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Background: The polycystic ovary syndrome (PCOS) is a hyperandrogenic disorder that arise from a combination of genetic and environmental factors., Aim: To assess the role of the androgen receptor (AR) CAG repeat polymorphism in the metabolic and reproductive features in daughters of women with PCOS (PCOSd)., Methods: Sixty-seven PCOSd and 60 daughters of control women (Cd) were studied in early stages of sexual development. Sex steroids, glucose, insulin and lipids were determined. The AR CAG repeat sizes and X-chromosome inactivation (XCI) were analyzed., Results: PCOSd and Cd had similar mean number of CAG repeats and XCI pattern. In PCOSd and Cd, methylation-weighted biallelic means CAGn (mwCAGn) was not associated with androgen levels. In infants and pubertal PCOSd, mwCAGn was associated with a low concentration of HDL-cholesterol., Conclusions: AR CAG repeat polymorphism appears to be unrelated with serum androgen levels. However, the short mwCAGn variant may have a possible impact on the lipid profile in PCOSd.

Introduction: Interleukin-6 receptor (IL6R) has been linked with type 2 diabetes and obesity. The presence of the Asp allele in Asp358Ala of IL6R has been linked with insulin resistance and weight gain., Aim: The aim of this study is to evaluate the frequency and the association of the Asp358Ala in the IL6R gene in Chilean women with type 1 diabetes (T1D) and its relationship with body mass index (BMI)., Patients and Methods: One hundred and forty-five patients with T1D (N = 145) and healthy control women (N = 103) were recruited. The polymorphisms were studied with polymerase chain reaction and restriction fragment length polymorphisms. The effect of the polymorphisms on BMI and age of diagnosis was evaluated., Results: A higher frequency of the Asp allele was observed in patients with T1D compared with controls (0.483 vs. 0.364; p < 0.01). The Asp358Asp genotype was more prevalent in the T1D group compared with controls (0.152 vs. 0.097; p < 0.01). T1D patients younger than 19 years had a positive association of BMI-standard deviation scores with the Asp allele (p < 0.05). Finally, lower Glycated Hemoglobin 1c (HbA1c) levels were observed in patients carrying the Asp allele (p < 0.01)., Conclusions: T1D in Chilean women appears to be associated with the presence of the Asp allele in IL6R. The IL6R polymorphism (Asp358/Asp) was associated with BMI in T1D patients. This genetic variant could have some role in weight gain in T1D women.

Background: A polymorphism located in the promoter region (-174 G/C) of interleukin 6 (IL-6) has been linked to early onset of type 1 diabetes (T1D) and increased body mass index (BMI)., Aim: To evaluate the possible association of this -IL-6 gene 174 GIC polymorphism with T1D, BMI and metabolic control in T1D patients in a case-control study., Patients and Methods: -174 G I C polymorphisms were analyzed by polymerase chain reaction and restriction fragment length polymorphism in 145 women with T1D and 103 healthy controls. BMI and BMI-Z-scores were tabulated and metabolic control was recorded., Results: There was a higher frequency for the C allele in T1D patients compared with the control group (21% versus 14.1%, p = 0.047). No significant differences in genotype frequencies for the -174 GIC polymorphism of IL-6 gene between patients with T1D and controls, were observed. There were no significant associations with T1D and BMI., Conclusions: A higher frequency of C allele in women with T1D was the only finding in this series, suggesting that the polymorphic variant is not related to weight gain in these patients.

CTLA-4 plays a key role in T cells regulation. We analysed the CTLA-4 +49A/G and -318C/T polymorphisms in 178 cases of type 1 diabetes and their parents (534 individuals) from Santiago, Chile. A significant overall association with T1D (p=0.028) was observed, possibly due to an overtransmission of the G-T haplotype.

Aim: To explore the contribution of the PD-1 gene polymorphisms involved in T1D as well as the relationship between the PD-1/CTLA-4 genes and soluble CTLA-4 concentrations., Patients and Methods: 261 incident cases of T1D and 280 healthy children less 15 years old were included in this study. Haplotypes for polymorphisms of the PD-1 and CTLA-4 genes were determined by PCR and RFLP methods. Screening for soluble CTLA-4 was done using an ELISA assay. Statistical analysis was performed using the online SHESIS package., Results: Our results show that sCTLA-4 levels were higher in T1D than in controls (2.99+/-1.7 ng/ml versus 1.43+/-0.31 ng/ml, p<0.001). The allele dosage of CTLA-4 on PD-1 haplotypes, showing a significant modified effect of G carriers over AA genotype on the sCTLA-4 concentrations (5.48+/-2.09 ng/ml versus 3.27+/-1.30 ng/ml, p<0.03 in T-C haplotype) and (1.92+/-0.79 ng/ml versus 3.41+/-1.10 ng/ml, p<0.02 in C-T haplotype)., Conclusion: Consistent with the higher serum sCTLA-4 levels observed in other autoimmune diseases, our results suggest that sCTLA-4 is elevated in T1D. Our data suggest a possible gene dosage effect of "G"CTLA-4 carriers on sCTLA-4 over the possible protective or susceptible effect conferred by PD-1 haplotypes.

CTLA-4 is a homeostatic regulator of T cell activation and is believed to play a critical role in immune tolerance. Polymorphisms in the CTLA-4 promoter (-318C/T) and in exon 1 (+49 A/G) were analyzed in 300 Chilean patients with type 1 diabetes mellitus (T1D) and 310 healthy children by polymerase chain reaction-restriction fragment length polymorphism. The effect of CTLA-4 allele and haplotype frequencies on the interferon-gamma, tumor necrosis factor-alpha, and transforming growth factor-beta(1) levels and the presence in serum of GAD65 and IA-2 autoantibodies at the onset of T1D was evaluated. The distribution of the CTLA-4 allele and genotype frequencies was found to be similar in patients and control children. However, among the T1D patients' carriers of GG genotype on CTLA-4 gene a higher frequency of anti-GAD65 autoantibodies (87.2%) was observed. On the other hand, higher ketoacidosis at onset, younger age at onset, and higher levels of tumor necrosis factor-alpha and interferon-gamma were observed in T1D patients carriers of G allele in comparison with the carriers of AA genotype. In conclusion, the result of this study showed that CTLA-4 +49 A/G and -318 C/T polymorphisms were not linked with a higher genetic risk for T1D. However, the presence of a GG genotype or G allele dosage was associated with a younger age of onset, higher prevalence of ketoacidosis at the moment of diagnosis and positive anti-GAD65 serum autoantibodies.

The aim of this study was to establish the frequency of gene CYP17 promoter polymorphism in women with polycystic ovary syndrome (PCOS) from a Chilean population and to examine the association of this polymorphism with body weight and estimate of insulin resistance in PCOS patient carriers and noncarriers of the A2 allelic variant. A total of 159 women with clinical and hormonal evidence of PCOS and 93 healthy women (HW) were evaluated. Diagnosis of PCOS was made according to the National Institutes of Health consensus criteria. In PCOS and HW, an oral glucose tolerance test was performed; and serum glucose and insulin were measured before the glucose load and 30, 60, 90, and 120 minutes after. Lipid profile and free fatty acid concentrations were determined in the basal sample. Insulin resistance was evaluated by homeostatic model assessment and insulin sensitivity index composite. A polymerase chain reaction-restriction fragment length polymorphism analysis was performed in all women to determine the A2 allele of the gene CYP17 promoter. The genotype frequency was similar between HW and PCOS women. No differences in anthropometric measurements and metabolic parameters were observed in HW carrier and noncarrier of the A2 variant. In PCOS women, an increase in body mass index, waist circumference, homeostatic model assessment of insulin resistance, and fasting insulin according to the A2 allele dosage was observed (P = .008, P = .016, P = .012, and P = .006, respectively). Polycystic ovary syndrome patient carriers of the A2 allele with a body mass index greater than 29.9 kg/m(2) showed an odds ratio of 9.1 (confidence interval, 3.0-27.4; P < .0001) for developing insulin resistance. These data suggest that the frequency of the A2 allele is similar between PCOS patients and HW; however, the presence of this gene defect in PCOS patients seems to be associated with increase in body weight, abdominal adiposity, and metabolic components.

Background and Objective: In order to assess whether Fok I vitamin D receptor gene (VDR) polymorphism is involved in the genetic susceptibility of type 1 diabetes, a case-control study was conducted and VDR genotypes were related to serum concentrations of 25(OH) vitamin D and cytokines transforming growth factor beta1 (TGF-beta1) and interferon gamma (INF-gamma)., Patients and Method: 151 incident cases of type 1 diabetes and 182 non related healthy controls from Santiago were studied for VDR polymorphisms in peripheral blood DNA. Exon 2 (Fok I) segments were amplified by polimerase chain reaction and analyzed by means of restriction fragment length polymorphism to determine each corresponding genotype. Differences for allele, genotype and serological markers as 25(OH) vitamin D, TGF-beta1 and INF-gamma levels distribution between patients and controls were analyzed., Results: Fok I polymorphism distribution analysis showed no differences between patients and controls. Among diabetics, higher levels of TGF-beta1 (median, 282.6 pg/ml; range, 131.8-3,031.4) were observed compared with healthy children (median, 232.2 pg/ml; range, 135.7-506.5) (p < 0.0038). Similar results were observed for INF-gamma concentrations (median, 121.1 pg/ml, and range, 5.3-228.8, in cases, and median, 89.6 pg/ml, and range, 10.9-117.2 in controls) (p < 0.0004). The diabetic carriers of the ff genotype showed low levels of 25(OH) vitamin D compared with the carriers of the F allele: mean (standard deviation), 23.1 (5.9) versus 27.9 (10.3) ng/ml (p < 0.03). A similar result was observed for TGF-beta1 concentrations in diabetic carriers of ff genotype and patients carriers of the F allele (298.5 versus 276.6; p < 0.05)., Conclusions: Fok I polymorphism of VDR could have a marginal role in the immunologic disturbance in type 1 diabetes.

Objective: To evaluate the influence of ApaI, BsmI and TaqI polymorphisms of the VDR gene and HLA-DQB1* alleles in type 1 diabetic children and to assess their possible relationship with circulating levels of 25-hydroxyvitamin D(3), auto-antibodies, and INFgamma/TGFbeta1 cytokines levels in Chilean cases and controls., Methods: DNA and serum samples from 216 newly diagnosed type 1 diabetic and 203 unrelated control children were evaluated for IA-2 and GAD(65) auto-antibodies, 25-hydroxyvitamin D(3) levels, HLA-DQB1* alleles, and VDR gene polymorphisms., Results: The frequency of the b allele and the bb genotype in type 1 diabetic patients was significantly lower compared with the control group (0.635 versus 0.749, p<0.01 and 0.370 versus 0.567, p<0.04). 25-Hydroxyvitamin D(3) levels showed no differences between type 1 diabetic and healthy children. In cases, 25-hydroxyvitamin D(3) levels were not associated with a special auto-antibodies profile according to the presence or absence of GAD(65)(+) or IA-2(+). The haplotype combination BAT was higher in cases (0.062 versus 0.019, p<0.0022) and bAT was more frequent in controls (0.266 versus 0.180, p<0.003). In cases, the aaBbTT genotype showed the most significant increase in TGFbeta1 level across the VDR categories. Finally, when considering the HLA class II risk genotype (DQB1*0302) and the VDR genotypes (AabbTT and aabbTT), higher levels of GAD(65), IA-2 and TGFbeta1 were observed among diabetic children., Conclusion: We found an association between a VDR polymorphism (BsmI) and type 1 diabetes. An association was found of AabbTT and aabbTT genotypes and the HLA-DQB1*0302 allele with high levels of GAD(65), IA-2 and TGFbeta1.

The aim of this study was to assess the frequency of fatty acid binding protein 2 (FABP2) Ala54Thr genetic polymorphism and to evaluate its association with obesity and insulin resistance in Chilean aboriginal populations. A sample of 96 urban Aymara and 111 urban Mapuche subjects aged 20-80 years were recruited for this cross-sectional study. Glucose, insulin and lipid profile were measured in fasting plasma samples. Insulin resistance was estimated through the HOMA-IR model. FABP2 Ala54Thr genotypes were determined by PCR followed by RFLP analysis. The allele frequency of Thr54 variant was estimated as 18.2% in Aymara subjects, which is one of the lowest reported to date. The corresponding frequency in Mapuche subjects was 31.9% (p<0.002). Regarding genotype-phenotype associations, no significant differences were found in any of the anthropometric or metabolic variables according to Ala54Thr genotypes. After adjustment by BMI and metabolic variables through a logistic regression analysis, the association of the FABP2 polymorphism with ethnic group persisted (Mapuche group: OR=2.37, 95% CI 1.319-4.277, p=0.004) It is unlikely that Ala54Thr polymorphism of the FABP2 gene plays a relevant role in obesity and insulin resistance in Chilean ethnic groups.

Background: It has been proposed that the toll-like receptor-4 gene (TLR4) may participate in the development of obesity and osteoporosis, in addition to its well-known role in the immune response. On the other hand, the adipose tissue of obese subjects shows an increased expression of the proinflammatory cytokine, tumour necrosis factor-alpha (TNF-alpha), which is released after lipopolysaccharide recognition by TLR4., Aim: To estimate the allele/genotype frequencies and linkage disequilibrium measures of Asp299Gly and Thr399Ile polymorphisms of the TLR4 gene in the Chilean elderly population, and to screen for their association with variables related to adiposity or bone mineral density., Subjects and Methods: The study group included 227 unrelated Chilean elderly women (61-95 years) recruited from a population-based sample. Adiposity and bone mineral density measures were obtained using dual-energy X-ray absorptiometry., Results: The allele frequencies for TNF -308A, TLR4 299Gly and TLR4 -399Ile were 9.3%, 4.6% and 4.4%, respectively, with Asp299Gly and Thr399Ile being in strong linkage disequilibrium (D' = 0.88). Although seriously restricted by the low frequency of the allele variants, no relevant association between genotypes and adiposity-related variables were found. Likewise, no significant association between osteoporosis status (categorized as osteoporosis, osteopenia or normal status) with TLR4 Asp299Gly or TNF -308G>A genotypes was found., Conclusion: It is unlikely that TLR4 Asp299Gly, TLR4 Thr399Ile or TNF -308G>A polymorphisms have a major influence on adiposity, bone mineral density or osteoporosis status in Chilean elderly women.

Objective: To establish the frequency of the Trp64Arg polymorphism of the beta3 adrenergic receptor (ADRB3) in women with polycystic ovary syndrome (PCOS) from a Chilean population, focusing particularly on the interaction with body weight. In addition, we evaluated the relationship of the Trp64Arg variant with other metabolic components of this syndrome., Patients and Design: In a case-control design study, a total of 106 women with clinical and hormonal evidence of PCOS and 82 healthy women (HW) were evaluated., Measurements: An oral glucose tolerance test (OGTT) was performed and serum glucose and insulin were measured before the glucose load and 30, 60, 90 and 120 min after. Lipid profile was determined in the basal sample. Insulin resistance was assessed by the homeostatic model assessment (HOMA(IR)) and insulin sensitivity index (ISI) composite. A polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP) analysis was performed to determine the Trp64Arg polymorphism of ADRB3., Results: The frequency of the heterozygous condition was similar between PCOS and HW (39%vs. 35%). Only two subjects were homozygous for arginine, both belonging to the PCOS group and having a body mass index (BMI) > 30 kg/m2. In the crude analysis, hypothesis tests and odds ratios show that there is no evidence of association between the ADRB3 Trp64Arg variant and PCOS (P = 0.47). Moreover, when data were stratified by BMI categories, the statistical test for interaction between Trp64 carrier status and obesity was not significant (P = 0.29). This variant was present in 52% of the obese PCOS patients and 40% of the obese HW. In normal weight and obese PCOS carriers, the presence of the Trp64Arg variant was associated with high triglyceride (TG) levels. A major effect of the Trp64Arg variant on insulin resistance parameters could not be demonstrated., Conclusions: The frequency of the Trp64Arg polymorphism was similar in healthy women and PCOS women, and a possible interaction between the effect of this variant and obesity in PCOS could not be demonstrated. However, our results showed an association between triglyceride levels and the presence of this genetic variant in PCOS women.

Objective: To assess the association between the Ala54Thr genetic polymorphism of the fatty acid-binding protein 2 (FABP2) gene with insulin resistance and obesity., Research Methods and Procedures: According to a sampling scheme based on BMI, 33 adult obese women (BMI > or = 30) and 30 adult normal-weight women (BMI > 18.5 and < 25 kg/m(2)) were recruited for this study. Women with chronic inflammatory diseases or acute pathology were excluded. Glucose, insulin, leptin, lipids, and tumor necrosis factor alpha (TNF alpha) were measured in fasting plasma samples. Insulin resistance was estimated through the homeostasis model assessment for insulin resistance method. The Ala54Thr allelic variant was determined by polymerase chain reaction, followed by restriction fragment-length polymorphism analysis., Results: The Thr54 allele was more frequent in obese than in nonobese women (47.0% vs. 31.7; p = 0.08). Among obese women, higher TNF alpha concentrations were found when comparing the Thr54/Thr54 genotype (30.0 +/- 7.1 pg/mL) with either the Ala54/Thr54 genotype (21.2 +/- 8.4 pg/mL) or the Ala54/Ala44 genotype (20.1 +/- 7.0 pg/mL) (p < 0.05). In addition, higher fasting plasma insulin and leptin levels were found among Thr54/Thr54 homozygotes compared with the other genotypes (p < 0.05)., Discussion: Our results suggest that the Ala54Thr polymorphism of the FABP2 gene is associated with obesity and insulin resistance. The effect of this polymorphism might be mediated by elevated production of TNF alpha.

Several reports have found a relation between polymorphisms of the vitamin D receptor gene (VDR) and the development of type 1 diabetes. We have examined the association of three VDR polymorphism with type 1 diabetes in 59 Chilean case-parents trios. Genotyping for Bsm1, Apal and Taq1 polymorphism were performed. Transmission/ disequiibrium tests were used to assess gene-disease associations through the evaluation of allelic transmission to affected offspring. Non-significant increased transmissions of B allele (probability of transmission = 52.5%, p = 0.69), A allele (probability of transmission = 58.4%, p = 0.17) and T allele (probability of transmission = 52.0%, p = 0.77) were estimated in Bsml, Apal and Taql sites, respectively. Haplotype-based analyses showed non-significant preferential transmissions (global p = 0.52). The present study does not support the hypothesis of a significant contribution of VDR alleles in the etiology of type 1 diabetes of Chilean cases.

Susceptibility to the type 1 diabetes is genetically controlled and there is an increased risk associated with the presence of some specific alleles of the human leukocyte antigens class II loci (DQA1 and DQB1 genes). The purpose of this study is to evaluate the association between type 1 diabetes and HLA DQ alleles using case-parents trios in the admixed population of Uruguay composed by a mixture of Caucasian, Amerindian and Negroid populations. DQA1 and DQB1 genotyping was performed by polimerase chain reaction followed by oligospecific probes hybridization in 51 case-parents trios. The transmission disequilibrium test was used for detecting differential transmission in the HLA DQ loci. DQB1*0302 was the only allele for which preferential transmission is suggested (probability of transmission = 67.56%; exact p-value TDT = 0.047 uncorrected for multiple comparisons). DQA1*0301 allele showed a trend for preferential transmission without achieving statistical significance. This result would confirm the hypothesis previously advanced in a case-control study. Therefore, DQB1*0302 allele could be considered as the most important susceptibility allele for developing type 1 diabetes in Uruguay population.

The human leukocyte antigen (HLA) system plays a crucial role in the autoimmune process leading to childhood diabetes. The purpose of this study was to evaluate the association between type 1 diabetes and the polymorphism encoded by the HLA-DQB1 gene by using case-parents trios. The study area was the metropolitan region of Santiago, Chile, and cases were ascertained from March 1997 to August 1998. Genotyping was performed in 94 trios comprising incident cases less than 17 years of age at the time of diagnosis and their parents. The transmission/disequilibrium test was used to detect differential transmission in the HLA-DQB1 locus. The authors found that alleles DQB1(*)0302 and DQB1(*)0201 were strongly associated with the disease. By using 1:3 matched sets of cases-pseudosibs and conditional logistic regression models, allelic relative risks were estimated for DQB1(*)0302 (r = 7.2, 95% confidence interval: 2.8, 18.5) and DQB1(*)0201 (r = 4.7, 95% confidence interval: 1.9, 11.6); DQB1(*)0301 was considered the baseline allele. When case-parents trios were used, alleles DQB1(*)0302 and DQB1(*)0201 were strongly associated with a higher risk of type 1 diabetes in the population of SANTIAGO: