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ABSTRACT: Oral lichen planus (OLP) is a chronic mucocutaneous condition that affects the oral mucous membrane as well as skin. It is a chronic cell-mediated autoimmune condition where the T-cell-mediated immune response plays an important part in the pathogenesis by causing damage to basal keratinocytes in oral mucosa. Cytokine gene polymorphisms have an unquestionable role in the orchestration of the immune response, leading to different functional scenarios, which in turn influence the outcome of the disease establishment and evolution. The purpose of this study was to understand the role of these cytokine gene polymorphisms in the tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), and IL-6 genes with OLP in 101 individuals of Malayalam-speaking ethnicity from South India (Kerala). We further investigated the role of these polymorphisms in patients suffering from OLP with other comorbid factors. Genotyping was carried out by polymerase chain reaction-restriction fragment length polymorphism. The results demonstrate that the A allele in the TNF-α -308 polymorphism could play an important role in the susceptibility to OLP. IL-1β +3954 in OLP was associated with other comorbid factors in both allelic and genotypic combinations. However, when patients suffering from OLP were stratified to understand the involvement of other comorbid factors, we observed that the T and C alleles were independent risk factors for chronic periodontitits and diabetes mellitus. On the other hand, IL-6 -597 did not show any disease association with OLP in the study population. This study indicates that proinflammatory cytokines are an important factor in understanding the disease burden of OLP and their comorbid factors.
Journal of interferon & cytokine research: the official journal of the International Society for Interferon and Cytokine Research 05/2013; · 1.63 Impact Factor
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ABSTRACT: Aims: Trial and error mode of antipsychotic drugs in treatment of schizophrenia can result in symptom exacerbations, relapse and severe side effects, resulting in higher costs of treatment. P-glycoprotein (ABCB1) is known to regulate the concentration of antipsychotic drugs in brain. Variable expressivity based on polymorphism in the gene ABCB1 may reflect on the drug response and its relationship to dosage.
Materials & methods: All antipsychotic dosages administered to patients were converted to common chlorpromazine equivalents. Response to antipsychotics was based on 50% cutoff in Brief Psychiatric Rating Scale ratings after 1-year of follow-up. Using a case–control study design, ABCB1 polymorphisms were screened in 192 individuals grouped into responders and nonresponders.
Results: A strong allelic, genotypic and haplotypic association, was observed, which was predictive of good response to antipsychotics. Individuals carrying the favorable homozygous genotypes of rs1045642 and rs2032582 displayed better response with increased dosage while those carrying risk genotype manifested refractoriness on increased dosage.
Conclusion: The study suggests that a priori knowledge of ABCB1 genotypes can provide a significant input into evaluating the patient’s response and minimizing redundant dosing and refractoriness.
Pharmacogenomics 07/2012; 13(10):1119-1127. · 3.97 Impact Factor
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Pharmacogenomics 07/2012; 13(10):1119-1127. · 3.97 Impact Factor
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ABSTRACT: The conventional practice of using trial and error mode to select antipsychotic drugs in treatment of schizophrenia can result in symptom exacerbations, relapse and severe side effects, resulting in higher costs of treatment. P-glycoprotein (ABCB1) is known to regulate the concentration of antipsychotic drugs in the brain. Variable expressivity based on polymorphism in the gene ABCB1 may reflect on the drug response and its relationship to dosage.
All antipsychotic dosages administered to patients were converted to common chlorpromazine equivalents. Response to antipsychotics was based on 50% cutoff in Brief Psychiatric Rating Scale ratings after 1-year of follow-up. Using a case-control study design, ABCB1 polymorphisms were screened in 192 individuals grouped into responders and nonresponders.
A strong allelic, genotypic and haplotypic association, was observed, which was predictive of good response to antipsychotics. Individuals carrying the favorable homozygous genotypes of rs1045642 and rs2032582 displayed better response with increased dosage while those carrying risk genotype manifested refractoriness on increased dosage.
The study suggests that a priori knowledge of ABCB1 genotypes can provide a significant input into evaluating the patient's response to medication, and minimizing redundant dosing and refractoriness.
Pharmacogenomics 07/2012; 13(10):1119-27. · 3.97 Impact Factor
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ABSTRACT: We compared the allele and genotype frequencies of SCN1A SNP rs3812718 between patients with MTLE-HS of south Indian ancestry with and without febrile seizures (FS) and with ethnically matched controls. While we observed no significant difference in allele and genotype frequencies of rs3812718 between MTLE-HS patients with and without FS, A allele and AA genotype were overrepresented in MTLE-HS patients when compared to controls. We conclude that in the population studied, although rs3812718 polymorphism increases the susceptibility to MTLE-HS, this is not by increasing the susceptibility to FS.
Epilepsy research 05/2012; 101(3):288-92. · 2.48 Impact Factor
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ABSTRACT: Objective: To investigate the role of single nucleotide polymorphisms (SNPs) in ATP-binding cassette family gene, ABCB1 in predicting the postoperative seizure recurrence in antiepileptic drug (AED)-resistant temporal lobe epilepsy (TLE) patients from Southern India.
Background Even though several electro-clinical and imaging characteristics could predict postoperative seizure outcome in patients with drug-resistant TLE patients, none of them have consistently been shown to be associated with the outcome. The genetic factors can play a critical role in attaining postoperative seizure freedom, and if identified, they could serve as biological markers of immense clinical importance. Increased P-glycoprotein expression in the temporal lobe has been shown to be associated with AED resistance and seizure recurrence after surgery. We hypothesized that genetic variation in ABCB1 could influence postoperative seizure outcome in TLE patients.
Design/Methods: We assembled 200 patients, who had undergone anterior temporal lobectomy (ATL) for AED-resistant TLE and had been followed up for 5 years after surgery. We genotyped seven SNPs in the ABCB1 gene using PCR-RFLP and compared the distribution of SNPs between patients who were seizure-free and those who had seizure recurrence.
Results: Genotypic frequencies were in Hardy-Weinberg equilibrium with exception to rs1045642 in seizure-free group. There was no significant difference in allele and genotype frequencies of the SNPs in ABCB1 gene between patients who were seizure-free and those who had seizure recurrence.
Conclusions: Even though studies have suggested that P-glycoprotein expression in temporal lobe may be associated with postoperative seizure recurrence, we could not find any association in genotypic level with the studied SNPs, so as to predict seizure recurrence.
http://www.neurology.org/cgi/content/meeting_abstract/78/1_MeetingAbstracts/P05.079
Neurology 04/2012; · 8.31 Impact Factor
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Moinak Banerjee
Indian Journal of Human Genetics 05/2011; 17 Suppl 1:S1-3.
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ABSTRACT: Multidrug resistance is one of the most serious problems in the treatment of epilepsy that is likely to have a complex genetic and acquired basis. Various experimental data support the hypothesis that over-expression of antiepileptic drug (AED) transporters may play a pivotal role in drug resistance. Hyyt 6however, key questions concerning their functionality remain unanswered. The idea that P-glycoprotein, encoded by the ABCB1 gene, might mediate at least part of the drug resistance was met with both enthusiasm and skepticism. As in oncology, initial optimism has been clouded subsequently by conflicting results. The first study reporting a positive association between genetic variation in the P-glycoprotein and multidrug-resistant epilepsy was published in 2003. Since then, several other genetic association studies have attempted to verify this result. However, taken overall, the role of P-glycoprotein in drug resistance in epilepsy still remains uncertain. We intend to critically review the inherent problems associated with epilepsy pharmacogenetic studies in general and with ABCB1 polymorphisms studies in particular. The lessons learnt from the ABCB1 studies can help us to guide future association genetics studies to investigate AED resistance, and thereby taking us closer to the cherished dream of personalized AED therapy.
Indian Journal of Human Genetics 05/2011; 17 Suppl 1:S12-21.
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ABSTRACT: Mesial temporal lobe epilepsy (MTLE) is the most common medically refractory epilepsy syndrome in adults, and hippocampal sclerosis (HS) is the most frequently encountered lesion in patients with MTLE. Premature accumulation of corpora amylacea (CoA), which plays an important role in the sequestration of toxic cellular metabolites, is found in the hippocampus of 50-60% of the patients who undergo surgery for medically refractory MTLE-HS. However, the etiopathogenesis and clinical importance of this phenomenon are still uncertain. The ABCB1 gene product P-glycoprotein (P-gp) plays a prominent role as an antiapoptotic factor in addition to its efflux transporter function. ABCB1 polymorphism has been found to be associated with downregulation of P-gp expression. We hypothesized that a similar polymorphism will be found in patients with CoA deposition, as the polymorphism predisposes the hippocampal neuronal and glial cells to seizure-induced excitotoxic damage and CoA formation ensues as a buffer response.
We compared five single nucleotide polymorphisms in the ABCB1 gene Ex06+139C/T (rs1202168), Ex 12 C1236T (rs1128503), Ex 17-76T/A (rs1922242), Ex 21 G2677T/A (rs2032582), Ex26 C3435T (rs1045642) among 46 MTLE-HS patients of south Indian ancestry with and without CoA accumulation.
We found that subjects carrying the Ex-76T/A polymorphism (TA genotype) had a five-times higher risk of developing CoA accumulation than subjects without this genotype (Odds ratio 5.0, 95% confidence intervals 1.34-18.55; P = 0.016).
We speculate that rs1922242 polymorphism results in the downregulation of P-gp function, which predisposes the hippocampal cells to seizure-induced apoptosis, and CoA gets accumulated as a buffer response.
Indian Journal of Human Genetics 05/2011; 17 Suppl 1:S41-7.
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ABSTRACT: Aneurysmal subarachnoid hemorrhage (aSAH) has a mortality rate as high as 50%. The prevalence of intracranial aneurysms from various parts of India varies from 0.75 to 10.3%, with higher numbers of cases being diagnosed due to the increasing age of the population and improvements in imaging techniques. However, little is known about the attributable risk factors of aSAH in the Indian population.
Using a case-control study we estimated the risk of factors such as hypertension, cigarette smoking, alcohol consumption, diabetes mellitus and family history of aSAH in a South Indian population. The population-attributable risk (PAR) of smoking, hypertension and alcohol use was estimated for the South Indian as well as for the general Indian population.
Our results showed that cigarette smoking (OR, 3.59; p < 0.001) and a history of hypertension (OR, 2.98; p < 0.001) were significant risk factors associated with aSAH. When patients were classified by gender, it was observed that being a smoker and having hypertension increased the risk for aSAH by nearly fourfold in men. Among women, hypertension and older age were significant risk factors. The PAR estimates indicated that smoking (OR, 3.59; 95% CI, 2.13-6.06) and hypertension (OR, 2.98; 95% CI, 1.73-5.12) are significant risk factors.
Hypertension and smoking may be causal risk factors which might also modify the effect of genetic factors that could increase susceptibility to aSAH in the Indian population. Since these risk factors are amenable to effective modification, our findings will be useful for a gender-specific management of aSAH.
Cerebrovascular Diseases 02/2010; 29(3):268-74. · 2.72 Impact Factor
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ABSTRACT: Interleukin (IL)-1beta gene polymorphisms are considered a potential risk factor for periodontal disease. The aim of this study is to identify the association of IL-1beta gene polymorphisms with chronic periodontitis and aggressive periodontitis in a Malayalam-speaking Dravidian population from South India.
The case-control study consisted of 43 patients with chronic periodontitis and 54 patients with aggressive periodontitis as cases, and the control group consisted of 101 healthy subjects. All subjects were genotyped for IL-1beta +3954, -511, and -31 loci by polymerase chain reaction amplification followed by restriction enzyme digestion and gel electrophoresis. Genotype, allele, and haplotype analyses were done.
Analyses for allele and genotypes showed a high frequency of the C allele and CC genotype for single nucleotide polymorphism IL-1beta +3954 in the group with chronic periodontitis and no difference for patients with aggressive periodontitis compared to controls (P <0.05). Haplotype analysis showed that IL-1beta -31 and -511 were in strong linkage disequilibrium in all groups. The IL-1beta -31 allele T was in linkage with allele T of IL-1beta +3954 in the control group.
In the Malayalam-speaking Dravidian population, allele C of IL-1beta +3954 appeared to be an important risk factor for chronic periodontitis. The IL-1beta -31 allele T was in linkage with allele T of IL-1beta +3954 in the control group. No gene polymorphisms were found in patients with aggressive periodontitis. More studies with a larger sample size involving the entire cluster of the IL-1beta gene are necessary to determine the exact role of IL-1beta gene polymorphisms in periodontal disease.
Journal of Periodontology 01/2010; 81(1):62-9. · 2.60 Impact Factor
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ABSTRACT: Serotonin (5-hydroxytryptamine (5-HT)) transporter (SLC6A4) is known to influence mood, emotion, cognition and efficacy of antidepressants, particularly that of selective serotonin reuptake inhibitors. Atypical antipsychotics exert their effects partially through serotinergic systems, and hence, variation in 5-HT uptake may affect antipsychotic action mediated through the serotinergic system. Therefore, investigating the role of SLC6A4 as a risk factor for developing schizophrenia and treatment response had been a point of concern for many investigators, but with variable outcome. In this study, we examined the genetic roles of five polymorphisms of SLC6A4, including those of the widely studied 44 base pair variable number of tandem repeat (VNTR) in the promoter region of SLC6A4 (the serotonin transporter gene-linked polymorphic region: 5HTTLPR) and a VNTR polymorphism (STin2) in the second intron, in schizophrenia and its influence on the severity of symptoms in a South Indian population from Kerala, comprising 586 individuals. We detected significant allelic and genotypic associations with rs2066713 (both allelic and genotypic P-value <0.001), 5HTTLPR (allelic P-value=0.008 and genotypic P-value=0.03) and STin2 polymorphisms (allelic P-value=0.001 and genotypic P-value=0.002). A haplotype linking these three risk alleles, 5HTTLPR/S-rs2066713/C-STin2/12-repeat (P-value=0.0059), was also significantly associated with disease in our population. Patients with STin2 12-repeat homozygotes showed a greater severity of blunted effect symptom. These results suggest a strong role of SLC6A4 in schizophrenia, possibly with a specific behavioral endophenotype in a South Indian population.
Journal of Human Genetics 09/2009; 54(9):538-42. · 2.57 Impact Factor
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ABSTRACT: The transmembrane P-glycoprotein that functions as a drug-efflux transporter coded by ATP-binding cassette, subfamily B, member 1/Multidrug Resistance 1 (ABCB1/MDR1) gene is considered relevant to drug absorption and elimination, with access to the central nervous system. Effects of three ABCB1 single nucleotide polymorphisms (SNPs) in genotypic and haplotypic combination have been evaluated in a south Indian population for risk of pediatric medically refractory epilepsy. The study included age and sex matched medically refractory (N=113) cases and drug responsive epilepsy patients (N=129) as controls, belonging to the same ethnic population recruited from a tertiary referral centre, of Karnataka, Southern India. The genotype frequencies of SNPs c.1236C>T, c.2677G>T/A, and c.3435C>T were determined from genomic DNA of the cases and controls by PCR- RFLP and confirmatory DNA sequencing. 256 normal population samples of the same ethnicity were genotyped for the three loci to check for population stratification. Results indicate that there was no statistically significant difference between allele and genotype frequencies of refractory and drug responsive epilepsy patients. The predicted haplotype frequencies of the three polymorphisms did not show significant difference between cases and controls. The results confirm earlier observations on absence of association of ABCB1 polymorphisms with medically refractory epilepsy.
Drug Metabolism and Pharmacokinetics 02/2009; 24(3):255-60. · 2.32 Impact Factor
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ABSTRACT: Endothelial nitric oxide synthase (eNOS) gene polymorphisms have been implicated as predisposing genetic factors that can predict aneurysmal subarachnoid hemorrhage (aSAH), but with controversial results from different populations. Using a case-control study design, we tested the hypothesis whether variants in eNOS gene can increase risk of aSAH among South Indian patients, either independently, or by interacting with other risk factors of the disease. We enrolled 122 patients, along with 224 ethnically matched controls. We screened the intron-4 27-bp VNTR, the promoter T-786C and the exon-7 G894T SNPs in the eNOS gene. We found marked interethnic differences in the genotype distribution of eNOS variants when comparing the South Indian population with the reported frequencies from Caucasian and Japanese populations. Genotype distributions in control and patient populations were found to be in Hardy-Weinberg equilibrium. In patients, the allele, genotype and estimated haplotype frequencies did not differ significantly from the controls. Multiple logistic regression indicated hypertension and smoking as risk factors for the disease, however the risk alleles did not have any interaction with these risk factors. Although the eNOS polymorphisms were not found to be a likely risk factor for aSAH, the role of factors such as ethnicity, gender, smoking and hypertension should be evaluated cautiously to understand the genotype to phenotype conversion.
Disease markers 02/2008; 24(6):333-9. · 1.64 Impact Factor
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ABSTRACT: Background: Schizophrenia is a debilitating psychiatric disorder.
Nearly 6–7 million Indians suffer from this disorder. Research over
the last three decades has led to a wide variety of loosely collected
findings on genetic associations, neurochemical alterations, neuroimaging
deficits, cognitive deficits and a host of environmental and social
factors. From a therapeutic standpoint also the gains are modest. The
main focus of treatment still remains symptomatic control of psychotic
symptoms. Thus, the challenge is to provide a model for understanding
schizophrenia that allows one to cut across several of the
relevant dimensions and to move the therapeutics beyond just the
symptomatic control of psychosis. We know that social and cultural
traits do impact mental abilities. Various ecological and linguistic
barriers further appends to cultural diversity, which can influence
differential mental capabilities among different population groups in
presenting a disease.
Methods: In present study the role of socio-cultural relationship in
causing schizophrenia and the genotype phenotype correlations of
drug metabolizing enzymes, drug receptor and transporter polymorphisms
has been evaluated. Genotype phenotype correlation has also
been evaluated in relation to the symptomatic and medication history
of the patients using BPRS-E rating scores.
Results:We observe distinct shift in the LD patterns in different genes
of responder and non-responder groups. 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.
Conclusions: Our study suggests that population genetic parameters in
relation to socio-cultural factors may help in precise understanding of
genotype phenotype correlations in theranostics of schizophrenia.
Schizophrenia Research 02/2008; 98(3):199. · 4.75 Impact Factor
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ABSTRACT: Schizophrenia is a debilitating psychiatric disorder with a prevalence
of 2.2 per 1,000 adults in India. Disturbances in dopamine and
serotonin neurotransmitter is hypothesized to cause schizophrenia.
Polymorphisms in these genes can affect individuals response to
therapeutic agents. Understanding the pharmacogenetics of thesegenes have implications for therapeutic effects, abusepotential and
side effects of these drugs. In this study we examined the role of
19SNPs in Dopamine receptor D3 (DRD3), Dopamine receptor D4
(DRD4), Dopamine transporter (SLC6A3), Serotonin receptor 1B
(HTR1B), Serotonin receptor 6 (HTR6), Serotonin receptor 2A
(HTR2A), Serotonin receptor 3B (HTR3B) and Serotonin transporter
(SLC6A4) genes in schizophrenia; in the presentation of symptom
and antipsychotic treatment response in South Indian population.
Subjects included 243 schizophrenic patients and 243 ethnically and
age-matched controls. Patients were assessed using BPRS. Clinical
improvement was assessed by percent impovement after 1 year follow-
up. H–WE allele and genotype frequency was calculated with
COCAPHASE and LD pattern with Haploview. DRD4rs936461 is
associated with of disorganized behavior (p = 0.0153), conceptual
disorganization (0.134), motor retardation (0.012), tension
(p = 0.022) and uncooperativeness (p = 0.01). Association was
observed with DRD4rs936460 with somatic concern (p = 0.05) and
DATrs2652510 with motor retardation. 5HT2AS1438 and 102T/C
polymorphism influenced self neglect (p = 0.02), blunted effect
(0.05) and motor retardation (p = 0.04). SLC6A4 polymorphism was
significantly associated with schizophrenia. 12rpt allele and 12/12
genotype was over represented in cases when compared to controls
(p = 0.002). DRD4rs936460 T allele was over represented in cases
(p = 0.07). A significant difference in haplotype frequency was noted
in the serotonin transporter gene with C-12 haplotype over represented
in cases (p = 0.009). No significant association of the
polymorphisms with antipsychotic treatment response was observed.
This suggests that neurotransmitter receptor and transporter gene
polymorphisms screened alone is not involved in complex antipsychotic
drug response profile in this population. The study reports
significant association with SLC6A4. The difference in the presentation
of symptoms in schizophrenic patients throughout the world,
influenced by the sociocultural factors like ethnicity could prove vital
in solving the present chaos in the field of psychiatric genetics.
Genomic Medicine 01/2008; 2:349-400.
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ABSTRACT: Alterations 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.
We 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.
H313HTT 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.
Based 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.
Behavioral and Brain Functions 02/2007; 3:34. · 2.13 Impact Factor
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ABSTRACT: The genes encoding the human leukocyte antigens (HLAs; major histocompatibility complex [MHC]) have been considered candidate markers for periodontitis because they are involved in regulating immune responses. Several studies have examined this association, and despite the inconclusive results, the antigens HLA-A9 and HLA-B15 have been found to be consistently associated with the destructive forms of periodontitis in many populations. Ethnic factors are considered to be a major variable for evaluating the predisposition to the disease. The purpose of the present study was to: 1) assess the association of HLA-A*9 and HLA-B*15 with generalized aggressive periodontitis (GAgP) and 2) evaluate the role of these genetic risk factors in influencing the severity of GAgP in a South Indian population.
Forty GAgP patients (cases) and 80 periodontally and systemically healthy subjects (controls) participated in this study. HLA-A*9 and HLA-B*15 typing was carried out using the polymerase chain reaction with sequence specific primers (PCR-SSP)-based molecular method.
HLA-B*15 was a significant risk factor for GAgP and was positively correlated with the disease severity, whereas HLA-A*9 had no association with the disease. The haplotype of HLA-A*9:B*15 did not impart any additional risk for GAgP compared to that imparted by HLA-B*15 alone.
To our knowledge, this is the first report on HLA-B*15 association with GAgP in an Indian population. The finding of HLA-B*15 as a risk factor may have potential use in the future management of GAgP. The precise disease-causing mechanism of this HLA disease association and whether this association is "causal" or "casual" need to be evaluated further.
Journal of Periodontology 01/2007; 77(12):1954-63. · 2.60 Impact Factor
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Journal of Genetics and Molecular biology. 01/2007;
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ABSTRACT: Abstract
Background
Alterations 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.
Methods
We 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.
Results
H313HTT 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.
Conclusion
Based 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.
Behavioral and Brain Functions. 01/2007;
