Environmental factors are at least as important as genetic sequence in contributing to states of health and disease. Another interesting report on how chronic exposures to diet and activity (or lack thereof) contributes to insulin resistance via changes in gene regulation and expression comes out of a study of energy metabolism in identical twins discordant for obesity.
BETHESDA, Md. (June 18, 2008) A Finnish study of identical twins has found that physical inactivity and acquired obesity can impair expression of the genes which help the cells produce energy.
The findings suggest that lifestyle, more than heredity, contributes to insulin resistance in people who are obese. Insulin resistance increases the chance of developing diabetes and heart disease.
The study, ‚ÄúAcquired obesity and poor physical fitness impair expression of genes of mitochondrial oxidative phosphorylation in monozygotic twins discordant for obesity,‚Ä? appears in the online edition of the American Journal of Physiology-Endocrinology and Metabolism, published by The American Physiological Society.
The study was carried out by Linda Mustelin and Kirsi Pietil√§inen, of Helsinki University Central Hospital and the University of Helsinki; Aila Rissanen, Anssi Sovij√§rvi and P√§ivi Piiril√§ of Helsinki University Central Hospital; Jussi Naukkarinen, Leena Peltonen and Jaakko Kaprio, University of Helsinki and National Public Health Institute; and Hannele Yki-J√§rvinen of Helsinki University Central Hospital and Minerva Medical Research Institute.