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Background: To determine the association of the A55T and K153R polymorphisms of the Myostatin gene with obesity, abdominal obesity and lean body mass (LBM) in Asian Indians in north India. Materials and Methods: A total of 335 subjects (238 men and 97 women) were assessed for anthropometry, % body fat (BF), LBM and biochemical parameters. Associations of Myostatin gene polymorphisms were evaluated with anthropometric, body composition and biochemical parameters. In A55T polymorphism, BMI (p = 0.04), suprailiac skinfold (p = 0.05), total skinfold (p = 0.008), %BF (p = 0.002) and total fat mass (p = 0.003) were highest and % LBM (p = 0.03) and total LBM (Kg) were lowest (p = 0.04) in subjects with Thr/Thr genotype as compared to other genotypes. Association analysis of K153R polymorphism showed that subjects with R/R genotype had significantly higher BMI (p = 0.05), waist circumference (p = 0.04), %BF (p = 0.04) and total fat mass (p = 0.03), and lower %LBM (p = 0.02) and total LBM [(Kg), (p = 0.04)] as compared to other genotypes. Using a multivariate logistic regression model after adjusting for age and sex, subjects with Thr/Thr genotype of A55T showed high risk for high %BF (OR, 3.92, 95% Cl: 2.61-12.41), truncal subcutaneous adiposity (OR, 2.9, 95% Cl: 1.57-6.60)] and low LBM (OR, 0.64, 95% CI: 0.33-0.89) whereas R/R genotype of K153R showed high risk of obesity (BMI; OR, 3.2, 95% CI: 1.2-12.9; %BF, OR, 3.6, 95% CI: 1.04- 12.4), abdominal obesity (OR, 2.12, 95% CI: 2.71-14.23) and low LBM (OR, 0.61, 95% CI: 0.29-0.79). Conclusions/Significance:We report that variants of Myostatin gene predispose to obesity, abdominal obesity and low lean body mass in Asian Indians in north India. [ABSTRACT FROM AUTHOR]

Objectives: Obesity is associated with high levels proinflammatory cytokines like tumour necrosis factor alpha (TNF-α), which may play an important role in the genesis of insulin resistance. We evaluated the relationship of -308G/A polymorphism of TNF-α gene with obesity and insulin resistance in Asian Indians in north India. Methods: This cross-sectional study included 151 apparently healthy individuals (79 males, 72 females) 18-50 yrs of age from New Delhi, India. Body composition by dual-energy x-ray absorptiometry (DEXA) and abdominal fat by magnetic resonance imaging (MRI) were measured. Biochemical measurements included OGTT, lipids, fasting insulin, hs-CRP and TNF-α levels. We analysed -308G/A polymorphism of TNF-α gene and studied its association with obesity and biochemical parameters. Results: At comparable BMI, abdominal obesity was more prevalent in females (50%) as compared to males (20%). The wild genotype (GG) was present in 78.8%, GA in 17.9%, and AA in 3.3% subjects. Measures of body composition, abdominal fat distribution, lipids, insulin, hs-CRP and TNF-α levels were not influenced by the presence of -308G/A polymorphism. Serum TNF-α levels correlated significantly with fasting insulin in both genders. Conclusion: TNF-α levels correlate with fasting insulin but not with indicators of body composition in Asian Indians. The -308G/A polymorphism of TNF-α gene is not associated with differences in the serum levels of TNF-α in Asian Indians. [ABSTRACT FROM AUTHOR]

Background: Obstructive sleep apnea (OSA) is prevalent in 7.5% in urban Asian Indians. Peroxisome proliferator activated receptor gamma2 (PPARγ2) has been implicated in adipocyte differentiation. Neuropeptide Y (NPY) is also considered as a candidate gene for excess body fat accumulation. The association of PPARγ2 (Pro12Ala)} and NPY (Leu7Pro) gene polymorphisms with OSA has not been studied in Asian Indians. Objective: To study the distribution of PPARγ2 (Pro12Ala) and NPY (Leu7Pro) polymorphism in Asian Indians with and without OSA. Methods and results: This study was carried out in 252 obese subjects [(body mass index (BMI > 25 kg/m^{2})]; 142 with OSA and 110 without OSA. Measurements included anthropometric and biochemical parameters (fasting blood glucose, lipid profile, various circumferences and skin-fold thicknesses). PPARγ2 (Pro12Ala) and NPY (Leu7Pro) gene} polymorphisms were studied in all subjects. The frequency of the variant allele (Ala12) of PPARγ2 gene was significantly higher in subjects with OSA (14.4%) when compared with subjects without OSA (5.5%; χ^{2}= 9.7; p = 0.001). The distribution of the variant allele (Pro7) of NPY gene was comparable in subjects with OSA (3.5%) and without OSA (3.6%; χ ^{2} = 0.001, p = 0.94). Conclusion: This study reveals a significantly higher frequency of PPARγ2 (Ala12) allele in obese Asian Indians with OSA when compared to obese Asian Indians without OSA. [ABSTRACT FROM AUTHOR]

Background: Several studies hinted about the clustering of risk variables of the metabolic syndrome (MS) and suggested that the underlying genetic polymorphisms could be responsible for the increasing incidence of coronary heart disease (CHD) in people of Indian origin. Therefore, identification of the components of the MS along with the genetic factors could be one of the aspects to make an attempt to prevent the increasing incidence of CHD. Materials and Methods: Principal component factor analysis (PCFA) was undertaken to identify the components or factors of the MS among the adult (⩾30 years) Asian Indians living in and around Calcutta, India. The study comprised 350 adult Asian Indians. Anthropometric measurements were taken, and lipid profiles, blood pressure and fasting blood glucose were measured for each participant. Two genetic polymorphisms, namely, angiotensin converting enzyme (ACE) gene polymorphism (insertion/deletion [I/D]) or ACE (I/D) and apolipoproteinE (Hha I) were also studied. Results: PCFA revealed 3 factors that cumulatively explained 65.39% of the observed variance of the MS by measured variables. The 3 factors identified were lipids and lipoprotein (Factor 1), centripetal fat and blood pressure (Factor 2), and ACE (I/D) polymorphism with blood pressure (Factor 3). Moreover, the first 2 factors, that is, lipids, lipoprotein, centripetal fat, and blood pressures cumulatively explained ∼46% (45.94%) of the observed variance of MS in this population. Conclusions: Since more than 1 factor was identified for the MS phenotype, more than 1 physiogenetic mechanism could be accounted for MS in the Asian Indian population. [ABSTRACT FROM AUTHOR]

Adiponectin is an adipose tissue specific protein that is decreased in subjects with obesity and type 2 diabetes. The objective of the present study was to examine whether variants in the regulatory regions of the adiponectin gene contribute to type 2 diabetes in Asian Indians. The study comprised of 2,000 normal glucose tolerant (NGT) and 2,000 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. We identified two proximal promoter SNPs (−11377C→G and −11282T→C), one intronic SNP (+10211T→G) and one exonic SNP (+45T→G) by SSCP and direct sequencing in a pilot study ( n = 500). The +10211T→G SNP alone was genotyped using PCR-RFLP in 4,000 study subjects. Logistic regression analysis revealed that subjects with TG genotype of +10211T→G had significantly higher risk for diabetes compared to TT genotype [Odds ratio 1.28; 95% Confidence Interval (CI) 1.07–1.54; P = 0.008]. However, no association with diabetes was observed with GG genotype ( P = 0.22). Stratification of the study subjects based on BMI showed that the odds ratio for obesity for the TG genotype was 1.53 (95%CI 1.3–1.8; P < 10−7) and that for GG genotype, 2.10 (95% CI 1.3–3.3; P = 0.002). Among NGT subjects, the mean serum adiponectin levels were significantly lower among the GG ( P = 0.007) and TG ( P = 0.001) genotypes compared to TT genotype. Among Asian Indians there is an association of +10211T→G polymorphism in the first intron of the adiponectin gene with type 2 diabetes, obesity and hypoadiponectinemia. [ABSTRACT FROM AUTHOR]

The high incidence of obesity has resulted in increased morbidity and mortality worldwide. Obesity, a common lifestyle disorder, is caused by multiple factors with heredity playing a strong causal role. Recently, a genetic variation upstream of insulin-induced gene 2 ( INSIG2) (rs7566605) has been reported to be associated with obesity in four separate cohorts. Because the lifestyle and food preferences of a large proportion of Indian population differ from the rest of the world, we studied the impact of this polymorphism with body mass index (BMI). The study consisted of two cohorts – 1577 healthy individuals from three major linguistic lineages in India and 610 coronary artery disease cases and controls. In the two cohorts studied, no significant association was observed between the polymorphism and BMI. However, frequency of homozygous variant genotype was higher in non-obese individuals as compared with obese individuals in both cohorts although the difference was marginally significant only in the case–control cohort under the assumption of a recessive model. Furthermore, regardless of age and sex, mean BMI did not vary with genotype under the assumptions of recessive model. Thus, in contrast to earlier reports, the variant upstream of INSIG2 is not a determinant of BMI in Indian population. [ABSTRACT FROM AUTHOR]

We and others in a variety of ethnic groups have previously described associations of various SNPs of the uncoupling protein genes UCP2 and UCP3 (located within 17 kb of each other on chromosome 11q13) with both central fat disposition and BMI. The aim of this study was to do a replication study in South Indian subjects using a family based approach and selecting SNP's by' a priori hypothesis' defined by a previous association with obesity/waits in other studies and/or functional data. Five SNPs were studied; 1 by Ampliflour (UCP2-866 rs659366), 1 by SNAPSHOT (UCP3Y210Y rs2075577), 2 by TaqMan (UCP3-55 rs1800849, UCP2 A55V rs660339) and one by PCR-RFLP (UCP2 exon 8 INDEL) in 882 South Indian participants from 236 families ascertained from community based study of healthy families living in Chennai, India. Statistical analysis was performed using SOLAR and anthropometric variables were corrected for age and sex. The QTLD analysis showed the BMI was associated to the UCP3 rs1800849 (AA 23.9±0.29, AB 23.5±0.32, BB 23.0±0.5, p=0.027) and UCP3 rs2075577 (AA 24.6±0.37, AB 24.0±0.30, BB 23.4±0.39, p=0.022). Waist circumference to the UCP2 rs660339 (AA 84.3±0A8, AB 85.1±0.41, BB 85.9±0.65, p=0.028). Body fat percentage to UCP2 rs660339 (AA 22.9±0.31, AB 23.2±0.27, BB 23.5±0.42, p=0.048) and UCP2 rs659366 (AA 22.7±0.31, AB 22.9±0.26, BB 23.27±0.41, p=0.076). This detailed analysis confirms associations between anthropometric traits and the UCP2/UCP3 locus but that separate SNPs are associated with either BMI or fat distribution. [ABSTRACT FROM AUTHOR]