Abstract
Women with polycystic ovary syndrome (PCOS) are markedly insulin-resistant, but the molecular mechanisms of these changes and their relationship to the hyperandrogenic state remain to be clarified. Mutations have recently been identified in the insulin receptor gene of patients with extreme forms of insulin resistance associated with hyperandrogenism (eg, type A insulin resistance), and these mutations account for the insulin resistance in such patients. We performed this study to determine whether mutations in the coding portion of the insulin receptor gene were responsible for insulin resistance in PCOS. Insulin binding studies using cultured skin fibroblasts of three obese (body mass index > 27 kg/m2) women with PCOS (ie, mild hyperandrogenemia and chronic anovulation of unknown etiology) and documented insulin resistance showed no apprarent abnormalities in either the number or affinity of insulin binding sites. Direct sequencing of all 22 exons of the insulin receptor gene from two of the women with PCOS did not reveal any mutations. Furthermore, both alleles of the gene were expressed at equal levels. In a third insulin-resistant PCOS woman, there was no evidence for a mutation in the coding portion of the insulin receptor gene as determined by denaturing gradient gel electrophoresis (DGGE). We conclude that the insulin resistance in these PCOS women was caused by a defect extrinsic to the insulin receptor.
Original language | English (US) |
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Pages (from-to) | 1568-1574 |
Number of pages | 7 |
Journal | Metabolism |
Volume | 43 |
Issue number | 12 |
DOIs | |
State | Published - Dec 1994 |
Funding
From the Department of Medicine, Division of Endocrinology, Diabetes, and Metabolism, Pennsylvania State University College of Medicine, Hershey, PA; the Depatiment of Medicine, Division of Endocrinology, and the Department of Biochemisiv, Mt. Sinai School of Medicine, New York, NV; and the National Institute of Diabetes and Digestive and Kidney Diseases, Diabetes Branch, National Institutes of Health, Bethesda. MD. Submitted November 17, 1993; accepted March I, 1994. Supported by grants ffom the National Institutes of Health (ROI DK40605; A.D.), the American Diabetes Association (A.D.), and Phillip Kingsley, Ltd (A.D.). Address reprint requests to Andrea DunaiJ MD, Pennsylvania State University College of Medicine, Division of Endocrinology, Diabetes, and Metabolism, PO Box 8.50, 500 University Dr, Hershey, PA 17033. Copyright 0 I994 by W B. Saunders Company 0026-0495/94/4312-0018$03.OOiO
ASJC Scopus subject areas
- Endocrinology
- Endocrinology, Diabetes and Metabolism