Understanding SNPs Using “I Love Lucy”
One of the major challenges in my practice is relaying information about single nucleotide polymorphisms (SNPs) in a way that’s accessible and empowering for my patients. The acronyms alone make it daunting to approach: MTHFR, COMT, MAO, VDR, UGH (okay, that last one was mine). Genomic medicine can be a powerful tool for improving and optimizing health, so with that in mind, let’s try to decode the alphabet soup.
My favorite analogy for explaining SNPs comes from an episode of I Love Lucy called “Job Switching.” In the famous episode, Lucy and Ethel get jobs on a factory line wrapping chocolates. Being amateurs, they can’t quite keep up with the pace of the conveyer belt. As chocolates slip past and they grow increasingly desperate to keep up, the ladies begin shoving chocolates in their mouths, down their shirts, and everywhere else to prevent unwrapped chocolates from continuing down the line to the next worker. It’s slapstick at its best, and also provides a helpful mental image.
Molecules are made and used by every cell in our body to drive every bodily function (metabolism, digestion, hormone signaling, etc.). Each molecule is made from precursors by a series of enzymes. Molecules are like the chocolates, starting as raw ingredients that step-by-step get turned into the packaged final product. Enzymes are like the factory workers, each one doing a small step in the assembly line over and over.
SNPs are genetic glitches that make our enzymes slower and clumsier, like Lucy and Ethel. When one enzyme is inefficient, it prevents the assembly line from running quickly and smoothly. Fewer final products are produced, and more half-finished intermediates persist (stuffed in our enzymes’ blouses).
The problem can be made worse by inappropriate supplementation. For example, people with the MTHFR SNP are less efficient at activating their B vitamins (particularly folic acid and B12) for energy, DNA production, and many other important functions. Supplementing these individuals with B vitamins in their inactive state is like speeding up the conveyer belt on Lucy and Ethel; not only will there not be more finished molecules, but there will be more half-finished intermediates lying around.
Does having a SNP mean someone is forever doomed to taking a specific (and often costly) supplement? Not at all! Lucy and Ethel were fine at their job when the conveyer belt moved at a pace they could handle, and the same is true for our inefficient enzymes. If we reduce the burden on the enzymes by eating clean foods, breathing fresh air, exercising, reducing stress, and sleeping well, then often temporary supplementation is all that’s needed until the system works more harmoniously.
It’s also important not to look at SNPs in isolation. In the chocolate factory, a handful of raw ingredients are used to make one final product. In the human body, there are hundreds of interconnected conveyer belts making thousands of unique molecules. If we address one SNP without looking at the bigger picture, it can sometimes cause unexpected side effects by revealing SNPs in a connected pathway. If you decide to do a SNP analysis, it is highly recommended you do it under the guidance of a practitioner experienced in genomic medicine.
