Project description:BackgroundAlterations in the dopamine transmission and receptor density are hypothesized in the pathophysiology of schizophrenia but ethnic disparities are reported to exist in disease association and therapeutic response to psychotropic medication. Antipsychotics have higher binding affinity to D2 subtype of dopamine receptor. DRD2 Cys311, TaqIB1 and TaqIA1 variants are considered to have either reduced affinity for dopamine and hypo-dopaminergic activity.MethodsWe examined the role of Taq1B, Taq1D, S311C, H313H and Taq1A polymorphisms of DRD2 gene in schizophrenia and antipsychotic treatment response in 213 patients and 196 controls from a homogenous South Indian population. A more detailed genotype phenotype association analysis was carried out to understand the disease in terms of its socio-cultural factors.ResultsH313HTT genotype was found to be associated with schizophrenia (P = 0.004) while TaqIB1B1 genotype was significantly associated with higher psychopathology score. When treatment response was considered H313HCC, TaqIA2A2 and Taq1D1D1 had higher mean improvement scores. TaqID1D1 and H313HTT genotype were found to be significantly higher in responders than in nonresponder group. Distinct shift in the LD patterns of responder and non-responder group was observed. Certain symptoms were characteristic of our patient population. Following medication the scores and presentation of these symptoms tend to vary in the responder and non-responder groups.ConclusionBased on genotype phenotype correlations it can be suggested that certain polymorphisms can be defined for their critical functions in disease and their role in treatment response in South Indian population. The present study suggests that in addition to ethnic bias, socio-cultural factors should also be considered while evaluating genotype phenotype correlations, in association and treatment response to complex disorders like schizophrenia.
Project description:BACKGROUND AND OBJECTIVES: Serotonin transporter polymorphisms, 5-HTTVNTR and 5-HTTLPR, have been found to be associated with obsessive-compulsive disorder (OCD) and particularly with neurotic characteristics. In the present study we looked for an association between OCD and these polymorphisms in OCD patients and controls of south Indian origin. METHODS: 5-HTTVNTR and 5-HTTLPR/rs25531 were genotyped in 93 OCD patients and 92 healthy controls. The allelic distribution and genotype frequency in cases and controls were compared using chi square test. In order to test for the effects of genotype on heterogeneity of the illness, linear regression analysis was undertaken for co-morbid depression status and YBOCS score (severity index). RESULTS: There was no significant association with the 5-HTTVNTR or the 5-HTTLPR polymorphism. No significant association of OCD with the 5-HTTLPR genotype was found even on inclusion of the rs25531 locus, which is part of the transcription factor binding site as reported in earlier studies. However, severity of the illness showed a modest association with the dominant model. INTERPRETATION AND CONCLUSIONS: Our data show that genetic variation in the SLC6A4 gene regulatory region may not have a significant effect on OCD in the present population. Further replication in a large and independent cohort with an equal number of female subjects would help to ascertain if the absence of association in this cohort is due to the nullifying effect of the larger proportion of male subjects in our sample population. The marginal effect of the 5-HTTLPR (A/G) genotype obtained on linear regression with disease severity is suggestive of a potential role for this locus in the disease process.
Project description:BackgroundGenetic variations represented as single nucleotide polymorphisms (SNPs) vary across the world population. This genetic polymorphism (such as SNPs) plays an important role in pharmacogenomics. SNPs that affects cellular metabolism, by altering the enzyme activity, have an important role in therapeutic outcome. Allele frequencies in number of clinically relevant SNPs within south Indian populations are not yet known. Hence, we genotyped randomly selected unrelated south Indian subjects from different locations of south India representing the heterogeneous ethnic background of the population.Materials and methodsCommon variants of MTHFD1, TYMS, SHMT1, MTR, MTRR, CBS and SULT1A1 gene polymorphisms were screened from healthy unrelated south Indian volunteers. Genotypes were determined using RFLP analysis of polymerase chain reaction-amplified products and confirmed by DNA sequencing. Chi-square test was performed to test for deviation from the Hardy-Weinberg equilibrium for each locus.ResultsGene allele frequency for several polymorphisms in our study differed significantly between the populations of other nations reported for several of the SNPs. These results demonstrate that the populations in different geographic regions may have widely varying genetic allele frequencies for clinically relevant SNPs.ConclusionThe present study reports, for the first time, the frequency distribution of MTHFD1, TYMS, SHMT1, MTR, MTRR, CBS and SULTIA1 gene polymorphisms in a south Indian population. Population-specific genetic polymorphism studies will help in practicing pharmacogenomic principles in the clinics.
Project description:Glutamate cycling is critically important for neurotransmission, and may be altered in schizophrenia. The excitatory amino acid transporters (EAATs) facilitate the reuptake of glutamate from the synaptic cleft and have a key role in glutamate cycling. We hypothesized that expression of the EAATs and the EAAT regulating proteins ARHGEF11, JWA, G-protein suppressor pathway 1 (GPS1), and KIAA0302 are altered in the brain in schizophrenia. To test this, we measured expression of EAAT1, EAAT2, EAAT3, and EAAT interacting proteins in postmortem tissue from the dorsolateral prefrontal and anterior cingulate cortex of patients with schizophrenia and a comparison group using in situ hybridization and Western blot analysis. We found increased EAAT1 transcripts and decreased protein expression, increased EAAT3 transcripts and protein, and elevated protein expression of both GPS1 and KIAA0302 protein. We did not find any changes in expression of EAAT2. These data indicate that proteins involved in glutamate reuptake and cycling are altered in the cortex in schizophrenia, and may provide potential targets for future treatment strategies.
Project description:Genomic studies revealed two main components in the genetic architecture of schizophrenia, one constituted by common variants determining a distributed polygenic effect and one represented by a large number of heterogeneous rare and highly disruptive mutations. These gene modifications often affect neural transmission and different studies proved an involvement of metabotropic glutamate receptors in schizophrenia phenotype. Through the combination of literature information with genomic data from public repositories, we analyzed the current knowledge on the involvement of genetic variations of the human metabotropic glutamate receptors in schizophrenia and related endophenotypes. Despite the analysis did not reveal a definitive connection, different suggestive associations have been identified and in particular a relevant role has emerged for GRM3 in affecting specific schizophrenia endophenotypes. This supports the hypothesis that these receptors are directly involved in schizophrenia disorder.
Project description:BackgroundTo examine the relationship between single-nucleotide polymorphisms (SNPs) in interleukin (IL) genes and keratitis and its clinical manifestations.MethodsSNPs in IL1B, IL6, CXCL8, IL10, and IL12B were analysed. Differences in frequencies of alleles, genotypes and haplotypes between cases and controls as well as associations between SNPs and clinical variables were calculated by χ2 tests with odds ratios.ResultsThe minor homologous genotype in IL1B rs16944 (p = 0.036; odds ratio (OR) = 2.063, 95% confidence interval (CI): 1.048-4.061) and CXCL8 rs4073 (p = 0.041; OR = 0.463, 95% CI: 0.224-0.956) and the heterologous genotypes in IL6 rs1800795 (p = 0.046; OR = 0.563, 95% CI: 0.326-0.972) and IL12B rs2569254 (p = 0.0446; OR = 0.557, 95% CI: 0.314-0.989) or rs730691 (p = 0.0051; OR = 0.451, 95% CI: 0.260-0.784) were associated with keratitis. The minor genotype of rs16944 was associated with severe infection (p = 0.046). The heterologous genotype in rs2569254 was associated with hospital admission, photophobia, and mode of contact lens wear (p ≤ 0.041). The heterologous genotype in rs730691 was associated with blurred vision, discharge, anterior chamber reaction, and mode of wear (p ≤ 0.047).ConclusionsThis study demonstrates that SNPs in IL1B and CXCL8 are associated with risk of developing keratitis. The study also found relationships between SNPs and clinical measures of keratitis. The potential for ethnic differences in frequency of SNPs and their association with keratitis should be followed up using different populations.