When I learned about DNA in high school, we were told that was it. Our DNA explained who we were. It was written in the double helix inherited from our ancestors. Yes, DNA was the ultimate winner in the smackdown battle between nature versus nurture, that is, until epigenetics came along.
What is epigenetics? The International Waldenstrom’s Macroglobulinemia Foundation explains:
Derived from the Greek, the word epigenetics literally means “above” genetics. Epigenetics is the study of chemical markers that modify genes but are not part of DNA itself. Like DNA, they can be passed on from cell to cell and from one generation to the next. These modifications are superimposed on top of our genes to tell them whether they should be active or inactive. For example, every cell in your body has the same DNA; however, some cells are specialized for use in the heart, the bones, the brain, the nerves, the stomach, etc. These cells become specialized because different sets of genes are turned on or off at different points in cell development, leading to differences in the types and amounts of proteins produced and determining how the cells look, grow, and act. This is epigenetics in action…
Just as we know that our DNA can change because of mutations, our epigenetics can also change during our lifetime. Lifestyle and environmental factors can expose us to chemicals that change our epigenetic profile. In other words, what we eat and drink, whether we smoke, what medicines we take, what pollutants we encounter, how quickly we age, may affect this process. Look at the case of identical twins. Although they share the same DNA, their bodies may not be exactly identical. One twin may develop arthritis or diabetes, for instance. At least some of these differences are due to changes in our environment that affect our epigenetics.
Research has shown that shortages or excesses of food during a person’s childhood can cause epigenetic changes that lead to diabetes, obesity, and early puberty. Genes become epigenetically modified to deal with adverse conditions and then pass on to offspring who may enjoy more comfortable conditions. Changes that made sense during a time of hunger can then transfer to children and grandchildren who live in a time of abundance.
Meet the Epigenome
The answer lies beyond both nature and nurture. Bygren’s data — along with those of many other scientists working separately over the past 20 years — have given birth to a new science called epigenetics. At its most basic, epigenetics is the study of changes in gene activity that do not involve alterations to the genetic code but still get passed down to at least one successive generation. These patterns of gene expression are governed by the cellular material — the epigenome — that sits on top of the genome, just outside it (hence the prefix epi-, which means above). It is these epigenetic “marks” that tell your genes to switch on or off, to speak loudly or whisper. It is through epigenetic marks that environmental factors like diet, stress and prenatal nutrition can make an imprint on genes that is passed from one generation to the next.
I first learned about epigenetics last year when attending a conference on Teaching Children with Developmental Disabilities to Speak. The following three points were made about the importance of epigenetics, neurology and chemical avoidance:
- Avoid BPA!: Our genes are most vulnerable during pregnancy and adolescent. Chemicals in our environment affect our genes (epigenetics).
- Parenting and nurturing affects genes: Here’s the scientific proof attachment parenting is important. Behavioral cues are also part of epigenetics (“environmental factors that change genes in the first and second generation”). Babies need to be held and talked to closely to caregivers.
- “The best diet for pregnancy is organic!”: Epigenetics again! Maternal diet has a great effect on the developing brain.
In a recent vaccine debate spurred by the tragic death of a child after receiving the flu vaccine, I was reminded of the importance of epigenetics. I think epigenetics is the reason some children have adverse reactions to vaccines, whether they develop autism or not, die or not, or develop other serious injuries. Let’s be clear…vaccines are full of chemicals, and we are injecting them right into our little ones bodies.
Is there a link between epigenetics, vaccines, and autism? It may be the only answer…
Age of Autism thinks so:
The epigenome is then best understood as existing above your genes (or genome), but influencing how your genes work. The explanation offered by biologists is that if your genome can be compared to a computer’s hardware, the epigenome is the software telling it how to function. The process of changing the genome is through a process called DNA methylation; a single carbon atom attached to three hydrogen atoms. “When a methyl group attaches to a specific spot on a gene . . . it can change the gene’s expression, turning it off or on, dampening it or making it louder.”
All of which brings us back to autism.
Our community has long asserted our children were not genetically pre-determined to get autism. If autism was purely a genetic problem then the numbers should be 1 in 100 from here until the dawn of time. The autistic should be part of our culture, the stories we tell, the very fabric of our society. But they’re not. Instead we have stories about the tidal wave of adults with autism we can expect in the next few years and how poorly prepared we are for them. Nobody saw this problem until it was first described in the 1940s. From that time it’s gone from 1 in 10,000 to 1 in 100. With that rate of increase, can it be long until it goes to 1 in 10? We need to find answers.
And let’s be clear about it. Most of us saw a change after a vaccination, a procedure which has become more common since our generation (10 vaccinations in the 1980’s before the age of 5 to 36 vaccinations under the current schedule) and has been administered at earlier ages.
Many of the far-sighted researchers and physicians in autism have been talking about DNA methylation for years. These concerns have finally begun to enter the mainstream conversation.
Scientists have discovered environmental toxins that even your grandparents were exposed to could affect the children being born today. Here’s an example. Scientists exposed lab animals to a particular pesticide. Expectantly they exhibited neurological damage and autistic like behaviors. Here’s the catch – they compared the animals hard genes before and after exposure and determined they were undamaged. They then bred the animals… Surprisingly four generations later the great great siblings exhibited the same percentage of autistic like behavior and neurological damage – even though they were never directly exposed to pesticides and it would not be found in their blood stream. Scientists have discovered that our epigenetic systems to be so much more susceptible to minute amounts of toxins like pesticides and worse yet the epigenetic mutaltions can be passed down through the generations making the causal relationship or “evidence of harm” so elusive.
Whether it is generational exposure to pesticides and/or vaccines, something is going on here. The MMR vaccine was developed in the 1963. In two to three generations, could this vaccine be causing the increase in autism?
More recently, however, researchers have begun to realize that epigenetics could also help explain certain scientific mysteries that traditional genetics never could: for instance, why one member of a pair of identical twins can develop bipolar disorder or asthma even though the other is fine. Or why autism strikes boys four times as often as girls…
Can epigenetic changes be permanent? Possibly, but it’s important to remember that epigenetics isn’t evolution. It doesn’t change DNA. Epigenetic changes represent a biological response to an environmental stressor. That response can be inherited through many generations via epigenetic marks, but if you remove the environmental pressure, the epigenetic marks will eventually fade, and the DNA code will — over time — begin to revert to its original programming. That’s the current thinking, anyway: that only natural selection causes permanent genetic change.
Scientific American concurs:
Given the elusive nature of inherited epigenetic modifications, it seems that, despite decades of investigation, scientists remain on the brink of understanding. The possibilities, however, seem endless, even with the constraint that, to be inherited, epigenetic modifications must affect gene expression in the germline, a feat that even genetic mutations rarely accomplish. But with the skyrocketing prevalence of conditions such as obesity, diabetes, and autism, which have no clear genetic etiology in the majority of cases, as Brunet pointed out, “It seems that all complex processes are affected by epigenetics.”
While scientists continue to search for definitive evidence of transgenerational epigenetic inheritance in humans, the implications so far suggest that are our lifestyles and what we eat, drink, and breathe may directly affect the genetic health of our progeny.
I would add what we inject into our bodies to that list of lifestyle implications.
We know vaccines cause injuries, otherwise there wouldn’t be a compensation program, even though it rarely pays out. A New Jersey family did, however, get $4.7 million from this program. The same holds true to the safety of pesticides that once are considered safe, only later to be considered harmful, such as DDT.
The Lancet study linking autism and vaccines may have been flawed and thus retracted, it did not examine vaccines and epigenetics. It does not end the controversy. It does not disprove the link.
The combination of vaccines and other environmental toxins on epigenetics is the most reasonable cause for the rise of autism. It does not take vaccines off the hook, as many assumed by the Lancet retraction did. It doesn’t mean that vaccines don’t save lives. It means we need to clean up the chemically-ladened world our children live in, both in medicine and in the home.