Anyone still laboring under the mistaken assumption that genes are the most important factor in determining destiny should take a look at research that is being reported in this week’s Science about a particular strain of mice that have a genetic predisposition to develop type 1 diabetes. It turns out that a key element in whether or not they actually succumb to the condition has to do with the type of bacteria that live in their intestines. The results reveal a complex interplay between gut bacteria (part of the animal’s microbiome), genes and, surprisingly, sex hormones.
Type 1 diabetes is the form of the disease in which the body’s immune cells launch a self-destructive attack on the pancreas, obliterating the organ’s ability to secrete insulin. (Such dysfunctional immune responses are the basis of autoimmune disorders in people as well as mice.) By transplanting specific gut bacteria from one group of mice to another (don’t ask), the investigators, who hailed from Canada, the U.S., Germany, Denmark and Switzerland, were able to prevent some of the rodents from developing diabetes.