Background/aims: Low glycemic index (GI) diets may have beneficial effects on glycemic control and serum lipid levels in patients with type 2 diabetes, but whether its effect is affected by polymorphisms of genes associated with lipid metabolism remains unclear. This study investigated whether the effects of a low-GI diet on serum lipids and glycemic control in patients with diabetes are associated with polymorphisms of FABP2  Ala54Thr (rs1799883).
Methods: A retrospective study was conducted involving 165 patients with type 2 diabetes mellitus (T2DM) who participated in two completed trials. Parameters reflecting the glycemic control, inflammatory factors, and fasting plasma lipids before and after intervention were measured, and the polymorphism of rs1799883 for each participant was genotyped using a MassARRAY. Differences between the genotypes of rs1799883 before or after the intervention were compared, and changes in the lipid profiles, glycemic control, inflammatory profiles, and dietary intake from baseline were analyzed using an analysis of covariance (generalized linear model).
Results: When the data were analyzed as a whole, after 4–5 weeks of similar low-GI diet intervention, we found that the decrease of triglycerides (TG) in the homozygous Ala54 carriers was more significant than that in the Thr54 allele carriers ([−0.58±1.24] vs [−0.14±1.08], P =0.015) with the adjustment for potential confounding factors; furthermore, compared with the Thr54 carriers, there was a significant trend in the decrease of total cholesterol (TC) in the homozygous Ala54 carriers (P =0.057). Subgroup analysis revealed that in women the homozygous Ala54 carriers exhibited a significant decrease of serum TG, TC, fasting blood glucose, and glycated albumin in women, but this was not noted in men.
Conclusion: The effect of FABP2  Ala54Thr polymorphism on response to blood lipids and glycemic control in low-GI diets is associated with gender among Han Chinese patients with T2DM.
Keywords: type 2 diabetes mellitus, plasma lipids, fatty acid-binding protein 2, single-nucleotide polymorphism, low glycemic index diet