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Our future, our universe, and other weighty topics


Monday, July 14, 2014

Half of the Blueprint for You May Be Stored Outside of Your Cells

Scientists love simple story lines. When they have a simple story line, it makes it easier for scientists to explain things on television. One simple story line is the idea that natural selection explains everything about the origin of mankind. Surely natural selection is a fundamentally important phenomenon that explains a great deal. But as I explain here, there are reasons for questioning the story line that natural selection explains everything about our origins, on the grounds that there are various refined features of the mind and spirit that are hard to explain purely through natural selection.

Another simple story loved by biological scientists is the “DNA stores the complete blueprint for you” story line. DNA is a molecule stored in the chromosomes of each of your cells. Each of your cells contains DNA that consists of about 23,000 different units of heredity called genes. A gene is a particular combination of nucleotide pairs in a DNA molecule. The diagram below shows a very simple gene. Some genes consist of much longer sequences of nucleotide pairs.


Scientists also sometimes speak as if we can explain human nature almost entirely by simply studying the genes in our DNA. We might say that scientists have enthroned the gene. There never was a formal coronation ceremony, but the gene was long ago placed on the throne. In the mind of scientists, it's not King George or King Charles; it's King Gene. In some cases, scientists have got so infatuated with the gene, that they have started to personify the gene, speaking in anthropomorphic terms, almost as if genes were people. An example is Richard Dawkin's book The Selfish Gene.

But there are several problems with such thinking. The first is that scientists haven't been terribly successful in trying to explain all human characteristics in terms of genes. After a massive effort in the 1990's, the human genome was decoded. The genome is the complete set of all genes in the human body. Think of the genome as a big book listing every gene, and its exact chemical parts. Scientists thought that decoding the human genome would be some Aladdin's Lamp that would open the door to thousands of dramatic medical breakthroughs. But the fruits of decoding the human genome have been relatively modest. There has been no great river of medical breakthroughs since the year 2000. How can that be if genes explain almost everything about us?

Another curious thing is that when the human genome was decoded, it was found that the number of human genes was much smaller than expected. Scientists thought that there might be 100,000 or more human genes, which seemed reasonable given that there are 17,000 genes in a fruit fly, 26,000 in a sea urchin, and 38,000 in the simple plant known as rice. But when the human genome was finally decoded, it was found that there were only about 23,000 human genes. Given the fact that humans are vastly more complicated than rice, how is it that we can have fewer genes, if it is really true that genes store a complete blueprint for a human?

Another difficulty is related to the fact that genes are really very simple things. A gene is just a recipe for making a particular protein in the body. So how is it that genes can explain even half of the most advanced characteristics of human beings? For example, humans have abilities or characteristics such as altruism, philosophical insight, wonder, spirituality, esthetic appreciation, amazing mathematical abilities, and an astonishing “built-in” language ability. How can such things be entirely explained in terms of us having the right proteins?

The alphabet used by genes is basically a 4-letter alphabet, which is not exactly a very rich alphabet for the deepest expression. The 4 letters in a gene's alphabet are A, C, T, and G. It is hard to imagine some combination of those 4 letters being responsible for each of the more subtle and refined characteristics of human nature.

Given these issues, it may be time to consider a rather drastic possibility – the possibility of dethroning the gene. We could start thinking along these lines:

Genes are a very important determinant of human nature. But as they are merely recipes for making proteins, we cannot at all explain all the exquisite features of human nature by assuming that the secrets of human nature are all stored in merely 23,000 genes. There may well be some completely undiscovered information storehouse that also is crucial in determining human nature – an unknown noncellular “dark genome.” When a human body and a full human mind comes into existence, it may require information from cellular genes and this mysterious noncellular“dark genome.”

This would be a bitter pill for scientists to swallow, because they would have to eat some humble pie. Rather than claiming they have found the book that explains everything about human nature, they would have to say: “We have found one important book that helps to explain human nature, but human nature is also explained by at least one other important book that we have not yet discovered.”

If such an undiscovered dark genome exists, where might it exist? We don't know. It could exist in cells, in some undiscovered part outside of chromosomes. Or, more likely, it could exist entirely outside of cells. Such a dark genome might be stored in some larger cosmic information system. As I explain here, here, and here, there are strong reasons for believing that there may be some cosmic information system that has helped to facilitate the universe's astonishing evolution, its improbable transition from the ultra-hot density of the Big Bang to its current orderly state. Such an information system would have three basic required elements: programming, a database engine, and a computing engine. A tiny fraction of the data within such a database system may be an undiscovered dark genome storing instructions on how to make a human being and a human mind, instructions too complicated to be written in the simple 4-letter language used by the genes in our cells.

Scientists studying the universe tried to make everything work without assuming anything other than known ordinary matter. Eventually they realized there was no way to do that. So to explain things, they came up with the vague notions of dark matter and dark energy, the characteristics of which are unknown. Biologists may eventually have to do something similar. They may have to conclude that the known genome in our cells is simply insufficient to explain all of human characteristics, particularly the subtle and refined abilities of the human mind. Just as cosmologists were forced to adopt the vague notions of undiscovered dark energy and undiscovered dark matter, biologists may have to one day adopt the vague idea that outside of our cells there is an undiscovered dark genome which stores part of the blueprint for human beings. 

Postscript: Scientists just announced that they had decoded the genome for wheat.  According to this news item, "The wheat genome also is more than five times larger than the human genome, the researchers noted." If our genes store the whole blueprint for us humans, how can we have only one fifth as many genes as something as simple as wheat?

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