posted
Science 16 February 2001: Vol. 291. no. 5507, pp. 1219 - 1220
Viewpoint GENOMICS AND SOCIETY:
The Human Genome and Our View of Ourselves
Svante Pääbo*
Perhaps for the pragmatic biologist, the determination of the human genome sequence is a prosaic event--the delivery of a wonderfully powerful tool, but a tool nonetheless. For the general public, however, the human genome sequence is of enormous symbolic significance, and its publication on page 1304 of this issue (1) and in this week's Nature (2) is likely to be greeted with the same awestruck feeling that accompanied the landing of the first human on the moon and the detonation of the first atomic bomb.
Why are certain achievements--the first lunar landing, atomic fission, the determination of the human genome sequence--imbued with such emblematic significance? The reason is, I believe, that they change how we think about ourselves. Landing a person on the moon gave us an extraterrestrial perspective on human life; atomic fission gave us the power to create enormous energy reserves and to extinguish all human life on Earth; and now the human genome sequence gives us a view of the internal genetic scaffold around which every human life is molded. This scaffold has been handed down to us from our ancestors, and through it we are connected to all other life on Earth.
How does the complete human genome sequence affect the way that we think about ourselves? Clearly, the availability of a reference human DNA sequence is a milestone toward understanding how humans have evolved, because it opens the door to large-scale comparative studies. The major impact of such studies will be to reveal just how similar humans are to each other and to other species.
The first comparisons will be between the human genome and distantly related genomes such as those of yeast, flies, worms, and mice. A glimpse of what this will show us comes from considering the fact that about 26,000 to 38,000 genes are found in the draft version of our own genome, a number that is only two to three times larger than the 13,600 genes in the fruit fly genome. Furthermore, some 10% of human genes are clearly related to particular genes in the fly and the worm. So, obviously, we share much of our genetic scaffold even with very distant relatives. The similarity between humans and other animals will become even more evident when genome sequences from organisms such as the mouse, with whom we share a more recent common ancestor, become available. For these species, both the number of genes and the general structure of the genome are likely to be very similar to ours. Although this has long been realized by insiders in the genetics community, the close similarity of our genome to those of other organisms will make the unity of life more obvious to everyone. No doubt the genomic view of our place in nature will be both a source of humility and a blow to the idea of human uniqueness.
However, the most obvious challenge to the notion of human uniqueness is likely to come from comparisons of genomes of closely related species. We already know that the overall DNA sequence similarity between humans and chimpanzees is about 99% (3). When the chimpanzee genome sequence becomes available, we are sure to find that its gene content and organization are very similar (if not identical) to our own. Perhaps it is our subconscious discomfort with this expectation that explains the slowness with which the genomics community has embraced the idea of a chimpanzee genome project. Be that as it may, with most of the human genome sequence now complete, it will be easy to determine the chimpanzee sequence using the human sequence as a guide to assembly. The result is sure to be an even more powerful challenge to the notion of human uniqueness than the comparison of the human genome to those of other mammals.
Yet the few differences between our genome and those of the great apes will be profoundly interesting because among them lie the genetic prerequisites that make us different from all other animals. In particular, these differences may reveal the genetic foundation for our rapid cultural evolution and geographic expansion, which started between 150,000 and 50,000 years ago (4) and led to our current overbearing domination of Earth. The realization that one or a few genetic accidents made human history possible will provide us with a whole new set of philosophical challenges to think about.
Large-scale comparisons of human genomes from many individuals are now possible with the emergence of high-throughput techniques for DNA sequence determination. The general picture already apparent from such studies is that the gene pool in Africa contains more variation than elsewhere, and that the genetic variation found outside of Africa represents only a subset of that found within the African continent (5). From a genetic perspective, all humans are therefore Africans, either residing in Africa or in recent exile.
In view of the sad part that race and ethnicity still play in most societies, concerns that genetic analyses of different human populations could be abused are appropriate. Fortunately, from the few studies of nuclear DNA sequences, it is clear that what is called "race," although culturally important, reflects just a few continuous traits determined by a tiny fraction of our genes. This tiny fraction gives no indication of variations at other parts of our genome. Thus, from the perspective of nuclear genes, it is often the case that two persons from the same part of the world who look superficially alike are less related to each other than they are to persons from other parts of the world who may look very different (see the figure) (6). Although small segments of the genome--such as mitochondrial DNA and Y chromosomal DNA (which are inherited in an unusual way) or the few genes that encode visible traits (which may have been selected for)--show a pattern where the genes in a particular human population can be traced back to a single common ancestor, this is not the case for the vast majority of our genes. Indeed, one way in which we humans seem to differ from apes is that we have evolved with very little subdivision. This is surely because we are a young species (in evolutionary terms) and have a greater tendency for migration than many other mammals. I suspect, therefore, that genome-wide studies of genetic variation among human populations may not be so easy to abuse--in terms of using data as "scientific support" for racism or other forms of bigotry--as is currently feared. If anything, such studies will have the opposite effect because prejudice, oppression, and racism feed on ignorance. Knowledge of the genome should foster compassion, not only because our gene pool is extremely mixed, but also because a more comprehensive understanding of how our genotype relates to our phenotype will demonstrate that everyone carries at least some deleterious alleles. Consequently, stigmatizing any particular group of individuals on the basis of ethnicity or carrier status for certain alleles will be revealed as absurd.
From a medical standpoint, improved predictive capabilities provided by the identification of disease-associated alleles harbor great potential benefits but also problems. The benefits will come from using individualized risk assessment to modify the environmental and behavioral components of common diseases. Relatively minor measures implemented early in life may prove to be extremely effective in postponing or even preventing the onset of disease. But individualized risk assessment may come at the price of "genetic hypochondria," causing many to spend their lives waiting for a disease that may never arrive. Finally, increased medical predictive power obviously represents a societal challenge in terms of medical insurance, especially in countries that, unlike most Western European countries, are not blessed with health insurance systems that share risks in an equitable fashion among the whole population. Legislators in such countries would be wise to act now to counteract future temptations to "personalize" insurance risks. Later on, once powerful genetic diagnostic tests are in place, it will be hard to withstand pressure from the insurance lobby to prevent such legislation.
As we enter a genomic era in medicine and biology, perhaps the greatest danger I see stems from the enormous emphasis placed on the human genome by the media. The successes of medical genetics and genomics during the last decade have resulted in a sharp shift toward an almost completely genetic view of ourselves. I find it striking that 10 years ago, a geneticist had to defend the idea that not only the environment but also genes shape human development. Today, one feels compelled to stress that there is a large environmental component to common diseases, behavior, and personality traits! There is an insidious tendency to look to our genes for most aspects of our "humanness," and to forget that the genome is but an internal scaffold for our existence.
We need to leave behind the view that the genetic history of our species is the history par excellence. We must realize that our genes are but one aspect of our history, and that there are many other histories that are even more important. For example, many people in the Western world feel a connection to ancient Greece, from which arose fundamental features of Western architecture, science, technology, and political ideals (such as democracy). Yet, at best a tiny fraction of the gene pool of the Western industrialized world came from the ancient Greeks. Obviously, this fact in no way diminishes the importance of ancient Greece. So it is a delusion to think that genomics in isolation will ever tell us what it means to be human. To work toward that lofty goal, we need an approach that includes the cognitive sciences, primatology, the social sciences, and the humanities. But with the availability of the complete human genome sequence now at hand, genetics is in a prime position to play a prominent part in this endeavor.
References
J. C. Venter et al., Science 291, 1304 (2001). International Human Genome Sequencing Consortium, Nature 409, 860 (2001). M.-C. King, A. C. Wilson, Science 188, 107 (1975) [Medline]. R. G. Klein, The Human Career (Univ. of Chicago Press, Chicago, IL, 1999) [publisher's information]. L. B. Jorde, M. Bamshad, A. R. Rogers, Bioessays 20, 126 (1998) [Medline]. H. Kaessmann, F. Heissig, A. von Haeseler, S. Pääbo, Nature Genet. 22, 78 (1999) [Medline].
-------------------------------------------------------------------------------- The author is at the Max Planck Institute for Evolutionary Anthropology, Leipzig, Germany. E-mail: paabo@eva.mpg.de
Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by Evergreen: We must realize that our genes are but one aspect of our history, and that there are many other histories that are even more important. For example, many people in the Western world feel a connection to ancient Greece, from which arose fundamental features of Western architecture, science, technology, and political ideals (such as democracy). Yet, at best a tiny fraction of the gene pool of the Western industrialized world came from the ancient Greeks. Obviously, this fact in no way diminishes the importance of ancient Greece.
Evergreen Writes:
We must realize that our genes are but one aspect of our history, and that there are many other histories that are even more important. For example, many people in the African world feel a connection to ancient Egypt, from which arose fundamental features of African architecture, science, technology, and political ideals. Yet, at best a tiny fraction of the gene pool of the African world came from the ancient Egyptians. Obviously, this fact in no way diminishes the importance of ancient Egypt to Africa.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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posted
Evergreen – I’m sure that you mean well, but you seem to have things backwards.
Evergreen Writes:
We must realize that our genes are but one aspect of our history, and that there are many other histories that are even more important. For example, many people in the African world feel a connection to ancient Egypt, from which arose fundamental features of African architecture, science, technology, and political ideals. Yet, at best a tiny fraction of the gene pool of the African world came from the ancient Egyptians. Obviously, this fact in no way diminishes the importance of ancient Egypt to Africa.
The Egyptians came FROM the African gene pool, not the other way around. The fundamental features of African architecture, science, and technology as produced by the original civilizations did not find their way to the Africa that you speak of – Sub Sahara. Rather, it is the foundation for European civilization. Historically, the first evidence of democracy was by the Sumerians. The Greeks did not, and to this day have not, invented anything of note.
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Alive in the Box: I assume you response is based on the latest news from South Africa: Admittedly it is difficult to imagine the founding civilizations as being part of the same race, but they were, as has been proven many times over.
Many learned people speculate that the difference in accomplishment is based on the fact that the founding civilizations of Nubia, Egypt, Sumer (Iraq), and the Indus valley (Pakistan), were River Valley inhabitants in an otherwise sparse environment. Climatic changes forced them to congregate ever closer to the only reliable source of water – the River. This of course sparked conflict, but it also over time, forced cooperation – survival depended on it.
Over the millennia, this “forced” cooperation resulted in the creation or invention of all the things we find essential for our modern lives: i.e. Farming, Written language, Mathematics, organized Religion, Architecture, the City (Urban life), organized Government, the Wheel, the Sail, the Wagon, Cloth weaving (textiles), Wine, Beer, Cooking oil, in other words, all the things necessary for what we call civilization.
But before turning your nose too high up, you might remember that as modern Europeans first entered Europe: Hellenes/Greeks (Aeolians, Dorian’s) in about 1,200 B.C. The Latin’s or Latini (Romans) in about 1,000 B.C. The Slavs, Germans and Celts in about 500 B.C. the Turks (modern Arabs – as in modern Anatolians, Egyptians, Palestinians, Israelis, Syrians, Iraqis, Iranians), in about 200 A.D. As these people entered, they were illiterate Nomads. If they had not availed themselves of the things and methods created by the founding Civilizations (unfortunately by force), they certainly would have found themselves in the same predicament as the Sub Saharans of today.
You might also be mindful that as of the fall of the last Black Empire; the Sassanian Persian in 651 A.D. Europe did not invent anything new, until the advent of the Industrial revolution in the 1700s A.D.
You might be thinking; well what about the Gun and Gunpowder. Nope, Gunpowder was invented by the Chinese and Indians; with the Indians being the first to use it with projectiles. The first actual “Gun” was first used by Egyptians against the Mongols at the battle of Ain Jalut in 1260 A.D. You may say; well what about the first Machine: Nope again; the first documented steam-powered device, the “Aeolipile”, and also the windwheel, was invented by an Egyptian, Heron of Alexandria in 60 A.D. Hope this gives you a new prospective.
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quote:Originally posted by Mike111: Over the millennia, this “forced” cooperation resulted in the creation or invention of all the things we find essential for our modern lives: i.e. Farming, Written language, Mathematics, organized Religion, Architecture, the City (Urban life), organized Government, the Wheel, the Sail, the Wagon, Cloth weaving (textiles), Wine, Beer, Cooking oil, in other words, all the things necessary for what we call civilization.
Posts: 8014 | From: the Tekrur in the Western Sahel | Registered: Feb 2006
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What I mean is, when I think wagon I think EurAsia. May just be how my mind works but when I think wagon I think "circle the wagons" as in "how the west was won" and "the great trek."
I don't think African civilization. Certainly not Egypt, lest it be Sea Peoples women and children eking down the Levantine coast. Maybe I need to learn what I never knew before. Teach me the place of the wagon in the making of Africa's civilizations.
quote:Originally posted by Mike111: ... the creation or invention of all the things we find essential for our modern lives: i.e. ..., the Wagon, ..., in other words, all the things necessary for what we call civilization.
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posted
The Wagon and Wheel were developed in Mesopotamia and India. With the plains south of Russia being a possible origin of the device common to both.
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quote:Originally posted by Doug M: The Wagon and Wheel were developed in Mesopotamia and India. With the plains south of Russia being a possible origin of the device common to both.
Evergreen Writes:
Speaking of which, good book on the "Aryan Invasion" model -
March 2, 2008 Giddyap By CHRISTINE KENNEALLY Skip to next paragraph THE HORSE, THE WHEEL, AND LANGUAGE
How Bronze-Age Riders From the Eurasian Steppes Shaped the Modern World.
By David W. Anthony.
Illustrated. 553 pp. Princeton University Press. $35. The first and most intimate affiliations we have are the genetic ties we share with our family and the language we speak. In the first case, the links are pretty straightforward. Without exception, everyone is created by two parents, who each had two parents, who themselves had two parents, and on and on, so that behind every reader of this review, thousands of mothers and fathers fan out and multiply in a completely predictable way.
Linguistic inheritance, by contrast, is a story of irreducible patterns and historical contingencies. In “The Horse, the Wheel, and Language,” David W. Anthony argues that we speak English not just because our parents taught it to us but because wild horses used to roam the steppes of central Eurasia, because steppe-dwellers invented the spoked wheel and because poetry once had real power.
English belongs to the very large Indo-European language family. All of the Germanic, Baltic, Slavic, Celtic, Latin, Hellenic, Iranian and Sanskrit languages (among other families) are Indo-European, which means that Lithuanian, Polish, English, Welsh, French, Greek, Kurdish and Punjabi, to name just a few, descend from the same ancient tongue. It is known as Proto-Indo-European, and it was spoken around 3500 B.C. Thanks to a careful comparison of the daughter languages (as linguists call them), thousands of Proto-Indo-European words have been reconstructed, including those for otter, wolf, lynx, bee, honey, cattle, sheep and horse. The way some words group together in Proto-Indo-European shows that its speakers believed in a male sky god, respected chiefs and appointed official warriors. One word for wheel sounded something like “roteh.” The word for axle? “Aks.”
Where Proto-Indo-European came from and who originally spoke it has been a mystery ever since Sir William Jones, a British judge and scholar in India, posited its existence in the late 18th century. As a result, Anthony writes, the question of its origins was “politicized almost from the beginning.” Numerous groups, ranging from the Nazis to adherents of the “goddess movement” (who saw the Indo-Europeans as bellicose invaders who upended a feminine utopia), have made self-interested claims about the Indo-European past. Anthony, an archaeologist at Hartwick College who has extensive field experience, makes the persuasive case that it originated in the steppes of what is now southern Ukraine and Russia, a landscape consisting mainly of endless grasslands and “huge, dramatic” sky. Anthony is not the first scholar to make the case that Proto-Indo-European came from this region, but given the immense array of evidence he presents, he may be the last one who has to.
Anthony lays out crucial events that built up the economic and, later, military power of Proto-Indo-European speakers, increasing the reach and prestige of the language. It’s a linguistic version of the rich getting richer, with the result that more than three billion people around the world today speak a descendant of this mother tongue.
Perhaps the most important moment came with the domestication of horses, first accomplished around 4,800 years ago, at least 2,000 years after cattle, sheep, pigs and goats had been domesticated in other parts of the world. Initially, horses were most likely tamed to serve as an easy source of meat, particularly in winter; it wasn’t until centuries later that they were ridden, and then eventually used to pull carts with solid wheels, turning the Proto-
Indo-European speakers into mobile herders and the steppes into a conduit for themselves and their language. Later, they became skilled warriors whose spoked-wheel chariots sped them to battle and spread their language even farther.
The impact of horses on the reach of language is particularly important to Anthony, and he conveys his excitement at working out whether ancient horses wore bits (and were therefore ridden by Proto-Indo-Europeans) by comparing their teeth to those of modern domesticated and wild horses. He muses on the “deep-rooted, intransigent traditions of opposition” that existed along the Ural River frontier, slowing the spread of herding and the cultural innovations that went with it. He also cites remarkable genetic analyses suggesting that although all the domesticated horses in the world may have come from many different wild mothers, they might all share a single father.
Anthony also describes a world in which spoken poetry was the only medium, one that helped spread Proto-Indo-European through what he calls “elite recruitment.” It wasn’t enough for the newcomers to assume a dominant position: in order for their language to be picked up, they also had to offer the local population attractive opportunities to participate in their language culture — a process that continues today, incidentally, with the spread of English as a prestige language.
“The Horse, the Wheel, and Language” brings together the work of historical linguists and archaeologists, researchers who have traditionally been suspicious of one another’s methods. Though parts of the book will be penetrable only by scholars, it lays out in intricate detail the complicated genealogy of history’s most successful language.
Christine Kenneally is the author of “The First Word: The Search for the Origins of Language.”
Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by Doug M: The Wagon and Wheel were developed in Mesopotamia and India. With the plains south of Russia being a possible origin of the device common to both.
Evergreen Writes:
Speaking of which, good book on the "Aryan Invasion" model -
March 2, 2008 Giddyap By CHRISTINE KENNEALLY Skip to next paragraph THE HORSE, THE WHEEL, AND LANGUAGE
How Bronze-Age Riders From the Eurasian Steppes Shaped the Modern World.
By David W. Anthony.
Illustrated. 553 pp. Princeton University Press. $35.
"The indigenous languages of northern Syria probably belonged to the Afro-Asiatic language phylum, like Semitic and most of the languages of the lowland Near East. If the first Anatolian farmers spoke an Afro-Asiatic language, it was that language, not proto-Indo-European, that should have been carried to Greece."
"Curiously a fragment of that lost language might be preserved in the proto-Indo-European term for bull, *tawro-s, which many linguists think was borrowed from an Afro-Asiatic term. The Afro-Asiatic super-family generated both Egyptian and Semitic in the Near East, and one of its early languages might have been spoken in Anatolia by the earliest farmers. Perhaps the Cris people spoke a language of Afro-Asiatic type, and as they drove their cattle into the East Carpathian Valley they called them something like *tawr-."
Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by Evergreen: [QUOTE]Originally posted by Doug M: [qb] The Wagon and Wheel were developed in Mesopotamia and India. With the plains south of Russia being a possible origin of the device common to both.
Evergreen Writes:
Speaking of which, good book on the "Aryan Invasion" model -
March 2, 2008 Giddyap By CHRISTINE KENNEALLY Skip to next paragraph THE HORSE, THE WHEEL, AND LANGUAGE
How Bronze-Age Riders From the Eurasian Steppes Shaped the Modern World.
By David W. Anthony.
Illustrated. 553 pp. Princeton University Press. $35.
"Old Indic, the language of the Rig Veda, was recorded in inscriptions not long after 1500 BCE but in a puzzling place. Most Vedic specialists agree that the 1028 hymns of the Rig Veda were compiled into what became sacred form in the Punjab, in northwestern India and Pakistan, probably between 1500 and 1300 BCE. But the deities, moral concepts, and Old Indic language of the Rig Veda first appeared in written documents not in India but in northern Syria."
Posts: 2007 | From: Washington State | Registered: Oct 2006
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posted
Doug M - I would partially disagree with you on the matter of the Wagon. Though it is true that in Europeanized history, the Arians are said to have crossed the Himalayas with their Cars (Chariots), This is completely unbelievable. Sumerians are universally acknowledged as being the inventors of the Wheel, if you have no Wheel, how can you have a Wagon.
Thought certainly as plains people, they probably employed a travois such as below.
But for an actual Wagon, such as the Sumerian vehicle below, you need Wheels. Please note: my use of the picture does not imply my belief in the authenticity of the Standard of Ur, I have my doubts.
quote:Originally posted by Mike111: Alive in the Box: I assume you response is based on the latest news from South Africa: Admittedly it is difficult to imagine the founding civilizations as being part of the same race, but they were, as has been proven many times over.
Umm... no.
Actually, I was simply saying that I agreed with you, but the last letter got cut off.
I winked but probably would've rather gave you a thumbs up when after Evergreen phrased it "Yet, at best a tiny fraction of the gene pool of the African world came from the ancient Egyptians"you responded - "The Egyptians came FROM the African gene pool, not the other way around."
which I agreed with. Sometimes I fly through this forum, and don't stay for long but just leave a quick comment or not - it appears this one got cut off.
And I've long been out of the box - the paranthetic part of the screen name comes from some corny ass name I picked in the past: What Box?
posted
As far as the wheel and wagon, those objects were indeed invented in several early civilizations but the chariot and multi-spoked wheel was associated with people who domesticated faster moving beasts of burden-- namely the horse. As far as genetics is concerned there is no definitive proof of actual 'Aryan' migrations and the only true evidence we have of such people is there language and culture. With the evidence from Mitanni it can be taken that there was an Indo-Euroepan military elite whose language was associated with the upper-class eventually filtered to larger populaces.
Getting back to the issue of genetics, I believe tracking down the genetic lineages of living innovations i.e. domesticated plants and animals gives a great clue as to the spread of culture. There are many examples of this such as the spread of Middle Eastern grains to Africa and the spread of African cattle to the Near East and Europe, or the spread of Southeast Asian rice and poultry to the rest of Eurasia.
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