Associations of adiponectin with individual European ancestry in African Americans: the Jackson Heart Study

作者：Bidulescu Aurelian^*; Choudhry Shweta; Musani Solomon K; Buxbaum Sarah G; Liu Jiankang; Rotimi Charles N; Wilson James G; Taylor Herman A; Gibbons Gary H

来源：Frontiers in Genetics, 2014, 5: 22.

DOI：10.3389/fgene.2014.00022

• cohort study
• adiponectin
• individual European ancestry
• minorities
• African Americans
• obesity
• insulin resistance

Background: Compared with European Americans, African Americans (AAs) exhibit lower levels of the cardio-metabolically protective adiponectin even after accounting for adiposity measures. Because few studies have examined in AA the association between adiponectin and genetic admixture, a dense panel of ancestry informative markers (AlMs) was used to estimate the individual proportions of European ancestry (PEA) for the AAs enrolled in a large community-based cohort, the Jackson Heart Study (JHS). We tested the hypothesis that plasma adiponectin and PEA are directly associated and assessed the interaction with a series of cardio-metabolic risk factors.
Methods: Plasma specimens from 1439 JHS participants were analyzed by ELISA for adiponectin levels. Using pseudo-ancestral population genotype data from the HapMap Consortium, PEA was estimated with a panel of up to 1447 genome-wide preselected AlMs by a maximum likelihood approach. Interaction assessment, stepwise linear and cubic multivariable-adjusted regression models were used to analyze the cross-sectional association between adiponectin and PEA.
Results: Among the study participants (62% women; mean age 48 +/- 12 years), the median (interguartile range) of PEA was 15.8 (9.3)%. Body mass index (BMI) (p = 0.04) and insulin resistance (p = 0.0001) modified the association between adiponectin and PEA. Adiponectin was directly and linearly associated with PEA (beta = 0.62 +/- 0.28, p = 0.03) among non-obese (n = 673) and insulin sensitive participants (n = 1141; beta = 0.74 +/- 0.23, p = 0.001), but not among those obese or with insulin resistance. No threshold point effect was detected for non-obese participants.
Conclusions: In a large AA population, the individual proportion of European ancestry was linearly and directly associated with plasma adiponectin among non-obese and non insulin-resistant participants, pointing to the interaction of genetic and metabolic factors influencing adiponectin levels.

• 出版日期2014-2-10