The GEMM Family Study
  • Country  Mexico

    GEMM stands for Genética de las Enfermedades Metabólicas en México (Genetics of Metabolic Diseases in Mexico). GEMM is a newly-established, multi-center collaborative study of the genetic epidemiology of the metabolic syndrome, a complex of disorders related to type 2 diabetes, obesity and the risk of cardiovascular disease.  The scientific oversight of GEMM is provided by members of the Department of Genetics at the Texas Biomedical Research Institute, located in San Antonio, Texas. My University in Monterrey, Mexico has established strong collaborative connections with our colleagues from Texas to develop the GEMM study. I serve as the research coordinator and Co-PI in Monterrey. My task is to oversee the recruitment of individuals in extended families. Volunteers are brought into a dedicated diagnostic facility at the Metropolitan Hospital in Monterrey, to provide a medical history, be measured on a variety of anthropometric and other clinical traits relevant to metabolic diseases, provide a blood sample for biochemical analysis and DNA for genotyping, biopsies of subcutaneous fat and muscle as a basis for genome-wide expression profiling, and postprandial measurements after a mixed meal. The entire study is projected to take 3-5 years.

    The aim of this project is to study gene expression before and after a well-defined meal to characterize normal variation in postprandial metabolism. This expression profiling is expected to find genes contributing to the metabolic flexibility of individuals in the Mexican population, by utilizing the latest advances in genomic science focused on studies based on an integrated systems approach to human biology. Such a focus on the genetic response following the consumption of a nutritionally defined meal at the level of the specific tissues involved (i.e., fat and muscle), will produce new insights into the genetic architecture of individual variation in metabolism of carbohydrates, fats and proteins, and how this variation in response relates to risk for a variety of chronic diseases including obesity, diabetes and heart disease.

    Our first preliminary data has been accepted to be published in the newest journal from The American Society for Nutrition (ASN) called Advances in Nutrition, launched November 16, 2010, in response to the growing demand for a prestigious, high-profile publication that gathers the current state of knowledge in all facets of the field.

    The basis of our paper stems from the novel study of transcriptomics, also referred to as expression profiling, which examines the expression level of mRNAs in a given cell population or tissue. Gene expression measurements reflect quantitative variation in transcript-specific mRNA levels and represent phenotypes lying close to the action of genes. We were able to obtain synchronous in-vivo expression profiles of lymphocytes, muscle, and subcutaneous fat from healthy Mexican men. Our results showed that most genes were expressed at detectable levels in multiple tissues, and RNA levels were correlated between tissue types. A subset of transcripts with high reliability of expression across tissues (estimated by intraclass correlation coefficients) was enriched for cis-regulated genes, suggesting that proximal sequence variants may influence expression similarly in different cellular environments.  

    We concluded that understanding the genetic basis of gene expression will provide insight into the processes that connect genotype to clinically significant traits representing a central tenet of system biology. In addition to the international benefits of the GEMM Family Study to both Mexico and the United States in terms of biomedical research and health care, the study is structured to enhance the scientific capacity of my University, by providing technical training and research opportunities for local students in collaborative projects using GEMM data.


    Edna J. Nava-González, Certified Nutritionist 
    Ph.D. Student in Nutrition and Genetics
    Public Health and Nutrition School, Nuevo Leon State University
    Mexican College of Nutrition, Nuevo Leon Chapter
    Monterrey, Mexico.