Many of our center’s researchers seek to understand the genetic influence on diabetes, obesity, and metabolic disorders. Through studies in many cases originating at Northwestern University, we have help identify genetic links to these diseases, leading to new insights and research directions. Learn more about our current work below.
Labs in This Research Area
Genetic and molecular basis of Polycystic ovary syndrome (PCOS)
Polycystic ovary syndrome (PCOS) is the most common cause of both hormonal-related infertility and oligomenorrhea. This syndrome is characterized by increased androgen biosynthesis and disordered gonadotropin secretion. PCOS is also associated with profound insulin resistance and increased risk for type 2 diabetes. PCOS, and the insulin resistance associated with it, appear to be genetic defects. Moreover, insulin resistance plays a causal role in the abnormalities of ovarian steroidogenesis as well as the anovulation characteristic of PCOS. There are three major research projects currently ongoing, ranging from large-scale family studies through intensive patient-oriented research to animal models and cellular and molecular biology.
The Genetic Basis of PCOS
This research program focuses on identifying the susceptibility genes for PCOS, performing genotype-phenotype analyses and identifying environmental and genetic factors contributing to PCOS familial phenotypes. Studies include family studies with linkage analysis and detailed analyses of reproductive function and insulin action in women with PCOS and their relatives. The approaches include statistical genetics and in vivo studies of insulin action and secretion, as well as pulsatile gonadotropin secretion. One susceptibility gene region has been identified on chromosome 19p13.2 close to the insulin receptor gene. This research is supported by the NIH-NICHD National Cooperative Program for Infertility Research.
Insulin Action and Secretion in PCOS
These studies are focused on identifying the cellular and molecular mechanisms of defects in insulin action and secretion in PCOS. Approaches include detailed in vivo studies of these parameters utilizing techniques such as the euglycemic glucose clamp, frequently sampled intravenous glucose intolerance test with minimal model analysis and graded glucose infusions. Insulin receptor signal transduction is examined in human skeletal muscle biopsies, as well as in human skeletal muscle and adipocyte cultures. Intrinsic defects in insulin receptor signaling have been identified and the mechanisms of these abnormalities are currently under investigation. These studies are supported by an NIH-NICHD-ORWH Specialized Center of Research (SCOR) on Sex and Gender Factors Affecting Women’s Health.
Fetal Origins of PCOS
These studies examine the impact of prenatal androgen exposure on insulin action in rodent, primate and sheep models. Studies include examination of lipolysis and insulin signaling in skeletal muscle and adipose tissue and the molecular mechanism of fetal programming. These studies are supported by an NIH-NICHD-ORWH Specialized Center of Research (SCOR) on Sex and Gender Factors Affecting Women’s Health.
Scholars will have the opportunity to become involved in phenotype-genotype studies of PCOS families with a strong exposure to the genetics of complex diseases.
For more information, please see Dr. Dunaif's faculty profile.
See Dr. Dunaif's publications in PubMed.
Susceptibility genes for complex diseases
Dr. Urbanek’s research focuses on the identification of susceptibility genes for complex diseases. Her approach to this research is to use family-based gene-mapping techniques and population-based association studies in conjunction with molecular techniques to identify and verify genes and pathways contributing to the pathogenesis of genetically complex diseases. Specifically, she is carrying out studies to identify susceptibility genes for polycystic ovary syndrome (PCOS) that map to Chr19p3.13. She has previously shown that this region shows linkage and association with PCOS in a large set of families. Other projects focus on identifying candidate genes for gestational diabetes and glycemic control during pregnancy and identifying genetic variation contributing to extreme obesity
Identification of sequence variants in PCOS candidate genes
Identification of candidate genes for contributing glycemic control during pregnancy and to gestational diabetes
Genetic variation contributing to extreme obesity
Linkage and family-based association studies
Genome-wide association studies
For more information, visit Dr. Urbanek's faculty profile page.
View Dr. Urbanek's publications at PubMed.