The A-3826G gene polymorphism of the uncoupling protein 1 (UCP1) causes the lower expression of UCP1 in visceral fat and reduced energy expenditure. Peroxisome proliferator activated receptor gamma 2 (PPARG2) plays a role in the regulation of the adipocyte differentiation and energy balance. The Pro12Ala polymorphism is associated with better insulin sensitivity. We compare the genotypic distribution of these polymorphisms in PCOS and controls and study their possible association with screened biochemical and anthropometric parameters.
After signing written informed consent, 142 PCOS (median of age 27) and 114 controls (median of age 27.2), biochemically and anthropometrically characterized, underwent the oGTT and 50 PCOS euglycemic hyperinsulinemic clamp. The polymorphisms were detected by PCR-RFLP; statistics with NCSS 2000.
The genotype frequencies in PCOS and controls were: UCP1 AA: 53 % vs. 49.5 %; AG: 39 % vs. 40 %, GG: 8 % vs. 10.5 %, PPARG2 PP: 79 % vs. 76 %, PA: 17 % vs. 23 %, AA: 4 % vs. 1 %. Despite the fact that PCOS had significantly higher androgene and lipid levels, BMI, WHR, fasting and stimulated blood glucose and insulin, lower SHBG, 1/HOMA R, Matsuda and QUICKI indices in comparison with controls, the genotypic frequencies did not differ between the groups. Even though the higher BMI in G allele carriers in the controls was apparent (UCP1 AA vs. AG p=0.03, AA vs. GG p=0.02), this trend was not found in the PCOS. Pro12Ala polymorphism of PPARG2 was not associated with better insulin sensitivity.
Conclusions: The frequency of the risk polymorphisms of UCP1 (A-3826G) or PPARG2 (Pro12Ala) was not different between PCOS and healthy women and their occurrence was not associated with body adiposity or insulin sensitivity.
The Ethical Committee of Institute of Endocrinology approved the protocol.
Supported by grant No. 301/04/1085 GACR
04 - 06 Apr 2005
British Endocrine Societies