Synopsis
Book by DAdamo Dr Peter J Catherine Whitney
Extrait
CHAPTER ONE
Your Genetic Autobiography
You and Your Prenatal Environment
At conception, you become a fetus, with your very own set of genes. Your town meeting is populated and you’re ready to spend the next nine months in the womb, interacting with your prenatal environment–amniotic fluid, placenta, and a host of other influences. You’ll also respond to your prenatal “diet”–the nutrition you take in through what your mother eats and makes available to you. So right from the beginning, your town meeting is under way, with diet, environment, and genes beginning their lively debate.
This debate has enormous significance for the being who will emerge into the world nine months later. For example, your genetic potential at conception encoded a certain range of arterial flexibility. But how strong will your arteries be, and how flexible? A lot of the answers to those questions depend on what happens in the womb.
So that’s one of your first town meetings. The genes that encode the delicate branching architecture of your nerves and arteries show up, ready to take part. And there are our friends, environment and diet, up there on the platform as they will be throughout your life, helping your “cardiovascular genes” and “nerve genes” decide what to do. A good diet with lots of protein and healthy fats will encourage your artery genes to make your arteries rugged and elastic. On the other hand, if your mother is unlucky enough to be living in a famine, your “artery genes” will have to compete for those scarce nutrients with the genes that control the growth of other organs and tissues. The result might be a greater tendency for heart disease or high blood pressure. As you can see, the same genes are always at the meeting, but they’re responding very differently to the information given by diet and environment.
Obviously, the health of your arteries is only one of the ways that your tissues and organs are affected by your time in the womb. Those crucial nine months help determine whether you gain weight at the drop of a hat or lose weight far too easily. They help nudge you toward a hair-trigger immune response that views the entire world as its enemy, or toward a welcoming immune response that may not always know which invaders to turn away. They predispose you to certain foods that you’ll be able to digest easily and turn you away from others that won’t suit your particular metabolism and digestive tract. Right from the beginning, your genes interact with diet (in this case, Mom’s) and environment (in this case, the womb) to determine who you are.
And then you’re born. This is the point at which your GenoType is determined. Your GenoType represents your survival strategy, the decisions that have been reached collectively among your genetic potential, your prenatal diet, and your environment. Although the town meeting will continue for the rest of your life, with genes getting louder and softer in response to diet and environment, certain elements of this meeting are now fixed. They’ve formed certain patterns–one of six patterns, to be exact, which I’ve identified as the six human GenoTypes.
GenoTypes: A Human Survival Strategy
So far, we’ve been telling the story from an individual point of view–yours, to be exact. But since everyone in the world falls into one of those six GenoTypes, let’s step back for a moment and see where these GenoTypes came from.
In the beginning was the environment–a challenging place for our ancestors, to be sure. People had to make sure they could get enough food, that they could survive whatever climate they were born in or migrated to, and that they could resist infections from microbes, bacteria, and viruses.
Genetic inheritance played a crucial role in this survival. People with helpful genes survived; people with less helpful genes died. You’ve probably heard of this particular aspect of evolution as “survival of the fittest.”
Actually, survival of the fittest is more a fantasy than a reality. If only we humans were the fittest possible examples of our species, we’d all be a lot healthier, and I might be out of a job! In fact, evolution is more like a game of chance than any true contest. Sometimes the good players win; sometimes it’s just the lucky ones who survive. Sure, a lot of our genetic inheritance helps us beat the odds, but there’s also a big chunk of it that gets in our way or doesn’t play any useful role at all:
1. Sometimes the “good genes” that help us survive also have their downside. The genes that instruct our immune systems to react swiftly to bacterial invasion also overreact to produce allergies, asthma, and rheumatoid arthritis. The genes that instruct our fat cells to hang on to every calorie in order to survive a famine also contribute to obesity and diabetes. The genes that program our immune systems to respond calmly to the environment, enabling us to tolerate a wide set of circumstances without getting sick, also tell that immune system to tolerate some deadly invaders that it ought to repel.
2. Sometimes mutations simply “happen.” Our genes are designed to reproduce themselves in exact copies, but of course, that’s not always how it works. Sometimes a gene reproduces slightly differently and that variation becomes part of our genetic heritage. Skin color probably emerged this way, as a mutation of the gene that determines skin pigment. Although originally we all had dark skin, those of us living in northern climates were better able to absorb vitamin D from the scarce sunlight if our skin was lighter; we also had less need of the darker pigment’s protective function. So having lighter skin was a mutation that survived because it actually did contribute to our survival.
To some extent, though, these mutations were just random, such as the mutations that produced such diseases as Huntington’s chorea or Tay-Sachs. Or, sometimes, they represent a trade-off between the lesser of two evils. For example, having sickle-cell anemia seems to be somewhat protective against malaria, so people with the genetic tendency to have one disease are meanwhile being protected against another.
As you can see, some mutations make our lives better, some make them worse, and some probably don’t make much difference either way. But the “bad” or “neutral”mutations don’t necessarily die out, and as we’ll see in a moment, the good ones don’t necessarily survive.
3. Sometimes who survives is just the luck of the draw. If all the strong young men die in a huge battle, the male survivors are not necessarily the healthiest–but they will have lived the longest. If an avalanche destroys three-fourths of a village, the remaining one-fourth who stagger down the mountain may be more lucky than fit. There is also what scientists call the “founder effect”: When a small group splits off from a larger group and migrates to a distant land, its members may carry only a fraction of the original population’s genetic potential. Whatever genes they managed to take away from the larger group, those are the ones that survive–and they’re not necessarily “the fittest.” Nevertheless, these are the survivors, the ones who pass their genetic inheritance down to the rest of us.
Why should you care about any of this? Because the final effect of this whole process has been our six GenoTypes, which are extremely useful but very imperfect strategies for survival. Every GenoType has its upside and its downside. I personally can imagine ways to improve every single one of them, and once you get to know them better, I’m sure you will, too. In fact, that’s the point of this book: What the GenoTypes have begun, we can complete, maximizing their strengths and minimizing their weaknesses through diet, supplements, and exercise.
Remember, your genes don’t stay fixed in their tracks. Instead, they keep reshaping themselves and you, just as they did when you were in the womb. Your cells are constantly reading the environment they’re in and altering their functions accordingly: Toxic or safe? Food-rich or barren? Threatening or welcoming? These conditions prompt your cells to turn various genes on and off, depending on how the environment is affecting them. These instructions are implemented at the town meeting, where the volume is turned up on some genes and turned down on others.
The end result is our six GenoTypes, each of which has its own unique pattern of “noisy” and “silent” genes. Accordingly, each of our six GenoType Diets is designed to alter that pattern to promote your optimal health and weight.
Meet the GenoTypes
So let’s take a closer look at these GenoTypes. What possibilities for human survival are encoded within these genetic and prenatal patterns? Before I introduce you to the GenoTypes, I want to caution you against two common mistakes. First, these GenoTypes do not correlate in any way to ethnic patterns. They seem to have developed tens of thousands of years before ethnicity emerged, and with the exception of the Nomad GenoType, which seems to have more than its fair share of redheads, they don’t follow any of the statistical patterns that do correlate with ethnicity, skin color, eye color, hair texture, hair color, ancestry information markers, mitochondrial DNA, Y-chromosome DNA, and a host of others with far more technical names. In the end, I could find only a
few weak links with some of the ancestral DNA markers but absolutely no correlation with ethnicity–none. Just as anyone can be hot-tempered or optimistic, anyone can be any one of these GenoTypes, no matter their racial or ethnic identity or who their ancestors are. (And, just to make this crysta...
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