The Obesity Puzzle: A Missing Piece
As obesity has become a leading cause of preventable death worldwide, scientists have labored assiduously to untangle the disease’s dense snarl of root causes. Thanks to these efforts, excess consumption of unhealthy foods, today’s more sedentary lifestyles, and a number of environmental factors have been isolated as likely, if not certain, culprits.
What’s still lacking, however, is a clear understanding of how the genetic information packed into our cell nuclei — all else being equal — makes us more or less likely to be overweight. Certainly obesity seems to run in families, but a fine-grained picture how of exactly it is that microscopic interactions involving DNA translate to larger-scale health and behavioral outcomes has remained elusive.
Needless to say, a fleshing out of the genetics underlying our expanding waistlines would be a great help to doctors and other public health experts in their quest to improve human health.
One Step Closer
Thanks to a recent collaboration between a team of researchers from the University of Southern California Los Angeles and a large, varied group of laboratory mice, it seems some progress has been made.
In order to gauge how genes impact how individual mice process fat and sugar differently, scientists alternated between giving the animals relatively healthy and relatively unhealthy meals, keeping tabs on each mouse’s fat levels along the way. Because mouse strains were interbred, scientists were also able to narrow down which genes were likely responsible for different results.
What they found is that the effects of high-sugar and high-fat diets fluctuated widely from strain to strain. While some mice became severely obese, suffering body fat increases of some 600 percent, others grew hardly at all. This is strongly suggestive of a causal link between a given animal’s genetic profile and it’s propensity to convert excess lipids and carbohydrates into excess body fat.
The results were published in the journal Cell Metabolism.
Of course, humans are not mice, and it remains to be seen just how this correlation between genes and metabolism will find practical application in the management of obesity in people.
Still, due to similarities in the genetic codes of Mus musculus and Homo sapiens, scientists are optimistic that new genetically-informed treatments will eventually emerge.