PPAR(gamma)2 gene Pro12Ala polymorphism may influence serum level of an adipocyte-derived protein, adiponectin, in the Japanese population.

Adiponectin is an adipocyte-derived protein, which possesses an anti-atherosclerotic action and improves insulin sensitivity. Peroxisome proliferator-activated receptor gamma (PPAR(gamma)) regulates the transcription of many adipocyte-specific genes. A Pro12Ala polymorphism has been detected in the PPAR(gamma)2 gene, and this substitution has been reported to reduce transactivation activity in vitro. We hypothesized that individuals possessing this Ala12 allele may have a lower serum adiponectin level, because of the observation that PPAR(gamma) agonists increase the plasma adiponectin level in humans. To test this hypothesis, we investigated the effects of the PPAR(gamma)2 Pro12Ala polymorphism on anthropometric and metabolic parameters, including serum adiponectin level, in 478 Japanese men and 117 women aged 30 to 65 years. There were no homozygous subjects for the Ala12 allele of the PPAR(gamma)2 gene in this study. Plasma adiponectin levels were significantly lower in subjects with the Ala12 allele in the Japanese population of both sexes, although body mass index (BMI), plasma glucose, serum lipids, and insulin resistance index were not significantly different between subjects with and without this polymorphism. It is suggested that the Pro12Ala polymorphism of the PPAR(gamma)2 gene may reduce serum adiponectin level in the Japanese population.