Blame it on our genes — the blueprint for life that we inherit without having any say in the matter. We have been led to believe that you can’t change your genes, and thus we are destined to inherit certain traits. It turns out this is not entirely true. We can’t change the blueprint, but we do have enormous control over which parts of the plan get implemented.
The genome is the sum total of all our genes, which layout the plans for building and maintaining every aspect of life. There are over 20,000 genes within the human genome and those genes are made up of strings of information encoded in the DNA double helix. Individual genes code for the production of various proteins, some of which become structure such as bone or flesh, with others that function as enzymes promoting chemical reactions. The expression of all these various proteins is what controls the body and one’s overall health.
Our genome is inherited from our ancestors, most directly from our parents of course and can’t be changed. However there is tremendous influence by external factors on which genes are expressed. That is, some can be turned on, and some can be turned off. These “switches” can be controlled by forces aside from the genome, or above the genome if you will, leading to the term “epi” genetics.
During fetal development the genome progressively gets it’s original epigenetic marching orders through a set of “bookmarks” that establish which genes are turned on or off. These marks are influenced by exposures in the womb and seem to be set during adult life, but they can be tweaked by environmental impacts, good or bad.
Turning Genes On and Off
The main process that affects epigenetic bookmarks is called methylation, in which a chemical “methyl” group is attached to certain points in the gene. Adding a methyl group directly to the DNA tends to turn off a gene, and the absence of a methyl group allows the gene to be expressed.
A second major influence on gene expression involves bundles of proteins called histones, which cause the DNA double helix to cluster into a little balls and hide it’s code. Again, the attachment of methyl groups to the histones tends to discourage the DNA from uncoiling and expressing its code.
Up until recently most of the focus on methylation and epigenetics has been on heart disease and cancer, but we are also learning it has a profound implication in many mental illnesses, such as depression, autism, bipolar, and even schizophrenia. Chronic fatigue syndrome seems to have an epigenetic component for many people.
The good news, actually overwhelmingly great news if you think about it, is that one can influence the expression of your genes and to some extent compensate for aberrant bookmarks. For example, schizophrenia is caused by an excess amount of an excitatory neurotransmitter called dopamine. The medications used to treat this disorder block dopamine activity. It is well established that in many schizophrenic patients, simply adding large amounts of Vitamin B3 (niacin) supplements will cause the DNA to uncoil and express certain proteins that cause the excess dopamine levels to drop. All the way back in the 1950s, psychiatrist Dr. Abram Hoffer proved with double-blind placebo controlled studies showing that niacin could cure many cases of schizophrenia.
Many of you readers may have tried a popular supplement for depression called SAMe, which is known to increase the activity of the mood enhancing neurotransmitter serotonin. It does this by compacting the DNA and inhibiting the expression of genes that code for certain proteins that whisk away serotonin, leaving more serotonin around to help us feel better.
A key point to all this is to appreciate that our bookmarks don’t necessarily determine our destiny without outside influence. The potential to develop a certain disease may reside in our genome, but not manifest unless or until the body is exposed to an external trigger (such as stress, trauma, toxins, inflammation, illness or nutrient deficiencies). This is why certain conditions may suddenly begin or progress after years of being healthy.
Adding to the complex process of gene expression are defects in the DNA code that occur due to one single rung of the DNA ladder being turned around, or switched. These defects are called “single nucleotide polymorphisms,” abbreviated as SNPs and pronounced “snips.” It is estimated that there are around 10 millions SNPs in the human genome, with most of them serving as dividers between genes or not significantly influencing gene function. But some SNPs can have a huge impact on gene expression and health.
As an example, one of the most important enzymes in the body is the one that facilitates methylation of genes, called methyltransferase (MT). Mutations in the genes that code for MT enzymes will impair the proper methylation of DNA and these SNPs can have a huge impact on one’s health.
Another interesting area of SNP testing involves the phase-1 detoxification pathways of the liver, concerning gene mutations that will lead to over or under-metabolization of medications. For many people certain drugs won’t work, need increased doses, or become toxic at typical doses. It seems it should soon be necessary SNP testing prior to prescribing these meds.
The field of epigenetics and SNPs is exploding and we have been testing patients for a number of years, humbly learning how we can influence the expression of their genetic code and improve health. Several drugs, such as DNA methyltransferase inhibitors and histone deacetylase inhibitors, are already used in cancer treatment. New drugs are being sought that can remedy epigenetic defects.
As science uncovers more connections between epigenetics and disease, I expect this will prove to be one of the most important areas in all of medicine. And it is not just an area for pharmaceutical companies to capitalize upon, as we already know of many natural substances, even foods that can improve our epigenetic bookmarks and overcome SNPs. Soon, we just might not be able to simply “blame it on our genes.”
Scott Rollins, MD, is Board Certified with the American Board of Family Practice and the American Board of Anti-Aging and Regenerative Medicine. He specializes in bioidentical hormone replacement for men and women, thyroid and adrenal disorders, fibromyalgia and other complex medical conditions. He is founder and medical director of the Integrative Medicine Center of Western Colorado (www.imcwc.com) and Bellezza Laser Aesthetics (www.bellezzalaser.com). Call (970) 245-6911 for an appointment or more information.