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Author | Topic: Human Races | |||||||||||||||||||||||
sfs Member (Idle past 2555 days) Posts: 464 From: Cambridge, MA USA Joined: |
quote:You used it incorrectly. There is no sense in which two humans are 15% different from each other genetically. quote:No, that means that different populations have different unique genetic characteristics (rarely -- most genetic characteristics are not unique to a population). Human geneticists distinguish populations all the time, for a variety of reasons. "Race", on the other hand, covers a range of meanings, some of which map very poorly onto genetics. The thread started out with the idea of a few "pure" races which could be mixed to produce everyone. You, on the other hand, cited genetic differences between Vikings and other northern Europeans as evidence for the usefulness of "race" as a concept. Those are not the same concept of race. Geneticists tend to avoid the term "race" because of its multiple meanings and its heavy non-scientific baggage. quote:How are they different, and why can't they be compared? (And what do you mean by "population" here? Are Africans one population or many?) quote:Then you've established a classification based on a handful of genetic traits, out of thousands. Any scheme that groups together Yoruba, San, Mbuti pygmies, Andaman Islanders and Phillipine Negritos, as racial classification usually does (they're all black or negroid), is gibberish to a geneticist.
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: Don't get hung up on the figure or it's 'reality'. The point Iwas trying to make was independent of the actual number used. That being, that the logic of the interpretation of the evidenceis flawed. The two deviation figures used are not based upon the SAME thing. quote: If two populations (however you have defined it) have differentunique genetic traits, the surely they can be characterised by those traits. What do you mean by a 'unique trait' in any case. Is, forexample since it seems the main issue here, skin colour a unique trait or a common trait? quote: Do you view that as not logivally possible, or as unsuported/refutedby evidence? quote: What makes them different? I'm sure that Vikings viewed themselves as a distinct race,and they were certainly viewed that way by the other peoples of Europe. One might see a tall blonde or ginger person and say 'That's a Viking.' -- racial characterisation based upon a handful of common traits that are uncommon in other 'races'. quote: There are more reasons than that for avoiding the term, manyof which are political. quote: Africa is a huge continent and is composed of a large numberof separate populations. Interestingly this is how Africans I have met view it. I was speaking to a student from Africa once and asked him if he knew another African student -- the reply was 'I don't speak to him, he's Nigerian!' I suppose by population I mean any group which has signifcantinteractions between individuals. Without knowing anything about the genetics I would guess thatone might find more varaition within oranges than between oranges and grapefruit (probably wrong -- feel free to point it out if someone knows one way or the other). Looking at what makes one orange different from another tells you nothing about how different it is from a grapefruit -- they are independent data that can say nothing about each other. The studies presented don't even look at coding regions so sayNOTHING about a potential genetic basis for 'race'. quote: If all you are saying is that classifying people as eitherblack or white is wrong -- I'd agree. The UK police have several racial categories to aid in narrowing down suspects from witness descriptions. If you are saying that there is no genetic basis for a conceptof 'race' I'd say you are wrong -- or at the very least that the supplied evidence+interpretation does not support the contention.
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Mammuthus Member (Idle past 6497 days) Posts: 3085 From: Munich, Germany Joined: |
quote: However, oranges and grapefruit are fruits of completely different species wherease Africans are not a different species from other Homo sapiens (at least I would hope you are not suggesting this). I would therefore not expect the genetic diversity of oranges and grapefruit plants to overlap extensively whereas different populations of humans should have overlapping variation though some traits could reach a high local frequency.
quote: If you can randomly sample two Africans, Chinese, aborigines, whatever and find greater differences between individuals than among populations that are geographically separated i.e. Europeans, then how do you propose to define race genetically in any meaningful way? How can such a concept be in anyway meaninful when it describes a smaller subset of the interindividual variation than exists within a population? It is a genetic concept of race that is not supported by the evidence.Even your Viking example does not stand up to scrutiny. All variable traits show a normal distribution of variants...so are you going to call natural variants of your Viking "race" who are short and have dark hair a different race? How about the !Kung bushmen of Africa...they don't look like the Masai on average..yet another race? I am sure they have some private polymorphisms or microsats that are at different frequencies in the population than fishermen in Hong Kong...does that make them a "race"? My mother is Spanish and my father is a mix of Welsh, German, and Russian...which "race" am I genetically? For that matter, find a "pure" population of anything. If you read basic genetics on the effects of migration on population genetic structure i.e. gene flow...you don't need complete replacement or invasion for homogenization or the spreading of alleles from one population to another and human populations have not been living in complete isolation for a very long time.
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: I wasn't suggesting that Africans were not homo sapien, no. What I was suggesting is that the variability within one populationbears no relation to the differences between that population and another population. quote: First, that's not what the data in the studies posted here shows. The sum of unique differences between 'races' is larger than thesum of common variability for a start. More importantly, the studies presented are looking at non-codingregions -- doesn't that mean that those regions have no phenotypic effect? What relevence then do they have to a concept of 'race'? quote: But the genetic variation present on the Y chromosome WAS sufficientto identify lineages of Viking origin, and to differentiate them from non-Viking lineages. ...so particular 'racial' lineages CAN be identified via geneticanalysis (not external features though -- I mentioned that to suggest that there was some limited relationship between cultural-racial concepts and the possibility of a genetically determined race). quote: Well, yes. I would expect far more 'races' to exist on a continent witha history of geographic & cultural isolation than on one where inter-mingling and inter-breeding has been the order of the day for over 2000 years. quote: Geographically, perhaps, but there are cultural barriers too. The Japanese, for example, didn't even allow foreigners to liveamongst them until, what, the 1700's ... Any 'tribal' cultures would tend to marry among themselves (or perceived related tribes) (e.g. Native americans, Zulu, Bantu, various south american tribal groups, ... probably more). I'll stress at this point that even if there is a genetic basisfor race, I don't see any comparison between them as relevent to the way in which we treat people -- all people are people, but then I would argue that ALL animals deserve to be treated with respect (yes even nylon eating bacteria ). quote: I have no idea whether Spanish, Welsh, German and Russian aredistinct 'races' in themselves (though I suspect Welsh might be). I'm not putting the categories up for approval, I'm saying thatto deny that different populations have genetically determined uniqnesses is not supported by the data presented, and that where those uniquenesses don't overlap they constitute a genetic basis for race. Anectdotal example -- there are certain people of whom one mightsay (and often be correct) 'They look french/welsh/german/american' I'm not just talking about black and white -- and I have noopinion re-superiority -- but if that's why people shy away from suggesting there is a genetic basis for race then scientific interest goes out the window.
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Mammuthus Member (Idle past 6497 days) Posts: 3085 From: Munich, Germany Joined: |
quote: I don't understand this logic at all. So if I want to find out what the genetic diversity is of a species, I should ignore populations that are separated? Which population should I sample then to determine what the variation is for the species? What is representative? and it is not only non-coding DNA that is studied...here is one review Annu Rev Genomics Hum Genet. 2003;4:293-340. Related Articles, Links Patterns of human genetic diversity: implications for human evolutionary history and disease. Tishkoff SA, Verrelli BC. Department of Biology, University of Maryland, College Park, Maryland 20742, USA. st130@umail.umd.edu Since the completion of the human genome sequencing project, the discovery and characterization of human genetic variation is a principal focus for future research. Comparative studies across ethnically diverse human populations and across human and nonhuman primate species is important for reconstructing human evolutionary history and for understanding the genetic basis of human disease. In this review, we summarize data on patterns of human genetic diversity and the evolutionary forces (mutation, genetic drift, migration, and selection) that have shaped these patterns of variation across both human populations and the genome. African population samples typically have higher levels of genetic diversity, a complex population substructure, and low levels of linkage disequilibrium (LD) relative to non-African populations. We discuss these differences and their implications for mapping disease genes and for understanding how population and genomic diversity have been important in the evolution, differentiation, and adaptation of humans. and here is one dealing with genetics and the sociological issues surrounding race Annu Rev Genomics Hum Genet. 2003;4:33-67. Related Articles, Links Race, ancestry, and genes: implications for defining disease risk. Kittles RA, Weiss KM. National Human Genome Center, Howard University, Washington, D.C. 20060, USA. rkittles@howard.edu Geneticists are interested in finding genes associated with disease. Because of widespread health disparities, race is a variable that is often said to be relevant in this context. The idea is that members of a preconceived "race" share common ancestry that may include genetic risk factors. Human variation has been shaped by the long-term processes of population history, and population samples that reflect that history carry statistical information about shared genetic variation or "ancestry." But race is an elusive concept and a term difficult even to define rigorously. Unfortunately, these problems are neither new nor related to recent genetic knowledge. Race is also one of the most politically charged subjects in American life because its associated sociocultural component has notoriously led to categorical treatment that has been misleading and politically misused. There are ways in which the concept of race (whether or not the term is used) can be a legitimate tool in the search for disease-associated genes. But in that context race reflects deeply confounded cultural as well as biological factors, and a careful distinction must be made between race as a statistical risk factor and causal genetic variables. Non-coding genes in any case, are highly useful in determining the genetic relationships both among and within groups with recent common ancestry (as opposed to more slowly evolving coding sequences). Thus, such loci are critical to establishing or refuting race as a valid biological concept.
quote: Why call this a race? I am sure I could distinguish the members of my family from you...does that make us part of a separate race? I have European mitochondrial DNA sequence (from my Spanish mother). My nuclear DNA will be a hodgepodge. Am I a different race from my parents? Particular genetic distinctions can be made between populations without having to resort to race since doing so forces you to basically define any new mutation as a new race (sounds like Syamsu).
quote: I would agree but I would not call this race.Here is the Websters definition...pay attention to the taxanomic defintion of race Main Entry: 3raceFunction: noun Etymology: Middle French, generation, from Old Italian razza Date: 1580 1 : a breeding stock of animals 2 a : a family, tribe, people, or nation belonging to the same stock b : a class or kind of people unified by community of interests, habits, or characteristics 3 a : an actually or potentially interbreeding group within a species; also : a taxonomic category (as a subspecies) representing such a group b : BREED c : a division of mankind possessing traits that are transmissible by descent and sufficient to characterize it as a distinct human type 4 obsolete : inherited temperament or disposition 5 : distinctive flavor, taste, or strength (as a subspecies)...there are no human subspecies. Race is to great a distinction for comparsion of human populations when our closest relative the chimp has overall over 4 fold higher genetic diversity in only a fraction of the population size as the entire human species.
quote: Regarding the japanese...the barriers are leaky as they have a strong genetic connection with the Koreans. J Hum Genet. 1999;44(4):240-5. Related Articles, Links Genetic variations on the Y chromosome in the Japanese population and implications for modern human Y chromosome lineage. Shinka T, Tomita K, Toda T, Kotliarova SE, Lee J, Kuroki Y, Jin DK, Tokunaga K, Nakamura H, Nakahori Y. Department of Public Health, School of Medicine, University of Tokushima, Japan. A polymorphism in the coding sequence of the SRY gene was found by single-strand conformation polymorphism (SSCP) and direct sequencing analysis. The new allele of the SRY gene, which is raised by a C-to-T transition in the 155th codon, was found in 24% of Honshu, 35% of Okinawan, and 51% of Korean males respectively, whereas it was not observed among 16 Caucasian and 18 Negroid males. A haplotype analysis of the Y chromosome was carried out in Japanese, Korean, Caucasian and Negroid populations, using a combination of the polymorphisms in SRY, DXYS5Y, DYS287, and DXYS241Y loci. The results indicated that the Y chromosomes can be classified into seven heplotypes (Ia, Ib, Ic, IIa, IIb, III, IV). However, of these seven, only four (Ia, IIa, III, IV) were observed in the Japanese population. Furthermore, the presumed haplotype C, Y1, YAP, (CA)14, from which haplotype III was probably derived, was not found in any populations in this study. The regional distribution of each haplotype revealed that type III is more frequently observed in Okinawa (16%) and in Korea (21%) than in Honshu (4.4%). The haplotype analysis of the Y chromosome may contribute to the exploration of the origin of Japanese and the relationship between east Asian populations. here is another reference : Am J Hum Genet. 1995 Apr;56(4):951-62. Related Articles, Links Erratum in:Am J Hum Genet 1995 Jun;56(6):1512. Y chromosomal DNA variation and the peopling of Japan. Hammer MF, Horai S. Laboratory of Molecular Systematics and Evolution, University of Arizona, Tucson 85721, USA. Four loci mapping to the nonrecombining portion of the Y chromosome were genotyped in Japanese populations from Okinawa, the southernmost island of Japan; Shizuoka and Aomori on the main island of Honshu; and a small sample of Taiwanese. The Y Alu polymorphic (YAP) element is present in 42% of the Japanese and absent in the Taiwanese, confirming the irregular distribution of this polymorphism in Asia. Data from the four loci were used to determine genetic distances among populations, construct Y chromosome haplotypes, and estimate the degree of genetic diversity in each population and on different Y chromosome haplotypes. Evolutionary analysis of Y haplotypes suggests that polymorphisms at the YAP (DYS287) and DXYS5Y loci originated a single time, whereas restriction patterns at the DYS1 locus and microsatellite alleles at the DYS19 locus arose more than once. Genetic distance analysis indicated that the Okinawans are differentiated from Japanese living on Honshu. The data support the hypotheses that modern Japanese populations have resulted from distinctive genetic contributions involving the ancient Jomon people and Yayoi immigrants from Korea or mainland China, with Okinawans experiencing the least amount of admixture with the Yayoi. It is suggested that YAP+ chromosomes migrated to Japan with the Jomon people > 10,000 years ago and that a large infusion of YAP- chromosomes entered Japan with the Yayoi migration starting 2,300 years ago. Different degrees of genetic diversity carried by these two ancient chromosomal lineages may be explained by the different life-styles (hunter-gatherer versus agriculturalist). of the migrant groups, the size of the founding populations, and the antiquities of the founding events. Regarding how to treat people, I am not arguing about that or accusing you. My issue in this thread is the utility of race as a biological concept and I find it to be completely useless.
quote: My point is that the overlap among populations is enormous. If you look at the genetic diversity distributions of humans they overlap even if some alleles are locally at higher frequency than in other places. Geneticists, evolutionary biologists, or forensics specialists are forced to use population measures of diverstiy as opposed to race measures. Given the implication of race as a much greater genetic distance between groups (subspecies) I do not see any support for this in any study of human genetic diversity and thus find it unhelpful as a concept. I am not claiming that one should ignore differences among groups and this is not the case. Why do you think those studying genetic disease look for isolated populations of people like the Amish? It makes mapping genes easier. But I would not call the Amish a race.
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: The logic is: I have four pairs of identical shapes, each pair has one redand one blue. I separate them into two piles one all red, one all blue. The variation within each group is large since each memberis a different shape. The variation between the groups is small, the only differencebeing the colour. The colour has no useful information about the shape, and theshape has no useful information about the colour. The two measures of 'difference', logically, say nothing about each other. quote: I didn't say none do -- only that the ones presented so far don't. Non-coding regions are not useful in looking at race if theydon't contribute to racial characteristics. That there is a correlation between disease suseptibility and'race' in some sense, suggests there is both a genetic basis for racial distinction and a use for it. quote: You targetted one section of the definition as against my viewof what race is, when everything up to that point from 1-3 fits my view. quote: ...which bears out my hypothesis that such a unique variabilitywould be found amongst the Japanese ... that they interacted with the Koreans and Okinawans is known and shown genetically. How does that detract from a genetic race concept?
quote: It's not the overlap your looking for though -- we're all humanso you know in advance that there is going to be significant overlap ... it's the unique elements that one seeks. There are genetic markers that occur in one 'race' but notin the others. Where we know, historically, that there has been signifcantinteraction we expect more commonality. quote: ...but the definition you cited would place the Amish as aseparate race. Race does not mean sub-species ... not by a long stretch.
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Mammuthus Member (Idle past 6497 days) Posts: 3085 From: Munich, Germany Joined: |
quote: So how is this useful biologically? The color provides no information about any other charactertic of the population so what do I use it for? How about this, Ashkenazi jewish women have a high frequency of BRCA1 mutation and hence a higher than average chance of developing breast cancer. One can, and it has been done, study this group to identify the molecular aspects contributing to breast cancer...all without involving "race" while still ackowledging a characteristic of a specific population and its unique history.
quote: You do realize that genetic mapping involves typing neutral non-coding loci that have nothing to do with actual genes? individual, within group, within and among population differences are not measured by examining non-varying loci. What you are basically stateing here is that because population genetics is based on variable loci that may or may not have to do with a trait one is interested in, such studies are invalid. Population separation, cultural practices etc. have a direct impact on the population genetics of the group and thus non-coding DNA is the first to exhibit such an impact and thus it is the only way to measure differences between groups.
quote: that you define it as "race in some sense" suggests that it is such a fuzzy concept that it is not useful.
quote: I targetted the biological definition as opposed to the cultural since we are talking about whether or not a genetic basis for human race is valid. I exclude definition 1 since there are no breeding stocks of humans. The biological definition refers to a subspecies level distinction among groups for which there is no evidence from human genetics. The second defintion is cultural and I find irrelevant to finding out if there is a biological basis to race...just because someone associates with a group or culture does not mean that their genetics bears out this association.
quote: Because several of the haplotypes common among Japanese are common among other Asian populations. If you had an unmarked sample of blood and typed it genetically you could not say to what "race" it came from. The only differences are the frequency of known alleles as opposed to clear cut lines demarcating alleles that exist in one population and are completely absent in the others like you would expect if there were true distinct "race/subspecies" of humans.
quote: No, we do not know a priori that we are all humans even from morphology. It was not known that forrest elephants in Africa (L.cyclotis) were almost as distinct from savannah elephants (L. africana) as they are from Asian elephants (a different genus) until the genetics was done. If allele frequencies among human groups overlap extensively then regardless of the outliers in the distribution, you cannot subdivide the species into separate races.
quote: It would not as there is not enough to genetically distinguish the Amish from any other human group to warrant a sub-species definition. But since you say race does not mean sub-species...what do you then biologically equate with race?
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: You asked for the logic -- so I boiled it down to the essenceas I see it. The variability within each group has no impact/meaning wrtthe variability between the groups. The colour says nothing about other characteristics -- that's thepoint. It is only useful in distinguishing between groups. They are two different subjects, and cannot be used to informone another. That there is more variability within one population than betweenthat population and another is meaningless. quote: But if I were a GP with this information I might suggest toany member of that group that regular breast checks was imperative (women should do it anyhow, but if you know that a group, by virtue of their lineage, is particularly susceptible one must place that group in a high risk bracket). quote: In relation to race, yes. One looks at data relevant to thequestion, not data that are irrelevent to the question. quote: ...and when used to consider genetic race they show some evidencefor it. Non-overlapping sequences (i.e. ones that occur in one racialgroup and not others) indicate racial separations. quote: Race IS fuzzy, that doesn't mean it doesn't exist. Species isfuzzy too -- are species irrelevent/non-existent? Race, culturally, fits the definitions 1-3 (up to taxonomy), andthis thread was talking about a link between a cultural concept of race and biology. Depends what you mean by 'breeding stock' too ... if youmean managed herds, then no ... if you mean social groups that breed within group then it IS still relevent. Culturally one would say things like 'He's from good stock.'so taking one, literal take on that as a meaning could be mis-leading. quote: You could narrow it down to a limited geographic area though. Such things would be extremely useful in phorensics, for example.
quote: For sub-species, maybe, but that's not my view on race. The genetic difference between different breeds of domestic catmust be quite small -- but you can still deliberately breed for particular coat patterns/colours etc. so the breeds are genetically determined. Why is that different for humans?
quote: Genetically determined traits that are uniquely bounded withina human sub-population.
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NosyNed Member Posts: 9003 From: Canada Joined: |
Genetically determined traits that are uniquely bounded within
Isn't the point that, if you use this definition, there are 1,000's (maybe 100,000's) of races? You could group people by any specific set of genetically determined traits. Hair colour, blood type, propensity for getting a specific cancer, tendancy to higho cholesterol and so on.a human sub-population. Any narrow enough grouping can be useful in the medical arena but a grouping based on the external features we use to specify "race" isn't narrow enough to be useful on an individual basis. As an example:A doctor may be faced with a specific indivdual in her/his office. There are some symptoms presenting. They need to expend money and time on some tests to narrow the probable cause down. They may know that an individual of a particular "race" has a greater chance of having specific genetic propensities. However, this may not be narrow enough to guide the tests in an effective way. More details about the individuals ancestors, blood relavtives may narrow the choices further. Some genetic testing may (and in the future will) narrow them effectively. The point being made here is that "race" is not very useful a tool to make judgements about any individual person. However, it may be that there is enough statisitcaly significance to "race" related propensities to make treating a population based on that ok. That is, an advertising campaign directed at a "race" to encourage them to modify eating habits or to be screened for certain conditions that might be somewhat more prevalent in that group than others. If that is true it is only temporarily useful bacause we don't have all the genetic information we would like.
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sfs Member (Idle past 2555 days) Posts: 464 From: Cambridge, MA USA Joined: |
quote:The figures quoted for within vs between group genetic differences are based on exactly the same measurement -- usually the heterozygosity. So I'd still like to know what you think is different about the comparison within populations and the comparison between populations. quote:If only 1% of the members of the population have the trait, the population can be characterized by the trait. The members of the population cannot be characterized by it. quote:Since no skin color is unique to any of the kind of groups you're talking about, it would seem not to be a unique trait. quote:Refuted by evidence. You cannot decompose human genetic variation into a handful of ideal types. quote:By the definition used earlier in the thread, all northern Europeans are the same race. By yours they're not. More generally, the two definitions are simply different: you mean by race any genetically distinct group, while the earlier poster meant one of a small number of basic genetic types. quote:Leaving aside the fact that "Viking" was actually an occupation, not an ethnic group, do you have any evidence that Vikings thought of non-Scandinavians as of another race? (Other than just assuming that they thought the same way you do.) Humans have a general tendency to dinstinguish their own group from others, but it is not at all obvious to me that they always use racial characteristics to do so.
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: Not really arguing whether or not the existence of race isuseful, only whether there is a genetic basis for it. As far as I can tell from the data posted here, there is. In the case of the areas around Japan there are sequences thatonly occur there, so the 'racial' type of the region could be identified from DNA. Medical usage is only one area of application -- forensic sciencewould be another. Being able to narrow down the suspect list in any way would be useful when only (say) a few strands of hair or other body cells are left at the scene (contamination being an issue of course). I've already said in my posts that I don't believe that thereis anything that means one should treat individuals differently from others -- except individual's actions (e.g. where they are anit-social/illegal).
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Mammuthus Member (Idle past 6497 days) Posts: 3085 From: Munich, Germany Joined: |
quote: So the fact that Africa taken combined demonstrates the greatest genetic diversity (not to mention that most phylogenetic/pop gen studies based on this diversity point to Africa as the source of Homo sapiens) is meaningless? Unless you are channeling Syamsu I do not see how comparison among groups of populations of ONE SPECIES is meaningless. How would you know the relative frequency of anything just looking at one population?
quote: Exactly, however, they are not part of a "race" and if I had assumed they were just of the "jewish race" then I would not have the information about the specific population in the first place and those providing treatment would not be informed. This is another reason why race is a useless concept.
quote: Ok Peter, then by you logic, we can only use genes that are coding and unlikely to vary within the human species or are likely to show converging mutations due to selective constrainst on proteins..there goes your biological race definition since we will all be identical. I guess you also are willing to testify in court that forensic work based on neutral markers for DNA typing are invalid since they are non-coding sequences?
quote: Citations please that indicate that this is true..find me a "racial" sequence that separates north Africans from all other humans on the planet. Good luck, the data do not support you.
quote: You have to make up your mind. Just conflating all the different definintions makes race even more useless. Yes, species are fuzzy so you want to therefore claim there is a precise definition for a concept (race) several orders of magnitude more difficult to reconcile for which there is data that is contradictory to such a proposition.
quote: Good luck catcihg the perpetrator, identifiying the individual, etc. if "narrowing it down" for you means Japan, North and South Korea, parts of China, and Taiwan. Not exactly useful forensically.
quote: Because breeding of domestic cats is by artificial selection that prevents genotypes from interacting with each other to suit a particular taste. Outside of slavery, this has never been the case with humans who experience enough gene flow (and have throughout their history) that alleles you find in Native Americans you will find in South Africans.
quote: Show me an example of a genetically determined trait that is uniquely bound in a human-subpopulation. Actually, show me those traits that overlap with "race" that are genetically determined via citation. I only come across counter examples with very leaky boundaries making the concept useless.
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Peter Member (Idle past 1501 days) Posts: 2161 From: Cambridgeshire, UK. Joined: |
quote: Same measurement, but different comparison. A site with high variability within one group that is different(even non-varying) in another is not directly compared, and yet it is that data that is relevent to the question of race. quote: No they cannot. For a population to be characterised by a traitthen it has to be consistently present. If it is, then all individuals within the population bear the trait ... that many human populations are the result of millenia of interaction between groups brings populations genetically closer together. quote: Which groups were those? What do you mean by skin colour? (i.e. 'we all have skin thathas a colour' is different from consideration of the usual range of skin colours exhibited within a population). I'm NOT hooked on skin colour by the way, any trait will do.
quote: OK ... not entirely convinced by the evidence presented sofar. Perhaps there is some more, or an alternate interpretation that will make this clear. quote: The opinions expressed in this thread seemed to be saying thatthere was no such thing as race at a genetic level. The data presented, as far as I can see, shows the opposite. quote: You perhaps need to check your facts ... I'll check mine too.Viking is the name given to the Danes, Norwegians and Swedes around the 800-1050 AD mark -- it's not what they called themselves -- it's what we call them now. Many Swedish people I have met still think of themselves as Viking -- admittedly most of the times I have heard this expressed is after a heavy night of drinking, so ... What do you mean by 'racial characteristics'? There is more to race than physical appearance -- and that iscaptured culturally by (for example) Zulu's enslaving Bantu and other 'inferior' tribes, or Native American tribes whose name for themselves means 'Human Beings' with the implication that all outside the tribe are not.
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Wounded King Member Posts: 4149 From: Cincinnati, Ohio, USA Joined: |
Peter,
Once again all you are saying is that genetically distinct populations exist, no one is arguing that, if we were to overhaul language usage and make 'race' into a word for a genetically distinct population that would be fine. Unfortunately the word Race is already in common usage and its common usage does not agree with the distinctions you are focusing on. Now you seem to want to reduce things down to tribalism. If fundamental areas of your concept of race are based in nothing more than cultural tribalism why do you expect it to be based on genetics, do you have surprising new evidence on the gene predisposing one to practice slavery.
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sfs Member (Idle past 2555 days) Posts: 464 From: Cambridge, MA USA Joined: |
quote:?? Of course it is. One common procedure: take a pair of chromosomes and compare them in a stretch of sequence. Count the number of differences. Then look at a bunch more pairs. The average number of differences is the measure of genetic diversity. If you do that with chromosomes from the same population, you'll find about one difference every 1200 base pairs. If you do it with chromosomes from different populations, you'll find about one difference every 1300 chromosomes. Another procedure is to find places that are vary between individuals by sequencing chromosomes from both populations. Then compare the allele frequencies at each site for the two populations. Sites that have very different frequencies translate into a large genetic distance, while sites with small differences in frequency mean a small genetic distance. Genetic distances between human populations are generally small.
quote:If that's what you mean by a trait characterizing a population, then there are almost no traits that distinguish races. Almost all traits that are borne by all members of one population are frequent in other populations. quote:Groups that are as closely related as two populations from northwestern Europe, from your Viking example. quote:What did you mean by it? I wasn't the one who brought it up. quote:Which data? I haven't seen any data presented that supports your position, to the extent that I've figured out what your position is. quote:You may call them that, but I certainly don't. Scandinavians of the time who were Vikings called themselves Vikings, but the rest didn't. "Viking" meant (and still means, to anyone who studies the period) a raider or pirate. If you were going off raiding, you were going aviking. quote:I thought we were talking about races as a genetic concept. What does that have to do with these distinctions?
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