Genetic variants in peroxisome proliferator-activated receptor-γ and retinoid X receptor-α gene and type 2 diabetes risk: a case-control study of a Chinese Han population.

Abstract

BACKGROUND:

The serum levels of adiponectin are paradoxically decreased in obesity and may play important roles in the development of type 2 diabetes mellitus (T2DM). Potentially functional polymorphisms in the peroxisome proliferator-activated receptor-γ (PPAR-γ) and retinoid X receptor-α (RXR-α) genes may alter T2DM risks by increasing the human adiponectin promoter activity in cells. Therefore, we hypothesized that single nucleotide polymorphisms (SNPs) in PPAR-γ and RXR-α were associated with risk of T2DM. To test this hypothesis, three potentially functional SNPs of PPAR-γ and four of RXR-α with a minor allele frequency of ≥ 0.05 in the Chinese Han population were identified from the National Center for Biotechnology Information dbSNPs database to evaluate their association with T2DM.

METHODS:

Polymerase chain reaction-restriction fragment length polymorphism was performed to test the genotypes in T2DM patients (n = 540) and normal controls (n = 604).

RESULTS:

The variant genotypes rs2920502CC, rs3856806CT, rs3856806CT/TT, and rs4240711AG/GG were associated with T2DM. Furthermore, the prevalences of haplotype GTC and CTG in PPAR-γ and GTAC in RXR-α were less frequent in cases (17.1%, 2.6%, and 2.4%, respectively) than in controls (22.3%, 3.8%, and 6.6%, respectively), whereas GTGT in RXR-α was more frequent in cases (6.9%) than in controls (4.4%) (P < 0.05 for both two-sided χ(2) test and thousand times permutation tests). Patients with genotype CT/TT of rs3856806 and genotype AG/GG of rs4240711 had higher levels of serum adiponectin than those with the genotype CC and genotype AA (P = 0.026 and 0.021, respectively). Model X2 X5 X6 X7 (rs3856806, rs3132291, rs4240711, and rs4842194) was the best model with the highest test balanced accuracy (0.5764) (cross-validation consistency = 10/10) in the multifactor dimensionality reduction method.

CONCLUSIONS:

The PPAR-γ and RXR-α gene variants associated with the development of T2DM in this study must be investigated in a larger population to reveal any potential effects on metabolism.

• Authors: Ying Lu, Xinhua Ye, Yuanyuan Cao, Qian Li, Xiaofang Yu, Jinluo Cheng, Yanqin Gao, Jianhua Ma, Wencong Du, Ling Zhou
• Journal: Diabetes technology & therapeutics (Diabetes Technol Ther) Vol. 13 Issue 2 Pg. 157-64 (Feb 2011) ISSN: 1557-8593 [Electronic] United States
• PMID: 21284483 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• Adiponectin
• PPAR gamma
• Retinoid X Receptor alpha

Topics

• Adiponectin (blood)
• Aged
• Asian People (genetics)
• Body Mass Index
• Case-Control Studies
• China
• Databases, Genetic
• Diabetes Mellitus, Type 2 (blood, ethnology, genetics)
• Female
• Gene Frequency
• Genetic Association Studies
• Humans
• Linkage Disequilibrium
• Male
• Middle Aged
• Multifactor Dimensionality Reduction
• PPAR gamma (genetics)
• Polymorphism, Single Nucleotide
• Retinoid X Receptor alpha (genetics)