We are not slaves to our genes. Even if we are born with an inherited predisposition to obesity, life style is important and will determine the outcome of weight related problems says this recent study in the American Journal of Clinical Nutrition.
Several studies have found that exercise diminishes the effect of the risk gene, but a new study is the first to study the effect of the gene in relation to food habits. The risk variant of the FTO gene is common in the general population. 17 percent have double copies, meaning they have inherited it from both parents. Another 40 percent have a single copy.
But genes determine our life, and health don’t they? The Mendellian concept of pre-determined genetic risks have been seriously challenged over the last few years as scientists discover that genetic expression – The translation of information encoded in a gene into protein or RNA is influenced by our environment especially foods. This is a new science and is referred to as nutrigenomics. Two leading genetic researchers from the Department of Human Genetics and Pediatrics, David Geffen School of Medicine at UCLA gave a revealing quote about our DNA:
Your genome, or any part of it, is not you. The concept that our DNA sequence our genome- does not equal or predict our destiny has been extremely difficult for some geneticists to accept. We don’t even have a good idea how many genes there are, let alone how these genes work with each other and the environment to orchestrate human development.
LL McCabe & ERB McCabe. DNA Promise and Peril. University of California Press; 1 edition (1 Mar 2008)
The information for this paper comes from the large Malmö Diet and Cancer study where food habits were carefully documented using, among other things, an extensive questionnaire, a long interview and a food diaries kept by the participants themselves. When the eating habits of the carriers of the double risk variant for obesity was analysed the pattern was clear. The risk of obesity was dramatically increased only in the case of high fat consumption.
“…for those who had a diet where less than 41 percent of the energy consumed came from fat, obesity was not more common, in spite of the inherited risk” says Lead Author Emily Sonestedt.
Comment
Diet rather than genes determines the risk for obesity in the case of the FTO gene, and will most likely be the same when additional genes are identified. In summary we are not prisoners of our genetic make up, we are free to select foods and environmental triggers to either suppress or express their hidden codes.
Sonestedt, Emily, Roos, Charlotta, Gullberg, Bo, Ericson, Ulrika, Wirfalt, Elisabet, Orho-Melander, Marju. Fat and carbohydrate intake modify the association between genetic variation in the FTO genotype and obesity. American Journal of Clinical Nutrition, 2009; DOI: 10.3945/ajcn.2009.27958
