PPARD rs2016520 polymorphism is associated with metabolic traits in a large population of Chinese adults

Aims: Polymorphism of rs2016520 in gene PPARD has been associated with lipid metabolism, obesity, metabolic syndrome and type 2 diabetes mellitus (T2DM). We aimed to study the association of rs2016520 with common metabolic traits in a large population of Han Chinese adults.

Methods: The polymorphism was genotyped in 1409 subjects using Matrix-Assisted Laser Desorption/Ionization Time of Flight Mass Spectrometry (MALDI-TOF MS); all participants underwent standard clinical examination and a 75g oral glucose tolerance test (OGTT); associations between the polymorphism and metabolic traits and indices of insulin resistance and insulin sensitivity were analyzed.

Results: There was no significant difference in genotypes between the normal glucose tolerance (NGT) and the prediabetes group (χ(2)=3.17, P=0.2), except a nominal difference of allele frequency (χ(2)=3.07, P=0.07). The G carrier presented lower fasting plasma glucose (FPG, P=0.03), lower 2h plasma glucose (Pdom=0.04) and lower fasting insulin (P=0.02), lower systolic blood pressure (SBP, P=0.03), lower HOMA-IR (P=0.02) and higher QUICKI (P=0.01). Moreover, rs2016520 polymorphism was associated with FPG (β=-0.09, P=0.05), it was also associated with indices of insulin resistance (HOMA-IR, β=-0.06, Pdom=0.02; fasting insulin, β=-0.04, P=0.02) and indices of insulin sensitivity (QUICKI, β=-0.01, P=0.004). In addition, we observed that the allele G was also associated with lower SBP (β=-1.29, P=0.04) and diastolic blood pressure (DBP, β=-0.09, P=0.01). However, the minor allele G was not associated with risk of metabolic disorders including prediabetes, overweight, hypertension and metabolic syndrome.

Conclusions: Polymorphism of rs2016520 in gene PPARD was associated with benign metabolic traits in a large cohort of Chinese adults. The G allele may confer protection from type 2 diabetes and hypertension in Han Chinese.