Your Genes Programmed by your Ancestors’ Terror

DNA and memory

One of your ancestors had a terrifying experience? New research shows your genes might have a memory of this terrifying experience built into them, and you may fear the same thing happening to you.

But that’s now how genes should work, is it?

To understand this, we’ll begin by considering identical twins, who are born with identical genes.

Over time, their bodies and behaviors become increasingly different, more so if they grow up in different environments, having different experiences.

What happens to us in life changes the way our genes behave – this is called gene expression. What you do, what you eat, how you exercise, even the music you listen to alters your gene expression.

There’s no doubt that terrifying experiences also change our gene expression. This is accepted science. The behavior of the genes in our bodies changes with our experiences.

In technical terms, your inbuilt, inherited genes, called your genotype, are influenced by gene expression to determine your phenotype. Your phenotype is YOU – the way you develop, and behave, your internal biochemistry, the way you think, and what you do with your time each day.

It’s already well-known that if one family member has a phobia, then the levels of this phobia among first-degree family members will be much higher than average, by a factor of more than x10.

More recently, scientists have claimed that terrifying experiences do not only affect your phenotype, they actually get built into your genes and can be passed on as an inherited fear to your offspring and generations to come.

Barry Dias and Kerry Ressler from Emory University School of Medicine exposed mice to fearful experiences (electric shocks) while there was a smell of cherry blossom around.

We’d normally expect this would alter the mice’s gene expression, affecting their behavior – their phenotype. We would not expect it would fundamentally change their genotype, their basic genetic code that would be passed on to future generations.

BUT it turns out that the mice’s offspring and the offspring’s offspring were still fearful of the scent, even though they had never smelled it before and had no reason to fear it.

The brains of the parent mice were found to have been changed by their experiences, and the offspring also showed the same changes to their brains.

This is evidence that a parent’s experiences can be written into the parent’s genetic code, then passed on to the children and later generations. If an ancestor of yours had a bad experience, you might also fear that experience, even if you have no reason to fear it from your own experiences.

Your own fears, such an unusual terror of spiders, heights, open spaces, or closed spaces, etc, may come from something that happened to a parent, grandparent, or someone further back in your family tree.

This is a rather extraordinary claim, and does not fit with our current understanding of evolution by natural selection.

It’s a basic tenet of science that the more extraordinary the claim, the higher the level of proof that is required. So don’t go expecting that the evidence from this single study will be enough to change the textbooks. More studies will be required for that to happen.

All the same, it’s very interesting, and science does thrive on interesting new phenomena.

Much more speculatively, the research also raises the possibility that other memories of our ancestors could have been built into their genes and passed on to us.

If this were true, claims of people to have memories of previous lives may need to be revisited… but this really is entering the realms of fantasy, isn’t it?


America Losing its Honey Bees – Science to the Rescue?

The White House has become so worried about the collapse in America’s honey bee population that it has established a team to get to grips with the decline. There seems to be a particular problem of too few bees making it through the winter months compared with the past.

Honey Bee
The Honey Bee

The population fall off last winter was an alarming 23% compared with a normal 10% or so. Some recent years have seen one-third of bees dying.

Foods that depend on the humble bee for pollination include honey (obviously), okra, onions, cashews, celery, brazil nuts, beets, canola oil, broccoli, cauliflower, brussels sprouts, turnip, peppers, safflower, chestnuts, watermelons, tangerines, coconuts, coffee, cilantro, hazelnuts, cantaloupe melons, cucumber, pumpkins/zucchini/squashes, lemons, limes, carrots, buckwheat, sunflowers, flax, apples, avocados.

Bees pollinate crops each year worth $15 billion in America alone. Worldwide, the value is about $200 billion. Depending on your diet, somewhere around one in three or one in four of every bite of food you eat depends on the efforts of a worker bee. The NRDC says that California’s $2.5 billion almond industry needs half of America’s honey bees.

A variety of causes are blamed for the decline including: pesticides, diminishing genetic diversity, immuno-deficiencies, and parasitic mites.

Another concern is CCD – colony collapse disorder – where the worker bees in a hive suddenly disappear in large numbers. They don’t die, they just disappear. No dead bodies are found. The cause of CCD is unknown, but may be one of the causes mentioned above.

As we mentioned last week, the population of Monarch Butterflies and many other pollinators are also in severe decline in America.

Environmentalists are blaming a group of pesticide chemicals known as neonicotinoids for the bees’ plight. These chemicals have now been banned by the European Union. The American EPA believes, however, that the parasitic mite varroa is the most likely culprit.

Recent Research Suggests Pesticides and Fungicides are Weakening Bees’ Defenses Against Parasites

Jeffery Pettis and other researchers from the University of Maryland and the Department of Agriculture have identified a toxic combination of fungicides and pesticides which is poisoning the pollen bees eat.

To illustrate the effect, they took pollen from bee colonies on the east coast, which were gathering their pollen from crops treated with fungicides and pesticides. They fed the pollen to healthy bees and found these bees became much more vulnerable to parasitic attack. Each sample of pollen was found to be contaminated with an average of nine different agricultural chemicals.

The White House has now instructed the EPA to develop a strategy before the end of 2014 to combat the decline in pollinating insects.

$8 million of government funding will also go to farmers in northern states to establish new habitats for bees.

If the EPA confirms that pesticides and fungicides are to blame for the bee die-off, will any action be taken? Or will it simply be a matter of money. If it will cost more in pest damage to stop using certain chemicals, will the pollinating insects be sacrificed? Your guess is as good as mine.

Personal Action

If you’d like to take individual action to help honey bees, stopping pesticide and fungicide use looks like a good place to start. Then grow plants that provide bees with good sources of pollen and nectar, such as red clover, foxglove, dandelions, alfalfa, and bee balm.