Research On The Polymorphism Of The Human Intestinal Fatty Acid Binding Protein Gene And Type 2 Diabetic Nephropathy

Objective: The human intestinal fatty acid binding protein (FABP2) isexcreted only from the absorptive simple columnar epithelial cells of the small intestine and ittransports long-chain fatty acids from the plasma membrane to the endoplasmic reticulum. TheFABP2 gene which G for A substitution in codon 54 of exon 2 can alter the ability ofbinding fatty acid. This polymorphism is close correlated with insulin resistance, type2 DM and its complications. The aim of this study is to investigate the prevalence ofthe polymorphism and explore the relation of FABP2 gene variation with type 2diabetic nephropathy.Methods: After an overnight fast, all subjects'venous blood was drawn forDNA extraction and for measuring some biochemistry parameters. Using PCR-RFLPdetecting the 54 A/T polymorphism in exon2 of FABP2 gene. And then, this genewas cloned so as to sequence the polymorphism of the FABP2 gene. We useindependently colorimetric method and ELASA method to determine the fasting FFAand adiponectin.Results:(1) G for A substitution in FABP2 codon 54 of exon 2 results in thesubstitution of threonine(Thr) for alanine(Ala).(2)The frequence of genotype Ala/Thr&Thr/Thr and Thr allel significantly increased in type 2 DM as compared with that innormally control(P＜0.05). (3)The patients with type 2 DM who carry Ala/Thr andThr/Thr genotype had a significantly higher level of fasting plasma TG(P＜0.05) andfasting FFA(P＜0.05) than those with wild-type. (4) The patients with type 2 DM whocarry Ala/Thr and Thr/Thr genotype had a significantly higher level of insulinresistance index than those with wild-type. (5)The frequence of genotype Ala/Thr andThr/Thr significantly increased in diabetic nephropathy as compared with that innormally control and type 2 DM without nephropathy(P＜0.05) (6) FABP2 Thr54 genotype is independent risk factor, (P＜0.05). (7) The serum adiponectin levels aremarkedly increased in diabetic nephropathy than diabetes without nephropathy ; Thepatients with type 2 DM who carry Ala/Thr and Thr/Thr genotype had a significantlylower level of serum adiponectin (P＜0.05) than those with wild-type.Conclusion: (1)FABP2 gene polymorphism is exist in Tianjin Hangpopulation, and the codon-54 of mutant genotypic frequencies are in Hardy-Weinbergequilibrium. (2) FABP2 gene polymorphism is associated with type 2 DM. (3)FABP2polymorphism may have a certain contribution to dyslipidemia. (4)FABP2polymorphism may be associated with insulin resistance. (5)FABP2 genepolymorphism is associated with diabetic nephropathy, Individuals with FABP254Ala/Thr and Thr/Thr has a higher risk of diabetic nephropathy.