The A54T polymorphism at the intestinal fatty acid binding protein 2 is associated with insulin resistance in glucose tolerant Caucasians.
BACKGROUND
An A54T polymorphism at the fatty acid binding protein 2 (FABP2) locus was found to be associated with insulin resistance in non-diabetic Pima Indians. To see whether this association is present in other populations, we performed a cross sectional study to examine the role of this polymorphism on insulin resistance in 55 healthy and normotensive Caucasian subjects with normal glucose tolerance. Insulin sensitivity (%S) and beta cell function (%B) were assessed using the Homeostasis Model Assessment (HOMA). Their genotypes were determined using a polymerase chain reaction-restriction fragment length polymorphism assay. The relationship between the genotypes and the phenotypes was examined.


RESULTS
After genotyping, we identified 24 AA, 27 AT and 4 TT subjects. The TT subjects were combined with the AT subjects during the analysis due to its small sample size. No differences were noted in gender distribution, clinical features, and fasting lipid profile between the two genotypic groups (AA vs. AT/TT). The AT/TT group had a higher fasting plasma insulin concentration and a lower %S than the AA group (p = 0.0444 and p = 0.0461, respectively). However, no differences were noted in plasma glucose concentrations and %B. Univariate analysis revealed that this polymorphism explained 7.3% of the variation in %S. Multivariate analysis revealed that the polymorphism was an independent determinant for %S (p = 0.0434) and with body mass index accounted for 28.7% of the variation in %S. In contrast, this polymorphism had no impact on %B.


CONCLUSIONS
The A54T polymorphism at the FABP2 locus is a risk factor for insulin resistance in a Caucasian population.
Chiu
K C
KC
Division of Endocrinology, Diabetes and Hypertension, Department of Medicine, University of California, Los Angeles, School of Medicine, Los Angeles, California, USA. kchiu@mednet.ucla.edu
Chuang
L M
LM
Yoon
C
C
D002352:Carrier Proteins / Q000235:genetics*; D003430:Cross-Sectional Studies; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D020022:Genetic Predisposition to Disease; D005838:Genotype; D005951:Glucose Tolerance Test; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D009363:Neoplasm Proteins; D010641:Phenotype; D020641:Polymorphism, Single Nucleotide; D025521:Tumor Suppressor Proteins; D044465:White People / Q000235:genetics*
D002352:Carrier Proteins; C493404:FABP2 protein, human; C107608:FABP7 protein, human; C493405:Fabp2 protein, mouse; D000071438:Fatty Acid-Binding Protein 7; D050556:Fatty Acid-Binding Proteins; D009363:Neoplasm Proteins; D025521:Tumor Suppressor Proteins