Gut flora and cognition
October 26, 2012
You may already know this, but I was surprised to hear that the microbes living in an on our bodies outnumber our own cells 10 to 1 and collectively contain orders of magnitude more genetic information. I guess that’s not necessarily saying much since the common potato has almost twice as many genes as a human. There is actually a huge effort in the EU to sequence the DNA of the human microbiome called MetaHIT.
MetaHIT discovered that there are 3, err 2 distinct microbiome population types callled enterotypes. One enterotype is dominated by the Bacteroides genus of microbes and is related to high fat or protein diets. This the one a lot of fat people have. The Prevotella enterotype is characterized by high carb diets and I assume is related to better metabolic health.
Gut flora have been implicated in everything from mood regulation to diabetes. The fecal transplant stories are pretty freaky too. This is a treatment for bacterial infections (primarily Clostridium difficile?) that involves transferring fecal matter from a healthy relative into the colon of a person desperately ill with a bacterial infection. Once the gut flora is fixed, it takes care of the other bad bugs hanging around. Some people also think there might be a connection between autism and gut flora problems.
I don’t want to get all Larry Smarr about it, but I am interested in getting my gut flora sequenced. So I joined this study on the Genomera citizen science platform organized by the smart and cool Melanie Swan: Microbiome Profiling Response to Probiotic in a Healthy Cohort. Here is the description:
Critical to digestive health, the microbiome is a newly available personal health data stream. Join this first-ever participant-organized citizen science microbiome project! Second Genome will provide microbiome sequencing to analyze potential shifts in the gut microbiome before and after 4 weeks of a daily dose of an OTC probiotic such asCulterelle® (Lactobacillus GG). A personalized report will be provided to each participant with the global shift in microbiome bacterial abundance by individual and study group, and a personalized profile of ratios pre and post intervention of Firmicutes, Bacteroidetes, Helicobacter pylori, and the most abundant 10-15 bacterial taxa at the phylogenetic family level (DRAFT of sample report). Human genetic SNPs related to Ulcerative Colitis andCrohn’s Disease are optionally requested to see if they may have a connection with microbiome profiles.
It’s $800 for the sequencing from Second Genome (which I hear is a good price) and I encourage anyone interested to join up. We need more people to join before we can begin the study, so spread the word. Check out Melanie’s blog when you get a chance, she covers a lot of QS, Futurist, and other modern topics.
Sorry, I know the title is Gut Flora and Cognition, but I don’t have much to say on that since the data isn’t in yet. I suspect he work on mood or autism might pan out. Those are cognitive things. Also, I intend to recommend people track their cognitive performance with Quantified Mind during the probiotic study to see if this gut intervention makes you smarter or stupider. Though I think that this article makes a good point when the author questions “the ability of a single strain of bacteria to impact on the vast inner ecosystem of the human gut.” So a tiny dose of just a few strains of bacteria taken orally seems unlikely to have much impact. Still, we shall see, we shall see.