Nutrition Under the Microscope

Genes, diet, and ethnicity all contribute to disease risk. African American men, for example, have a 60 percent greater risk of prostate cancer diagnosis and a 2 to 3 times greater mortality rate from prostate cancer than white males. Among Californians younger than 65, the asthma mortality rate for all African Americans is 2 to 4 times that of Caucasians, with African American children three times more likely to die from asthma than children of other ethnicities. Type 2 diabetes is another disease showing wide disparities in occurrence: 50 percent of adult Pima Indians have the disease, compared to 6.5 percent of Caucasian adults. Genetic differences alone cannot explain these disparities.

“Diet can be a serious risk factor for a number of diseases,” says Ray Rodriguez, PhD, professor of molecular and cellular biology at UCD and director of the center. “But in individuals, the exact effect of different components of food may depend on their genetic makeup. Some people are more severely affected by some kinds of diets than others. And nobody is protected from the harmful effects of all diets by his or her genes. It’s not a question of your genotype being good or bad—it just lets you interact with your environment in a certain way.”

The Center’s initial research program includes:

Lipids and Chronic Diseases Research Core
Director: Ronald Krauss, MD
High intakes of lipids and calories are associated with increased incidence and severity of chronic diseases, including diabetes, obesity, certain cancers, and cardiovascular diseases. Minority populations have disproportionately high incidences and morbidities of these chronic conditions. The overall objective of the Lipids and Chronic Diseases Research Core is to identify genes and genetic variations that interact with diet in determining biomarkers of risk in African Americans and Hispanics in comparison with Caucasians.

Micronutrient-Genomics Interactions Research Core
Co-Directors: Fernando Viteri, PhD, and Janet King, PhD
Over the past 20 years molecular biologists have shown that nutrients alter the milieu in which biochemical mechanisms operate and influence the relationship between genetics and health. The potential outcome of this core’s research is a better understanding of the role of dietary micronutrients in human disease. Current dietary guidelines focus primarily on micronutrient intake and do not consider genetic diversity among individuals. The ability to facilitate individualized dietary interventions based on the genetic make-up of individuals or population subgroups would increase the benefits of dietary change.

Immune Function and Inflammation Research Core
Co-Directors: Charles Stephensen, PhD, and Mark Shinegaga, PhD
The dramatic rise in childhood obesity in the United States is most prevalent in African-American and Hispanic youth. Studies have documented a consistent association between high body mass index and high levels of an acute phase protein produced by the liver in response to activation of the innate immune system. Hypothetically, high intake of cholesterol may play a role in inducing inflammation. Is it then possible that the link between obesity and chronic illnesses such as type 2 diabetes is mediated through the induction of inflammation? The studies in this core will investigate the role of Western diet in the development of the types of inflammation that seems associated with obesity.

Molecular Pathology Core
Director: Jeff Gregg, MD
The Molecular Pathology Core will centralize and streamline genomic and pathology services, such as gene expression profiling and genotyping, for members of the center. It will also provide consultation on design of experiments and train investigators on the use of data analysis programs.