Embryonic Development
Stem Cells and Epigenetics
““I praise you, for I am fearfully and wonderfully made. Wonderful are your works; my soul knows it very well”. Psalm 139:14
see last week’s post for background - “The Intelligence of the Cell” …today - after warming up with some eye-opening commentary in the latest global warming hysteria, and a severe warning to parents who might be considering letting their children get caught up in this trans-gender nonsense, I shift gears and ask you - how does the embryo know how to start converting stem cells into the specialized cells that are needed for skin , bone, nerves, blood, etc, etc. Without research in epigenetics, we might observe what is happening in the embryo and be amazed by it, but we wouldn’t have a clue as to why or how the drama of scheduled and precisely timed events happen as a baby forms in the womb.
first, where’s the beef?
Climate change hysteria is driving the whole world to insanity. Now that humans are being blamed for warming the world up too much, one of the solutions seldom mentioned out loud is to reduce the population. That’s actually one of the motivations of elites funding the abortion industry. But as if going after human life wasn’t enough, now there’s momentum to go after the meat industry. Ireland, France, Holland, and Denmark are floating ideas of culling the herds of livestock, claiming that eliminating all that methane gas will save the planet. 13 large meat producing countries have pledged to reduce methane production. Denmark is proposing a 33% tax on beef. Reducing ranching and meat production will accomplish two things at once: weakening the economy and our health. Meat is a high-powered source of nutrition.
Beyond Meat
An interesting sidelight on this is what has happened to the artificial (plant-based) meat movement. Apparently it was a fad that is petering out, now that enthusiasts have had some time to actually try eating the fake stuff. Beyond Meat stock has gone from a high of $240 to $16.
The fake meat industry is pushing hard for higher taxes on real meat, to make their fake products more competitive.
Irina Slav writes in “Hands off the Ham” how two compromised PhDs shamelessly authored an article advocating elimination of meat production – shameless, because they both have a profit motive – they’re involved with a plant-based meat substitute startup company called Impossible Foods. She winds up with this:
“So, two people who receive money from a company that sells meat substitutes find, by using climate modelling, that ending all meat production would do wonders for global emissions. A shocking outcome of no doubt rigorous scientific work. [a little sarcasm here] It would no doubt do wonders for the profits of Impossible Foods and its peers. And they need these profits. Desperately.”
…as I was writing this, I heard the White House was holding a “Methane Summit” yesterday. Oil companies not invited…
warning to parents
If your child is confused about whether to try to transition from a boy to a girl or vice versa, and you take them to a ‘trans gender’ clinic, don’t let the ‘experts’ convince you that you have to do something or your child might commit suicide. A lot of parents have knuckled under to the nonsense because they feared their child would commit suicide if they didn’t. In fact, children are being coached by transgender activists to threaten suicide if their parents won’t let them try to change gender. As it turns out, the suicide risk is actually greater AFTER a transition attempt.
Reuters did a little research and found a study that found 72 adverse event reports submitted to the FDA from 2013 through 2021 of children on puberty blockers who showed suicidal, self-injurious, or depressive behavior. (background on Reuters article here) The children were taking the drug for central precocious puberty or gender dysphoria or were simply identified as under 18.
As with the vaccine and mask mandators, question the “experts”! God loves us and made us the way we are. Trying to change it is not only a bad idea, it will cause permanent damage.
now to the main subject -
recommended - “Fearfully and Wonderfully Made”, by Dr. David Menton Dr. David Menton held a PhD in biology from Brown University and served as an award-winning professor at Washington University School of Medicine in St. Louis for 34 years.
here’s a link for some basic background on the genome - Overview of DNA, genes, and chromosomes
brief bio refresher
“Your body is made up of trillions of cells. (about1014 ) Each cell is a copy of the DNA in the first cell formed when the egg was fertilized. That single cell divided itself repeatedly to make all of the cells in your body.
Your cells need instructions to create who you are. Your DNA, genes and chromosomes work together to tell your body how to form and function.”
We have 46 chromosomes, 23 from our mother and 23 from father. Each chromosome is a DNA molecule, and carries our genes. Genes are segments of DNA that carry information to make proteins and enzymes. We have about 20,000 genes, but that’s less than 20% of our DNA. The other +80% apparently has instructions for managing the 20%. That +80% of DNA is what the study of epigenetics is all about.
Epigenetics is the study of how our behaviors, various external stimuli, and environment can cause changes that affect the way our genes work. Unlike genetic changes, epigenetic changes are reversible and do not change your DNA sequence, but they can change how your body reads a DNA sequence.
examples of epigenetics in action
Weight-lifting triggers DNA that controls the genes that make muscle protein, causing a response that makes more muscle. A cut triggers controls that cause the blood cells to clot at the site, and also an immune response to fight infection. Dehydration causes thirst. Hunger can make us drool at the sight of a juicy steak. Hundreds of things like this are going on all the time in our bodies. In each case, the DNA outside of the coded segment that makes protein is signalling whether more of that protein should be produced, and how much, and where in the body to send it.
These outside controls can also switch a gene completely off. You have genes that won’t be expressed unless something triggers the controls to express them.
human embryo
Understanding how a single cell can develop and grow into a complete human being is one of the most fascinating and challenging problems in biology.
stem cells
link to a primer on stem cells
Stem cells have all of our DNA, but have the capacity to select which parts of the DNA to activate in the right sequence and timing to form specialized cells from which the body grows. Epigenetics research is trying to figure out how the stem cells know when to do what. The instructions for that has to come from the large amount of DNA that calls the shots.
The adult human body is made up of hundreds of millions* of different types of cells specialized for different tasks. Nerve cells for the brain and nervous system; muscle cells; red blood cells to carry oxygen; white blood cells to fight infection; gut cells to absorb nutrients; cells to make hormones, cells to break down toxins; cells to store fat; cells to make hair; cells to line blood vessels. All of these highly specialized cells have to grow from unspecialized stem cells. Stem cells produce new cells by dividing [mitosis]. In the right conditions, these new cells can then continue to divide and differentiate into specialized cells. Stem cells can also divide to produce new stem cells to replace themselves. *The reason so many different kinds of cells can be made from only 20,000 genes is because the genes are often overlapping plus they can be read backwards and forward, and can be expressed in many different ways, packing in an astronomical amount of information, but that’s a story for another day.
embryonic stem cells
When a sperm and egg fuse, they form a single fertile cell. This cell begins a series of divisions into two, four, eight cells and so on to form an embryo. By about five or six days after fertilization, the embryo is called a blastocyst -- a ball of cells with a clump of stem cells inside. The first embryonic stem cells to form are totipotent. Each can form any of the cells needed to produce viable offspring, including the placenta. A few days later, as the embryo develops, the stem cells are pluripotent. They can form any of the cells found in an adult, but not additional tissues such as the placenta. After seven to eight weeks of development, when major organs have developed, the embryo becomes recognizable as a baby.
Much remains to be discovered about how an embryonic stem cell can differentiate into different kinds of specialized cells. This process involves changes in which certain genes are permanently turned on or off.
adult stem cells
Some stem cells can be found in the tissues of fully grown adults. These adult stem cells are multipotent. They can develop only into a limited range of differentiated cell types, usually within a particular tissue or organ.
the question remains – how does the cell know what is needed? The information has to be built into the DNA of the cell – that 80% (90%?) that is specialized for controlling proteins; not making proteins.
There also has to be a way of sensing, or communicating, what is happening, what is needed as a response. Also, instructions are needed for timing – when to make specialized cells, and in what quantity and what sequence.
What does this have to do with my Christian Faith? -It increases and strengthens it, when I consider how great God is.
next week - an update on a totally different topic - FedNow, CBDCs, the future of crypto and the connection between crypto, the blockchain, and AI
Wonderful post