Association Study of Candidate Gene Polymorphisms and Obesity in a Young Mexican-American Population from South Texas

Abstract

Background and Aims Obesity is increasingly a health problem and a risk factor for diabetes in young Mexican-American populations. Genetic association studies in older, mostly non-Hispanic populations have reported that polymorphisms in the candidate genes HSD11B1, CRP, ADIPOQ, PPARG, ANKK1, ABCC8 and SERPINF1 are associated with obesity or diabetes. We analyzed the polymorphisms rs846910, rs1205, rs1501299, rs1801282, rs1800497, rs757110 and rs1136287in these candidate genes, for association with obesity and metabolic traits in a young Mexican-American population from south Texas. Methods Genotyping of the seven common SNPs were performed by allelic discrimination assays in 448 unrelated Mexican Americans (median age = 16 years) from south Texas. χ2 tests and regression analyses using additive models were used for genetic association analyses adjusting for covariates; p values were corrected for multiple testing by permutation analyses. Results rs1800497 (ANKK1) shows association with waist circumference (p = 0.009) and retains the association (p = 0.03) after permutation testing. Analysis of metabolic quantitative traits shows that rs846910 (HSD11B1) was associated with HOMA-IR (p = 0.04) and triglycerides (p = 0.03), and rs1205 (CRP) with HOMA-IR (p = 0.03) and fasting glucose levels (p = 0.007). However, the quantitative traits associations are not maintained after permutation analysis. None of the other SNPs in this study showed associations with obesity or metabolic traits in this young Mexican-American population. Conclusions We report a potential association between rs1800497 (linked to changes in brain dopamine receptor levels) and central obesity in a young Mexican-American population.

Lack of association of the HSD11B1 gene polymorphisms with obesity and other traits of metabolic syndrome in children and adolescents

“…Although data from adults do not confirm direct effect of HSD11B1 polymorphisms on body mass, an association with obesity and its measures (BMI, WC, waist-to-hip ratio) was reported in Spanish, American and Chinese children [20,21,23]. Results with regard to insulin and its action are contradictory in Spanish and Mexican-American youth [20,22]. This latter cohort also revealed a relationship between HSD11B1 polymorphism and circulating triglycerides [22].…”

“…In a small American study an association between an adenine insertion in HSD11B1 gene intron 3 (ins4436A, rs45487298) and increased BMI, waist-to-hip ratio and insulin resistance indices in children was found [21]. More recent analysis in young Mexican-Americans confirmed that rs846910 was associated with Homeostatic Model Assessment of Insulin Resistance (HOMA-IR) and circulating triglycerides but not with obesity [22]. Finally, a Chinese study linked several HSD11B1 variants with childhood obesity and its cardiometabolic complications -hypertension, hypercholestarolaemia, and hyperglycaemia [23].…”

“…Results with regard to insulin and its action are contradictory in Spanish and Mexican-American youth [20,22]. This latter cohort also revealed a relationship between HSD11B1 polymorphism and circulating triglycerides [22].…”

AVALIAÇÃO DOS NÍVEIS DE PROTEÍNA C REATIVA CIRCULANTE E DO SNP rs1205 DO GENE CRP COM OBESIDADE, CARACTERÍSTICAS ANTROPOMÉTRICAS E MARCADORES BIOQUÍMICOS

“…A Proteína C Reativa (PCR) é um marcador inflamatório importante e os níveis circulantes desta proteína podem ter um valor prognóstico na identificação de indivíduos com maior risco de desenvolver obesidade, diabetes mellitus tipo 2 e resistência à insulina, sendo que o gene da Proteína C Reativa (CRP) está associado com glicose em jejum alterada e resistência à insulina (DURAN-GONZALEZ et al, 2011 …”

Basic and Genetic Aspects of Food Intake Control and Obesity: Role of Dopamin Receptor D2 TaqIA Polymorphism

“…58 In the Netherlands, the A1 allele frequency was 18.3% in obese children 59 and in NorthAmerican studies with obese children, it ranged from 17.0% 60 to 38.5%. 61 In a Brazilian study with obese and normal weight (controls) children, the A1 allele frequencies were 34.5% and 23.0%, respectively, and a statistically significant association between the A1 allele and obesity was verified.…”