Berman Peter, Collins Malcolm, Baumgarten Ingrid, Seoighe Cathal, Jennings Courtney L, Joffe Yael, Lambert Estelle V, Levitt Naomi S, Faulenbach Mirjam V, Kahn Steven E, Goedecke Julia H
Division of Chemical Pathology, UCT/MRC Research Unit for Exercise Science and Sports Medicine, Department of Human Biology, University of Cape Town, Cape Town, South Africa.
Obesity (Silver Spring). 2009 Jun;17(6):1298-300. doi: 10.1038/oby.2009.40. Epub 2009 Feb 26.
The objective of the study was to examine the association between a functional 4 bp proinsulin gene insertion polymorphism (IVS-69), fasting insulin concentrations, and body composition in black South African women. Body composition, body fat distribution, fasting glucose and insulin concentrations, and IVS-69 genotype were measured in 115 normal-weight (BMI<25 kg/m2) and 138 obese (BMI>or=30 kg/m2) premenopausal women. The frequency of the insertion allele was significantly higher in the class 2 obese (BMI>or=35 kg/m2) compared with the normal-weight group (P=0.029). Obese subjects with the insertion allele had greater fat mass (42.3+/-0.9 vs. 38.9+/-0.9 kg, P=0.034) and fat-free soft tissue mass (47.4+/-0.6 vs. 45.1+/-0.6 kg, P=0.014), and more abdominal subcutaneous adipose tissue (SAT, 595+/-17 vs. 531+/-17 cm2, P=0.025) but not visceral fat (P=0.739), than obese homozygotes for the wild-type allele. Only SAT was greater in normal-weight subjects with the insertion allele (P=0.048). There were no differences in fasting insulin or glucose levels between subjects with the insertion allele or homozygotes for the wild-type allele in the normal-weight or obese groups. In conclusion, the 4 bp proinsulin gene insertion allele is associated with extreme obesity, reflected by greater fat-free soft tissue mass and fat mass, particularly SAT, in obese black South African women.
该研究的目的是探讨功能性4碱基对胰岛素原基因插入多态性（IVS - 69）、空腹胰岛素浓度与南非黑人女性身体成分之间的关联。对115名体重正常（BMI<25 kg/m²）和138名肥胖（BMI≥30 kg/m²）的绝经前女性测量了身体成分、体脂分布、空腹血糖和胰岛素浓度以及IVS - 69基因型。与体重正常组相比，2级肥胖（BMI≥35 kg/m²）人群中插入等位基因的频率显著更高（P = 0.029）。携带插入等位基因的肥胖受试者比野生型等位基因纯合子肥胖者有更大的脂肪量（42.3±0.9 vs. 38.9±0.9 kg，P = 0.034）和去脂软组织量（47.4±0.6 vs. 45.1±0.6 kg，P = 0.014），以及更多的腹部皮下脂肪组织（SAT，595±17 vs. 531±17 cm²，P = 0.025），但内脏脂肪无差异（P = 0.739）。携带插入等位基因的体重正常受试者仅SAT更大（P = 0.048）。在体重正常或肥胖组中，携带插入等位基因的受试者与野生型等位基因纯合子之间的空腹胰岛素或血糖水平无差异。总之，4碱基对胰岛素原基因插入等位基因与极度肥胖有关，表现为肥胖的南非黑人女性有更大的去脂软组织量和脂肪量，尤其是SAT。
