You are what you experience

I was talking to a clinical researcher about genes and I learned something interesting.

As you learned in elementary school, every gene in your body contains a full replica of your DNA. When a cell splits, your RNA will duplicate your DNA to place it in the new cell. What is fascinating about this step is that your RNA gets to determine which genes in your DNA get expressed. Genes that are not expressed do not affect the cell they are in, so essentially parts of your DNA get ignored. So that family history of X, Y, and Z your parents have told you about may exist in your DNA, but those problems may never be expressed because of how your RNA express them.

So why doesn't the RNA just remove cancer and those other genes? Well, the body is very complex, and those genes were a result of mutations over hundreds of millennia and were at some point in your DNA for a reason. So whatever physiological event that results in your RNA expressing some genes over others is a result of millions of years of evolution, and while the genes may be vestiges now, odds are those genes were valuable at some point.

Now, it gets even cooler. What genes your RNA express is determined by what you are doing right now. That coffee you are drinking, the deflection of sunlight off the wall hitting your skin, and the slightly increased CO2 levels in the air are all affecting you this second. Your RNA is expressing genes that have to do with the exact environment you are in. So when you start a new diet or begin to work out, your body will begin changing immediately. As you know, there are trillions of cells in your body. In order for these changes to rack up you need to do them consistently, so you don't see changes for a while. But they are there.

If you smoke one time, your body will begin to express different genes as a result of the smoking, but some time after you finish smoking your RNA will go back to expressing the genes it normally does. The cells created while smoking stays in your body, but they never build up, so it never really takes an effect. But that 30 minutes a day you spend meditating has lead to a pretty large physiological change. For 30 min every day, your RNA has been expressing genes as a result of your meditative state. At the beginning, these changes were a few in trillions (like when you smoked), but due to consistency, it’s starting to amount to a fairly large amount of cells. A substantial minority of you is now different.

The wildest part is that these changes can also affect your gametes, so essentially every action you take before you have kids goes into affecting them. Through proper diet and exercise, you can “erase” certain genes from your family tree if the piece of your DNA copied into your gamete lacks the gene. This gives your kin a set of DNA with more positive genes and less negative ones for their RNA to choose between. We are just scratching the surface of understanding genetics, but none the less, the little we know is extraordinary.