Department Of Human Genetics And Molecular Medicine
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Item Variants in KCNQ1 increase type II diabetes susceptibility in South Asians: A study of 3,310 subjects from India and the US(2011) Been, L.F.; Ralhan, S.; Wander, G.S.; Mehra, N.K.; Singh, J.; Mulvihill, J.J.; Aston, C.E.; Sanghera, D.K.Background: Polymorphisms in intron 15 of potassium voltage-gated channel, KQT-like subfamily member 1 (KCNQ1) gene have been associated with type II diabetes (T2D) in Japanese genome-wide association studies (GWAS). More recently a meta-analysis of European GWAS has detected a new independent signal associated with T2D in intron 11 of the KCNQ1 gene. The purpose of this investigation is to examine the role of these variants with T2D in populations of Asian Indian descent from India and the US.Methods: We examined the association between four variants in the KCNQ1 gene with T2D and related quantitative traits in a total of 3,310 Asian Indian participants from two different cohorts comprising 2,431 individuals of the Punjabi case-control cohort from the Sikh Diabetes Study and 879 migrant Asian Indians living in the US.Results: Our data confirmed the association of a new signal at the KCNQ1 locus (rs231362) with T2D showing an allelic odds ratio (OR) of 1.24 95%CI [1.08-1.43], p = 0.002 in the Punjabi cohort. A moderate association with T2D was also seen for rs2237895 in the Punjabi (OR 1.14; p = 0.036) and combined cohorts (meta-analysis OR 1.14; p = 0.018). Three-site haplotype analysis of rs231362, rs2237892, rs2237895 exhibited considerably stronger evidence of association of the GCC haplotype with T2D showing OR of 1.24 95%CI [1.00-1.53], p = 0.001, permutation p = 8 ? 10-4in combined cohorts. The 'C' risk allele carriers of rs2237895 had significantly reduced measures of HOMA-B in the US cohort (p = 0.008) as well as in combined cohort in meta-analysis (p = 0.009).Conclusions: Our investigation has confirmed that the variation within the KCNQ1 locus confers a significant risk to T2D among Asian Indians. Haplotype analysis further suggested that the T2D risk associated with KCNQ1 SNPs may be derived from 'G' allele of rs231362 and 'C' allele of rs2237895 and this appears to be mediated through ? cell function. ? 2011 Been et al; licensee BioMed Central Ltd.Item Shared and unique common genetic determinants between pediatric and adult celiac disease(BioMed Central Ltd., 2016) Senapati, S.; Sood, A.; Midha, V.; Sood, N.; Sharma, S.; Kumar, L.; Thelma, B.K.Background: Based on age of presentation, celiac disease (CD) is categorised as pediatric CD and adult CD. It however remains unclear if these are genetically and/or phenotypically distinct disorders or just different spectrum of the same disease. We therefore explored the common genetic components underlying pediatric and adult CD in a well characterized north Indian cohort. Methods: A retrospective analysis of children (n = 531) and adult (n = 871) patients with CD between January 2001 and December 2010 was done. The database included basic demographic characteristics, clinical presentations, associated diseases and complications, if any. The genotype dataset was acquired for children (n = 217) and adult CD patients (n = 340) and controls (n = 736) using Immunochip. Association analysis was performed using logistic regression model to identify susceptibility genetic variants. Results: The predominant form of CD was classical CD in both pediatric and adult CD groups. There was remarkable similarity between pediatric and adult CD except for quantitative differences between the two groups such as female preponderance, non-classical presentation, co-occurrence of other autoimmune diseases being more common amongst adult CD. Notably, same HLA-DQ2 and -DQ8 haplotypes were established as the major risk factors in both types of CD. In addition, a few suggestively associated (p < 5 ? 10-4) non-HLA markers were identified of which only ANK3 (rs4948256-A; rs10994257-T) was found to be shared and explain risk for ?45 % of CD patients with HLA allele. Discussion: Overall phenotypic similarity between pediatric and adult CD groups can be explained by contribution of same HLA risk alleles. Different non-HLA genes/loci with minor risk seem to play crucial role in disease onset and extra intestinal manifestation of CD. None of the non-HLA risk variants reached genome-wide significance, however most of them were shown to have functional implication to disease pathogenesis. Functional relevance of our findings needs to be investigated to address clinical heterogeneity of CD. Conclusions: This present study is the first comparative study based on common genetic markers to suggest that CD in pediatric age group and in adults are the spectrum of the same disease with novel and shared genetic risk determinants. Follow-up fine mapping studies with larger study cohorts are warranted for further genetic investigation. ? 2016 The Author(s).Item Oxidative stress in the development of genetic generalised epilepsy: An observational study in southern Indian population(Journal of Clinical and Diagnostic Research, 2017) Prasad, D.K.V.; Satyanarayana, U.; Shaheen, U.; Surya Prabha, T.; Munshi, A.Introduction: Oxidative stress resulting from excessive generation of Reactive Oxygen Species (ROS) plays a significant role in neurodegeneration associated with seizures/epilepsy. Aim: To evaluate oxidative stress markers and antioxidant enzymes in Genetic Generalised Epilepsy (GGE) and to know the extent of oxidative stress induced by Anti-Epileptic Drugs (AEDs) with the time duration of treatment. Materials and Methods: In this case-control study, 310 GGE patients (male:female=203:107), who were on AED treatment (n=235) and 75 untreated patients (male:female=49:26) along with 310 age and sex matched healthy controls were recruited. Oxidative stress markers such as Nitric Oxide (NO), Malondialdehyde (MDA) and antioxidant enzyme activities namely Superoxide Dismutase (SOD), Glutathione Peroxidase (GPx) and Catalase (CAT) were measured spectrophotometrically. Results: Significantly higher levels of serum NO, MDA and low levels of plasma Total Antioxidant Capacity (TAC) were found in patients as compared to controls (p<0.001) whereas erythrocyte SOD, CAT and GPx activities were found to be significantly low in patients when compared to the control group (p<0.001). Statistically significant higher levels of NO, MDA and lower levels of SOD, CAT and TAC were observed in patients subgroup, who were on AEDs for more than >5 years compared to other groups (? 1 year and 1-? 5 years) (p=0.02, p=0.01, p=0.001, p=0.01 and p=0.05 respectively). Further, significant increase in the levels of NO, MDA and decreased activities of SOD, CAT were found in treated patients compared to untreated patients (p<0.05) denoting that additional oxidative stress induced by AEDs which results in seizure recurrence and drug intractability. Conclusion: Our study demonstrated that GGE patients have additional oxidative stress due to AEDs and decreased antioxidant enzyme activities causing an imbalance between oxidant and antioxidant status, which might contribute to the pathogenesis of GGE. ? 2017, Journal of Clinical and Diagnostic Research. All rights reserved.Item Interleukin 1ß (+3954, -511 and -31) polymorphism in chronic periodontitis patients from North India(Informa Healthcare, 2015) Amirisetty, Ramesh; Patel, Ritu Prabha; Das, Satrupa; Saraf, Jitendra; Jyothy, Akka; Munshi, AnjanaObjective. Several studies have implicated the role of interleukin-1 in various chronic diseases including periodontitis. The present study was carried out with an aim to evaluate the role of interleukin 1? polymorphisms, namely +3954C/T, -511C/T and -31T/C, in the development of chronic periodontitis. Materials and methods. Twenty-nine chronic periodontitis patients and 31 healthy controls of North Indian origin from Chhattisgarh were recruited for the study. The genotypes for the three variants were determined using the PCR-RFLP technique and the strength of association between genotypes and periodontitis was determined by odds ratio with 95% confidence interval (CI) and chi-square analysis. Results. Analysis for the +3954 allelic and genotypic frequencies of the polymorphism revealed a significant difference in the CT genotype between periodontitits patients and controls (p = 0.03). A significant difference was also observed in the allelic frequencies between the two groups (p = 0.02). For the -511 site, TT genotype revealed a significant association with the disease (p = 0.01). A significant association was also found following the co-dominant model (p = 0.007). However, the -31 polymorphism revealed no significant difference between patients and controls. Conclusions. In conclusion, the present study suggests a strong association of the TT genotype of -511 and CT genotype of +3954 variant of interleukin 1? with chronic periodontitis. However, the -31 variant did not show a significant association with the disease. ? Informa Healthcare.Item Genome-wide association study identifies a novel locus contributing to type 2 diabetes susceptibility in Sikhs of Punjabi origin from India(American Diabetes Association Inc., 2013) Saxena, R.; Saleheen, D.; Been, L.F.; Garavito, M.L.; Braun, T.; Bjonnes, A.; Young, R.; Ho, W.K.; Rasheed, A.; Frossard, P.; Sim, X.; Hassanali, N.; Radha, V.; Chidambaram, M.; Liju, S.; Rees, S.D.; Ng, D.P.-K.; Wong, T.-Y.; Yamauchi, T.; Hara, K.; Tanaka, Y.; Hirose, H.; McCarthy, M.I.; Morris, A.P.; Basit, A.; Barnett, A.H.; Katulanda, P.; Matthews, D.; Mohan, V.; Wander, G.S.; Singh, J.R.; Mehra, N.K.; Ralhan, S.; Kamboh, M.I.; Mulvihill, J.J.; Maegawa, H.; Tobe, K.; Maeda, S.; Cho, Y.S.; TaWe performed a genome-wide association study (GWAS) and a multistage meta-analysis of type 2 diabetes (T2D) in Punjabi Sikhs from India. Our discovery GWAS in 1,616 individuals (842 case subjects) was followed by in silico replication of the top 513 independent single nucleotide polymorphisms (SNPs) (P < 10-3) in Punjabi Sikhs (n = 2,819; 801 case subjects). We further replicated 66 SNPs (P < 10-4) through genotyping in a Punjabi Sikh sample (n = 2,894; 1,711 case subjects). On combined meta-analysis in Sikh populations (n = 7,329; 3,354 case subjects), we identified a novel locus in association with T2D at 13q12 represented by a directly genotyped intronic SNP (rs9552911, P = 1.82 ? 10-8) in the SGCG gene. Next, we undertook in silico replication (stage 2b) of the top 513 signals (P < 10-3) in 29,157 non-Sikh South Asians (10,971 case subjects) and de novo genotyping of up to 31 top signals (P < 10-4) in 10,817 South Asians (5,157 case subjects) (stage 3b). In combined South Asian meta-analysis, we observed six suggestive associations (P < 10-5 to < 10-7), including SNPs at HMG1L1/CTCFL, PLXNA4, SCAP, and chr5p11. Further evaluation of 31 top SNPs in 33,707 East Asians (16,746 case subjects) (stage 3c) and 47,117 Europeans (8,130 case subjects) (stage 3d), and joint meta-analysis of 128,127 individuals (44,358 case subjects) from 27 multiethnic studies, did not reveal any additional loci nor was there any evidence of replication for the new variant. Our findings provide new evidence on the presence of a population-specific signal in relation to T2D, which may provide additional insights into T2D pathogenesis. ? 2013 by the American Diabetes Association.Item Association of the genetic variants of insulin receptor substrate 1 (IRS-1) with type 2 diabetes mellitus in a Saudi population(Humana Press Inc., 2014) Alharbi, Khalid Khalaf; Khan, Imran Ali; Munshi, Anjana; Alharbi, Fawiziah Khalaf; Al-Sheikh, Yazeed; Alnbaheen, May SalemType 2 diabetes mellitus (T2DM) is a chronic degenerative disease, phenotypically and genetically heterogeneous, characterized by high levels of glucose and metabolic complications. Insulin receptor substrate 1 (IRS-1) plays a key role in the insulin-stimulated signal transduction pathway. A glycine-to-arginine substitution at codon 972 (G972R) (rs1801278) in the IRS-1 gene has been associated with impaired insulin action. Another SNP rs2943641 in the IRS-1 gene has been found to be associated with T2DM and insulin resistance in genome-wide association studies. The aim of the present study was to evaluate whether rs1801278 and rs2943641 are associated with increased risk of T2DM in the Saudi population. The study included 376 T2DM cases and 380 healthy controls. Genomic DNA was isolated using a commercially available kit supplied by Norgen Biotech Corp. Genotyping was performed by PCR and RFLP analysis. There was a significant difference in the genotypic distribution as well as allelic frequency between the T2DM cases and controls in case of both the polymorphisms for rs1801278 (1.752, 95?% CI 1.002?3.121; p?=?0.04), and for rs2943641 (OR?=?1.482, 95?% CI 1.176?1.867; p?=?0.001). In conclusion, both the (rs1801278 and rs2943641) polymorphisms are associated with T2DM in the Saudi population. ? 2014, Springer Science+Business Media New York.Item A low frequency variant within the GWAS locus of MTNR1B affects fasting glucose concentrations: Genetic risk is modulated by obesity(2012) Been, L.F.; Hatfield, J.L.; Shankar, A.; Aston, C.E.; Ralhan, S.; Wander, G.S.; Mehra, N.K.; Singh, J.R.; Mulvihill, J.J.; Sanghera, D.K.Two common variants (rs1387153, rs10830963) in MTNR1B have been reported to have independent effects on fasting blood glucose (FBG) levels with increased risk to type 2 diabetes (T2D) in recent genome-wide association studies (GWAS). In this investigation, we report the association of these two variants, and an additional variant (rs1374645) within the GWAS locus of MTNR1B with FBG, 2h glucose, insulin resistance (HOMA IR), ?-cell function (HOMA B), and T2D in our sample of Asian Sikhs from India. Our cohort comprised 2222 subjects [1201 T2D, 1021 controls]. None of these SNPs was associated with T2D in this cohort. Our data also could not confirm association of rs1387153 and rs10830963 with FBG phenotype. However, upon stratifying data according to body mass index (BMI) (low ? 25 kg/m2 and high > 25 kg/m2) in normoglycemic subjects (n = 1021), the rs1374645 revealed a strong association with low FBG levels in low BMI group (? = -0.073, p = 0.002, Bonferroni p = 0.01) compared to the high BMI group (? = 0.015, p = 0.50). We also detected a strong evidence of interaction between rs1374645 and BMI with respect to FBG levels (p = 0.002). Our data provide new information about the significant impact of another MTNR1B variant on FBG levels that appears to be modulated by BMI. Future confirmation on independent datasets and functional studies will be required to define the role of this variant in fasting glucose variation. ? 2011.Item Association of serum homocysteine and hs-CRP with idiopathic generalised epilepsy and duration of antiepileptic drug therapy(Journal of Clinical and Diagnostic Research, 2018) Prasad, D.K.V.; Satyanarayana, U.; Prabhakararao, T.S.; Surya Prabha, T.; Munshi, A.Introduction: Several human and experimental studies have revealed that chronic inflammation may play a vital role in neurodegenerative processes including epilepsy. There is accumulating evidence that inflammatory processes affect the pathophysiology of different epilepsy types. Aim: To assess the concentrations of Homocysteine (Hcy) and High Sensitivity C-Reactive Protein (hs-CRP) in Idiopathic Generalised Epilepsy (IGE) patients and their association with IGE and duration of the Anti Epileptic Drugs (AEDs). Materials and Methods: This case-control study consisted of 100 IGE patients (50 tonic?clonic, 15 absence and 35 myoclonic seizures) and equal number of healthy controls. Hcy levels were assayed by Centaur XP using ADVIA centaur Hcy; whereas hs-CRP levels by ELISA method using commercially available kits. Results: The Hcy and hs-CRP levels were significantly increased in both the patient groups (<18 years and >18 years). Significant difference in the levels of Hcy was observed between different epilepsy types of <18 years patients (p=0.01), whereas hs-CRP in >18 years patients (<0.05). Significantly elevated levels of hs-CRP were noticed in non-responders group compared to responders (<0.05). There was a positive correlation between hs-CRP and Hcy (R2=0.44 and p<0.001) and significant difference in the levels of Hcy and hs-CRP was observed in the patient subgroups who were on AEDs for different time periods (?1 year, 1- ?5 years and >5 years) (p=0.002 and p<0.05 respectively) since, AEDs can induce oxidative stress. Conclusion: Hyperhomocysteinaemia (Hyper-Hcy) can induce as well as promote oxidative stress and hence, it can be implicated in neurodegeneration in epilepsy. Elevated levels of hs-CRP in non-responders may be resulted by the contribution of inflammatory pathways in ictogenesis in epileptic tissue, causing intractable epilepsy. ? 2018, Journal of Clinical and Diagnostic Research. All rights reserved.Item Innate Immune Responses and Antioxidant/Oxidant Imbalance Are Major Determinants of Human Chagas Disease(Public Library of Science, 2013) Dhiman, Monisha; Coronado, Yun A.; Vallejo, Cecillia K.; Peterson, John R.; Ejilemele, Adetoun; Nunez, Sonia; Zago, Maria Paola; Spratt, Hiedi; Garg, Nisha JainBackground:We investigated the pathological and diagnostic role of selected markers of inflammation, oxidant/antioxidant status, and cellular injury in human Chagas disease.Methods:Seropositive/chagasic subjects characterized as clinically-symptomatic or clinically-asymptomatic (n = 116), seronegative/cardiac subjects (n = 102), and seronegative/healthy subjects (n = 45) were analyzed for peripheral blood biomarkers.Results:Seropositive/chagasic subjects exhibited an increase in sera or plasma levels of myeloperoxidase (MPO, 2.8-fold), advanced oxidation protein products (AOPP, 56%), nitrite (5.7-fold), lipid peroxides (LPO, 12-17-fold) and malondialdehyde (MDA, 4-6-fold); and a decline in superoxide dismutase (SOD, 52%) and glutathione (GSH, 75%) contents. Correlation analysis identified a significant (p<0.001) linear relationship between inflammatory markers (AOPP/nitrite: r = 0.877), inflammation and antioxidant/oxidant status (AOPP/glutathione peroxidase (GPX): r = 0.902, AOPP/GSH: r = 0.806, Nitrite/GPX: 0.773, Nitrite/LPO: 0.805, MDA/MPO: 0.718), and antioxidant/oxidant levels (GPX/MDA: r = 0.768) in chagasic subjects. Of these, MPO, LPO and nitrite biomarkers were highly specific and sensitive for distinguishing seropositive/chagasic subjects from seronegative/healthy controls (p<0.001, training and fitting AUC/ROC >0.95). The MPO (r = 0.664) and LPO (r = 0.841) levels were also correlated with clinical disease state in chagasic subjects (p<0.001). Seronegative/cardiac subjects exhibited up to 77% decline in SOD, 3-5-fold increase in LPO and glutamate pyruvate transaminase (GPT) levels, and statistically insignificant change in MPO, AOPP, MDA, GPX, GSH, and creatine kinase (CK) levels.Conclusions:The interlinked effects of innate immune responses and antioxidant/oxidant imbalance are major determinants of human Chagas disease. The MPO, LPO and nitrite are excellent biomarkers for diagnosing seropositive/chagasic subjects, and MPO and LPO levels have potential utility in identifying clinical severity of Chagas disease. ? 2013 Dhiman et al.