Did you know that Tales is also an education platform that aims at spreading knowledge far and wide? Well I am non-commercial and I is educational. It’s true and if I state this I can post the whole article. I hope.
This is important knowledge. Everything we do, even our thoughts, affects our descendants forever. Yikes!
A growing body of research is revealing associations between birth defects and a father’s age, alcohol use and environmental factors, say researchers at Georgetown University Medical Center. They say these defects result from epigenetic alterations that can potentially affect multiple generations.
The study, published in the American Journal of Stem Cells, suggest both parents contribute to the health status of their offspring—a common sense conclusion which science is only now beginning to demonstrate, says the study’s senior investigator, Joanna Kitlinska, PhD, an associate professor in biochemistry, and molecular and cellular biology.
“We know the nutritional, hormonal and psychological environment provided by the mother permanently alters organ structure, cellular response and gene expression in her offspring,” she says.
“But our study shows the same thing to be true with fathers—his lifestyle, and how old he is, can be reflected in molecules that control gene function,” she says. “In this way, a father can affect not only his immediate offspring, but future generations as well.”
For example, a newborn can be diagnosed with fetal alcohol spectrum disorder (FASD), even though the mother has never consumed alcohol, Kitlinska says. “Up to 75 percent of children with FASD have biological fathers who are alcoholics, suggesting that preconceptual paternal alcohol consumption negatively impacts their offspring.”
The report is a review of evidence, human and animal, published to date on the link between fathers and heritable epigenetic programming.
Among the studies reviewed are ones that find:
Advanced age of a father is correlated with elevated rates of schizophrenia, autism, and birth defects in his children;
A limited diet during a father’s pre-adolescence has been linked to reduced risk of cardiovascular death in his children and grandchildren;
Paternal obesity is linked to enlarged fat cells, changes in metabolic regulation, diabetes, obesity and development of brain cancer;
Psychosocial stress on the father is linked to defective behavioral traits in his offspring; and
Paternal alcohol use leads to decreased newborn birth weight, marked reduction in overall brain size and impaired cognitive function.
“This new field of inherited paternal epigenetics needs to be organized into clinically applicable recommendations and lifestyle alternations,” Kitlinska says. “And to really understand the epigenetic influences of a child, we need to study the interplay between maternal and paternal effects, as opposed to considering each in isolation.”
Everyone says you are what you eat, but, for some reason, the majority of the world’s population seems completely oblivious to this fact. Yet pure science and simple experiments have managed to definitively prove what naturopaths have been saying for centuries: What you eat changes you, down to your very DNA. As it turns out, our diet can influence what genes are more active or suppressed. Basically, it can determine whether genes associated with conditions like obesity, type 2 diabetes or heart disease are hyperactive or functioning within parameters.
It’s particularly easy to ignore that our diets directly affect our health when the foods around us taste so good. General practitioners who don’t take food into consideration when treating their patients certainly don’t make it any easier. In this context, new studies that point to the relevance of food in connection to our DNA are an essential step forward.
We don’t even know the half of it
The nutrients that the human body receives in utero, as well as the ones it feeds on after being born, invariably affect our genes. The prevalent opinion is that our genes determine how nutrients are broken down and then absorbed by cells. Scientists thought that all information other than the pure genome is deleted when a new embryo is formed. However, in 2013, when the human DNA was completely mapped, a lot of variables were still missing. This much was clear because the genome on its own could not explain all of the physiological processes we are currently familiar with.
Obviously, more things were going on with our genome than we were able to see. Until now, the separate field of epigenetics was associated with the changes that our DNA undergoes as a result of outside forces, i.e. our diet or the environment we live in. The separation of the fields was necessary because scientists thought that the genome itself does not change – only its surroundings do. Now, evidence shows that the characteristics of these surroundings, chemicals and enzymes, can irrevocably affect our bodies as they develop.
For instance, in mice, the risk for chronic diseases and radical differences in weight and metabolism are greatly affected by the mother’s diet during pregnancy. A study conducted in 2006 concluded that, even if the mother is obese and has an increased chance of developing certain diseases, such as diabetes or cancer, the majority of her offspring are born healthy and with normal health risks, provided that her nutrition is appropriate during gestation. Thus, almost no disposition for chronic diseases or body constitution was inherited as a result of her DNA but rather as a result of eating habits during pregnancy. In human beings, a well-balanced diet has a definitive impact upon our genetic disposition to certain diseases.
The domino effect
Recent studies have proven that an unbalanced diet has a domino-like effect upon the health of the entire organism. In order to maintain ourselves as disease-free as possible, it’s imperative that we have a diet with equal intakes of carbohydrates, protein and fat, according to researchers from the Norwegian University of Science and Technology. When either of these categories dominates over the other, the nutrients we get from food become the prevalent chemicals our DNA has in its surroundings. A good example is that of a diet that contains 60% or more carbs. Lab research has found that, in these circumstances, the genes associated with cardiovascular diseases and diabetes start to speed up their processes.
Sometimes, the changes that occur as a result of eating habits are simply astounding. Dr. Markus Ralser, a biochemist from the University of Cambridge, indicates that almost all of a cell’s genes are directly influenced by the nutrients it has access to. All it takes is for a few substances to go missing, and the regular metabolic profile becomes altered in a significant way. Although researchers have yet to exactly pinpoint which food does what, experienced nutritionists have formed a few hypotheses based on the amount of nutrients each food item has.
It’s never been this obvious that current medical practice has a lot to integrate in the fields of nutrition and genetics. Until things change for the better, it’s up to the people who stay informed to take action and ensure that their health, along with that of their families, is headed in the right direction.
Senior Research Fellow, Dept of Sociological Studies, University of Sheffield
March 15, 2016
Epigenetics, the study of how environmental factors and lifestyle choices influence our genes, has flourished to become one of the most groundbreaking areas of science over the past decade. Studies have shown that, among other things, toxins, stress, socio-economic status, bullying, racism and the lifestyles of our parents and grandparents can all turn on or off certain genes in our DNA. The field is radically changing how we think about nature and nurture – giving it an impact far beyond the lab.
But what are the wider implications now we no longer seem to be just a product of our genes? If it is possible to improve the functioning of everyone’s genes with the right environment, it may seem that a better understanding of epigenetics will lead to a more liberal and egalitarian society. But in my recent book, Political Biology, I note some worrying signs that the opposite could also be true.
Despite big research efforts, there are still uncertainties about the exact nature of epigenetic effects. This is especially true when it involves claims that changes to genes persist for generations. For that reason, epigenetics remains a controversial science, although progress is being made rapidly.
However, despite these uncertainties, the wider implications are often taken for granted. Epigenetics is generally considered to be a basis for a better, more progressive, liberal and inclusive social policy. If the environment is much more important than we thought in shaping our fate, there seems to be much more space to attack inequality at its root. In fact, this has been a popular argument, used by people including Nobel Laureate James Heckman.
A eugenic legacy?
But is that the whole truth? To understand the darker implications of epigenetics, just think back through human history. There certainly is no shortage of war, famine, exploitation, destruction, epidemic and trauma. Knowing that some of this can leave a biological trace in our genes – which can even be transmitted to future generations – could be problematic.
Even in the 1920s, some believed that the environment could influence inheritance. Some focused on the fact that we could inherit the best of our civilisation and become better humans, while others argued that certain populations had been exposed to various pathogenic environments (alcoholism, poverty, promiscuity, hot climate) for too log, becoming irreparably damaged. Their offspring, too, had to be treated with special care, as it was believed that the damage was likely transmitted across generations.
The latter idea in particular played into the hands of supporters of eugenics, a popular theory in the early 20th century. It was based on the belief that the quality of the human population could be improved if people with traits seen as undesirable could be stopped from reproducing. Some countries therefore launched eugenics programmes prohibiting certain marriages and supporting forced sterilisations. Those seen as unfit to pass on their genes typically included people with mental or physical disabilities. However, such measures became increasingly out of fashion after World War II (though persisted until 1970s in many Western countries), as it became associated with Nazi Germany (in truth Nazis learned a good deal from American eugenics).
Around 1910, English physician, writer and maverick supporter of eugenics, Caleb Saleeby, for example, spoke about “racial poison” to describe the destructive effects toxins such as alcohol could have on entire populations (“race”). The implication was that some races, or social groups, had an acquired inferiority to others.
But then genetics became the new norm – and the idea of a heredity that could be poisoned by environmental factors pretty much disappeared from Western policy debates. For a while, it was believed that genes make us who we are, not what happens to us or our ancestors.
Then epigenetics – which came to the fore around the year 2000 – changed everything again. In 2013, The Economist titled a story about an epigenetic study on folate deficiency “Poisoned inheritance”. While the magazine was likely unaware of the past use of the term, it was a telling moment for us sociologists.
Meanwhile, in 2009, a well cited study in the American Journal of Human Biology linked the relatively low birth weight of African-Americans, compared with European-Americans, to the long-term effects of 19th century slavery. The study noted that low birth weight leads to higher mortality in infancy and long-term negative health consequences. It highlighted epigenetic mechanisms as a potential factor influencing such long-term effects. Such a speculative claim is obviously open to a large number of different interpretations. It can support arguments for a better and stronger investment in the healthcare system – but, far more worringly, it can also be used by racist groups trying to argue for the “acquired inferiority” of specific populations.
Similarly, a study on social inequalities in Glasgow found that the poorest people, as well as the manual workers, were born with low levels of an epigenetic marker called DNA methylation (a biochemical process that controls how genes work). Lower methylation has been related to the risk of developing diabetes and cardiovascular disease, and linked to the stressful conditions experienced by expectant mothers in poor areas.
The Irish Times spoke of “cards of life … dealt just weeks after conception, when methylation takes place in the embryo”. Similarly, The Scotsman declared: “Babies born into poverty are damaged forever before birth.” It is clear that these findings could be used not only to call for regeneration and support, but also to talk about degeneration and “poisoning”.
Today, we generally are educated about the dangers of eugenics. But it is important to keep talking about these issues, before minority groups such as racists try to hijack epigenetics to further their cause. In focusing on the environment as a cause for many unwanted conditions, epigenetics has the potential to advance social justice. But we need to remember that it is no guarantee of a more inclusive society. Social values often decide how we implement science, rather than the other way round.
Lecturer/Senior Lecturer, Nottingham Trent University
March 15, 2016
The Dutch famine of 1944 was a terrible time for many in the Netherlands – with around 4.5m people affected and reliant on soup kitchens after food supplies were stopped from getting into the area by German blockades. As many as 22,000 people were thought to have died, and those who survived would find it extremely difficult to ever fully recover.
The dietary intake of people in affected areas was reduced from a healthy 2000 calories a day to a measly 580 – a quarter of the “normal” food intake. Unsurprisingly, without a balanced diet, children born to mothers who were pregnant during the famine showed a much lower than average birth weight.
But then something strange happened: their children’s children had the same low birth weight, despite their mother’s “normal” food and calorie intake.
We often talk about our genetic make-up and “how good” or “how healthy” our genes are. We also know “bad genes” can lead to us having a higher chance of developing a particular disease if our parents are carriers. But while scientists can look for those faulty or changed genes, over the last decade we have learned this is not the whole story.
Because it is not just our genes and DNA which determines our health, but also environmental factors such as diet, stresses, and lifestyle choices – just like in the Netherlands.
These environmental conditions, alongside the life experiences of our parents, grandparents, and even our great-grandparents, have been shown to flip “stop” and “go” signals which regulate pretty much every process taking place in our cells. These signals can then cause changes on top of the inherited DNA molecules which can determine our well being – hence the lower birth weight of babies only distantly related to the famine.
Epigenetics takes the age-old question of “nature vs nurture” to a whole new level of scientific interest. But it is a controversial field of study with wide-reaching implications which could change everything we thought we knew about genetic inheritance.
What we do know, though, is that the environment and our nutritional intake plays a crucial role in affecting changes to our DNA – which has been demonstrated by the effects of the Dutch famine. The famine has shown how changes in epigenetic markers – the “stop” and “go” signals – are inherited, from parent to offspring and to their offspring in turn. This process is called transgenerational inheritance.
The genes affected are ones that are important in processing nutrients and are associated with diseases such as diabetes or are implicated in mental health conditions such as schizophrenia and bipolar disorders.
Studies on identical twins show how the environment and trauma can change these epigenetic flags. While the siblings were genetically identical, their identical epigenetics changed over time – essentially showing how environmental factors can alter genes which are linked to depression, anxiety and obesity.
Recently, studies using mice, rats, fruit flies and worms have also shown that trauma and stress can affect these epigenetic flags which then get passed on to the next generation, and then on to the next.
We know that if a female rat takes good care of her offspring, for example, then the pups are able to cope better with stress compared to rat pups that were ignored and had high levels of stress. In this instance, the removal of “stop” signals on a specific gene seems to be linked to happier offspring.
Similarly, male mice who experience stress early in their lives pass this on, even to their grand pups – which are more likely to show symptoms of anxiety and depression, even if they were looked after well and grew up in a nurturing environment.
Fixing the future?
Studies in humans are difficult to control as generally we do not have a reference value for epigenetic markers before a trauma or stress, so we cannot make easy comparisons. But what we do know is that women who were pregnant while experiencing extremely stressful situations, such as the 9/11 attacks, apparently have passed on this experience to their child.
Their children have reported experiencing depression, anxiety and poor coping mechanisms in stressful situations. Similarly, children and grandchildren of Holocaust victims often have mental health issues.
But it isn’t all doom and gloom. We aren’t simply living at the mercy of our ancestors’ past lives because we do know that at least some of the epigenetic marks are reversible.
We potentially can affect our epigenetics by living a healthy lifestyle and providing our body with the necessary building blocks for these epigenetic flags.
Recent research also shows that drugs can remove negative epigenetic marks and remove “stop” signals – which has been shown to allow changed genes present in cancer, Alzheimer’s or diabetes to go back to their original state.
So while we may still be some way off fully understanding the role epigenetics plays in the “nature vs nurture” debate, one thing is clear: it’s not simply our genes that make us. So next time you’re feeling stressed or angry, or thinking about grabbing another takeaway pizza on the way home, think of your future grandchildren. It may save them a whole lot of bother.