Prevalence of ICA-12 and other autoantibodies in north Indian patients with early-onset diabetes

Shared and distinct genetics of pure type 1 diabetes and type 1 diabetes with celiac disease, homology in their auto-antigens and immune dysregulation states: a study from North India

AIM

This study was undertaken to explicate the shared and distinctive genetic susceptibility and immune dysfunction in patients with T1D alone and T1D with CD (T1D + CD).

METHODS

A total of 100 T1D, 50 T1D + CD and 150 healthy controls were recruited. HLA-DRB1/DQB1 alleles were determined by PCR-sequence-specific primer method, SNP genotyping for CTLA-4 and PTPN22 was done by simple probe-based SNP-array and genotyping for INS-23 Hph1 A/T was done by RFLP. Autoantibodies and cytokine estimation was done by ELISA. Immune-regulation was analysed by flow-cytometry. Clustering of autoantigen epitopes was done by epitope cluster analytical tool.

RESULTS

Both T1D alone and T1D + CD had a shared association of DRB1*03:01, DRB1*04, DRB3*01:07/15 and DQB1*02. DRB3*01:07/15 confers the highest risk for T1D with relative risk of 11.32 (5.74-22.31). Non-HLA gene polymorphisms PTPN22 and INS could discriminate between T1D and T1D + CD. T1D + CD have significantly higher titers of autoantibodies, expression of costimulatory molecules on CD4 and CD8 cells, and cytokine IL-17A and TGF-β1 levels compared to T1D patients. Epitopes from immunodominant regions of autoantigens of T1D and CD clustered together with 40% homology.

CONCLUSION

Same HLA genes provide susceptibility for both T1D and CD. Non-HLA genes CTLA4, PTPN22 and INS provide further susceptibility while different polymorphisms in PTPN22 and INS can discriminate between T1D and T1D + CD. Epitope homology between autoantigens of two diseases further encourages the two diseases to occur together. The T1D + CD being more common in females along with co-existence of thyroid autoimmunity, and have more immune dysregulated state than T1D alone.

Prevalence of Organ-Specific Autoimmunity in Patients With Type 1 Diabetes Mellitus

INTRODUCTION

Type 1 diabetes mellitus (T1DM) is associated with other autoimmune disorders that are characterized by presence of organ-specific autoantibodies. The present study was undertaken to assess the prevalence of organ-specific autoantibodies among newly diagnosed T1DM subjects of India and to study its relationship with glutamic acid decarboxylase antibody (GADA). We also compared the clinical and biochemical parameters in GADA-positive and -negative T1DM subjects.

METHODS

In a hospital-based cross-sectional study, we studied 61 patients with newly diagnosed T1DM ≤ 30 years of age. T1DM was diagnosed on the basis of acute onset of osmotic symptoms with or without ketoacidosis, severe hyperglycaemia [blood glucose > 13.9 mmol/l (>250 mg/dl)] and insulin requirement from the onset of diabetes. Subjects were screened for autoimmune thyroid disease (thyroid peroxidase antibody [TPOAb]), celiac disease (tissue transglutaminase antibody [tTGAb]), and gastric autoimmunity (parietal cell antibody [PCA]).

RESULTS

Of the 61 subjects, more than one-third (38%) had at least one positive organ-specific autoantibody. In particular, 13 (21.3%) were found to be positive for TPOAb, nine (14.8%) were positive for tTGAb and 11 (18%) were positive for PCA. GADA was positive in 15 (25%) subjects. The frequency of TPOAb tended to be higher in patients who had GADA positivity compared with those with no circulating GADA (40% vs. 15.2%; p=0.07). Subjects positive for GADA were also more likely to be PCA positive compared with those who were GADA negative (40 vs.10.9%, p=0.02). There were no differences in frequency of diabetic ketoacidosis, body mass index, hemoglobin A1C (HbA1c), insulin requirement or fasting C-peptide in GADA-positive and -negative patients.

CONCLUSION

We support the recommendation for regular screening of organ-specific autoantibodies, in particular TPOAb, tTGAb and PCA in all patients with T1DM. Detection of these autoantibodies at onset may prevent complications associated with delayed diagnosis of these disorders. We also conclude that there is higher frequency of TPOAb and PCA in GADA-positive T1DM patients as compared to negative ones. However, patients with positive GADA had similar clinical and biochemical parameters compared to GADA-negative subjects. Lastly, low GADA positivity in our study cohort as compared to Western populations suggests the heterogenous nature of T1DM in the Indian population.

High prevalence of idiopathic (islet antibody-negative) type 1 diabetes among Indian children and adolescents

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.

Differential HLA Association of GAD65 and IA2 Autoantibodies in North Indian Type 1 Diabetes Patients

The human leucocyte antigen (HLA) association with type 1 diabetes (T1D) is well known but there are limited studies investigating the association between β-cell autoantibodies and HLA genes. We evaluated the prevalence of GAD65 and IA-2 autoantibodies (GADA and IA2A) in 252 T1D patients from North India and investigated the genetic association of GADA and IA2A with HLA class I and class II genes/haplotypes. GADA and IA2A were detected in 50.79% and 15.87% of T1D patients, respectively, while only 8.73% had both GADA and IA2A. HLA-DRB1^∗03 was observed to be significantly higher in GADA+ T1D patients as compared to GADA- (91.41% vs. 66.13%, Bonferroni-corrected P (P _c) = 1.11 × 10^-5; OR = 5.45; 95% CI: 2.67-11.08). Similarly, HLA-DQB1^∗02 was found to be significantly increased in GADA+ patients (94.53%, P _c = 2.19 × 10^-5; OR = 6.27; 95% CI: 2.7-14.49) as compared to GADA- (73.39%). The frequencies of HLA-DRB1^∗04 and DQB1^∗03 were increased in IA2A+ patients (45.0% and 52.5%, respectively) as compared to that in IA2A- (25.94% and 33.96%, respectively). Further, the frequency of DRB1^∗03-DQB1^∗02 haplotype was found to be significantly increased in GADA+ T1D patients as compared to GADA- (60.55% vs. 41.94%, P = 3.94 × 10^-5; OR = 2.13; 95%CI = 1.49-3.03). Similarly, HLA-DRB1^∗04-DQB1^∗03 haplotype was found to be significantly increased in IA2A+ T1D patients compared to IA2A- patients (22.5% vs. 12.97%; P = 0.041; OR = 1.95; 95%CI = 1.08-3.52). None of the HLA class I genes (HLA-A, B, and Cw) was found to be associated with GADA or IA2A in people with T1D. Our findings suggest that HLA-DRB1^∗03/DQB1^∗02 and HLA-DRB1^∗04/DQB1^∗03 might play an important role in the development of GADA and IA2A, respectively.

Clinical features, biochemistry and HLA-DRB1 status in children and adolescents with diabetes in Dhaka, Bangladesh

AIMS

Little information is published on diabetes in young people in Bangladesh. We aimed to investigate the demographic, clinical, and biochemical features, and HLA-DRB1 alleles in new cases of diabetes affecting Bangladeshi children and adolescents <22 years of age.

METHODS

The study was conducted at Bangladesh Institute of Research and Rehabilitation of Diabetes, Endocrine and Metabolic Disorders (BIRDEM) in Dhaka. One hundred subjects aged <22 years at diagnosis were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, and autoantibodies against glutamic acid decarboxylase 65 (GADA) and islet antigen-2 (IA-2A) were measured. High-resolution DNA genotyping was performed for HLA-DRB1.

RESULTS

Eighty-four subjects were clinically diagnosed as type 1 diabetes (T1D), seven as type 2 diabetes (T2D), and nine as fibrocalculous pancreatic disease (FCPD). Of the 84 with T1D, 37 (44%) were males and 47 (56%) females, with median age at diagnosis 13 years (y) (range 1.6-21.7) and peak age at onset 12-15 years. 85% of subjects were assessed within one month of diagnosis and all within eleven months. For subjects diagnosed with T1D, mean C-peptide was 0.46 ± 0.22 nmol/L (1.40 ± 0.59 ng/mL), with 9 (10.7%) IA-2A positive, 22 (26%) GADA positive, and 5 (6%) positive for both autoantibodies. Analysis of HLA-DRB1 genotypes revealed locus-level T1D association (p = 6.0E-05); DRB1*04:01 appeared predisposing (p < 3.0E-06), and DRB1*14:01 appeared protective (p = 1.7E-02).

CONCLUSIONS

Atypical forms of T1D appear to be more common in young people in Bangladesh than in European populations. This will be helpful in guiding more specific assessment at onset and potentially, expanding treatment options.

Clinical features, biochemistry and HLA-DRB1 status in youth-onset type 1 diabetes in Pakistan

Published information on diabetes in Pakistani youth is limited. We aimed to investigate the demographic, clinical, and biochemical features, and HLA-DRB1 alleles in new cases of diabetes affecting children and adolescents <22 years of age. The study was conducted at Baqai Institute of Diabetology and Endocrinology in Karachi from June 2013-December 2015. One hundred subjects aged <22 years at diagnosis were enrolled. Demographic characteristics, clinical information, biochemical parameters (blood glucose, HbA1c, C-peptide, glutamic acid decarboxylase 65 (GAD65) and islet antigen 2 (IA-2) autoantibodies) were measured. DNA from 100 subjects and 200 controls was extracted and genotyped for HLA-DRB1 using high-resolution genotyping technology. Ninety-nine subjects were clinically diagnosed as type 1 diabetes (T1D) and one as type 2 diabetes (T2D). Of the 99 with T1D, 57 (57.6%) were males and 42 (42.4%) females, with mean age at diagnosis 11.0 ± 5.2 years (range 1.6-21.7 years) and peaks at six and fifteen years. Fifty-seven subjects were assessed within one month of diagnosis and all within eleven months. For the subjects diagnosed as T1D, mean C-peptide was 0.63 ± 0.51 nmol/L (1.91 ± 1.53 ng/mL), with 16 (16.2%) IA2 positive, 53 (53.5%) GAD-65 positive, and 10 (10.1%) positive for both autoantibodies. In T1D patients, the allele DRB1*03:01 demonstrated highly significant T1D association (p < 10-16), with no apparent risk conferred by DRB1*04:xx alleles. CONCLUSIONS: Heterogeneous forms of T1D appear more common in children and youth in Pakistan than in European populations. Individual understanding of such cases could enable improved management strategies and healthier outcomes.

Peripheral blood mononuclear cells of patients with latent autoimmune diabetes secrete higher levels of pro- & anti-inflammatory cytokines compared to those with type-1 diabetes mellitus following in vitro stimulation with β-cell autoantigens

Background & objectives:

Type-1 diabetes mellitus (T1DM) and latent autoimmune diabetes in adults (LADA) share similar pathological features but differ in age of onset and progression. There is a scarcity of information on differences in CD4+ T-cell responses, particularly, cytokine secretion, between the two forms of autoimmune diabetes. Here proliferative potential and concentration of pro- and anti-inflammatory cytokines secreted by peripheral blood mononuclear cells (PBMCs) of T1DM and LADA patients were compared, after in vitro stimulation with β-cell autoantigens.

Methods:

A total of 19 patients with LADA, 37 with T1DM and 20 healthy controls were compared on the basis of lymphocyte proliferation and secretion of pro- and anti-inflammatory cytokines belonging to different T-helper types after in vitro stimulation of PBMCs with insulin and glutamic acid decarboxylase 65 (GAD65).

Results:

Following insulin stimulation, LADA group secreted higher concentration of interleukin-17 (IL-17) (P=0.02) and had higher proportion of interferon gamma (IFN-γ) secretors (P<0.001) than T1DM group. Post-GAD65 stimulation, higher proportion of LADA patients secreted IL-23 than T1DM group (P=0.02). Proportion of responders, as well as levels of secreted IL-10, were significantly higher in LADA than T1DM group, following stimulation with both insulin (P=0.01) and GAD65 (P=0.03). A significant positive correlation was observed between body mass index and IL-17 levels (r=0.41, P=0.04) and fasting plasma C-peptide with IL-10 levels (r=0.37, P=0.04).

Interpretation & conclusions:

There are differences in the portfolio of cytokine secretion in diabetic subjects with varying rates of β-cell destruction as LADA subjects secrete higher levels of both pro- and anti-inflammatory cytokines on exposure to β-cell autoantigens, thus highlighting another distinguishing feature in the pathophysiology of the two forms of autoimmune diabetes.

Thyroid profile and autoantibodies in Type 1 diabetes subjects: A perspective from Eastern India

CONTEXT

There has been a rise in the incidence of type 1 diabetes mellitus (T1DM) in India. The prevalence of thyroid autoantibodies and thyroid dysfunction is common in T1DM.

AIMS

The aim of this study is to determine the incidence of thyroid dysfunction and thyroid autoantibodies in T1DM subjects, without any history of thyroid disease, and the prevalence of glutamic acid decarboxylase (GAD) antibody, Islet antigen-2 antibody (IA2), thyroid peroxidase (TPO), and thyroglobulin autoantibodies (Tg-AB) in T1DM subjects.

SETTINGS AND DESIGN

This was a cross-sectional clinical-based study.

SUBJECTS AND METHODS

Fifty subjects (29 males, 31 females) with T1DM and without any history of thyroid dysfunction were included in the study. All subjects were tested for GAD antibody, IA2 antibody, TPO antibody, thyroglobulin antibody, free thyroxine, and thyroid-stimulating hormone.

STATISTICAL ANALYSIS USED

A Chi-square/pooled Chi-square test was used to assess the trends in the prevalence of hypothyroidism. A two-tailed P < 0.05 was considered statistically significant.

RESULTS

The mean age of the subjects was 23.50 years. 9.8% of subjects were below the age of 12 years, 27.45% of subjects were of age 12-18 years, 37.25% of subjects were of age 19-30 years, and 25.49% of subjects were above 30 years. 78% were positive autoantibody for GAD, 30% for IA-2, 24% for TPO, and 16% were positive for Tg-AB. A total of 6.0% of T1DM subjects had evidence of clinical hypothyroidism, but the prevalence of subclinical hyperthyroidism (SCH) varied from 32% to 68.0% for we considered different definitions of SCH as advocated by different guidelines. All subjects with overt hypothyroidism had positive GAD and thyroid autoantibodies. One (2%) subject had clinical hyperthyroidism with strongly positive GAD, TPO, and Tg-AB.

CONCLUSIONS

We found a high prevalence of GAD, IA2, TPO, and Tg-AB in our T1DM subjects. A substantial proportion of our subjects had undiagnosed thyroid dysfunction with a preponderance of subclinical hypothyroidism. All T1DM subjects with overt hypothyroidism or hyperthyroidism had positive GAD and thyroid autoantibodies. The high prevalence of undiagnosed thyroid dysfunction highlights the importance of regular thyroid screening in T1DM subjects.

Prevalence of celiac disease in Indian children with type 1 diabetes

BACKGROUND

Type 1 diabetes (T1D) patients are at an increased risk of having celiac disease (CD). We evaluated the prevalence and clinical profile of CD in children and adolescents with T1D and reviewed the Indian literature to determine prevalence and reasons for variability.

METHODS

In this cross-sectional study, subjects with T1D were prospectively evaluated with a demographic and gastrointestinal (GI) questionnaire, human IgA-tissue transglutaminase (IgA-tTGA), and endoscopic duodenal biopsy in serology positive patients. Studies evaluating prevalence of CD in T1D from India were reviewed.

RESULTS

Fourteen (13.6 %) of the 103 (52 boys, 13 years [2-20]) T1D patients were IgA-tTGA (182 U [47-300]) positive and 3.8 % (4/103) had villous atrophy on histology. Subjects with T1D and CD (n = 4) were younger at onset of T1D (32.5 ± 12.6 vs. 110.5 ± 53.8 months; p < 0.005) and more often had GI symptoms (pain abdomen [2/4 vs. 6/89; p = 0.01], stool frequency of 2-3/day [3/4 vs. 38/89; p = 0.004]) than screen negative T1D (n = 89). Growth and glycemic control were not different between the groups. In the 7 Indian studies involving 915 children and adults, 13.8 % (8 % to 17.8 %) T1D were serology positive. Prevalence of CD was reported as 6.9 % (2.3 % to 11.1 %), but only 3.1 % (2.3 % to 4.2 %) had villous atrophy on histology.

CONCLUSIONS

Potential CD and CD were present in 13.6 % and 3.8 % children with T1D respectively. T1D with CD have onset of diabetes at younger age and were more often symptomatic than screen negative T1D.

The seroprevalence of immunoglobulin A transglutaminase in type 1 diabetic patients of South Indian origin

CONTEXT

Celiac disease (CD) is a commonly encountered autoimmune condition in patients with type 1 diabetes (T1D). There is sparse data on the seroprevalence of immunoglobulin A (IgA) transglutaminase (tTG) in T1D patients of South Indian origin.

AIMS

To detect the prevalence of IgA tTG in T1D patients of South Indian origin. To evaluate the relation between the presence of autoimmunity and metabolic control and complications of diabetes.

MATERIALS AND METHODS

We conducted a cross-sectional study on 258 T1D patients. All the patients were subjected to biochemical tests and evaluated for microvascular complications. IgA tTG was estimated by ELISA. IgA tTG levels >40 AU/ml was considered positive.

RESULTS

Of the 258 participants, 12 (4.65%) were found to be positive for IgA tTG antibodies. Distribution of IgA positivity was equal in both sexes. There was a significant negative correlation of IgA tTG positivity with hemoglobin and glycated hemoglobin (HbA1c).

CONCLUSIONS

The seropositivity of CD in South Indian patients with T1D has been observed to be 4.68%. This is much lower compared to studies from North India. This can be explained by both the genetic and dietary factors. The seropositivity correlated negatively with hemoglobin and HbA1c.

Prevalence of Beta-Cell, Thyroid and Celiac Autoimmunity in North Indian Children with Recent Onset Type 1 Diabetes (T1D)

There is wide variation in the prevalence of pancreatic and other major autoantibodies in different patient populations of Type 1 diabetes (T1D) across continents and even within countries. The data on frequency of associated autoimmunity Indian children with T1D is limited. A retrospective record review of 310 children aged 7.28±3.3 y (range 0.7-15 y) with recently diagnosed T1D attending our Pediatric Diabetes Clinic between April 2004 to September 2014, showed positivity for anti-GAD65, anti-IA2b, anti-TPO and anti-tTGA of 50% (64/128), 16% (12/72), 18.7% (23/123) and 22% (47/212) respectively. The male:female ratio in patients with anti-GAD, anti-TPO and anti-tTG positivity was 1.3, 0.7 and 0.6 respectively. In conclusion, our patient cohort exhibited a moderate prevalence of anti-GAD 65, low prevalence of anti-TPO and high prevalence of anti-tTGA autoantibodies as compared to previous reports. Male preponderance was noted in children with GAD65 positivity.

Zinc transporter-8 autoantibodies can replace IA-2 autoantibodies as a serological marker for juvenile onset type 1 diabetes in India

INTRODUCTION

Zinc transporter-8 (ZnT8) is an islet cell secretory granule membrane protein recently identified as an autoantigen in type 1 diabetes (T1D). The aim of this study was to estimate the prevalence of antibodies to ZnT8 (ZnT8A) in juvenile onset T1D and to determine the utility of ZnT8A as an independent marker of autoimmunity either alone in antibody-negative subjects or in conjunction with glutamic acid decarboxylase (GAD) and insulinoma-2 antigen antibodies (GADA and IA2A).

RESEARCH DESIGN

ZnT8A, GADA, and IA2A were measured in sera of consecutive T1D patients (n = 88, age range 2-18 years) within 4 years of diagnosis and 88 sex-matched controls.

RESULTS

The prevalences of GADA, ZnT8a, and IA2A were 64.7%, 31.8% and 19.3%, respectively. In newly diagnosed patients, the frequency of ZnT8A was 45%. ZnT8A were positive in 26% of patients negative for both GADA and IA2A. IA2A were positive only in two patients who were negative for other two antibodies. Combined use of ZnT8A and GADA could detect 97% of antibody positive patients. In receiver operating characteristic (ROC) analysis, the performances of GADA and ZnT8As were better than that of IA2A; and AUCs of GADA, ZnT8A, and IA2A for the prediction of T1D were 0.8, 0.65, and 0.59, respectively.

CONCLUSIONS

ZnT8A complements GADA and increases the diagnostic sensitivity for detection of autoimmunity in juvenile-onset T1D. Inclusion of ZnT8A increases the proportion of patients with antibody positivity to nearly 80%. ZnT8A can replace IA2A as a serological marker for autoimmunity in Indian T1D patients without loss of sensitivity and specificity.

Approaches in type 1 diabetes research: A status report

Type 1 diabetes is a multifactorial disease with an early age of onset, in which the insulin producing beta cell of the pancreas are destroyed because of autoimmunity. It is the second most common chronic disease in children and account for 5% to 10% of all diagnosed cases of diabetes. India is having an incidence of 10.6 cases/year/100,000, and recent studies indicate that the prevalence of type 1 diabetes in India is increasing. However in view of poor health care network, there is no monitoring system in the country. Of the 18 genomic intervals implicated for the risk to develop type 1 diabetes, the major histocompatibility complex (MHC) region on chromosome 6p21.31 has been the major contributor estimated to account for 40-50%, followed by 10% frequency of INS-VNTR at 5' flanking region of the insulin gene on chromosome 11p15.5. However, population studies suggest that > 95% of type 1 diabetes have HLA-DR3 or DR4, or both, and in family studies, sibling pairs affected with type 1 diabetes have a non-random distribution of shared HLA haplotypes. As predisposing genetic factors such as HLA alleles are known, immunological interventions to prevent type 1 diabetes are of great interest. In the present study we have reviewed the status of molecular genetics of the disease and the approaches that need to be adopted in terms of developing patient and suitable control cohorts in the country.

Genetic determinants of Type 1 diabetes: immune response genes

Type 1 diabetes (T1D) is a polygenic autoimmune disease. Susceptibility to T1D is strongly linked to a major genetic locus that is the MHC, and several other minor loci including insulin, cytotoxic T-lymphocyte-associated antigen-4, PTPN22 and others that contribute to diabetes risk in an epistatic way. We have observed that there are three sets of DR3-positive autoimmunity-favoring haplotypes in the north-Indian population, including B50-DR3, B58-DR3 and B8-DR3. The classical Caucasian autoimmunity favoring AH8.1 (HLA-A1-B8-DR3) is rare in the Indian population, and has been replaced by a variant AH8.1v, which differs from the Caucasian AH8.1 at several gene loci. Similarly, there are additional HLA-DR3 haplotypes, A26-B8-DR3 (AH8.2), A24-B8-DR3 (AH8.3), A3-B8-DR3 (AH8.4) and A31-B8-DR3 (AH8.5), of which AH8.2 is the most common. The fact that disease-associated DR3-positive haplotypes show heterogeneity in different populations suggests that these might possess certain shared components that are involved in the development of autoimmunity.

Autoantibodies to GAD65 and IA-2 antibodies are increased, but not tissue transglutaminase (TTG-Ab) in type 2 diabetes mellitus (T2DM) patients from South India

The frequency of autoantibody-positve T2DM patients identified as LADA was shown to be high in T2DM patients from Eastern India. In this study, we measured autoantibodies to GAD65, IA-2, and TTG in T2DM patients from Southern India. Our results show that either GAD65 or IA-2 was present in 30% of T2DM patients (n = 155) and in 3% of controls for GAD65 and 1% of controls for IA-2 (n = 105). TTG-Ab was not increased in T2DM patients compared to controls. Our results suggest that LADA is more frequent in Southern Indians than in European Caucasians, but not as high as in Eastern Indians.