Cheetah genes cooperate with cheetah genes but not with camel genes, and vice versa. This is not because cheetah genes, even in the most poetic sense, see any virtue in the preservation of the cheetah species. They are not working to save the cheetah from extinction like some molecular World Wildlife Fund.
Complex organisms cannot be construed as the sum of their genes, nor do genes alone build particular items of anatomy or behavior by themselves. Most genes influence several aspects of anatomy and behavior as they operate through complex interactions with other genes and their products, and with environmental factors both within and outside the developing organism. We fall into a deep error, not just a harmful oversimplification, when we speak of genes "for" particular items of anatomy or behavior.
Stephen Jay Gould
If these d'Herelle bodies were really genes, fundamentally like our chromosome genes, they would give us an utterly new angle from which to attack the gene problem. They are filterable, to some extent isolable, can be handled in test-tubes, and their properties, as shown by their effects on the bacteria, can then be studied after treatment. It would be very rash to call these bodies genes, and yet at present we must confess that there is no distinction known between the genes and them. Hence we can not categorically deny that perhaps we may be able to grind genes in a mortar and cook them in a beaker after all. Must we geneticists become bacteriologists, physiological chemists and physicists, simultaneously with being zoologists and botanists? Let us hope so.
Hermann Joseph Muller
Individuals are not stable things, they are fleeting. Chromosomes too are shuffled into oblivion, like hands of cards soon after they are dealt. But the cards themselves survive the shuffling. The cards are the genes. The genes are not destroyed by crossing-over, they merely change partners and march on. Of course they march on. That is their business. They are the replicators and we are their survival machines. When we have served our purpose we are cast aside. But genes are denizens of geological time: genes are forever.
Epigenetics doesn't change the genetic code, it changes how that's read. Perfectly normal genes can result in cancer or death. Vice-versa, in the right environment, mutant genes won't be expressed. Genes are equivalent to blueprints; epigenetics is the contractor. They change the assembly, the structure.
The essential quality that an entity needs, if it is to become an effective gene vehicle, is this. It must have an impartial exit channel into the future, for all the genes inside it. This is true of an individual wolf. The channel is the thin stream of sperms, or eggs, which it manufactures by meiosis. It is not true of the pack of wolves. Genes have something to gain from selfishly promoting the welfare of their own individual bodies, at the expense of other genes in the wolf pack. A bee-hive, when it swarms, appears to reproduce by broad-fronted budding, like a wolf pack. But if we look more carefully we find that, as far as the genes are concerned, their destiny is largely shared. The future of the genes in the swarm is, at least to a large extent, lodged in the ovaries of one queen. This is why-it is just another way of expressing the message of earlier chapters-the bee colony looks and behaves like a truly integrated single vehicle.
Realizing the ways in which we humans may have been inadvertently changing our genes for millennia provides a way for us to begin to think about the inevitable genetic revolution in medicine that is going to allow us to advertently change our genes over centuries and even decades.
Nicholas A. Christakis
While nobody has identified any gene for religion, there are certainly some candidate genes that may influence human personality and confer a tendency to religious feelings. Some of the genes likely to be involved are those which control levels of different chemicals called neurotransmitters in the brain.
Suddenly I realized that a cell's life is controlled by the physical and energetic environment and not by its genes. Genes are simply molecular blueprints used in the construction of cells, tissues, and organs. The environment serves as a "contractor" who reads and engages those genetic blueprints and is ultimately responsible for the character of a cell's life. It is a single cell's "awareness" of the environment, not its genes, that sets into motion the mechanisms of life.
Bruce H. Lipton
Different sorts of survival machine appear very varied on the outside and in their internal organs. An octopus is nothing like a mouse, and both are quite different from an oak tree. Yet in their fundamental chemistry they are rather uniform, and, in particular, the replicators that they bear, the genes, are basically the same kind of molecule in all of us-from bacteria to elephants. We are all survival machines for the same kind of replicator-molecules called DNA- but there are many different ways of making a living in the world, and the replicators have built a vast range of machines to exploit them. A monkey is a machine that preserves genes up trees, a fish is a machine that preserves genes in the water; there is even a small worm that preserves genes in German beer mats. DNA works in mysterious ways.
The implication is that this basic idea we have that we are controlled by our genes is false. It's an idea that turns us into victims. I'm saying we are the creators of our situation. The genes are merely the blueprints. We are the contractors, and we can adjust those blueprints. And we can even rewrite them.
But if it is true that human minds are themselves to a very great degree the creations of memes, then we cannot sustain the polarity of vision we considered earlier; it cannot be "memes versus us, " because earlier infestations of memes have already played a major role in determining who or what we are. The "independent" mind struggling to protect itself from alien and dangerous memes is a myth. There is a persisting tension between the biological imperative of our genes on the one hand and the cultural imperatives of our memes on the other, but we would be foolish to "side with" our genes; that would be to commit the most egregious error of pop sociobiology. Besides, as we have already noted, what makes us special is that we, alone among species, can rise above the imperatives of our genes- thanks to the lifting cranes of our memes.
Daniel C. Dennett
Human beings do not carry civilization in their genes. All that we do carry in our genes are certain capacities- the capacity to learn to walk upright, to use our brains, to speak, to relate to our fellow men, to construct and use tools, to explore the universe, and to express that exploration in religion, in art, in science, in philosophy.
Human beings are ultimately nothing but carriers-passageways- for genes. They ride us into the ground like racehorses from generation to generation. Genes don't think about what constitutes good or evil. They don't care whether we are happy or unhappy. We're just means to an end for them. The only thing they think about is what is most efficient for them.
The study of how substances alter gene expression is part of the field of epigenetics. Some chemical exposures appear to turn on and turn off genes in ways that disregulate cell growth and predispose for cancer. From this perspective, our genes are less the command-and-control masters of our cells and more like the keys of piano, with the environment as the hands of the pianist.
Random mutations much more easily debilitate genes than improve them, and that this is true even of the helpful mutations. Let me emphasize, our experience with malaria's effects on humans (arguably our most highly studied genetic system) shows that most helpful mutations degrade genes. What's more, as a group the mutations are incoherent, meaning that they are not adding up to some new system. They are just small changes - mostly degradative - in pre-existing, unrelated genes. The take-home lesson is that this is certainly not the kind of process we would expect to build the astonishingly elegant machinery of the cell. If random mutation plus selective pressure substantially trashes the human genome, why should we think that it would be a constructive force in the long term? There is no reason to think so.
Michael J. Behe
While genes are pivotal in establishing some aspects of emotionality, experience plays a central role in turning genes on and off. DNA is not the heart's destiny; the genetic lottery may determine the cards in your deck, but experience deals the hand you can play. Scientists have proven, for example, that good mothering can override a disadvantageous temperament.(152)
Charles Darwin and I and you broke off from the family tree from chimpanzees about five million years ago. They're still our closest genetic kin. We share 98.8 percent of the genes. We share more genes with them than zebras do with horses. And we're also their closest cousin. They have more genetic relation to us than to gorillas.
There is no gene "for" such unambiguous bits of morphology as your left kneecap or your fingernail. [...] Hundreds of genes contribute to the building of most body parts and their action is channeled through a kaleidoscopic series of environmental influences: embryonic and postnatal, internal and external. Parts are not translated genes, and selection doesn't even work directly on parts.
Stephen Jay Gould
Genes which allow females to be less inhibited leave fewer copies of themselves than genes which persuade them to remain highly selective. Among males, the best strategy is exactly the opposite one. The maximum advantage goes to those males with the fewest inhibitions. "Love 'em and leave 'em" is not so much a nasty peice of male chauvinist piggery as an accurate reflection of biological reality.
We can now determine, easily and relatively cheaply, the detailed chemical architecture of genes ; and we can trace the products of these genes ( enzymes and proteins ) as they influence the course of embryology . In so doing we have made the astounding discovery that all complex animal phyla - arthropods and vertebrates in particular - have retained, despite their half-billion years of evolutionary independence, an extensive set of common genetic blueprints for building bodies.
Stephen Jay Gould
Natural species are the library from which genetic engineers can work. Genetic engineers don't make new genes, they rearrange existing ones. Speaking as World Wildlife Fund Executive Vice President, stating the need to conserve biodiversity, even plants and animals having no immediate use, as a unique repository of genes for possible future biogengineering applications.
The great paradox of determinism and free will, which has held the attention of the wisest of philosophers and psychologists for generations, can be phrased in more biological terms as follows: If our genes are inherited, and our environment is a train of physical events set in motion before we were born, how can there be a truly independent agent within the brain? The agent itself is created by the interaction of the genes and the environment. It would appear that our freedom is only a self delusion.
E. O. Wilson
Genes are important because they are the blueprints for proteins, but proteins are where the action is in human life and health. This ability to find links between sets of proteins involved in different genetic disorders offers a novel approach for more rapidly identifying new candidate genes involved in human diseases.
Recently, results of the Human Genome Project have shattered one of Science's fundamental core beliefs, the concept of genetic determinism. We have been led to believe that our genes determine the character of our lives, yet new research surprisingly reveals that it is the character of our lives that controls our genes. Rather than being victims of our heredity, we are actually masters of our genome.
Bruce H. Lipton
The choices you make each day in your diet and lifestyle have a direct influence on how your genetic predisposition is expressed - for better and for worse. You're only as old as your genes, but how your genes are expressed may be modified by exercise, diet and lifestyle choices much more than had previously been believed - and more quickly.