Pro12Ala polymorphism of the peroxisome proliferatoractivated receptor-gamma gene is associated with metabolic syndrome and surrogate measures of insulin resistance in healthy men: interaction with smoking status.
BACKGROUND
The Pro12Ala polymorphism (rs1801282), a nonsynonymous substitution of peroxisome proliferator-activated receptor-gamma (PPARG), has been robustly associated with type 2 diabetes. However, its role in metabolic syndrome (MetS) remains poorly understood. The associations among rs1801282, MetS and surrogate measures of insulin resistance (IR) were investigated in the present study.


RESULTS
A cross-sectional population-based survey of 572 unrelated healthy male Argentinian blood donors with normal findings on medical examination and not taking any medication was conducted. MetS was assessed using the National Cholesterol Education Program/Adult Treatment Panel III (NCEP/ATP III) criteria, and the HOMA-IR, and QUICKI were calculated. Genotyping of rs1801282 was performed using RFLP-PCR. The prevalence of MetS was 26.2%. The Pro/Ala genotype (and the Ala12 allele) was associated with a high risk for MetS (odds ratio (OR) 1.67 [95% confidence interval (CI) 1.03-2.72], P=0.0394). This was highlighted among nonsmokers (OR 2.20 [95%CI 1.25-3.88], P=0.0059). ANCOVA confirmed an interaction between smoking status and this association (P=0.031). Ala12 carriers had a higher waist circumference than noncarriers (P=0.0065). Among nonsmokers, surrogates of IR, such as HOMA-IR, were significantly higher in Ala12 carriers than in noncarriers (P<0.05).


CONCLUSIONS
Healthy men, in particular nonsmokers, carrying the Ala12 allele of PPARG rs1801282 polymorphism, have a high risk for MetS and IR.
Tellechea
Mariana L
ML
Laboratory of Molecular Biology, Department of Genetics and Molecular Biology, School of Pharmacy and Biochemistry, University of Buenos Aires, Buenos Aires, Argentina.
Aranguren
Florencia
F
Pérez
María Silvia
MS
Cerrone
Gloria E
GE
Frechtel
Gustavo D
GD
Taverna
Mariano J
MJ
D000293:Adolescent; D000328:Adult; D000368:Aged; D000483:Alleles; D019943:Amino Acid Substitution; D001118:Argentina; D001782:Blood Donors; D003430:Cross-Sectional Studies; D005787:Gene Frequency; D006801:Humans; D007333:Insulin Resistance / Q000235:genetics*; D008297:Male; D024821:Metabolic Syndrome / Q000235:genetics*; D008875:Middle Aged; D009765:Obesity / Q000235:genetics; D050177:Overweight / Q000235:genetics; D047495:PPAR gamma / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide; D012307:Risk Factors; D012907:Smoking / Q000235:genetics*; D055815:Young Adult
D047495:PPAR gamma