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1.
Pediatr Diabetes ; 22(1): 47-51, 2021 02.
Artículo en Inglés | MEDLINE | ID: mdl-32558116

RESUMEN

OBJECTIVES: To study the prevalence and clinical characteristics of islet antibody-negative (idiopathic) type 1 diabetes mellitus (T1DM) among Indian children and adolescents at the time of diagnosis of illness. METHODS: In a hospital-based cross-sectional study, we studied 110 patients with T1DM aged ≤18 years. This included 61 patients with duration of diabetes ≤2 weeks (mean ± SD age of onset 9.9 ± 4.4 years) and 49 patients with duration 2 to 12 weeks. Antibodies against GAD65 (GADA), IA-2 (IA-2A) and zinc transporter 8 (ZnT8A), detected by radio-binding assay, were measured in all patients. Insulin autoantibody (IAA) was measured only in subjects with duration ≤2 weeks, using a competitive radio-binding assay. RESULTS: The prevalence of GADA, IA-2A, and ZnT8A was 53%, 34%, and 29% respectively, while IAA (measured in 61 patients) was detected in 31%. All four antibodies were absent in 17 of 61 (28%) patients. The prevalence of islet antibody-negative patients was similar among both sexes and in children with onset younger and older than 10 years. ZnT8A was the only antibody detected in four patients, and its measurement resulted in 6% reduction in islet antibody-negative patients. Patients with idiopathic T1DM did not differ in their clinical features or fasting plasma C-peptide at the onset and after follow-up of 1 year. Compared with idiopathic T1DM, antibody-positive patients had an increased allele frequency of HLA DRB1*0301 (46% vs 14%, OR = 5.10 [confidence interval = 1.61-16.16], P = .003). CONCLUSION: Nearly 30% of Indian patients were negative for all islet antibodies at the onset of T1DM. Patients with idiopathic T1DM had similar clinical features to antibody-positive subjects.


Asunto(s)
Autoanticuerpos/análisis , Diabetes Mellitus Tipo 1/epidemiología , Islotes Pancreáticos/inmunología , Adolescente , Niño , Estudios Transversales , Diabetes Mellitus Tipo 1/inmunología , Femenino , Humanos , India/epidemiología , Masculino , Prevalencia
2.
Clin Immunol ; 216: 108449, 2020 07.
Artículo en Inglés | MEDLINE | ID: mdl-32376502

RESUMEN

Killer cell immunoglobulin-like receptors (KIRs), act as the regulators for the cytolytic activity of natural killer and certain T cells by interacting with the HLA class I ligands. KIRs have been shown to contribute to the pathogenesis of several autoimmune diseases. However, their specific roles are still not very clear. Autoimmune diseases are multifactorial in nature, highlighting the influence of both genetic and environmental factors. The innate immune response plays an important role in autoimmunity as it alters the self-glycans that mimic molecular patterns found on different intracellular pathogens. Natural killer (NK) cells have an important position in the innate immune response. NK cell receptors are encoded by the leukocyte receptor complex located on the chromosome 19q13.4 and lectin-like receptors on chromosome 12p13. This review focuses on the role of KIRs and their relationship with different autoimmune diseases.


Asunto(s)
Enfermedades Autoinmunes/inmunología , Células Asesinas Naturales/inmunología , Receptores KIR/inmunología , Receptores de Células Asesinas Naturales/inmunología , Animales , Humanos , Inmunidad Innata/inmunología , Ligandos , Linfocitos T/inmunología
3.
Pediatr Blood Cancer ; 65(1)2018 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-28766851

RESUMEN

BACKGROUND: Treatment-related toxicity and mortality are not uncommon during maintenance chemotherapy for childhood acute lymphoblastic leukemia (ALL), especially in the low- and middle-income countries (LMIC). Undernutrition and micronutrient deficiencies are commonly seen in children from LMICs undergoing treatment for ALL. The present study examines the prevalence and clinical implications of folate deficiency in north Indian children with ALL during the maintenance phase of treatment in view of prolonged antifolate treatment and high population prevalence of folate deficiency. PROCEDURES: Pre-cycle folate levels/deficiency as well as weight for age z-score and serum albumin level were determined and correlated with complications of treatment and mortality encountered during the maintenance phase of treatment. RESULTS: Twenty-nine of 52 children enrolled in the study had folate deficiency at some point during maintenance chemotherapy. Neutropenia (18 of 29 vs. 4 of 23; P = 0.002), thrombocytopenia (17 of 29 vs. 4 of 23; P = 0.005), febrile neutropenia (17 of 29 vs. 4 of 23; P = 0.005), and need for chemotherapy dose reduction (20 of 29 vs. 7 of 21; P = 0.01) were more common in folate-deficient children. Maintenance deaths were higher (8 of 29 vs. 1 of 23; P = 0.03) and survival lower (P = 0.02) in deficient children. In multivariate analysis, hypoalbuminemia (P = 0.02) and folate deficiency (P = 0.01) were associated with febrile neutropenia, and folate deficiency with maintenance deaths (P = 0.03). CONCLUSIONS: Folate deficiency was associated with treatment-related complications and adverse outcome in our patients. The risks and benefits of folate supplementation in deficient children during maintenance chemotherapy need to be explored with properly designed randomized studies in similar settings.


Asunto(s)
Deficiencia de Ácido Fólico/mortalidad , Quimioterapia de Mantención , Leucemia-Linfoma Linfoblástico de Células Precursoras/tratamiento farmacológico , Leucemia-Linfoma Linfoblástico de Células Precursoras/mortalidad , Niño , Preescolar , Supervivencia sin Enfermedad , Neutropenia Febril/sangre , Neutropenia Febril/tratamiento farmacológico , Neutropenia Febril/mortalidad , Femenino , Deficiencia de Ácido Fólico/sangre , Humanos , India/epidemiología , Masculino , Leucemia-Linfoma Linfoblástico de Células Precursoras/sangre , Prevalencia , Tasa de Supervivencia
4.
Indian J Med Res ; 146(2): 163-174, 2017 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-29265017

RESUMEN

Folate has been studied in relation to many diseases, especially cancer. Although it has been postulated to exert a dual effect on development of cancer, its role remains to be clearly defined. Its effect on cancer is the result of gene-nutrient interaction between the genes in folate metabolic pathway and dietary folate availability; mutations in genes of folate metabolism have been shown to alter individual susceptibility to certain childhood cancers as well as response to cancer chemotherapy. Although mandatory fortification of food items with folate has been initiated in some countries, many countries are yet to adopt this due to concerns about undesired adverse effects of high folate levels on health, especially cancer. However, initial reports suggest that folate fortification has led to reduction in incidence of certain childhood cancers such as neuroblastoma, wilms tumour and leukaemias. Despite studies showing folate depletion during antifolate chemotherapy and higher toxicity of chemotherapy in folate-depleted individuals, folate supplementation during cancer chemotherapy is not routinely recommended. Studies investigating the precise effect of folate supplementation during chemotherapy on both short- and long-term outcomes of cancer are needed to arrive at a consensus guideline.


Asunto(s)
Ácido Fólico/metabolismo , Neoplasias/dietoterapia , Neoplasias/tratamiento farmacológico , Neoplasias/metabolismo , Antineoplásicos/efectos adversos , Antineoplásicos/uso terapéutico , Carbono/metabolismo , Niño , Suplementos Dietéticos , Ácido Fólico/genética , Humanos , Mutación , Neoplasias/patología
5.
J Hum Genet ; 61(12): 1035-1041, 2016 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-27488439

RESUMEN

Co-stimulatory CD28 and transcription factor NFKB1 genes are considered as a crucial player in the determination of inflammatory responses; genetic variability in these may modulate the risk for idiopathic recurrent miscarriages (IRM). We investigated the association of functional variants of CD28 (rs3116496 T/C) and NFKB1 (rs28362491 ins/del and rs696 A/G) with IRM cases. We recruited 200 IRM women with a history of at least three consecutive pregnancy losses before 20th week of pregnancy and 300 fertile control women. Determination of CD28 (rs3116496 T/C) and NFKB1 (rs28362491 ins/del and rs696 A/G) gene variants were based on the polymerase chain reaction pursued by restriction fragment length polymorphism analysis and validated with Sanger sequencing. Single marker analysis and multifactor dimensionality reduction (MDR) model used to predict the IRM risk. We observed nearly three- to twofold increased risk in single marker analysis for minor homozygous genotypes of rs3116496 T/C, rs28362491 ins/del and rs696 A/G tag-SNPs in IRM cases, suggesting the risk association. In MDR analysis, we observed 10.5-fold augmented risk among IRM women in three-SNP model (rs3116496 T/C, rs28362491 ins/del and rs696 A/G). The eQTL mapping analyses was performed to strengthen the results of our study. The eQTL mapping analysis revealed that the variations in CD28 and NFKB1 gene content might affect the abundance of transcripts of CD28 and Family with sequence similarity 177 member A1 (FAM177A1) genes, respectively. These results suggest that CD28 and NFKB1 gene variants may be associated with increased risks to IRM.


Asunto(s)
Aborto Habitual/genética , Antígenos CD28/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Variación Genética , Subunidad p50 de NF-kappa B/genética , Adulto , Alelos , Estudios de Casos y Controles , Mapeo Cromosómico , Epistasis Genética , Femenino , Genotipo , Humanos , Oportunidad Relativa , Embarazo , Sitios de Carácter Cuantitativo , Adulto Joven
6.
Nephrology (Carlton) ; 21(7): 592-600, 2016 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-26421528

RESUMEN

AIM: Involvement of pro-inflammatory genes has been correlated with basic kidney diseases and end stage renal disease (ESRD). However, results at odds were often noted from such independent association studies. This study proposes a genome wide analysis approach to predict ESRD risk associated genes. METHODS: We included 42 single nucleotide polymorphisms (SNPs) showing association among north Indian ESRD cases and controls. ESRD cases comprised chronic glomerulonephritis (CGN), chronic interstitial nephritis (CIN), hypertension (HTN) and autosomal dominant polycystic kidney disease (ADPKD). Genotyping data obtained from our prior published reports were compared with Genome-Wide Association Studies (GWAS) SNPs retrieved from HapMap and GWASCentral databases using R-statistical package SNPAssoc. Linkage disequilibrium (LD), gene-gene interaction, classification and regression tree (CART) and pathway analysis were carried out in the present study supplemented with IL-6 and TNF-α levels estimation using enzyme linked immunosorbent assay (ELISA). RESULTS: Comparison of genotyping data with GWAS SNPs revealed significant associations for interleukin (IL)1-RN, IL-6, MTHFR, tumour necrosis factor-α (TNF-α) and CCR3 genes with ESRD. Nine SNPs were commonly associated with CGN, CIN, HTN, ADPKD and ESRD. LD (D = 0.9) and gene-gene interaction (P = 0.0002) analyses revealed significant associations for IL-6 and TNF-α genes. In a consistent manner, CART analysis and functional analysis servers predict predisposing effects for TNF-α and IL-6 with ESRD. Finally, higher body circulating levels were observed for mutant TNF-α and IL-6 alleles among ESRD. CONCLUSION: The study indicates significance for IL-6 and TNF-α gene with basic kidney diseases and ESRD. Extensive statistical tests, pathway analysis and functional assays also reflect attenuated level of significance for these SNPs. In future these may be brought from bench side to clinical practice as diagnostic biomarkers upon external and prospective replication and confirmation among other cohorts.


Asunto(s)
Mediadores de Inflamación , Interleucina-6/genética , Fallo Renal Crónico/genética , Mutación , Polimorfismo de Nucleótido Simple , Factor de Necrosis Tumoral alfa/genética , Estudios de Casos y Controles , Biología Computacional , Análisis Mutacional de ADN , Bases de Datos Genéticas , Ensayo de Inmunoadsorción Enzimática , Femenino , Marcadores Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Humanos , India/epidemiología , Mediadores de Inflamación/sangre , Interleucina-6/sangre , Fallo Renal Crónico/sangre , Fallo Renal Crónico/diagnóstico , Fallo Renal Crónico/epidemiología , Desequilibrio de Ligamiento , Masculino , Fenotipo , Reacción en Cadena de la Polimerasa , Factores de Riesgo , Factor de Necrosis Tumoral alfa/sangre
7.
Pharmacogenet Genomics ; 25(1): 19-29, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25356901

RESUMEN

BACKGROUND: The role of CTLA4 gene polymorphisms in T-cell-mediated immunity in association with human cytomegalovirus (HCMV) infection after transplantation is poorly understood. In the present study, we have made an attempt to investigate the impact of CTLA4 single nucleotide polymorphisms (SNPs) (rs231775, rs5742909, rs11571317, rs16840252, rs4553808, rs3087243) and dinucleotide (AT)n repeat polymorphism on the incidence of symptomatic HCMV infection (disease) among 270 renal allograft recipients. MATERIALS AND METHODS: Genotyping of CTLA4 SNPs was performed by a PCR, followed by a restriction fragment length polymorphism assay. The detection of the dinucleotide (AT)n repeat polymorphism was carried out by PCR-polyacrylamide gel electrophoresis. RESULTS: An almost three-fold increased risk was observed for the incidence of symptomatic HCMV infection in mutant genotype carriers of rs231775 and rs3087243 SNPs under additive and recessive models, respectively. The mutant haplotype carriers of six studied SNPs (rs231775, rs5742909, rs11571317, rs16840252, rs4553808 and rs3087243) showed an almost two-fold higher risk for symptomatic HCMV cases, whereas wild-type haplotype combinations of these six SNPs showed a protective effect. Subsequently, no correlation was observed in the promoter region SNPs of CTLA4, namely, rs5742909, rs11571317, rs16840252 and rs4553808 in symptomatic HCMV cases at the genotypic/allelic level. Survival analysis showed that the mutant genotypes of rs231775 and rs3087243 SNPs were associated with the lowest HCMV disease-free survival compared with heterozygous and wild genotypes. The crude and adjusted hazard ratios showed an almost three-fold and 2.5-fold increased risk in univariate and multivariate Cox regression models, respectively, for HCMV disease-free survival against mutant genotypes of rs231775 and rs3087243 SNPs. CTLA4 dinucleotide (AT)n repeat analysis showed that the smaller allele (102 bp) was associated with a protective effect, whereas the longer (110 and 116 bp) alleles showed a susceptible effect for symptomatic HCMV cases. CONCLUSION: These results suggested that CTLA4 variants might be involved in the clinical manifestation of HCMV diseases.


Asunto(s)
Antígeno CTLA-4/genética , Infecciones por Citomegalovirus/genética , Rechazo de Injerto/genética , Trasplante de Riñón/efectos adversos , Adulto , Citomegalovirus/genética , Citomegalovirus/inmunología , Infecciones por Citomegalovirus/inmunología , Infecciones por Citomegalovirus/virología , Supervivencia sin Enfermedad , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Rechazo de Injerto/patología , Humanos , Masculino , Persona de Mediana Edad
8.
Hum Genet ; 134(6): 637-47, 2015 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-25832481

RESUMEN

There is no indication from the previous mtDNA studies that west Eurasian-specific subclades have evolved within India and played a role in the spread of languages and the origins of the caste system. To address these issues, we have screened 14,198 individuals (4208 from this study) and analyzed 112 mitogenomes (41 new sequences) to trace west Eurasian maternal ancestry. This has led to the identification of two autochthonous subhaplogroups--HV14a1 and U1a1a4, which are likely to have originated in the Dravidian-speaking populations approximately 10.5-17.9 thousand years ago (kya). The carriers of these maternal lineages might have settled in South India during the time of the spread of the Dravidian language. In addition to this, we have identified several subsets of autochthonous U7 lineages, including U7a1, U7a2b, U7a3, U7a6, U7a7, and U7c, which seem to have originated particularly in the higher-ranked caste populations in relatively recent times (2.6-8.0 kya with an average of 5.7 kya). These lineages have provided crucial clues to the differentiation of the caste system that has occurred during the recent past and possibly, this might have been influenced by the Indo-Aryan migration. The remaining west Eurasian lineages observed in the higher-ranked caste groups, like the Brahmins, were found to cluster with populations who possibly arrived from west Asia during more recent times.


Asunto(s)
ADN Mitocondrial/genética , Lenguaje , Polimorfismo de Nucleótido Simple , Clase Social , Antropología Cultural , Femenino , Humanos , India , Masculino
9.
Reprod Biomed Online ; 30(1): 82-91, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-25457193

RESUMEN

The effect of HLA-G 5'-upstream regulatory region (URR) single nucleotide polymorphisms (SNP) in idiopathic recurrent spontaneous abortion (RSA) was evaluated. Parental genotype combination analysis and HLA-G expression at transcriptional level was evaluated for 5'URR SNP, which have shown increased risk for idiopathic RSA. If a fetus were aneuploid, attributing causation to a HLA-G 5'-URR SNP would be illogical; therefore couples with abnormal parental karyotypes and also those with abortus material that revealed chromosomal abnormalities were excluded. One hundred women who had experienced idiopathic RSA, along with their respective male partners and 100 pairs of control couples, were studied. HLA-G 5'-URR SNP were evaluated through sequencing. Quantitative polymerase chain reaction was used for HLA-G expression analysis. An increased risk for idiopathic RSA cases among women carriers of mutant genotypes of -1179G>A(rs1233335), -725C>G/T(rs915670) and -486A>C(rs114252012) SNP. The parental genotype combination analysis revealed a 3.5-fold increased risk for -1179G>A and 4.3-fold increased risk for -725C>G/T SNP among carriers of mutant parental genotypes in couples who have experienced idiopathic RSA. Down-regulation in HLA-G expression was seen at transcriptional level for -1179G>A and -725C>G/T SNPs in cases of idiopathic RSA. Transmission of a mutant allele from single carrier parents may, therefore, affect pregnancy outcome.


Asunto(s)
Aborto Habitual/genética , Antígenos HLA-G/genética , Polimorfismo de Nucleótido Simple , Adulto , Algoritmos , Alelos , Estudios de Casos y Controles , Exones , Femenino , Predisposición Genética a la Enfermedad , Genotipo , Haplotipos , Humanos , Desequilibrio de Ligamiento , Masculino , Embarazo , ARN Mensajero/metabolismo , Factores de Riesgo
10.
Pharmacogenet Genomics ; 24(9): 442-50, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-24978643

RESUMEN

BACKGROUND AND AIM: MicroRNAs are important molecules of the innate and adaptive immune system, which may play an important role in maintaining normal immune homeostasis. The aim of this study was to investigate the impact of MIR146A C>G (rs2910164), MIR149 T>C (rs2292832), MIR196A2 T>C (rs11614913), and MIR499A A>G (rs3746444) single nucleotide polymorphisms (SNPs) among end-stage renal disease (ESRD) and acute allograft rejection (AR) cases. MATERIALS AND METHODS: Genotyping of MicroRNA SNPs was performed using a PCR, followed by restriction fragment length polymorphism in 350 ESRD patients and 350 age-matched, sex-matched, and ethnically matched controls. RESULTS: We observed an increased risk of almost two-fold for ESRD and three-fold for AR cases under univariate and multivariate models for mutant genotypes of rs2910164, rs11614913, and rs3746444 SNPs. Subsequently, no susceptible/protective effect was observed for rs2292832 SNP with ESRD and AR cases. Interestingly, all the SNPs that were significant after multiple comparisons in ESRD and AR cases remained significant in the bootstrap analysis, providing internal validation to our initial observations. Survival analysis showed that the mutant genotypes of rs2910164, rs11614913, and rs3746444 SNPs were associated with the lowest overall survival compared with heterozygous and wild genotypes among renal allograft recipients. The crude and adjusted hazard ratios in univariate and multivariate Cox regression models showed an almost two-fold increased risk for overall survival against mutant genotypes of rs2910164, rs11614913, and rs3746444 SNPs in renal allograft recipients. CONCLUSION: These results suggest that the variants of MicroRNA SNPs, namely, rs2910164, rs11614913, and rs3746444, might be involved in susceptibility to ESRD and AR.


Asunto(s)
Rechazo de Injerto/genética , Fallo Renal Crónico/terapia , MicroARNs/genética , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Supervivencia de Injerto , Humanos , Fallo Renal Crónico/genética , Trasplante de Riñón , Masculino , Polimorfismo de Nucleótido Simple , Trasplante Homólogo , Resultado del Tratamiento , Población Blanca/genética
11.
J Hum Genet ; 59(9): 529-35, 2014 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-25102096

RESUMEN

Various studies on association of glutathione S-transferase (GST) polymorphisms and childhood acute lymphoblastic leukemia (ALL) have yielded conflicting results. We examined this association among north Indian children and conducted an updated meta-analysis to overcome sample size-related limitations. GSTM1, GSTP1 and GSTT1 genotypes in 100 children with ALL and 300 healthy controls were compared. GSTT1 null mutation (odds ratio (OR) 2.54, 95% confidence interval (CI) 1.50-4.32) and GSTP1 homozygous mutation (OR 3.13, 95%CI 1.48-6.59) were found to increase the risk of childhood ALL, while GSTM1 did not alter the risk. Meta-analysis included 22, 10 and 20 studies examining the association of childhood ALL with GSTM1, GSTP1 and GSTT1 genotypes, respectively. Only GSTM1 genotype (OR 1.29, 95%CI 1.10-1.62) was associated with increased risk in the overall analysis. However, both GSTM1 (OR 1.54, 95%CI 1.12-2.10) and GSTT1 (OR 1.63, 95%CI 1.32-1.99) null genotypes were associated with increased risk in Asian subjects. The risk of developing childhood ALL was not associated with GSTP1 genotype.


Asunto(s)
Gutatión-S-Transferasa pi/genética , Glutatión Transferasa/genética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Adolescente , Estudios de Casos y Controles , Niño , Preescolar , Femenino , Frecuencia de los Genes , Predisposición Genética a la Enfermedad/genética , Genotipo , Humanos , India , Lactante , Modelos Logísticos , Masculino , Mutación , Leucemia-Linfoma Linfoblástico de Células Precursoras/enzimología , Factores de Riesgo
12.
J Hum Genet ; 59(7): 397-404, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24919644

RESUMEN

Studies on the association of methylenetetrahydrofolate reductase (MTHFR) genotype in childhood acute lymphoblastic leukemia (ALL) have yielded conflicting results. The present study examines this association in north Indian children with ALL and includes an updated meta-analysis. MTHFR (677 and 1298) genotype of children with ALL and healthy adult controls were done by the PCR-restriction fragment length polymorphism (PCR-RFLP) method and were compared using various models of inheritance. A total of 150 patients and 300 controls were included. The 677T allele was found protective (odds ratio (OR) 0.21, 95% confidence interval (CI) 0.04-0.94), whereas 1298C allele led to an increase in risk (OR 4.44, 95% CI 2.19-8.99) of childhood ALL. Meta-analysis included 31 and 27 studies examining the association of 677 and 1298 genotypes, respectively. The 677 C -> T polymorphism was protective (OR 0.90, 95% CI 0.82-0.99). Protection was more pronounced in folate-sufficient populations as compared with those not covered by folate fortification guidelines. The 1298A->C polymorphism was associated with a marginal increase in risk (OR 1.19, 95% CI 1.01-1.40).


Asunto(s)
Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Polimorfismo Genético , Leucemia-Linfoma Linfoblástico de Células Precursoras/genética , Alelos , Estudios de Casos y Controles , Niño , Preescolar , Genotipo , Humanos , India , Oportunidad Relativa
13.
Arthritis Rheum ; 65(12): 3026-35, 2013 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-23918589

RESUMEN

OBJECTIVE: Genome-wide association studies (GWAS) and their subsequent meta-analyses have changed the landscape of genetics in rheumatoid arthritis (RA) by uncovering several novel genes. Such studies are heavily weighted by samples from Caucasian populations, but they explain only a small proportion of total heritability. Our previous studies in genetically distinct North Indian RA cohorts have demonstrated apparent allelic/genetic heterogeneity between North Indian and Western populations, warranting GWAS in non-European populations. We undertook this study to detect additional disease-associated loci that may be collectively important in the presence or absence of genes with a major effect. METHODS: High-quality genotypes for >600,000 single-nucleotide polymorphisms (SNPs) in 706 RA patients and 761 controls from North India were generated in the discovery stage. Twelve SNPs showing suggestive association (P < 5 × 10(-5)) were then tested in an independent cohort of 927 RA patients and 1,148 controls. Additional disease-associated loci were determined using support vector machine (SVM) analyses. Fine-mapping of novel loci was performed by using imputation. RESULTS: In addition to the expected association of the HLA locus with RA, we identified association with a novel intronic SNP of ARL15 (rs255758) on chromosome 5 (Pcombined = 6.57 × 10(-6); odds ratio 1.42). Genotype-phenotype correlation by assaying adiponectin levels demonstrated the functional significance of this novel gene in disease pathogenesis. SVM analysis confirmed this association along with that of a few more replication stage genes. CONCLUSION: In this first GWAS of RA among North Indians, ARL15 emerged as a novel genetic risk factor in addition to the classic HLA locus, which suggests that population-specific genetic loci as well as those shared between Asian and European populations contribute to RA etiology. Furthermore, our study reveals the potential of machine learning methods in unraveling gene-gene interactions using GWAS data.


Asunto(s)
Factores de Ribosilacion-ADP/genética , Artritis Reumatoide/genética , Pueblo Asiatico/genética , Polimorfismo de Nucleótido Simple , Población Blanca/genética , Femenino , Frecuencia de los Genes , Sitios Genéticos , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Genotipo , Humanos , Masculino
14.
Ann Hum Biol ; 41(6): 540-7, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24689793

RESUMEN

BACKGROUND: Genes encoding KIR receptors are clustered in one of the most variable regions of the human genome. KIR gene frequencies vary in worldwide populations and reveal high probability of individuals differing in their gene content. AIM: This study aimed to investigate KIR diversity among the northern Indian population who share features with either Western Eurasian or East Asian populations. It sought to decipher how northern Indians are associated phylogenetically with global populations whilst also focusing on differentiation of populations. SUBJECTS AND METHODS: This paper studied 867 northern Indians using PCR-SSP. Gene and genotypic frequencies were calculated, using statistical analyses. Findings were compared against 76 global populations of differing ethnicities. RESULTS: This northern Indian population shared characteristics with Western Eurasian or Asian Indian populations, as is evident from genetic distance, clustered heatmap, phylogenetic assessment and principal component analysis. The findings are consistent with the demographic history of northern India, including specific features, such as presence of comparatively high KIR B-haplotype as compared to A-haplotype. CONCLUSION: KIR frequencies and profiles of northern Indians were more similar to Western Eurasians, Africans and Asian Indians. This may suggest that KIR genes are under constant evolutionary pressures and selection, which may be linked to different invading pathogens.


Asunto(s)
Pueblo Asiatico/genética , Etnicidad/genética , Receptores KIR/genética , Frecuencia de los Genes , Variación Genética , Genotipo , Haplotipos , Humanos , India , Reacción en Cadena de la Polimerasa
15.
J Gastroenterol Hepatol ; 28(10): 1678-85, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23962084

RESUMEN

BACKGROUND AND AIM: Angiogenesis plays a key role in growth, progression, and metastasis of various cancers. Vascular endothelial growth factor (VEGF) polymorphism has been associated with several cancers. Role of VEGF has not been reported in gallbladder cancer (GBC). Present study was designed to investigate the role of VEGF polymorphism in GBC and in other (benign) gallbladder diseases, that is chronic cholecystitis (CC) and xanthogranulomatous cholecystitis (XGC). METHODS: Blood samples were collected from 195 GBC, 140 CC, and 47 XGC patients and 300 normal healthy controls. VEGF polymorphisms were investigated using amplification refractory mutation system polymerase chain reaction for g.43737830A>G and g.3437A>C, polymerase chain reaction-restriction fragment length polymorphism for c.*237C>T, and g.43736418delTinsG amplified by polymerase chain reaction. RESULTS: At g.43737830A>G, GA genotype showed susceptibility (odds ratio [OR] = 1.65 and OR = 1.68) and GG genotype showed protective association (OR = 0.58 and OR = 0.50) with GBC and CC. Allele A of VEGF g.43737830A>G was risk associated with GBC and CC (OR = 1.48 and OR = 1.70), while G allele was risk protective for GBC and CC (OR = 0.67 and OR = 0.58). At g.3437A>C, genotype CA was risk protective for GBC (OR = 0.61). TT genotype of c.*237C>T was susceptible for GBC and CC (OR = 2.59 and OR = 3.48), while CC genotype was risk protective for GBC and CC (OR = 0.61 and OR = 0.34). T allele of c.*237C>T polymorphism was risk associated with GBC and CC (OR = 1.63 and OR = 2.90), while C allele was risk protective for GBC and CC (OR = 0.38 and OR = 0.28). Haplotype I-C-A-C was risk protective for GBC (OR = 0.27). CONCLUSION: The present study suggests that c.*237C>T and g.43737830A>G polymorphisms are useful markers of susceptibility to GBC.


Asunto(s)
Neoplasias de la Vesícula Biliar/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Factor A de Crecimiento Endotelial Vascular/genética , Colecistitis/genética , Enfermedad Crónica , Femenino , Frecuencia de los Genes , Genotipo , Granuloma/genética , Haplotipos , Humanos , Masculino , Riesgo , Xantomatosis/genética
16.
Indian J Med Res ; 137(1): 203-9, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-23481074

RESUMEN

BACKGROUND & OBJECTIVES: Studies have demonstrated the effect of CYP2C9 (cytochrome P450) and VKORC1 (vitamin K epoxide reductase complex) gene polymorphisms on the dose of acenocoumarol. The data from India about these gene polymorphisms and their effects on acenocoumarol dose are scarce. The aim of this study was to determine the occurrence of CYP2C9*2,*3 and VKORC 1 -1639G>A gene polymorphisms and to study their effects on the dose of acenocoumarol required to maintain a target International Normalized Ratio (INR) in patients with mechanical heart valve replacement. METHODS: Patients from the anticoagulation clinic of a tertiary care hospital in north India were studied. The anticoagulation profile, INR (International Normalized Ratio) values and administered acenocoumarol dose were obtained from the clinical records of patients. Determination of the CYP2C9*2,*3 and VKORC1 -1639G>A genotypes was done by PCR-RFLP (restriction fragment length polymorphism). RESULTS: A total of 111 patients were studied. The genotype frequencies of CYP2C9 *1/*1,*1/*2,*1/*3 were as 0.883, 0.072, 0.036 and that of VKORC1 -1639G>A for GG, AG, and AA genotypes were 0.883, 0.090, and 0.027, respectively. The percentage of patients carrying any of the variant alleles of CYP2C9 and VKORC1 in heterozygous or homozygous form was 34% among those receiving a low dose of ≤20 mg/wk while it was 13.8 per cent in those receiving >20 mg/wk (P=0.014). A tendency of lower dose requirements was seen among carriers of the studied polymorphisms. There was considerable variability in the dose requirements of patients with and without variant alleles. INTERPRETATION & CONCLUSIONS: The study findings point towards the role of CYP2C9 and VKORC1 gene polymorphisms in determining the inter-individual dose variability of acenocoumarol in the Indian patients with mechanical heart valve replacement.


Asunto(s)
Acenocumarol/administración & dosificación , Anticoagulantes/administración & dosificación , Hidrocarburo de Aril Hidroxilasas/genética , Vitamina K Epóxido Reductasas/genética , Adulto , Alelos , Biomarcadores Farmacológicos , Citocromo P-450 CYP2C9 , Femenino , Genotipo , Implantación de Prótesis de Válvulas Cardíacas , Válvulas Cardíacas/efectos de los fármacos , Válvulas Cardíacas/enzimología , Válvulas Cardíacas/cirugía , Humanos , India , Relación Normalizada Internacional , Masculino , Polimorfismo Genético
17.
Rheumatol Int ; 33(9): 2359-63, 2013 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-23543349

RESUMEN

Antibodies to citrullinated peptides(ACPA) have high specificity for diagnosis and prognosis in rheumatoid arthritis (RA). ACPA are of IgG isotype and have an association with shared epitope-bearing HLA DR allele, suggesting that T cell help is needed for their generation. In mice models, T cell reactive to citrullinated self-peptide have been reported however, the human data is limited. Patients with RA satisfying ACR criteria were included and peripheral blood obtained for lymphoproliferative assay, antibody level and HLA typing. Citrullinated (Cit) and native peptides of Vimentin and Aggrecan were used for stimulating peripheral blood mononuclear cells in 5-day cultures. A SI value above >2.0 was taken as significant. HLA typing was done by SSCP and ACPA were tested by ELISA. A total of 50 patients (45 females; mean age 42 years; mean duration of disease 7 years) with RA were included in the study. A total of 90 % were RF positive and 78 % were ACPA positive. A total of 28 patients showed response to Agg peptide with 21 of them showing higher response to CitAgg as compared to native Agg peptide as well as the median SI was higher with CitAgg (6.07 Vs. 5.09; p = 0.009). A total of 31 patients showed response to Vim peptide with response to native peptide being higher than CitVim peptide in 22 of the patients. There was no association of T cell response with presence of shared epitope. Nearly half the patients with RA show T cell response to aggrecan and vimentin peptides; however, citrullination is not crucial for T cell response.


Asunto(s)
Agrecanos/inmunología , Artritis Reumatoide/inmunología , Autoanticuerpos/sangre , Citrulina/inmunología , Linfocitos T/inmunología , Vimentina/inmunología , Adulto , Femenino , Antígeno HLA-DR4/genética , Humanos , Masculino , Persona de Mediana Edad
18.
Arch Gynecol Obstet ; 287(2): 375-81, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-22990475

RESUMEN

PURPOSE: Role of thrombophilic factor (FV) in the etiology of recurrent miscarriages is not confirmed till date. It has been hypothesized that thrombophilic G1691A factor V Leiden (FVL), if detected well ahead in time among recurrent miscarriages may be a treatable. The role of FVL mutation in the pathogenesis of sporadic and recurrent miscarriages among North Indian women was studied to construct the frequency data in this part of the country. Further, we have evaluated the cost-benefit factor. METHODS: This is a case-control study, women with recurrent miscarriages (n = 1,000) as cases and healthy parous women (n = 500) as controls were enrolled in the study between January 2003 and January 2012. DNA was extracted from peripheral blood and analyzed for the presence of FVL mutation and prothrombin gene polymorphism (G20210A). We have carried out the meta-analysis taking into consideration 20 other world populations. RESULTS: In total, 50 (5.0 %) cases and 12 (2.4 %) controls were heterozygous for the FVL mutation. The incidence of FVL was higher in recurrent miscarriage cases as compared to the control group (OR 2.14; 95 % CI 1.12-4.05). CONCLUSION: Our results revealed the absence of FVL mutation in a homozygous state among patients and controls. Although the heterozygous mutation is almost double in cases as compared to controls, we still suggest that looking at the cost-benefit analysis this test may not be included in the battery of tests performed on recurrent miscarriages among North Indians from this part of the country.


Asunto(s)
Aborto Habitual/genética , Factor V/genética , Pruebas Genéticas , Mutación Puntual , Polimorfismo de Nucleótido Simple , Protrombina/genética , Aborto Habitual/economía , Adulto , Estudios de Casos y Controles , Análisis Costo-Beneficio , Análisis Mutacional de ADN , Femenino , Estudios de Asociación Genética , Marcadores Genéticos , Pruebas Genéticas/economía , Técnicas de Genotipaje , Heterocigoto , Humanos , India , Embarazo , Estudios Retrospectivos
19.
Arch Gynecol Obstet ; 288(5): 1171-7, 2013 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-23685927

RESUMEN

PURPOSE: The aim of this study was to investigate the association between MTHFR C677T, A1298C, MTHFD G1958A and plasminogen activator inhibitor type 1 (PAI-1) 4G/5G polymorphism among first trimester recurrent miscarriages. MATERIALS AND METHODS: DNA was extracted from peripheral blood samples from 200 patients and 300 controls. Polymerase chain reaction (PCR), restriction fragment length polymorphism (RFLP) and sequencing were used to identify the polymorphisms. We have analyzed the frequencies, odds ratio, Hardy-Weinberg equilibrium. RESULTS: MTHFR C677T, A1298C, and MTHFD G1958A variant alleles were found to be significantly more prevalent in patients than control. However, variant genotype of MTHFR C677T (OR = 2.54; 95 % CI = 1.23-5.24; p value = 0.014), 1298C (OR = 2.23; 95 % CI = 1.09-4.52; p value = 0.028), and MTHFD-1958 showed significant association with pregnancy loss (OR = 2.36; 95 % CI = 1.39-4.02; p value = 0.002). Both MTHFR 677 and MTHFD 1958 showed susceptible effect under recessive model of inheritance. PAI-1 mutations showed no significance. CONCLUSION: We observed significant susceptible effects of MTHFR C677T, A1298C, and MTHFD G1958A among RM cases. Our data points toward the multifactorial nature of the recurrent miscarriage as relative contribution of variant genotype of MTHFR C677T is only twofold and further decreased to only onefold, and MTHFD-1958 lost its significance upon meta-analysis.


Asunto(s)
Aborto Habitual/genética , Metilenotetrahidrofolato Deshidrogenasa (NADP)/genética , Metilenotetrahidrofolato Reductasa (NADPH2)/genética , Inhibidor 1 de Activador Plasminogénico/genética , Polimorfismo Genético , Estudios de Casos y Controles , Análisis Mutacional de ADN , Femenino , Haplotipos , Humanos , India , Embarazo
20.
Cytokine ; 60(2): 456-62, 2012 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-22727980

RESUMEN

CONTEXT: CTLA-4 is engaged on effector cells that may alter signal transduction and subsequently cytokine production. The transmission of longer repeats of (AT)(n) alleles of CTLA-4 is also associated with women undergoing recurrent miscarriage. The TNF-α known as an embryo-toxic cytokine is reported to be greater in placentas of abortion prone pregnancies. OBJECTIVES: The present study investigated the role of CTLA-4+49 A/G, CTLA-4 (AT)(n) 3'UTR, TNF-α-308G/A and TNF-α-238G/A polymorphisms as a susceptibility marker for recurrent miscarriage (RM). PARTICIPANTS AND METHODS: We genotyped CTLA4+49 A/G, TNF-α-308 and TNF-α-238 gene polymorphisms in 300 patients with RM and 500 age and ethnically matched negative controls using PCR-RFLP method. While gene sequencing method was adopted for studying the CTLA-4 (AT)(n) 3'UTR polymorphism. RESULTS: The mutant homozygous genotype GG of CTLA4+49A/G, AA genotype and A allele of TNF-α-308, G allele of TNF-α-238 were observed to be predisposing among RM cases along with the 104 bp, 106 bp, 110 bp and 116 bp alleles of CTLA-4 (AT)(n) microsatellite repeat. GA and AG haplotypes of TNF-α were low risk associated haplotypes among recurrent miscarriage women. CONCLUSIONS: Roles of CTLA-4 A49G, CTLA-4 (AT)(n) 3'UTR, TNF-α-308 and TNF-α-238 polymorphisms in RM cases from North India is reflected through this study.


Asunto(s)
Aborto Habitual/genética , Antígeno CTLA-4/genética , Estudios de Asociación Genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple/genética , Factor de Necrosis Tumoral alfa/genética , Estudios de Casos y Controles , Intervalos de Confianza , Demografía , Femenino , Frecuencia de los Genes/genética , Haplotipos/genética , Humanos , India , Metaanálisis como Asunto , Oportunidad Relativa
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