I ordinarily don’t like to report on animal studies largely because my blood boils over when I hear of the unspeakable things that scientists do to animals in the name of research. And of course all that slicing and dicing is oftentimes done for no good reason because you cannot always apply the results to human beings.
But I’m going to tell you about several little mice studies because if their results are shown to have a parallel application to human beings, they upend just about everything that orthodox scientists say about our biology.
DNA – the master switch?
The most favored idea about human mind and body is that there exists a genetic ‘program’ of genes operating collectively to determine our health and longevity. In this view, DNA holds the master switch to selectively turn off and on certain genes and choose certain RNA molecules, which in turn select from a large alphabet of amino acids the genetic ‘words’ that create specific proteins, which ultimately control every bodily function, including intelligence and every aspect of health, including longevity.
In the simplest terms, according to this view, genetics is destiny.
Epigeneticists like my dear friend Bruce Lipton argue against this view that we are virtually programmed by our genes, with new evidence that the master builder of living things is not a cell’s genetic programming; our cells, our gene expression and therefore our entire organism is largely shaped by environmental influences.
As you probably know, scientists know how to manipulate genes, so that certain ones can be turned on or off (or ‘knocked out’, as they indelicately put it). Recently a researcher called Li-Huei Tsai with a team from Howard Hughes Medical Institute at Massachusetts Institute of Technology selectively bred a group of mice with something akin to Alzheimer’s disease — the presence of a certain protein that causes degeneration of neurons in the brain.
Animals like this have profoundly impaired learning and memory, and impaired long-term potentiation (LTP), a crucial cellular process in memory. In very short order, after signs of brain atrophy and loss of neurons, these mice become demented.
Up until now, scientists have believed this genetic coding to be firmly fixed, operating through a cascade of processes – of proteins affecting other proteins and then amino acids, like a game of dominoes – which ultimately lead to switching on (or not) of connections between neurons.
In the study, Tsai subjected the mice to two tasks, both designed to test memory and ability to learn. The first was to study whether they were capable of ‘fear conditioning’ – where the animals would have to undergo a task that ordinarily would cause them to associate going into a specific chamber with receiving a mild electric shock. In the second test, the mice had to find a submerged platform in a tank of murky water.
Ordinarily, a fear-conditioning situation produces a long-term memory of the event; once we burn our hands on the stove, we know forever after to steer clear of a gas flame. Nevertheless, this group of mice failed both tests; their brains appeared to have atrophied to the point where they could not learn from an unpleasant experience or indeed anything, like their murky water test, requiring memory storage.
Impressed by studies showing that an ‘enriched environment’ can improve learning capability, Tsai wanted to test whether the same was the case in an animal who’d already suffered brain degeneration.
This time, she placed her mice population in an action-packed environment, containing new mice, an exercise treadmill, and a variety of bright and different shaped and textured toys, which were changed every day.
To their amazement, once the researchers again tested the animals with the tasks, the mice who’d been stimulated showed marked improvement over animals without the additional stimulation.
When Tsai and her colleagues studied the brains of these animals after their deaths, she discovered that this environmental stimulation actually had altered a part of cellular proteins and chemical tags, which finally turns on or off certain genes.
The environment overrode the genetic blueprint. Genes were not destiny.
A recent study carried out by Larry Feig and his research team from Sackler School of biomedical Sciences at Tufts University extended this idea – to see whether an educational environment could override genes in very young mice with certain major neural handicaps.
This time, Feig and his team they’d knocked out the Ras-GRF genes in a group of baby mice. Without this gene, a mouse again has cellular processing critical for memory and learning, and poor synaptic efficiency in the brain, leading to poor information storage.
Mice without this gene again cannot learn fear. Put them in a potentially unpleasant situation they’ve already experienced, provide the stimulus that should set off a memory of the event, and they won’t have the foggiest memory of it.
This time, the researchers exposed the 15-day-old mice to the equivalent of a indoor theme park designed for novel stimulation: a large cage with play tubes, cardboard boxes, a running wheel, and both toys and nesting material that were all changed or rearranged every other day.
Compensation in the brain
After two weeks, Feig discovered that in this enriched environment, the mice developed a compensatory brain switch, which switched on new pathway that works with with Ras-GRF proteins to help in long-term memory and learning. Even though they had this gene ‘knocked out’, a stimulating environment in a sense turned it back on. The mice showed evidence of normal memory and fear conditioning.
Feig then took this one stage further and examined what happened to their offspring – even though they were given a normal environment, rather than a theme park.
Astonishingly, the offspring of these mice showed evidence of normal memory and learning ability – even though they themselves had had no additional stimulation and should have inherited the turned-off gene.
The environmental effect of their ancestors again overrode their genetic destiny.
If they can be applied to humans (always a big if), the implications of these studies are just extraordinary (and not surprisingly have gained the attention of organizations working with Alzheimer’s disease).
Stimulation and connection
They suggest that connection between a living thing and its world, in the form of social interaction and a constantly stimulating and renewing environment, can be the most potent healer - even of brain damage or genetic birth ‘defect’.
This is supported by enormous evidence of human centenarians showing that those who lived longest had two important aspects: a strong connection, socially and spiritually, and a continued curiosity about the new.
The studies also suggest the most radical idea of all: a mother’s environmental influences will influence the genetic expression of her children. If her environment was constantly stimulating and social, then this will have a bigger effect on her children than their genetic heritage.
It may well be that you are what your grandmother played with.
This sounds to me suspiciously like a Field effect.