Impact of CYP2C9*2 and *3 polymorphisms on valproate-associated adverse drug reactions in individuals living with epilepsy: a case-control study

Epilepsy is characterized by repeated seizure activity. Valproate, a commonly used antiepileptic drug, shows large inter-individual variation in plasma valproic levels and causes many adverse drug reactions. Aim: To find the influence of CYP2C9*2 and *3 polymorphisms on valproate-associated adverse drug reactions and plasma valproic acid levels in people with epilepsy. Methods: We recruited 158 people with epilepsy (79 cases and 79 controls) from an epilepsy clinic. Steady-state plasma valproic acid levels were measured using liquid chromatography-mass spectrometry and genotyping of CYP2C9 variants was carried out with helps of RT-PCR. Results: The presence of a mutant heterozygous genotype showed an odds ratio (OR) of 2.82 (95% CI: 1.10-7.24) and the adjusted OR was 5.39 (95% CI: 1.69-17.16). There was no significant difference in steady-state plasma valproate concentration between genotypes. Conclusion: The presence of a mutant heterozygous CYP2C9 genotype possesses five-times the risk of developing adverse drug reactions to valproate in people with epilepsy.

Frequency and association of self-reported oral cancer among individuals with type 2 diabetes at a tertiary care diabetes centre in South India - A retrospective study

AIM

To assess the frequency of self-reported oral cancer and associated factors among individuals with type 2 diabetes (T2D) at a tertiary care diabetes centre in South India.

METHODS

Individuals with T2D who reported that they had oral cancer were included from the Diabetes Electronic Medical Records (DEMR) database. To assess the association of oral cancer with T2D, a retrospective nested case-control study design was adopted. Individuals with T2D and oral cancer diagnosed after the diagnosis of T2D (n = 78) were considered 'cases', while T2D without oral cancer were considered 'controls' (312) [in a ratio of 1:4 for cases and controls]. The cases and controls were matched for age, gender and duration of diabetes. Logistic regression was used to model predictors of oral cancer in T2D patients.

RESULTS

Oral cancer was reported in 78 out of 379,138 (0.02%) individuals with T2D registered at the centre. Logistic regression analysis showed that a HbA1c value ≥ 9% had a significant association with oral cancer with an odds ratio of 2.3 (95% CI: 1.2-4.6) after adjusting for confounding factors. Among individuals with T2D, higher frequency of oral cancer prevalence and risk was observed among those who used any form of tobacco (32.6%, OR = 2.52, 95% CI: 1.5-4.3), consumed alcohol (29.2%, OR = 2.01, 95% CI: 1.2-3.3), and those with hypertension (23.9%, OR = 2.05, 95% CI: 1.2-3.6) and hypertriglyceridemia (24.7%, OR = 1.66, 95% CI: 1.01-2.7). Significant independent predictors of oral cancer among T2D were tobacco use (OR = 2.06, 95% CI: 1.1-4.00), high HbA1c (OR = 1.3, 95% CI: 1.03-1.5), hypertension (OR = 2.3, 95% CI: 1.3-4.2) and insulin use (OR = 1.8, 95% CI: 1.03-3.2).

CONCLUSIONS

Regular dental check-ups as part of the follow-up for individuals with T2D will identify and diagnose oral cancer earlier. Further research is required to assess the physiological and biological mechanisms leading to oral cancer in individuals with T2D.

Targeted Exome Sequencing in South Indian patients with Familial Hypercholesterolemia

BACKGROUND

Familial hypercholesterolemia (FH) is an autosomal dominant genetic disorder with elevated LDL-C levels which can ultimately lead to premature Coronary Artery Disease (CAD).

OBJECTIVES

In presence of limited genetic data on FH in India, the present study was aimed to determine the mutation spectrum in Indian FH patients using a targeted exome sequencing.

METHODS

54 FH cases (31 index cases + 23 extended family members) were categorized according to Dutch Lipid Clinic Network Criteria (DLCNC). Targeted exome sequencing was performed using 23 gene panel associated with lipid metabolism.

RESULTS

All subjects showed the presence of family history of CAD, 38(70%) patients had corneal arcus whereas only 06(11%) subjects had xanthomas. As per the DLCNC, definite, probable, possible and unlikely FH were 48%, 30%, 11% and 11% respectively. Mutations were observed in 12 of the 23 gene panel with CETP, APOA5, EPHX2 and SREBP2 genes were identified for the first time in Indian FH patients. All 19 mutations including a novel frame-shift mutation in LDLR gene were reported for the first time in Indian FH patients. These mutations were identified in 28(52%) subjects and interestingly ∼73% of the clinically identified FH patients didn't harbour mutations in FH classical genes (LDLR, ApoB, PCSK9).

CONCLUSION

This is the first study in the South Indian FH patients to perform targeted exome sequencing. Absence of mutations in the FH classical genes strongly indicates the polygenic nature of FH, further underscoring the importance of targeted exome sequencing for identifying mutations in genetically diverse Indian population.

Evaluation of the effect of impaction on the mineralization of mandibular third molars and forensic age estimation in a sample of south Indian children

Assessment of third molar mineralization is a basic forensic odontological method available for age estimation in children and adolescents. Due to their protracted development into the late adolescence, their development has become the subject of interest and acquired great forensic importance. It is clearly evident in the literature that impaction factor has an influence on the rate of maturation of the third molars. In this regard, the present study was undertaken to test the relationship between impaction and its concomitant effect on the mineralization of the third molar and forensic age estimation. A total of 520 digital orthopantomograms (OPG) of 260 males and 260 females of south Indian origin were assessed retrospectively. Maturation of the third molars (I3M) was assessed using the method of Cameriere et al. (Int J Leg Med 122 (6):493-497, 2008). Impaction status was determined according to the position of lower right and left third molars in relation to the long axis of the second molars. Out of the total sample, 68.1% of lower left third molars and 71.2% of lower right molars were impacted. Statistical measures for I3M were calculated in the males and females for both impacted and non-impacted third molars. It was ascertained that the mean age and I3M values were higher in impacted third molars, indicating the slower rate of maturation than non-impacted ones. The sensitivity and specificity of the test (I3M < 0.08) was 96.2% and 72.4% for non-impacted third molars and 46.2% and 87% for impacted third molars, respectively. Our findings indicate that the cut-off value of I3M < 0.08 resulted in greater number of age misclassifications (false negatives) for impacted molars, highlighting the need for new cut-off value of I3M to meet the legal standards. It was concluded that the mineralization of impacted third molars was slower compared to non-impacted ones in south Indian males and females. Further studies are warranted to validate these findings among a larger and more diverse sample.

Legal age determined by a new threshold value of third molar maturity index in subjects with impacted mandibular third molars: An orthopantomographic study in south Indian adolescents

Third molars are one of the few biological markers available for age estimation in juveniles, especially for the estimation of the 18-year-age threshold. Literature has indicated that impaction has an influence on the development of third molars, which could possibly result in age misclassifications. The present study is intended to identify an alternative cut-off value of the third molar maturity index (I3M) in impacted mandibular third molars and also to evaluate its applicability in estimating the major (≥ 18 years)/minor (< 18 years) status. A total of 1330 digital orthopantomograms (OPGs) of 665 male and 665 female south Indian adolescents aged from 15 to 22 years were collected and assessed. Eight hundred forty OPGs (63.1%) represented test sample, and 490 OPGs (36.9%) represented validation sample. I3M was measured for the total sample. Logistic regression, receiver operating characteristic (ROC) curve analysis, and Youden's index were used to test the performance of the method in the test sample. An alternative cut-off value of I3M < 0.17 was established for the highest value of the Youden's index of 0.598 for both sexes. When tested in validation sample, it has resulted in sensitivity and specificity values of 0.91 (95% CI; 0.86-0.95) and 0.90 (95% CI; 0.78-0.91) in males and 0.86 (95% CI; 0.80-0.92) and 0.90 (95% CI; 0.83-0.95) in females. In conclusion, cut-off value of I3M < 0.17 could accurately discriminate adults from minors with impacted mandibular third molars. However, more work is needed to be done among a more diverse sample to confirm these findings.

Prevalence of vitamin B12 deficiency in South Indians with different grades of glucose tolerance

AIMS

To determine the prevalence of vitamin B₁₂ deficiency in an urban south Indian population in individuals with different grades of glucose tolerance.

METHODS

A total of 1500 individuals [900 normal glucose tolerance (NGT), 300 prediabetes and 300 type 2 diabetes (T2DM)] who were not on vitamin B₁₂ supplementation were randomly selected from the Chennai Urban Rural Epidemiological Study (CURES) follow-up study. Anthropometric, clinical and biochemical investigations, which included vitamin B₁₂, insulin, homocysteine, HbA1c and serum lipids, were measured. Vitamin B₁₂ ≤ 191 pg/ml was defined as absolute vitamin B₁₂ deficiency and vitamin B₁₂ > 191 pg/ml and ≤ 350 pg/ml as borderline deficiency.

RESULTS

The mean levels of vitamin B₁₂ significantly decreased with increasing degrees of glucose tolerance (NGT 444 ± 368; prediabetes 409 ± 246; T2DM 389 ± 211 pg/ml, p = 0.021). The prevalence of absolute vitamin B₁₂ deficiency was 14.9% while 37.6% had borderline deficiency. The prevalence of absolute vitamin B₁₂ deficiency was significantly higher among individuals with T2DM (18.7%) followed by prediabetes (15%) and NGT(13.7%) [p for trend = 0.05]. The prevalence of vitamin B₁₂ significantly increased with age (p < 0.05) and in those with abdominal obesity (p < 0.001). Men and vegetarians had twice the risk of vitamin B₁₂ deficiency compared to women and non-vegetarians, respectively. Among individuals with NGT, prediabetes and T2DM, vitamin B₁₂ negatively correlated with homocysteine.

CONCLUSION

This study reports that the levels of vitamin B₁₂ decreased with increasing severity of glucose tolerance.

Association of rs11643718 SLC12A3 and rs741301 ELMO1 Variants with Diabetic Nephropathy in South Indian Population

This study reports on the association of genetic variants selected from previous genome-wide association studies for type 2 diabetic nephropathy in south Indians. Eight variants were genotyped in 601 type 2 diabetic subjects without nephropathy (DM) and 583 type 2 diabetic subjects with nephropathy (DN) by MassARRAY. The minor allele frequencies of rs11643718 SLC12A3 variant and rs741301 ELMO1 variant were significantly different between DM and DN groups (P = 0.029 and 0.016, respectively). A combined analysis showed that the subjects carrying the risk genotypes of both these variants (GG of rs11643718 + AG/AA of rs741301) had a significant association with DN with an odds ratio [adjusted for age, sex, Body Mass Index (BMI), HbA1c, and systolic Blood Pressure (BP)] of 1.73 (1.30-2.30, P = 1.72 × 10^-4 ) as compared to subjects carrying all other genotype combinations. This is the first study to report a significant association of the SLC12A3 rs11643718 and ELMO1 rs741301 (Single nucleotide Polymorphism) SNPs with diabetic nephropathy in south Indians.

Influence of dihydrofolate reductase gene polymorphisms rs408626 (-317A>G) and rs442767 (-680C>A) on the outcome of methotrexate-based maintenance therapy in South Indian patients with acute lymphoblastic leukemia

PURPOSE

The most common cause of treatment failure in acute lymphoblastic leukaemia (ALL) is the relapse. Genetic polymorphisms of dihydrofolate reductase (DHFR) enzyme affect the response to methotrexate (MTX) treatment. Inter-individual variability exists in the distribution of DHFR variants, and they influence MTX treatment outcome. To the best of our knowledge, there are no genetic studies reported from India, which have explored the influence of DHFR variants on the outcome of MTX treatment. Therefore, we aim to study the influence of DHFR rs408626 (-317A>G) and rs442767 (-680C>A) variants on ALL outcome in South Indian patients.

METHODS

A total of 70 ALL patients who were on MTX-based maintenance therapy were recruited for the study. DNA was extracted from leukocytes, and genotyping was done by real-time PCR.

RESULTS

The DHFR-317GG genotype was associated with the increased risk of relapse in patients with ALL (relative risk 2.25, 95% confidence interval (CI) 1.38 to 3.6, p = 0.02). DHFR-317AA and -680CA genotypes were found to be associated with severe leucopenia (p < 0.05). In Cox regression model, -317GG genotype was found to have lower relapse-free survival (hazard ratio (HR) 2.56, 95% CI 1.06 to 6.19, p = 0.03) and overall survival (HR 3.72, 95% CI 1.44 to 9.65, p = 0.007). Similarly, patients with white blood cell (WBC) count >50,000 cells/mm(3) were also found to have lower relapse-free survival (HR 2.20, 95% CI 1.10 to 4.79, p = 0.04) and overall survival (HR 3.30, 95% CI 1.45 to 7.53, p = 0.004).

CONCLUSION

The GG genotype of DHFR-317A>G variant is associated with increased risk of ALL relapse and lower overall survival in South Indian population. Both variants of DHFR (-317 AA and -680 CA) are found to be associated with severe leucopenia caused by MTX.

Accuracy of Demirjian's 8 teeth method for age prediction in South Indian children: A comparative study

Introduction:

Demirjian's method of tooth development is most commonly used to assess age in individuals with emerging teeth. However, its application on numerous populations has resulted in wide variations in age estimates and consequent suggestions for the method's adaptation to the local sample. Original Demirjian's method utilized seven mandibular teeth, to which recently third molar is added so that the method can be applied on a wider age group. Furthermore, the revised method developed regression formulas for assessing age. In Indians, as these formulas resulted in underestimation, India-specific regression formulas were developed recently. The purpose of this cross-sectional study was to evaluate the accuracy and applicability of original regression formulas (Chaillet and Demirjian 2004) and India-specific regression formulas (Acharya 2010) using Demirjian's 8 teeth method in South Indian children of age groups 9–20 years.

Methods:

The present study consisted of 660 randomly selected subjects (330 males and 330 females) were in the aged ranging from 9 to 20 years divided into 11 groups according to their age. Demirjian's 8 teeth method was used for staging of teeth.

Results:

Demirjian's method underestimated the dental age (DA) by 1.66 years for boys and 1.55 years for girls and 1.61 years in total. Acharya's method over estimated DA by 0.21 years for boys and 0.85 years for girls and 0.53 years in total. The absolute accuracy was better for Acharya's method compared with Demirjian method.

Conclusion:

This study concluded that both the Demirjian and Indian regression formulas were reliable in assessing age making Demirjian's 8 teeth method applicable for South Indians.

Accuracy of four dental age estimation methods in southern Indian children

INTRODUCTION

For various forensic investigations of both living and dead individuals, the knowledge of the actual age or date of birth of the subject is of utmost importance. In recent years, age estimation has gained importance for a variety of reasons, including identifying criminal and legal responsibility, and for many other social events such as birth certificate, marriage, beginning a job, joining the army and retirement. Developing teeth are used to assess maturity and estimate age in number of disciplines; however the accuracy of different methods has not been assessed systematically. The aim of this study was to determine the accuracy of four dental age estimation methods.

MATERIALS AND METHODS

Digital Orthopantomographs (OPGS) of South Indian children between the ages of 6 and 16 y who visited the department of Department of Oral medicine and Radiology of GITAM Dental College, Visakhapatnam, Andhra Pradesh, India with similar ethnic origin were assessed. Dental age was calculated using Demirjian, Willems, Nolla, and adopted Haavikko methods and the difference between estimated dental age and chronological age were compared with paired t-test and Wilcoxon signed rank test.

RESULTS

An overestimation of the dental age was observed by using Demirjian and Nolla methods (0.1±1.63, 0.47±0.83 years in total sample respectively) and an underestimation of dental age was observed by using Willems and Haavikko methods (-0.4±1.53, -2.9±1.41 years respectively in total sample).

CONCLUSION

Nolla's method was more accurate in estimating dental age compared to other methods. Moreover, all the four methods were found to be reliable in estimating age of individuals of unknown chronological age in South Indian children.

Influence of SLC22A1 rs622342 genetic polymorphism on metformin response in South Indian type 2 diabetes mellitus patients

Metformin is an oral antidiabetic drug, commonly used for treating type 2 diabetes mellitus (T2DM) patients. It is transported into the hepatocytes by polyspecific organic cation transporter 1, which is encoded by the gene SLC22A1. It has been hypothesized that genetic variations of SLC22A1 gene will influence inter-individual variation in glucose lowering efficacy of metformin. Previous studies have demonstrated this in other populations with conflicting results, but it remains to be elucidated in Indian population. Henceforth, the objective of the study was to evaluate the impact of SLC22A1 rs622342 gene polymorphism on the clinical efficacy of metformin in South Indian T2DM patients. A total of 122 newly detected, treatment naive T2DM patients of either sex were included in this study. The patients were started on metformin monotherapy and followed up for 12 weeks. Genotype was determined using qRT-PCR. Before and after treatment with metformin, body mass index (BMI), serum lipid profile, glycated hemoglobin (HbA1c), fasting and postprandial glucose level, and blood pressure (BP) were measured. The study cohort mean age was 49.57 ± 9.88 years. Of the 122 T2DM patients, 93 were classified as responders and 29 as non-responders based on fall in HbA1c levels. Interestingly, carriers of one variant allele 'C' (AC) of rs622342 polymorphism were less among the responders than those who did not (44.8 vs. 22.6 %). The response was even lesser (13.8 vs. 4.3 %) in carriers of two copies of "C" allele (CC). On the contrary, patients with two copies of allele 'A' (AA) had 5.6 times greater chance of responding to metformin treatment. A similar trend was observed when the proportion was analyzed under different genetic models (OR 3.85, 95 % CI 1.61-9.19 for dominant; OR 3.56, 95 % CI 0.83-15.26 for recessive; OR 0.35, 95 % CI 0.14-0.86 for over-dominant; and OR 4.10, 95 % CI 1.78-9.43 for additive). Further, metformin showed significant beneficial effects on BMI, HbA1c, FPG, PPG, lipid parameters and BP. These data suggest that the allele and genotypes of SLC22A1 rs622342 gene polymorphism were associated with the therapeutic efficacy of metformin in South Indian patients with T2DM.

Association of serum adiponectin with diabetic microvascular complications among south Indian type 2 diabetic subjects - (CURES-133)

OBJECTIVES

To assess the association of serum adiponectin and microvascular complications of diabetes in an urban south Indian type 2 diabetic population.

DESIGN AND METHODS

Diabetic subjects [n=487] were included from Chennai Urban Rural Epidemiology Study (CURES). Four-field stereo retinal color photography was done and diabetic retinopathy (DR) was classified as non-proliferative DR (NPDR) or proliferative DR (PDR) according to the Early Treatment Diabetic Retinopathy Study grading system. Sight threatening DR (STDR) was defined as the presence of NPDR with diabetic macular edema, and/or PDR. Neuropathy was diagnosed if vibratory perception threshold of the great toe using biothesiometry exceeded ≥20V. Nephropathy was diagnosed if urinary albumin excretion (UAE) was ≥30μg/mg creatinine. Serum total adiponectin levels were measured by radioimmunoassay.

RESULTS

Subjects with any microvascular complications had significantly higher levels of adiponectin levels compared to those without the complications (geometric mean: 6.1 vs. 5.3μg/mL, p=0.004). The adiponectin level was significantly higher in subjects with DR (6.8 vs. 5.5μg/mL, p=0.004) and neuropathy (5.6 vs. 6.5μg/mL, p=0.024) compared to those without. Adiponectin levels were not significantly different in subjects with and without nephropathy. Serum adiponectin levels increased with the severity of DR [No DR - 5.5μg/mL; NPDR without DME - 6.5μg/mL; STDR - 8.3μg/mL, p=0.001]. Regression analysis revealed adiponectin to be associated with microvascular disease (presence of neuropathy and/or retinopathy and/or nephropathy) (OR: 1.44, 95% CI: 1.01-2.06, p=0.049) even after adjusting for age, gender, BMI, HbA1c, diabetes of duration, serum cholesterol and triglycerides, hypertension and medication status.

CONCLUSION

In Asian Indians with type 2 diabetes, serum adiponectin levels are associated with microvascular complications and also with the severity of retinopathy.

Drug-induced gingival overgrowth: the genetic dimension

Background:

Currently, the etiology of drug-induced gingival overgrowth is not entirely understood but is clearly multifactorial. Phenytoin, one of the common drugs implicated in gingival enlargement, is metabolized mainly by cytochrome P450 (CYP)2C9 and partly by CYP2C19. The CYP2C9 and CYP2C19 genes are polymorphically expressed and most of the variants result in decreased metabolism of the respective substrates.

Aims:

The present study was undertaken to investigate the influence of the CYP2C9*2 and *3 variant genotypes on phenytoin hydroxylation in subjects diagnosed with epilepsy from South India, thus establishing the genetic polymorphisms leading to its defective hydroxylation process.

Materials and Methods:

Fifteen epileptic subjects, age 9 to 60 years were included in the study. Among the study subjects, 8 were males and 7 were females. Genomic DNA was extracted from patients’ blood using Phenol-chloroform method and genotyping was done for CYP2C9 using customized TaqMan genotyping assays on a real time thermocycler, by allelic discrimination method. The genetic polymorphisms *1, *2 and *3 on CYP2C9 were selected based on their function and respective allele frequencies in Asian subcontinent among the Asian populations.

Results:

CYP2C9*1*2 and CYP2C9*3/*3 were identified with equal frequency in the study population. There were seven subjects with CYP2C9*1/*2 genotype (heterozygous mutant), one subject with CYP2C9*1/*1 (wild type) and seven study subjects with CYP2C9*3/*3 (homozygous mutant).

Conclusion:

The results obtained in the present study will be helpful in the medical prescription purposes of phenytoin, and a more personalized patient approach with its administration can be advocated.

Inter and intra ethnic variation of vitamin K epoxide reductase complex and cytochrome P450 4F2 genetic polymorphisms and their prevalence in South Indian population

BACKGROUND:

Genetic variation in the vitamin K epoxide reductase complex (VKORC1) and cytochrome P450 4F2 (CYP4F2) genes were found to be strongly associated with the oral anticoagulant (OA) dose requirement. The distribution of genetic variation in these two genes was found to show large inter- and intra-ethnic difference.

MATERIALS AND METHODS:

A total of 470 unrelated, healthy volunteers of South Indians of either sex (age: 18-60 years) were enrolled for the study. A 5 ml of venous blood was collected and the genomic deoxyribonucleic acid (DNA) was extracted by using phenol-chloroform extraction method. Real-time quantitative polymerase chain reaction (RT-PCR) method was used for genotyping.

RESULTS:

The variant allele frequencies of VKORC1 rs2359612 (T), rs8050894 (C), rs9934438 (T) and rs9923231 (A) were found to be 11.0%, 11.8%, 11.7% and 12.0%, respectively. The variant allele VKORC1 rs7294 was (80.1%) more frequent and the variant allele CYP4F2 * 3 was found to be 41.8% in South Indians. The allele, genotype and haplotype frequencies of VKORC1 and CYP4F2 gene were distinct from other compared HapMap populations (P < 0.0001).

CONCLUSION:

The findings of our study provide the basic genetic information for further pharmacogenetic based investigation of OA therapy in the population.

Efficacy of cheiloscopy in determination of sex among South indians

INTRODUCTION

Human identification plays a vital role in any crime investigation. Along with the various other established methods, cheiloscopy also plays a key role in linking the criminal with the crime. The ability of a technique in differentiating the sex of a person in the field can help in screening a large number of suspects. This study evaluated the efficacy of cheiloscopy in determination of sex among South Indians. It also studied the pattern of dimorphism in the lips and lip prints of south Indians.

MATERIAL AND METHODS

Lip prints from 100 medical students (50 males and 50 females) were obtained and were analyzed, based on Tsuchihashi and Suzuki classification, to check for dimorphism. Lip dimensions were studied by using standard sliding calipers for dimorphism.

RESULTS AND DISCUSSION

The most common pattern of lip print among males was Type III as compared to Type I in females. The outer four portions of the lip showed statistically significant differences in males and females. Middle portion of the lip was statistically insignificant in sex determination, based on lip print patterns. Thickness of the lip was significantly larger in males as compared to that in females and this criterion could be used to establish a logistic regression for determination of sex of a person.

CONCLUSION

Lips not only significantly differ among the males and females in the pattern of the lip print that they present, but they also differ in their size. These features can effectively be used to determine the sex of a person accurately.

Genetic association of ADIPOQ gene variants with type 2 diabetes, obesity and serum adiponectin levels in south Indian population

OBJECTIVE

To investigate the genetic association of eight variants of the adiponectin gene with type 2 diabetes mellitus (T2DM), obesity and serum adiponectin level in the south Indian population.

METHODS

The study comprised of 1100 normal glucose tolerant (NGT) and 1100 type 2 diabetic, unrelated subjects randomly selected from the Chennai Urban Rural Epidemiology Study (CURES), in southern India. Fasting serum adiponectin levels were measured by radioimmunoassay. The variants were screened by polymerase chain reaction-restriction fragment length polymorphism. Linkage disequilibrium was estimated from the estimates of haplotype frequencies.

RESULTS

Of the 8 variants, four SNPs namely, +276 G/T (rs1501299), -4522 C/T (rs822393), -11365 C/G (rs266729), and +712 G/A (rs3774261) were significantly associated with T2DM in our study population. The -3971 A/G (rs822396) and -11391 G/A (rs17300539) SNPs' association with T2DM diabetes was mediated through obesity (where the association with type 2 diabetes was lost after adjusting for BMI). There was an independent association of +276 G/T (rs1501299) and -3971 A/G (rs822396) SNPs with generalized obesity and +349 A/G (rs2241767) with central obesity. Four SNPs, -3971 A/G (rs822396), +276 G/T (rs1501299), -4522 C/T (rs822393) and Y111H T/C (rs17366743) were significantly associated with hypoadiponectinemia. The haplotypes GCCATGAAT and AGCGTGGGT conferred lower risk of T2DM in this south Indian population.

CONCLUSION

The adiponectin gene variants and haplotype contribute to the genetic risk towards the development of type 2 diabetes, obesity and hypoadiponectinemia in the south Indian population.