L'argument des personnes qui veulent à tout prix ne voir aucune différence génétique entre les humains et les groupes d'humains, ne voir que de la diversité génétique dans un même ensemble, est d'une grande stupidité.
Ils reconnaissent que cinq à 15 % des gènes sont responsables des aspects phénotypiques des différentes ethnies ou races c'est-à-dire caucasien, asiatique, noir, océanien et indien.
Leur argument est que cela est trop peu, représente trop peu de quantité d'informations pour définir différentes races. Dans le même temps ils reconnaissent que très peu de gènes diffèrents entre les singes les plus évolués et l'espèce humaine. Environ trois à 5 %.
Ainsi trois à 5 % de gènes différents pourrait faire en sorte qu'une nouvelle espèce voit le jour et cinq à 15 % ne suffiraient pas à différencier des populations différentes d'homo sapiens, ne pourraient pas justifier l'utilisation du mot race ?
Ainsi trois à 5 % de gènes différents pourrait faire en sorte qu'une nouvelle espèce voit le jour et cinq à 15 % ne suffiraient pas à différencier des populations différentes d'homo sapiens, ne pourraient pas justifier l'utilisation du mot race ?
En réalité il existe des ethnies ou des races ayant des différences génétiques sensibles qu'elles soient phénotypiques ou autres et bien évidemment ces différences sont nées de l'adaptation des humains à des niches écologiques dans lesquelles ils ont vécu et se sont multipliés très longtemps.
Ces races ou ethnies ne sont ni supérieures ni inférieures, ne sont ni plus ni moins humaines mais en revanche il est certain qu'un noir est plus adapté à la vie en Afrique qu'un norvégien et qu'un européen du Nord est plus adapté à la vie en Suède qu'un noir.
http://plato.stanford.edu/entries/race/
"an African American is more likely to find a bone marrow match from a pool of African American donors than from a pool of white donors. "
"In summary, from a very large study of four major racial/ethnic groups within the United States and Taiwan, we found extraordinary correspondence between SIRE and genetic cluster categories but only modest geographic differentiation within each race/ethnicity group. This result indicates that studies using genetic clusters instead of racial/ethnic labels are likely to simply reproduce racial/ethnic differences, which may or may not be genetic. On the other hand, in the absence of racial/ethnic information, it is tempting to attribute any observed difference between derived genetic clusters to a genetic etiology. Therefore, researchers performing studies without racial/ethnic labels should be wary of characterizing difference between genetically defined clusters as genetic in origin, since social, cultural, economic, behavioral, and other environmental factors may result in extreme confounding (Risch et al. 2002).appendix A"
http://plato.stanford.edu/entries/race/
"an African American is more likely to find a bone marrow match from a pool of African American donors than from a pool of white donors. "
"In summary, from a very large study of four major racial/ethnic groups within the United States and Taiwan, we found extraordinary correspondence between SIRE and genetic cluster categories but only modest geographic differentiation within each race/ethnicity group. This result indicates that studies using genetic clusters instead of racial/ethnic labels are likely to simply reproduce racial/ethnic differences, which may or may not be genetic. On the other hand, in the absence of racial/ethnic information, it is tempting to attribute any observed difference between derived genetic clusters to a genetic etiology. Therefore, researchers performing studies without racial/ethnic labels should be wary of characterizing difference between genetically defined clusters as genetic in origin, since social, cultural, economic, behavioral, and other environmental factors may result in extreme confounding (Risch et al. 2002).appendix A"
http://www.sciencedirect.com/science/article/pii/S0002929707625786
Mais qu'en pensent les autres humains? En effet le singularisme intellectuel français nous réserve souvent de mauvaises surprises.
En 2003, l'université Stanford a publié une étude dont le but était de vérifier la validité du concept de race humaine, dans le cadre de l'autodéclaration en vigueur aux États-Unis50. Leur conclusion est que l'auto-identification raciale est assez précise pour continuer à être utilisée dans le cadre médical.
Mais qu'en pensent les autres humains? En effet le singularisme intellectuel français nous réserve souvent de mauvaises surprises.
En 2003, l'université Stanford a publié une étude dont le but était de vérifier la validité du concept de race humaine, dans le cadre de l'autodéclaration en vigueur aux États-Unis50. Leur conclusion est que l'auto-identification raciale est assez précise pour continuer à être utilisée dans le cadre médical.
En 2008, la revue Science a publié l'étude génomique la plus complète jamais effectuée. Cette étude compare 650 000 nucléotides chez 938 individus appartenant à 51 ethnies. Les nombreux généticiens qui ont participé à ce travail ont conclu de leurs travaux qu'il existait sept groupes biologiques parmi les humains : les Africains subsahariens, les Européens, les habitants du Moyen-Orient, ceux d'Asie centrale et d'Asie du Sud, les Asiatiques de l'Est, les Océaniens et les Amérindiens.
Interviewer - Stewart Wills The worldwide genetic diversity of humans is a matter of both basic biology and how humans have moved across the globe over time. DNA studies can provide insights into both dimensions. Now, a team of researchers from Stanford University has put together the largest genetic exploration of human diversity yet. I spoke with two of the study's authors, Richard Myers and Gregory Barsh, about the work and its significance. Dr. Myers began with a quick description of what the work was all about. Interviewee – Richard Myers What we did was, we measured genetic variation in more than a half a million places around the human genome, in almost a thousand people whose DNA had been collected by geneticists over a several-decade period, led by Luca Cavalli-Sforza here at Stanford. And this culminated in the formation of a group called the Human Genome Diversity Project – these are the samples that we analyzed. These people are from 51 regions, really spread around the world; although there are regions that are not well covered, it shows a, quite a bit of diversity from around the whole planet. What we did was that, by measuring the genetic variation of each of these loci – which is now made possible by very recent technology, to do this fast and cheap and accurately – we were able to get a picture of the genetic differences and similarities between people in these populations from around the world, at much, much, much greater detail than had been measured before. Interviewer - Stewart Wills So you mentioned the Human Genome Diversity Panel that you, that you used – what made that population a particularly good vehicle for studying this kind of thing? Interviewee - Richard Myers These 51 groups, regions of the world, were places where geneticists and anthropologists worked together over several decades collecting DNA samples from individuals who came from those regions. And what’s particularly useful about this is that they are from all over the planet, not just in one continent or one region. Interviewee – Gregory Barsh Right – what really makes the panel unique and different from what’s been done before is the large number of individuals and their diversity in terms of the different regions around the planet where they’re from. I think it’s worth comparing that to another very large group of individuals that has formed the basis for many disease studies, genetic disease studies; it’s called the HapMap. And the HapMap is based on four populations, two of whom are very closely related. And what’s different about the HGDP sample is it’s based on 51 populations, who when we into it, we really didn’t know how they were related to one another. Interviewer - Stewart Wills So this is potentially a much, a much bigger sort of window into human diversity generally. Interviewee – Gregory Barsh Absolutely. Interviewer - Stewart Wills Well let’s drill down now a little bit more into what your group specifically did with these samples. What, how did you go about studying them to kind of, to kind of address this problem? Interviewee - Richard Myers What we did was we took the DNA – and by “we” I mean 2 senior scientists in our group at the Stanford Human Genome Center, Dr. Jun Li and Dr. Devin Absher – and what, what Jun and Devon did was they took the DNA, and by using a genotyping system, we measured DNA sequence variation at 650,000 loci, or 650,000 regions of the genome, that were known to vary in at least the HapMap populations. These are all singlenucleotide polymorphisms, or single bases that differ – they’ll have either an A or a G for instance at a particular position. Interviewer - Stewart Wills So you were starting out with what had already been found about specific parts of the genome where these single nucleotide variations were common, and then you were, you were looking at those specific areas across this larger, more diverse data set. Interviewee - Richard Myers That’s exactly right. And so then – we call that genotyping, of course – and so we genotyped these individuals – about 1,000 individuals. We actually chose the thousand of that set of the Human Genome Diversity Panel that were from the 51 populations, none of whom were related to each other, at least not related to each other in very recent history. Obviously we’re all related to each other, and that’s one of the things you learn from this type of study. And so, we collected those data, and that actually only took a several-month period for us to. But then we spent a lot more time analyzing the data. Interviewer - Stewart Wills What are some of the more interesting things that you have found about human genetic diversity and populations in looking at these data? Interviewee – Gregory Barsh Well, I think that one of the most interesting things is the realization that we are, in fact, all related to one another. And looking at the way in which these 650,000 places in the genome vary, tells us the ways in which we’re related. One of the striking things to emerge from the analysis is that many people in populations that we would have thought of as relatively homogenous, actually have ancestors or ancestry from multiple different continents, and that’s particularly apparent in the Middle East. And in retrospect that makes sense because the Middle East, of course, has served as a bridge as early humans migrated out of Africa into Europe. And that’s reflected now when we look at populations that are in the Middle East, and we see well where are their ancestors from, in an agnostic way, that is – you know, let their DNA sequence tell us where their ancestors are from. And we see ancestry in Middle Eastern populations from both Africa and Europe. Another very nice example is the relationship between the Yakut population and Native American populations. And that, of course, makes lots of sense when we think about the origin of Native American populations. I think it’s also worth stating explicitly that the study adds to the now I would say overwhelming support that we have for the notion of where humans are from initially – that is, early humans really first appeared in Africa and then populated the rest of the world as they migrated out of Africa. Interviewer - Stewart Wills Well, we’ve talked a bit about population – does this help us also in genomic medicine? Interviewee - Richard Myers Having the ability to understand the genetic variation within groups will help us in genetic disease studies. One of the biggest problems, and I’ll let Greg elaborate on this, but one of the biggest problems is that when you don’t take population or geographic origin into account in a, in a large genetic study for studying something like heart disease, one of the complex traits for instance, you end up confounding the study such that you don’t actually get real signals. Interviewee – Gregory Barsh It’s clear that many important common human diseases vary in their incidence among different populations. And sometimes that clearly is due to culture – for example, the incidence of obesity in western society. You know, other times it’s probably due to genetic differences between populations. And many times it’s probably due to a combination of environment and ancestry. And figuring out what the ancestry is for any human on the planet is really a prerequisite to deconvoluting the interrelationship between ancestry and environment in understanding common human diseases. Interviewer - Stewart Wills Gregory Barsh and Richard Myers are the authors, with nine colleagues, of a new study that provides the most detailed description to date of human genetic diversity. The paper appears in the February 22nd issue of Science.
http://www.sciencemag.org/content/319/5866/1100.short
http://www.sciencemag.org/content/suppl/2008/02/21/319.5866.1118b.DC1/SciencePodcast_080222.pdf
A very interesting paper:
http://ann.sagepub.com/content/661/1/65.abstract
Encore un super papier de Risch sur les clusters:
http://www.genetics.org/content/200/4/1285.abstract#corresp-1
Mais comment arrivent ils à séparer à différencier les européens des asiatiques, sinon par des clusters de gènes partagés.
http://www.sciencemag.org/content/346/6213/1113.abstract
Le débat sur les réseaux sociaux:
Interviewer - Stewart Wills The worldwide genetic diversity of humans is a matter of both basic biology and how humans have moved across the globe over time. DNA studies can provide insights into both dimensions. Now, a team of researchers from Stanford University has put together the largest genetic exploration of human diversity yet. I spoke with two of the study's authors, Richard Myers and Gregory Barsh, about the work and its significance. Dr. Myers began with a quick description of what the work was all about. Interviewee – Richard Myers What we did was, we measured genetic variation in more than a half a million places around the human genome, in almost a thousand people whose DNA had been collected by geneticists over a several-decade period, led by Luca Cavalli-Sforza here at Stanford. And this culminated in the formation of a group called the Human Genome Diversity Project – these are the samples that we analyzed. These people are from 51 regions, really spread around the world; although there are regions that are not well covered, it shows a, quite a bit of diversity from around the whole planet. What we did was that, by measuring the genetic variation of each of these loci – which is now made possible by very recent technology, to do this fast and cheap and accurately – we were able to get a picture of the genetic differences and similarities between people in these populations from around the world, at much, much, much greater detail than had been measured before. Interviewer - Stewart Wills So you mentioned the Human Genome Diversity Panel that you, that you used – what made that population a particularly good vehicle for studying this kind of thing? Interviewee - Richard Myers These 51 groups, regions of the world, were places where geneticists and anthropologists worked together over several decades collecting DNA samples from individuals who came from those regions. And what’s particularly useful about this is that they are from all over the planet, not just in one continent or one region. Interviewee – Gregory Barsh Right – what really makes the panel unique and different from what’s been done before is the large number of individuals and their diversity in terms of the different regions around the planet where they’re from. I think it’s worth comparing that to another very large group of individuals that has formed the basis for many disease studies, genetic disease studies; it’s called the HapMap. And the HapMap is based on four populations, two of whom are very closely related. And what’s different about the HGDP sample is it’s based on 51 populations, who when we into it, we really didn’t know how they were related to one another. Interviewer - Stewart Wills So this is potentially a much, a much bigger sort of window into human diversity generally. Interviewee – Gregory Barsh Absolutely. Interviewer - Stewart Wills Well let’s drill down now a little bit more into what your group specifically did with these samples. What, how did you go about studying them to kind of, to kind of address this problem? Interviewee - Richard Myers What we did was we took the DNA – and by “we” I mean 2 senior scientists in our group at the Stanford Human Genome Center, Dr. Jun Li and Dr. Devin Absher – and what, what Jun and Devon did was they took the DNA, and by using a genotyping system, we measured DNA sequence variation at 650,000 loci, or 650,000 regions of the genome, that were known to vary in at least the HapMap populations. These are all singlenucleotide polymorphisms, or single bases that differ – they’ll have either an A or a G for instance at a particular position. Interviewer - Stewart Wills So you were starting out with what had already been found about specific parts of the genome where these single nucleotide variations were common, and then you were, you were looking at those specific areas across this larger, more diverse data set. Interviewee - Richard Myers That’s exactly right. And so then – we call that genotyping, of course – and so we genotyped these individuals – about 1,000 individuals. We actually chose the thousand of that set of the Human Genome Diversity Panel that were from the 51 populations, none of whom were related to each other, at least not related to each other in very recent history. Obviously we’re all related to each other, and that’s one of the things you learn from this type of study. And so, we collected those data, and that actually only took a several-month period for us to. But then we spent a lot more time analyzing the data. Interviewer - Stewart Wills What are some of the more interesting things that you have found about human genetic diversity and populations in looking at these data? Interviewee – Gregory Barsh Well, I think that one of the most interesting things is the realization that we are, in fact, all related to one another. And looking at the way in which these 650,000 places in the genome vary, tells us the ways in which we’re related. One of the striking things to emerge from the analysis is that many people in populations that we would have thought of as relatively homogenous, actually have ancestors or ancestry from multiple different continents, and that’s particularly apparent in the Middle East. And in retrospect that makes sense because the Middle East, of course, has served as a bridge as early humans migrated out of Africa into Europe. And that’s reflected now when we look at populations that are in the Middle East, and we see well where are their ancestors from, in an agnostic way, that is – you know, let their DNA sequence tell us where their ancestors are from. And we see ancestry in Middle Eastern populations from both Africa and Europe. Another very nice example is the relationship between the Yakut population and Native American populations. And that, of course, makes lots of sense when we think about the origin of Native American populations. I think it’s also worth stating explicitly that the study adds to the now I would say overwhelming support that we have for the notion of where humans are from initially – that is, early humans really first appeared in Africa and then populated the rest of the world as they migrated out of Africa. Interviewer - Stewart Wills Well, we’ve talked a bit about population – does this help us also in genomic medicine? Interviewee - Richard Myers Having the ability to understand the genetic variation within groups will help us in genetic disease studies. One of the biggest problems, and I’ll let Greg elaborate on this, but one of the biggest problems is that when you don’t take population or geographic origin into account in a, in a large genetic study for studying something like heart disease, one of the complex traits for instance, you end up confounding the study such that you don’t actually get real signals. Interviewee – Gregory Barsh It’s clear that many important common human diseases vary in their incidence among different populations. And sometimes that clearly is due to culture – for example, the incidence of obesity in western society. You know, other times it’s probably due to genetic differences between populations. And many times it’s probably due to a combination of environment and ancestry. And figuring out what the ancestry is for any human on the planet is really a prerequisite to deconvoluting the interrelationship between ancestry and environment in understanding common human diseases. Interviewer - Stewart Wills Gregory Barsh and Richard Myers are the authors, with nine colleagues, of a new study that provides the most detailed description to date of human genetic diversity. The paper appears in the February 22nd issue of Science.
http://www.sciencemag.org/content/319/5866/1100.short
http://www.sciencemag.org/content/suppl/2008/02/21/319.5866.1118b.DC1/SciencePodcast_080222.pdf
A very interesting paper:
http://ann.sagepub.com/content/661/1/65.abstract
Encore un super papier de Risch sur les clusters:
http://www.genetics.org/content/200/4/1285.abstract#corresp-1
Mais comment arrivent ils à séparer à différencier les européens des asiatiques, sinon par des clusters de gènes partagés.
http://www.sciencemag.org/content/346/6213/1113.abstract
Le débat sur les réseaux sociaux:
Et le super papier de Nicholas Wade
Race determination by hair
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