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1.
Int J Immunogenet ; 43(3): 125-30, 2016 Jun.
Article in English | MEDLINE | ID: mdl-26991115

ABSTRACT

In this study, we aimed to test the hypothesis that KIR haplotypes (that interact with HLA class I molecules) are associated with susceptibility in patients with T1DM in utero through maternal-foetal interaction of KIR and their HLA class I ligands in Han Chinese population. We determined the KIR genes and KIR/ligand gene combination frequencies in 59 Han Chinese children with T1D and their mothers and compared it with 159 healthy control children and their mothers. The absence of KIR-2DS1 in the mother and the presence of HLA-C2 ligand in the child were negatively associated with type 1 diabetes in the child. Our results indicate that maternal KIR genes and their interaction with foetal HLA-C2 may contribute to the risk of type 1 diabetes among Han Chinese children.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease , HLA-C Antigens/genetics , Receptors, KIR/genetics , Adult , Asian People , Child , Child, Preschool , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 1/pathology , Female , Genetic Association Studies , HLA-C Antigens/immunology , Haplotypes/genetics , Histocompatibility, Maternal-Fetal/genetics , Humans , Ligands , Male , Receptors, KIR/immunology
2.
Diabet Med ; 33(1): 91-6, 2016 Jan.
Article in English | MEDLINE | ID: mdl-26031759

ABSTRACT

AIM: Killer immunoglobulin-like receptors (KIRs) and their interaction with HLA class I ligands have been shown to be associated with Type 1 diabetes mellitus. The aim of our study was to investigate the influence of KIR genes and their HLA-C ligands for susceptibility to Type 1 diabetes in patients from Eastern India. METHODS: A total of 135 patients with Type 1 diabetes and 98 healthy subjects from Eastern India were typed for KIR genes and HLA-C ligands using PCR-based genotyping. The frequencies of these genes were compared between patients and controls. RESULTS: Comparison of KIR genes between Type 1 diabetes patients and healthy subjects revealed significantly different frequencies of KIRs 2DL2 and 2DS4. The presence of HLA-C1 was negatively associated with disease. The presence of both HLA-C1 and -C2 showed a negative association with Type 1 diabetes, whereas the absence of C1 and presence of C2 was positively associated with disease. Stratification analysis of HLA-C ligands and KIRs showed significant associations between Type 1 diabetes and 2DL2+/C1-, 2DL2-/C1+, 2DL3+/C1+, 2DL3+/C1- and 2DS2+/C1-. CONCLUSIONS: Our results suggest that the interaction of KIRs with HLA-C ligands are significant and certain combinations contribute to susceptibility to and protection against Type 1 diabetes.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease , HLA-C Antigens/blood , Natural Killer T-Cells/metabolism , Polymorphism, Genetic , Receptors, KIR2DL2/genetics , Receptors, KIR2DL3/genetics , Receptors, KIR/genetics , Alleles , Diabetes Mellitus, Type 1/blood , Diabetes Mellitus, Type 1/immunology , Diabetes Mellitus, Type 1/metabolism , Disease Susceptibility , Gene Expression Regulation , Gene Frequency , Genetic Association Studies , HLA-C Antigens/genetics , HLA-C Antigens/metabolism , Humans , India , Ligands , Natural Killer T-Cells/immunology , Receptors, KIR/agonists , Receptors, KIR/blood , Receptors, KIR/metabolism , Receptors, KIR2DL2/agonists , Receptors, KIR2DL2/blood , Receptors, KIR2DL2/metabolism , Receptors, KIR2DL3/agonists , Receptors, KIR2DL3/blood , Receptors, KIR2DL3/metabolism
3.
Genes Immun ; 16(8): 541-51, 2015 Dec.
Article in English | MEDLINE | ID: mdl-26513234

ABSTRACT

The possible interrelations between human leukocyte antigen (HLA)-DQ, non-HLA single-nucleotide polymorphisms (SNPs) and islet autoantibodies were investigated at clinical onset in 1-34-year-old type 1 diabetes (T1D) patients (n=305) and controls (n=203). Among the non-HLA SNPs reported by the Type 1 Diabetes Genetics Consortium, 24% were supported in this Swedish replication set including that the increased risk of minor PTPN22 allele and high-risk HLA was modified by GAD65 autoantibodies. The association between T1D and the minor AA+AC genotype in ERBB3 gene was stronger among IA-2 autoantibody-positive patients (comparison P=0.047). The association between T1D and the common insulin (AA) genotype was stronger among insulin autoantibody (IAA)-positive patients (comparison P=0.008). In contrast, the association between T1D and unidentified 26471 gene was stronger among IAA-negative (comparison P=0.049) and IA-2 autoantibody-negative (comparison P=0.052) patients. Finally, the association between IL2RA and T1D was stronger among IAA-positive than among IAA-negative patients (comparison P=0.028). These results suggest that the increased risk of T1D by non-HLA genes is often modified by both islet autoantibodies and HLA-DQ. The interactions between non-HLA genes, islet autoantibodies and HLA-DQ should be taken into account in T1D prediction studies as well as in prevention trials aimed at inducing immunological tolerance to islet autoantigens.


Subject(s)
Autoantibodies/immunology , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , HLA-DQ Antigens/genetics , Islets of Langerhans/immunology , Adolescent , Adult , Autoantibodies/genetics , Child , Child, Preschool , HLA-DQ Antigens/immunology , Humans , Infant , Polymorphism, Single Nucleotide , Protein Tyrosine Phosphatase, Non-Receptor Type 22/genetics , Receptor, ErbB-3/genetics , Young Adult
4.
Roum Arch Microbiol Immunol ; 73(1-2): 43-50, 2014.
Article in English | MEDLINE | ID: mdl-25518570

ABSTRACT

BACKGROUND: The population is not always homogeneous in relation to the representation and functioning of genes. Therefore, the presence of allogenicity is a universal phenomenon. The profound variability is noticed among the members of the human population with reference to the resistance against infections and late onset of diseases. In this line, a few sets of alleles which come under the domain of immune function namely KIRs (Killer immunoglobulin-like receptor genes) and HLA-I have been chosen to report in the population of Puttaparthi (India). OBJECTIVES: The genotyping of the population is the current ongoing focus of our team wherein the distribution of the following alleles has been taken up in the mixed ethnic groups of Puttaparthi as a prelude to earmark them as genotypic markers in future studies relating to susceptible diseases. METHODS: The PCR protocols for the identified immune related genes viz., KIR- 2DL1, 2DL2, 2DL3, 2DL4, 2DL5, 3DL1, 3DL2, 3DL3, 3DS1, 2DS1, 2DS2, 2DS3, 2DS4, 2DS5, 2DP1, 3DP1; HLA- C1 and HLA-C2 have been standardized. RESULTS & INTERPRETATION: In the present study, except KIR 2DL2, the other non-framework inhibitory KIR genes were represented at higher percentage and ranged from 57% to 80% in the chosen population which would suggest its higher survival adaptation. Interestingly, the majority of activating KIR genes were least represented and varied between 5% to 32.5% which is also in compliance with the survival adaptation of the chosen population. The carrier gene frequencies of KIRs were compared with the other populations' viz., Chinese Mongolian, Chinese Han, Greek and Brazilian data. The expected heterozygosity of KIR alleles and their rank in gene diversity among the population of Puttaparthi were also discussed.


Subject(s)
Receptors, KIR/genetics , Gene Frequency , Genotype , HLA-C Antigens/genetics , Humans , India , Polymerase Chain Reaction
5.
Heart Asia ; 3(1): 2-7, 2011.
Article in English | MEDLINE | ID: mdl-27325971

ABSTRACT

OBJECTIVES: To determine which anthropometric measurement correlates best with the metabolic abnormalities associated with the metabolic syndrome in adolescents and young adults. DESIGN: Cross-sectional study. SETTING: Schools, high schools and universities. PARTICIPANTS: 1359 adolescents and young adults aged 14-25 years. MAIN OUTCOME MEASURES: Anthropometric predictors of metabolic abnormalities as classified by International Diabetes Federation definition. RESULTS: The waist circumference (OR 1.56, 95% CI 1.0 to 2.43: p≤0.01) and the abdominal skin fold thickness (OR 1.44, 95% CI 1.02 to 2.04, p≤0.01) above the third quintile cut-offs were found to be significantly associated with metabolic abnormalities. The sensitivity of either one of these measurements in predicting metabolic abnormalities was 66.1% with a negative predictive value of 82.8%. Hyperglycaemia was significantly associated with an abdominal skin fold thickness over the fourth quintile alone (OR 1.63, 95% CI 1.24 to 2.1). All the anthropometric measurements correlated well with elevated triglycerides and hypertension. CONCLUSIONS: In a large community-based cross-sectional survey of subjects aged 14-25 years, the waist circumference and the abdominal skin fold thickness are important predictors of the metabolic abnormalities associated with metabolic syndrome. This simple clinical tool may help in a primary care setting to identify subjects who require a further biochemical evaluation and would considerably reduce the cost of unwarranted testing.

6.
Genes Immun ; 11(5): 406-15, 2010 Jul.
Article in English | MEDLINE | ID: mdl-20445565

ABSTRACT

The single nucleotide polymorphism 1858C>T in the PTPN22 gene is associated with type 1 diabetes (T1D) in several populations. Earlier reports have suggested that the association may be modified by human leukocyte antigen (HLA), as well as by islet autoantibodies. In a large case-control study of Swedish incident T1D patients and controls, 0-34 years of age, we tested whether the odds ratio (OR) measure of association was dependent on HLA or autoantibodies against the islet autoantigens glutamic acid decarboxylase 65 kDa autoantibodies (GADA), insulin, islet antigen-2, or islet cell. The association between the carrier status of 1858C>T allele in PTPN22 (PTPN22(CT+TT)) and T1D was modified by HLA. In addition, in GADA-positive T1D, the OR was 2.83 (2.00, 3.99), whereas in GADA-negative T1D, the OR was 1.41 (0.98, 2.04) (P for comparison=0.007). The OR of association between PTPN22(CT+TT) and GADA-positive T1D declined with increasing HLA-risk category from 6.12 to 1.54 (P=0.003); no such change was detected in GADA-negative T1D (P=0.722) (P for comparison=0.001). However, the absolute difference in risk between PTPN22(CC) and PTPN22(CT+TT) subjects with high-risk HLA was five times higher than that for subjects with low-risk HLA. We hypothesize that the altered T-cell function because of the PTPN22(1858C>T) polymorphism is exclusively associated with GADA-positive T1D at diagnosis.


Subject(s)
Autoantibodies/metabolism , Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease/genetics , Glutamate Decarboxylase/immunology , HLA Antigens/genetics , Polymorphism, Single Nucleotide/genetics , Protein Tyrosine Phosphatase, Non-Receptor Type 22/genetics , Adolescent , Adult , Age Factors , Autoantibodies/immunology , Case-Control Studies , Child , Child, Preschool , Female , Genome-Wide Association Study , Genotype , Humans , Infant , Infant, Newborn , Male , Odds Ratio , Risk Assessment , Sweden
7.
Int J Diabetes Dev Ctries ; 29(2): 49-51, 2009 Apr.
Article in English | MEDLINE | ID: mdl-20142867
8.
Int J Immunogenet ; 35(6): 439-46, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19046302

ABSTRACT

Killer immunoglobulin-like receptors (KIRs) are known to modulate natural killer (NK) and NK T-cell function by interacting with human leucocyte antigen (HLA) class I ligands on target cells. The aim of our study was to investigate the influence of KIR2D genes with their HLA-C ligands in susceptibility to type 1 diabetes. A total of 98 type 1 diabetes patients and 70 healthy subjects from Latvia were typed for KIR genes and HLA-C ligands using polymerase chain reaction-based genotyping. The HLA C1+/C2+ combination was positively, and C1-/C2+ combination was negatively, associated with type 1 diabetes. Stratification analysis of KIR/HLA-C ligand combinations showed 2DL2+/C1+, 2DL3+/C1+, and 2DS2+ /C1+ to be positively, and 2DL2-/C1- and 2DS2-/ C1- to be negatively, associated. The presence of 2DL2-HLA-C1 in the absence of 2DS1, 2DS2 confers maximum susceptibility. Absence of 2DL2 and HLA-C1 along with absence of 2DS1 and 2DS2 confer maximum protection. A hypothetical model of KIR/ligand combinations on immune responses and type 1 diabetes susceptibility is proposed. Our results suggest that a combination KIR2DL2- HLA-C1 plays a critical role in susceptibility or protection in Latvians against type 1 diabetes.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease , HLA-C Antigens/genetics , Receptors, KIR2DL2/genetics , Adolescent , Child , Child, Preschool , Female , Gene Frequency , Genotype , Humans , Infant , Infant, Newborn , Latvia , Male , White People/genetics
9.
Indian J Med Res ; 128(4): 448-61, 2008 Oct.
Article in English | MEDLINE | ID: mdl-19106440

ABSTRACT

Cu being a transition metal is ubiquitously engaged in biological systems to derive electrons through its participation in several enzymatic reactions. Upon bestowing the significance of Cu in biological systems, an elaborate mechanism is set forth by nature for maintaining Cu homeostasis. As a consequence, a wide variety of proteins viz., family of Cu bearing proteins, cuproenzymes, Cu transporters and Cu chaperone proteins have been manifested for enabling Cu to show its relevance in biological health. In addition, understanding the role of Cu in hepatic and neuronal functions and also in angiogenesis keeps progressing with the advent of novel molecular tools. The studies on genetic defects in Cu metabolism causing abnormalities are providing insights leading to the possible prognostic cues to alleviate the sufferings.


Subject(s)
Copper/physiology , Biological Transport , Copper/metabolism , Homeostasis , Humans
10.
J Assoc Physicians India ; 56: 875-80, 2008 Nov.
Article in English | MEDLINE | ID: mdl-19263687

ABSTRACT

Epigenetics deals with molecular heritable patterns relating to chromatin, which exists in two alterable and inter-convertible states. The two conformations of chromatin i.e., compact and relaxed are due to epigenetic regulation. The alterations in chromatin normalize gene expression patterns. Thus, the epigenetic marks on chromatin are the deciding factors for either gene silencing or activation. The epigenetics introduced a new term viz., epiallele which deviates from the classical Mendelian allele. The remodeling of chromatin during embryonic phase, post-translational aberrations of chromatin proteins causing cellular dysfunction and possible epigenetic therapies are discussed in the present article. The role of epigenetic mechanisms in triggering / progression of several autoimmune diseases is being emphasized off late. The study of such complex epigenetic processes becomes very important in understanding the etiopathology of the disease as well as in designing target therapies.


Subject(s)
Autoimmune Diseases/genetics , Chromatin/genetics , Epigenesis, Genetic , Genetic Predisposition to Disease , Gene Expression Profiling , Humans
11.
Ann N Y Acad Sci ; 1150: 133-8, 2008 Dec.
Article in English | MEDLINE | ID: mdl-19120281

ABSTRACT

KIRs (killer Ig-like receptors) expressed on natural killer (NK) cells are an important component of innate (and adaptive) immunity. They are either activatory or inhibitory, and certain KIRs are known to interact with specific motifs of HLA Class I molecules, which is very crucial in determining whether a cell is targeted to lysis or otherwise. Latent autoimmune diabetes in adults (LADA) is a slowly progressive form of autoimmune diabetes, with an adult onset (>30 years). Because autoantibodies and autoimmunity involved are involved in the etiology of LADA, KIRs might play an important role in conferring susceptibility to or protection against the disease. The purpose of this study was to identify killer immunoglobulin-like receptor (KIR) genes, which are associated with susceptibility to and protection against type 1 diabetes in Latvian and Asian Indian patients with LADA. KIR and HLA-C ligand genotyping was performed using PCR-SSP in LADA patients from Latvia (n= 45) with age- and sex-matched controls (n= 92) and from India (n= 86) with controls (n= 98). Results showed that in Latvian patients with LADA, KIRs 2DL1, 2DS2, and 2DS4 were associated with susceptibility and KIR 2DS5 with protection. In Asian Indian LADA patients, KIRs 2DL5 and 3DL1 were associated with susceptibility and KIRs 2DS1 and 2DS3 with protection. Stratification analyses for KIRs that bind to HLA-C1 and C2 were performed. We concluded that KIRs are important in conferring susceptibility (or protection) to adult patients with LADA in both our study populations. However the KIR genes (and their HLA-C ligands) conferring susceptibility or protection in these two populations differ, showing a role of ethnicity in disease susceptibility.


Subject(s)
Cytoprotection/genetics , Diabetes Mellitus, Type 1/genetics , Genetic Predisposition to Disease , Receptors, KIR/physiology , Adult , Case-Control Studies , Female , Gene Frequency , Genotype , HLA-C Antigens/genetics , Humans , India , Latvia , Male , Middle Aged , Polymorphism, Genetic/physiology , Population Groups/genetics , Receptors, KIR/genetics
12.
Genes Immun ; 8(6): 503-12, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17641683

ABSTRACT

In a large case-control study of Swedish incident type I diabetes patients and controls, 0-34 years of age, we tested the hypothesis that the GIMAP5 gene, a key genetic factor for lymphopenia in spontaneous BioBreeding rat diabetes, is associated with type I diabetes; with islet autoantibodies in incident type I diabetes patients or with age at clinical onset in incident type I diabetes patients. Initial scans of allelic association were followed by more detailed logistic regression modeling that adjusted for known type I diabetes risk factors and potential confounding variables. The single nucleotide polymorphism (SNP) rs6598, located in a polyadenylation signal of GIMAP5, was associated with the presence of significant levels of IA-2 autoantibodies in the type I diabetes patients. Patients with the minor allele A of rs6598 had an increased prevalence of IA-2 autoantibody levels compared to patients without the minor allele (OR=2.2; Bonferroni-corrected P=0.003), after adjusting for age at clinical onset (P=8.0 x 10(-13)) and the numbers of HLA-DQ A1*0501-B1*0201 haplotypes (P=2.4 x 10(-5)) and DQ A1*0301-B1*0302 haplotypes (P=0.002). GIMAP5 polymorphism was not associated with type I diabetes or with GAD65 or insulin autoantibodies, ICA, or age at clinical onset in patients. These data suggest that the GIMAP5 gene is associated with islet autoimmunity in type I diabetes and add to recent findings implicating the same SNP in another autoimmune disease.


Subject(s)
Autoantibodies/immunology , Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , GTP-Binding Proteins/genetics , Adolescent , Adult , Autoantibodies/blood , Case-Control Studies , Child , Child, Preschool , Diabetes Mellitus, Type 1/metabolism , Female , GTP-Binding Proteins/metabolism , Humans , Infant , Infant, Newborn , Male , Polymorphism, Single Nucleotide , Sweden
13.
Tissue Antigens ; 70(2): 110-27, 2007 Aug.
Article in English | MEDLINE | ID: mdl-17610416

ABSTRACT

The direct involvement of the human leukocyte antigen class II DR-DQ genes in type 1 diabetes (T1D) is well established, and these genes display a complex hierarchy of risk effects at the genotype and haplotype levels. We investigated, using data from 38 studies, whether the DR-DQ haplotypes and genotypes show the same relative predispositional effects across populations and ethnic groups. Significant differences in risk within a population were considered, as well as comparisons across populations using the patient/control (P/C) ratio. Within a population, the ratio of the P/C ratios for two different genotypes or haplotypes is a function only of the absolute penetrance values, allowing ranking of risk effects. Categories of consistent predisposing, intermediate ('neutral'), and protective haplotypes were identified and found to correlate with disease prevalence and the marked ethnic differences in DRB1-DQB1 frequencies. Specific effects were identified, for example for predisposing haplotypes, there was a statistically significant and consistent hierarchy for DR4 DQB1*0302s: DRB1*0405 =*0401 =*0402 > *0404 > *0403, with DRB1*0301 DQB1*0200 (DR3) being significantly less predisposing than DRB1*0402 and more than DRB1*0404. The predisposing DRB1*0401 DQB1*0302 haplotype was relatively increased compared with the protective haplotype DRB1*0401 DQB1*0301 in heterozygotes with DR3 compared with heterozygotes with DRB1*0101 DQB1*0501 (DR1). Our results show that meta-analyses and use of the P/C ratio and rankings thereof can be valuable in determining T1D risk factors at the haplotype and amino acid residue levels.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Diabetes Mellitus, Type 1/immunology , Genetic Predisposition to Disease , HLA-DQ Antigens/genetics , HLA-DR Antigens/genetics , Haplotypes , Europe , Genotype , HLA-DQ beta-Chains , HLA-DRB1 Chains , Humans
14.
Genes Immun ; 8(6): 518-21, 2007 Sep.
Article in English | MEDLINE | ID: mdl-17554341

ABSTRACT

SUMO4 M55V, located in IDDM5, has been a focus for debate because of its association to type I diabetes (TIDM) in Asians but not in Caucasians. The current study aims to test the significance of M55V association to TIDM in a large cohort of Swedish Caucasians, and to test whether M55V is associated in those carrying human leukocyte antigen (HLA) class II molecules. A total of 673 TIDM patients and 535 age- and sex-matched healthy controls were included in the study. PCR-RFLP was performed to identify the genotype and allele variations. Our data suggest that SUMO4 M55V is not associated with susceptibility to TIDM by itself. When we stratified our patients and controls based on heterozygosity for HLA-DR3/DR4 and SUMO4 genotypes, we found that presence of SUMO4 GG increased further the relative risk conferred by HLA-DR3/DR4 to TIDM, whereas SUMO4 AA decreased the risk. From the current study, we conclude that SUMO4 M55V is associated with TIDM in association with high-risk HLA-DR3 and DR4, but not by itself.


Subject(s)
Diabetes Mellitus, Type 1/genetics , HLA-DR3 Antigen/genetics , HLA-DR4 Antigen/genetics , Small Ubiquitin-Related Modifier Proteins/genetics , Adolescent , Adult , Alleles , Case-Control Studies , Child , Child, Preschool , Cohort Studies , Diabetes Mellitus, Type 1/immunology , Female , Genetic Predisposition to Disease , Genotype , HLA-DR3 Antigen/immunology , HLA-DR4 Antigen/immunology , Haplotypes , Humans , Infant , Infant, Newborn , Male , Polymorphism, Single Nucleotide , Small Ubiquitin-Related Modifier Proteins/immunology , Sweden
15.
Int J Immunogenet ; 34(2): 137-42, 2007 Apr.
Article in English | MEDLINE | ID: mdl-17373940

ABSTRACT

Autoimmune diabetes [type 1 diabetes mellitus (T1DM), latent autoimmune diabetes in adults (LADA) and part of malnutrition-related diabetes] has been shown to have genetic predisposition. Studies in IDDM 5 have lead to the discovery of a novel polymorphism 163 A-->G, of SUMO4 (small ubiquitin-related modifier) gene, associated with risk to T1DM in Asians, but not in Caucasians. We studied patients with T1DM (n = 134), patients with LADA (n = 101), patients with malnutrition-modulated diabetes mellitus (n = 66) and patients with fibrocalculous pancreatic diabetes (n = 43) and healthy controls subjects (n = 114) from Cuttack, India. Polymerase chain reaction-sequence-specific primer (PCR-SSP) was used to amplify the 163 A-->G sequences. Restriction fragment length polymorphism (RFLP) was performed using restriction enzyme Taq I (PCR-RFLP). Differences in the allelic frequencies of the A and the G alleles were tested statistically using Fisher's exact test or chi-squared test wherever appropriate. P-values were considered significant when equal to or less than 0.05. No significant association was detected between SUMO4 M55V and T1DM susceptibility in Asian-Indians. Comparison of the A and G alleles with HLA DR3-DR4 did not result in any significant P-values. No significant association was found between SUMO4 M55V and LADA or malnutrition-related diabetes mellitus (MRDM). Our results show that Asian-Indians with T1DM are different from other Asian populations. Asian-Indians show more similarity to Caucasians with respect to the association of SUMO4 M55V variant in T1DM. Association studies on Asian-Indian patients with LADA and MRDM showed no significant difference in the presence of the A and the G alleles when compared to healthy controls.


Subject(s)
Autoimmune Diseases/genetics , Diabetes Mellitus, Type 1/genetics , Small Ubiquitin-Related Modifier Proteins/genetics , Asian People/genetics , Case-Control Studies , Female , Gene Frequency , Genetic Predisposition to Disease , Humans , India/ethnology , Male , Polymerase Chain Reaction , Polymorphism, Genetic , Polymorphism, Restriction Fragment Length
16.
Tissue Antigens ; 65(3): 252-9, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15730517

ABSTRACT

Natural killer (NK) cells are involved both in control of virus infections and in elimination of tumor cells. Killer immunoglobulin-like receptors (KIRs) either activate or inhibit NK cell-mediated cytolysis, protecting healthy cells from destruction while enabling killing of abnormal cells. To investigate whether KIR genes or genotypes are associated with cervical carcinogenesis, a nested case-control study of 65 case women with cervical intraepithelial neoplasia (CIN) diagnosed during a 6-year follow-up of 15,234 women and 150 control women from the same cohort that remained healthy was performed. More than 70 different genotypes were observed, and 33 of which had not been described previously. An A-genotype including KIR2DL1, KIR2DL2, KIR2DL3, KIR2DL4, KIR3DL1, KIR3DL2, KIR3DL3, and KIR2DS4 was associated with increased risk of CIN (OR 6.7; 95% CI 1.7-26.3), and KIR2DL5B*002 appeared to have an inverse association with disease (OR 0.5; 95% CI 0.5-2.9). There was no association of CIN with the number of activating KIR genes. There was also no association between KIR genes and type of human papilloma virus or with other CIN-related immune response genes. It was concluded that certain KIR genes and genotypes may associate with cervical neoplasia.


Subject(s)
Receptors, Immunologic/genetics , Uterine Cervical Dysplasia/genetics , Uterine Cervical Neoplasms/genetics , Adult , Aged , Alleles , Case-Control Studies , Cohort Studies , Female , Gene Frequency , Genetic Markers , Genetic Testing , Genotype , Humans , Middle Aged , Papillomaviridae/genetics , Population/genetics , Receptors, KIR , Receptors, KIR2DL1 , Receptors, KIR2DL2 , Receptors, KIR2DL3 , Receptors, KIR2DL4 , Receptors, KIR2DL5 , Receptors, KIR3DL1 , Receptors, KIR3DL2 , Uterine Cervical Neoplasms/diagnosis , Uterine Cervical Neoplasms/virology , Uterine Cervical Dysplasia/diagnosis , Uterine Cervical Dysplasia/virology
17.
Rheumatology (Oxford) ; 44(3): 287-92, 2005 Mar.
Article in English | MEDLINE | ID: mdl-15522921

ABSTRACT

OBJECTIVE: To evaluate the contribution of the MHC class I chain-related A (MICA) gene polymorphism to the genetic risk of systemic lupus erythematosus (SLE). METHODS: HLA-DRB1-DQA1-DQB1 genotyping, MICA exon 5 microsatellite genotyping and HLA-B8 genotyping were performed in 48 Italian SLE patients and in 158 healthy control subjects. RESULTS: Of HLA class II haplotypes, only DRB1*03-DQA1*0501-DQB1*0201 (DR3-DQ2) was significantly more frequent among SLE patients than among healthy control subjects [odds ratio (OR) = 6.5, corrected P < 0.0026]. HLA-B8 was detected in 31% SLE patients and 13% healthy control subjects (OR = 3.0, P = 0.005). The allele-wise comparison between patients and controls showed that both MICA5 (OR = 2.5, corrected P < 0.0005) and MICA5.1 (OR = 2.4, corrected P < 0.0005) were positively and MICA9 (OR = 0.2, corrected P < 0.0005) was negatively associated with the disease. The MICA5/5.1 genotype was positively associated with SLE (OR = 28.9, corrected P < 0.0015) also in subjects negative for DR3-DQ2 (OR > 22.6, corrected P < 0.011). The simultaneous presence of DR3-DQ2 and MICA5.1 was detected in 15/48 (31%) SLE and in 10/158 (6%) healthy control subjects (OR = 6.7, corrected P < 0.011). The simultaneous combination of DR3-DQ2 and MICA5 was found in 10/48 (21%) SLE patients and in only 1/158 healthy control subjects (OR = 41.3, corrected P < 0.011). Logistic regression analysis showed the independent positive associations of MICA5 and MICA5.1 and negative association of MICA9 with the disease, and revealed that the interaction of the three major markers (DR3-DQ2, MICA5 and MICA5.1) was associated with increasing genetic risk, which was highest (OR > 30.3) in DR3-DQ2-positive subjects carrying the MICA5-5.1 genotype. CONCLUSIONS: Our study provides the first demonstration of the independent association of the MICA gene polymorphism with genetic risk of SLE.


Subject(s)
Histocompatibility Antigens Class I/genetics , Lupus Erythematosus, Systemic/genetics , Polymorphism, Genetic/genetics , Adult , Aged , Alleles , Female , Genetic Markers/genetics , Genetic Predisposition to Disease/genetics , Genotype , HLA-B8 Antigen/genetics , HLA-DQ Antigens/genetics , HLA-DR3 Antigen/genetics , Haplotypes , Histocompatibility Antigens Class II/genetics , Humans , Linkage Disequilibrium/genetics , Male , Membrane Proteins/genetics , Middle Aged
18.
Eur J Immunogenet ; 31(2): 73-6, 2004 Apr.
Article in English | MEDLINE | ID: mdl-15086346

ABSTRACT

The attraction of leukocytes to tissues is essential for inflammation and the initiation of the autoimmune reaction. The process is controlled by chemokines, which are chemotactic cytokines. We investigated whether human chemokine receptor gene polymorphisms, namely CCR5-Delta32 and CCR2-64I, are associated with susceptibility to autoimmune Addison's disease. Genotyping was performed in 56 patients and 127 healthy controls by a new method using pyrosequencing for CCR2-64I and by polymerase chain reaction and detecting gel for CCR5-Delta32. None of the CCR2 or CCR5 alleles was found to be associated, either positively or negatively, with disease risk. Our results indicate that the CCR2-64I and CCR5-Delta32 gene polymorphisms do not play a major role in conferring genetic risk for, and/or protection against, autoimmune Addison's disease.


Subject(s)
Addison Disease/genetics , Polymorphism, Genetic , Receptors, CCR5/chemistry , Receptors, Chemokine/genetics , Adult , Aged , Alleles , Child , Female , Gene Frequency , Haplotypes , Humans , Male , Middle Aged , Odds Ratio , Receptors, CCR2
19.
Ann N Y Acad Sci ; 1037: 118-21, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15699503

ABSTRACT

While type 2 diabetic subjects in developed countries are predominantly obese or overweight, those in India are often nonobese or lean. The reasons for leanness in these subjects has not been well understood. We assessed the prevalence of pancreatic islet autoimmunity in 83 lean adult subjects (BMI < 18.5 kg/m(2)) with type 2 diabetes by measuring antibodies to glutamic acid decarboxylase-65 (GAD Abs). Positivity to GAD Ab was present in 21 (25.3%) subjects. In addition, subjects with GAD Ab positivity were younger and had lower beta cell function (homeostasis model assessment, HOMA) as compared to the GAD Ab-negative group. This suggests that the antibody-positive group could have a slowly progressive form of type 1 diabetes.


Subject(s)
Antibodies/analysis , Diabetes Mellitus, Type 2/epidemiology , Diabetes Mellitus, Type 2/immunology , Glutamate Decarboxylase/immunology , Thinness , Adult , Age of Onset , Aged , Biomarkers/analysis , Body Mass Index , Diabetes Mellitus, Type 2/diagnosis , Humans , India/epidemiology , Islets of Langerhans/immunology , Middle Aged , Prevalence , Radioimmunoassay
20.
Ann N Y Acad Sci ; 1037: 138-44, 2004 Dec.
Article in English | MEDLINE | ID: mdl-15699508

ABSTRACT

Type 1 diabetes mellitus (T1DM) is an autoimmune disease known to occur in genetically susceptible individuals after exposure to certain unknown environmental factors. HLA-DR3-DQ2 or DR4-DQ8 are established genetic markers for the disease. MHC class I chain-related gene-A (MICA) gene polymorphism has been proposed to be associated with T1DM. To identify the environmental factors and for implementing intervention trials to prevent T1DM, it is important to screen subjects at genetically increased risk for developing T1DM. The All Babies in Southeast Sweden (ABIS) study aims to assess the risk of future progression to T1DM in the general child population. In the present report, we studied the frequency of MICA alleles among newborn babies carrying high-risk HLA DQ2 or DQ8. Of 2821 newborns, we found 563 subjects positive for DQ2, 583 subjects positive for DQ8, 133 subjects positive for DQ2-DQ8 (heterozygous), and 1013 subjects positive for either DQ2 or DQ8. Of these 1013 babies, we typed 499 babies for MICA. Frequency of MICA5 was 38% among DQ8+, 35% among for DQ2-DQ8 (heterozygous) positives, and 22.5% among DQ2+ babies. Frequency of MICA5.1 was 81% among DQ+, 62% among DQ8+, and 71% among DQ2-DQ8 (heterozygous) positives. Frequency of MICA6 was between 20% and 22% among the three groups. Frequency of MICA5/5.1 was 19% among DQ2-DQ8 (heterozygous) positives and between 12% and 13% among those positive for DQ2, DQ8, DQ2, or DQ8. The results from genetic typing in this study would be useful, in conjunction with results from autoantibody analysis that are prospectively being followed-up in all the babies, to develop an approach for identifying children at risk for developing T1DM. Inclusion of MICA typing in addition to HLA could be useful for screening of genetic markers associated with T1DM.


Subject(s)
Diabetes Mellitus, Type 1/genetics , Gene Frequency , Genetic Predisposition to Disease , HLA-DQ Antigens/genetics , Histocompatibility Antigens Class I/genetics , Alleles , Diabetes Mellitus, Type 1/immunology , Haplotypes , Heterozygote , Humans , Incidence , Infant, Newborn , Neonatal Screening , Sweden
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