Meeting Minutes
Torch Club of the Fox Valley
14 March 2019
Atlas Coffee Mill & Café
Notes taken by: Mary Flanagan
Attendees: Karen Bachhuber, Sue Bennett, Nancy Bodway, Brian Bushaw, Mary Flanagan, Paul Freiberg, Jean Hedges, Walt Hedges, Jean Jepson, Barbara Kelly, Bill Kelly, Jude Kuenn, Richard Schoenbohm, Katie Shaw, Bob Swain, Peter Thiel, Scott Valitchka, Donna Weis
BUSINESS MEETING
Paul called the meeting called to order at 6:34 pm.
1. Paul and all members offered condolences to Peter for the loss of Helen. Barb will work with Peter to choose books to donate to the Appleton Library as a memorial to Helen from the club. Richard moved that $75 be approved for this memorial to honor the joy Helen brought to the world. Motion was seconded and unanimously approved.
2. Acceptance of meeting minutes from 1/10/2019 was motioned, seconded, and approved.
3. Treasurer’s report: Barb reported that as of 3/7/2019 we have $2758.88 in the account after reimbursing Walt $23.10 for a nametag. The report was motioned, seconded, and approved.
Unfinished business:
1. Presentations: Scott will give the April presentation on “The Geology & Ecology of the Hagar Mountain State Natural Area.” Paul will forward a summary and a brief pre-read from the introduction to geologist and author Marcia Bjornerud’s text Reading the Rocks with the April meeting reminder. Brian will give the May presentation.
2. Richard gave the officer nominating committee’s report. The committee (Richard and Peter) solicited nominations directly from all members and submitted the following nominations: President – Paul Freiberg, Vice President – Bill Kelly, Secretary – Mary Flanagan, and Treasurer – Barbara Kelly. All were elected by a voice vote. The two-year term starts in May.
3. Barb reminded everyone who hasn’t done so to send pictures and bios to her for our website. See http://www.torchfoxvalley.org/ for examples.
New business:
Sue Bogenschutz joined us. She has been having troubling negotiations with the landlord and Atlas will probably no longer be in operation after the end of the month. The boutique and art gallery are closing on March 24. She invited everyone to come March 18 through 23 for customer appreciation week.
Paul thanked Sue for our last supper at the Atlas.
Several possible new venues were suggested. The officers will pursue these and others to find a location for our meeting on April 11 and going forward.
The business meeting adjourned at 7:10 pm.
PRESENTATION
At 7:59 PM Sue Bennett presented:
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EPIGENETIC TRANSGENERATIONAL INHERITANCE
We all are aware of how our genes are passed down from generation to generation. Our DNA, right? That’s why our children look like us. That is genetics or what we think of as nature; something we have no control over. And then there is nurture. All of the things in our environment that we are exposed to from the time of conception that make us the individuals we are. It was believed that those changes affect only us. However, the study of epigenetics is continuing to prove that that is not the case.
Epigenetics is the study of changes in organisms caused by modification of gene expression rather than alteration of the genetic code itself. This is how our cells know to become specialized cells, such as skin cells, liver cells, blood cells, brain cells, etc. They are all very different cells, but contain the same DNA.
Epigenetic inheritance is when genetic information is passed from one generation to the next that affects the traits of the offspring without changing the basic structure of their DNA. The science of epigenetics is giving us new insight into the mystery of just how our environment and experiences impact not only us, but future generations.
The theory of epigenetic inheritance was popularized by Swedish preventative health specialist, Lars Bygren, who in the 1980’s began studying the long term effects of diet on future generations of offspring. In the late 1400’s Bygren’s ancestral family had settled in the small, isolated village of Overkalix, which is located in the northernmost region of Sweden in the late 1400’s. Because of the remoteness of Overkalix, the villagers were very dependent on their crops of grain in order to feed their livestock. There were no stores to buy feed or food from and the growing seasons were short. Consequently, the success or failure of their crops was very unpredictable. Most years were average, but there were also years when the harvest was so bountiful that the inhabitants were able gorge themselves only to have the next year’s harvest fail, resulting in starvation. So the people of Overkalix lived with the uncertainty of
knowing whether they would be living with feast or famine from one year to the next. This turned out to be a great opportunity for Bygren to find out what effect this sudden change in food supply had on the people of Overkalix.
Fortunately for Bygren, the village officials and clergy of Overkalix kept meticulous records of births, deaths and family lineages, as well as details of each year’s harvest. So when Bygren began to study the effect that sudden change in food supply had on future generations, he was able to utilize these historical records. He was able to use in his study the history of 303 men and women born in the years 1890, 1905 and 1920 and their 1,818 children and grandchildren; 44 of which were still alive in 1995.
By using a random sample of almost 100 people born in Overkalix in 1905, Bygren was able to trace their parents and grandparents back to birth. Because of the detailed agricultural records, Bygren, with the help of two colleagues, was able to determine the quantity of food that had been available to those parents and grandparents during their childhoods. It seemed that the age of the parent or grandparent during these times of feast or famine was pivotal. The 1905 children of Overkalix most affected were those who had not yet reached puberty, (9-12 y/o for boys and 8-10 y/o for girls).
Bygren’s research found that of the 1905 birth cohort, the grandsons of the Overkalix boys who had lived on a starvation diet during pre-puberty; that is the time when their sperm cells were maturing, lived an average of six years longer than the grandsons of the boys who experienced gluttony during this same prepubescent time frame. The cause of early death in the well-fed grandsons was often of diabetes.
It was also observed that the food supply of the grandfather influenced only the mortality rate of the grandson and not the mortality rate of the granddaughter. The granddaughter’s risk of cardiovascular disease, however, doubled if her paternal grandmother had been exposed to drastic change in her early life from conception to age 13.
At this point Bygren felt he had evidence that changes in gene expression brought about by the environment of the grandparents was somehow passed down to their progeny by fathers through the environment during the formation of their sperm and mothers through the environment at the times of their conception and pregnancies.
Bygren and his colleagues had the evidence, but could not explain how the children and grandchildren could be affected by what their parents and grandparents experienced as children.
It appears the answer is beyond the bounds of both nature and nurture. Over the past 20 years Bygren’s data and that of many other scientists has given rise to this the new science of epigenetics, which literally means “above the gene.” The epigenome sits above or outside of the genome. These genetic marks signal the genes to turn on or off, or to express themselves more loudly or more quietly. It is because of these genetic marks that external factors such as diet, stress and prenatal nutrition can alter gene expression that is passed to subsequent generations.
In other words, it is not simply that children share their parents’ combined DNA and everything else is new and strictly dictated by their own environmental experiences as was once thought. It has now been proven that changes in the parents’ genetic marks, as a result of their experiences, may also become a part of their child’s epigenetic makeup.
Another study that bears this out is the Dutch Hunger Winter Study. In September 1944, when Nazis blocked food supplies to the Netherlands, more than 20,000 Dutch died of starvation before being liberated in May of 1945. Because this famine had a specific timeline, it has served as an experiment in human growth and continues to be studied today. The lack of nutrition during the famine had a profound lifelong impact on pregnant women and the children they gave birth to during the famine. As a result of the lack of adequate nutrition during their development, when these babies became adults they weighed more than average; in middle age they tended to have elevated triglycerides and cholesterol in addition to higher rates of diabetes, obesity and schizophrenia.
When the death records of hundreds of thousands of Dutch people born in the mid-1940’s were reviewed, it was found that the Dutch Hunger Cohort – people who had been in utero during the famine- died at a higher rate that those born before or afterward.
One partial explanation for how our body is able to remember the environment it was exposed in the womb, according to studies done by geneticist, Dr. Bas Heijmans, epidemiologist, Dr. L.H. Lumey, and their colleagues, is that the famine caused certain genes to be silenced in the unborn children and that they have remained quiet ever since. They go on to explain, as I mentioned earlier, that all the cells in the body have the same genes, but some genes are either activated or silent in different cells. This is why all of our cells have the same genes even though some cells are instructed to be skin cells, liver cells, brain cells, etc. These particular genes are wrapped up tightly and are less susceptible to change and that program is set in place before birth.
So, what exactly causes this gene activation or deactivation? Researchers have identified molecules that cells use to program DNA. One of the most studied programming molecules is the molecular cap called a methyl group. These methyl groups may be present at a million spots across our DNA and because silenced genes often have methyl groups nearby, it is believed that the methyl groups play a role in silencing or activating genes. Some examples of foods that facilitate the methylation of genes are foods that are high in folate and B vitamins such as cruciferous vegetables, salmon, liver, pumpkin seeds and brown rice.
Because researchers now have the ability to detect methyl groups at nearly 350,000 spots on the genome, Drs. Heijmans and Lumey were able to search for methyl groups that were common in the Dutch Hunger Cohort. What they found was that some methyl groups were linked to both the famine and health conditions later in life. Dr. Lumey proposed that methyl groups disrupt how cells normally use genes. For instance, one methyl group that is linked to a higher body mass index may have quieted a gene that is involved in burning the body’s fuel and continued to do so for life, possibly adjusting the body’s metabolism to function in a lower gear. This adjustment in the body’s fuel requirement may have allowed for people to survive on a smaller number of calories. Think of it as turning down the thermostat on a furnace in order to conserve energy.
At this point not all scientists have completely accepted this explanation. Some believe that the babies who did survive the Dutch Famine may have been the result of some genetic variant that made them more resilient. However, Dr. Heijmans studied the same methyl groups in muscle cells, fat cells and other tissue groups and found that the pattern was basically the same.
Dr. Heijmans also stated, however, that these findings would need to be followed up with carefully controlled experiments on animals that can provide more information on how a prepubescent father or a gestational mother’s food supply affects the epigenetics of their offspring. Some of this hard evidence for these epigenetic changes across generations so far has come from studies of roundworms and rodents.
One example is the results of a Duke University study, done by Ryan Baugh, on a worm species called C. elegans, which is a millimeter-long roundworm that is widely used as a model for larger organisms. This study showed that if the mother worms are underfed, their offspring grew at a slower rate, ended up smaller and less fertile, but were also more resistant to starvation.
Another study utilizing the roundworm was performed by NASA in 2015 at the International Space Station to investigate whether adaptations to microgravity transmit from one cell generation to another without changing the basic DNA of the organism. If epigenetic changes occur in response to microgravity and it leads decreases in muscle and metabolism in the space-flown roundworm, it strongly suggests that similar epigenetic changes probably occur in humans. This may partially explain why muscle development responses to exercise training are reduced, and why astronauts have difficulty maintaining muscle and bone mass during spaceflight.
These experiences can also cause a change in behavior as well. In his Montreal laboratory, Dr. Michael Meaney carried out experiments in which two identical strains of rats were separated into two adopted groups, a caring group where babies are licked and groomed regularly and a colder group with low licking and grooming behavior. The result is that while the more cared-for rats showed lower levels of stress, the less cared-for rats suffered epigenetic changes to the genes that affected the levels of the stress hormone cortisol, causing this group to react more negatively and antisocially. They also found that the effect was still detected over three generations. The good news was that the harmful effects could be partly reversed by putting the second generation of pups with “caring” foster mothers. These results may also have some bearing on why the survivors’ children and grandchildren of the Dutch Famine had higher rates of schizophrenia.
Yet another study using mice was with regard to agouti characteristics. Agouti is a gene that controls the distribution of the natural pigment melanin in the hair of mammals and helps determine their coat color patterns. The mouse with the agouti gene has a light yellow coat and is obese. When researchers fed the pregnant Agouti mouse a methyl rich diet, her offspring had a brown coat and normal weight. These offspring who were nourished with the methyl supplement in utero in turn gave birth to brown, normal weight babies in spite of not being fed the methyl rich diet themselves. So what the mother ate during the gestational period affected not only her offspring, but her offspring’s offspring.
Epigenetic inheritance is a relatively new and exciting science and what has been learned thus far is only the tip of the iceberg. The study of epigenetics has the potential to solve the mysteries of the principles and mechanisms for human disease, diagnosis and therapy. If we can discover the biology of these changes, and how to use that knowledge in a positive way, it could have an impact on the health, happiness and well-being of future generations.
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Sue noted that the current issue of The Torch magazine contains an article on epigenetics. She also recommended The Emperor of All Maladies: A Biography of Cancer by Siddhartha Mukherjee and the Ken Burns documentary by the same name.
Meeting adjourned at 8:30.