posted
are memebers on this board who belong to this haplogroup?where exactly is this haplogroup originated and where is the place with the major population with this haplogroup.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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quote: This ancient haplogroup may have first appeared in North Africa some 45,000 years before present. It is sometimes believed to represent a "second-wave" of expansion out of Africa. However, the location of this lineage's first expansion and rise to dominance appears to have been in India or somewhere close to it within South Asia or the Middle East; all of Haplogroup F's descendant haplogroups also show a pattern of radiation from South Asia (haplogroups H and K) or the Middle East (haplogroups G and IJ).
Several lineages derived from Haplogroup F appear to have migrated into Africa from a homeland in Southwest Asia sometime during prehistory. Y-chromosome haplogroups associated with this hypothetical "Back to Africa" migration include J, K, and R. The occurrence of haplogroups J, K, and R among precolonial populations of Africa is highly correlated with the distribution of languages of the Afro-Asiatic phylum. However, certain subclades of Haplogroup E, which commonly occurs among all modern populations of Africa, are also closely associated with the distribution of Afro-Asiatic languages, both within Africa and in Southwest Asia, which many scholars have taken to support the hypothesis of a Northeast African origin of the Afro-Asiatic languages and subsequent colonization of Southwest Asia by Haplogroup E3b-bearing proto-Semites. Under the scenario of an African origin of Afro-Asiatic languages, the occurrence of Eurasian Y-chromosome haplogroups J, K, and R among Afro-Asiatic-speaking populations of North Africa and East Africa would imply Eurasian immigration or gene flow into northern Africa, accompanied by the loss of the Eurasians' ancestral language and assimilation into the indigenous Afro-Asiatic cultures.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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posted
^ Actually it is still being debated whether haplogroup R represents a back-migration into Africa since the highest frequency occurs in West Africa, specifically Cameroon and the second highest in southern Arabia.
Posts: 26285 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by Djehuti: ^ Actually it is still being debated whether haplogroup R represents a back-migration into Africa since the highest frequency occurs in West Africa, specifically Cameroon and the second highest in southern Arabia.
or it is a mark of colonial presence on these places.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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quote:Originally posted by Djehuti: ^ Actually it is still being debated whether haplogroup R represents a back-migration into Africa since the highest frequency occurs in West Africa, specifically Cameroon and the second highest in southern Arabia.
or it is a mark of colonial presence on these places.
No. This Haplotype predates the existence of Europeans.
Europeans possess R1 derivatives.
Posts: 24 | From: New York | Registered: Sep 2007
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quote: This ancient haplogroup may have first appeared in North Africa some 45,000 years before present. It is sometimes believed to represent a "second-wave" of expansion out of Africa. However, the location of this lineage's first expansion and rise to dominance appears to have been in India or somewhere close to it within South Asia or the Middle East; all of Haplogroup F's descendant haplogroups also show a pattern of radiation from South Asia (haplogroups H and K) or the Middle East (haplogroups G and IJ).
Several lineages derived from Haplogroup F appear to have migrated into Africa from a homeland in Southwest Asia sometime during prehistory. Y-chromosome haplogroups associated with this hypothetical "Back to Africa" migration include J, K, and R. The occurrence of haplogroups J, K, and R among precolonial populations of Africa is highly correlated with the distribution of languages of the Afro-Asiatic phylum. However, certain subclades of Haplogroup E, which commonly occurs among all modern populations of Africa, are also closely associated with the distribution of Afro-Asiatic languages, both within Africa and in Southwest Asia, which many scholars have taken to support the hypothesis of a Northeast African origin of the Afro-Asiatic languages and subsequent colonization of Southwest Asia by Haplogroup E3b-bearing proto-Semites. Under the scenario of an African origin of Afro-Asiatic languages, the occurrence of Eurasian Y-chromosome haplogroups J, K, and R among Afro-Asiatic-speaking populations of North Africa and East Africa would imply Eurasian immigration or gene flow into northern Africa, accompanied by the loss of the Eurasians' ancestral language and assimilation into the indigenous Afro-Asiatic cultures.
It has already been established through linguistics, which has more direct bearing, that Afrisan languages originated solely within Africa, which has the greatest diversity of such languages.
And also, why would R have to be associated with colonialism in your (apparently sick) mind?
Posts: 140 | From: USA | Registered: Jan 2006
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posted
^ This issue was dicussed numerous times before. One of the biggest problems in human genetics is distinguishing non-African lineages from African lineages since all non-Africans descend from Africans. Until more comprehensive data is taken about a particular haplogroup such as the case of the very ancient R1*, we won't be sure.
Posts: 26285 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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posted
Initially intended for parent and spin-off topics that both got highjacked with irrelevancies, the following remains pertinent to the issue of R1* amongst others:
Recently the question of K2-M70 geographical origin was raised, and someone suggested that it was "Asian". It may very well be that, but it may also not be unreasonable to say that this is should be read as "tentatively speaking", until all possible technicalities of the K-M9 superhaplogroup has been examined. It is also related to another issue raised about the genetic distant between *original* paternal J haplogroup carriers and Africans, in that, both are direct descendants of the F-M89 clade.
When I say that the use of the terms 'tentatively speaking' must be promoted - pending elaborate examination, I do so, perhaps because many [though not exclusively of course] of these lineages are only found in the downstream states in the various cases studied thus far. K-M9 happens to be one of those direct descendants of F-M89, a lineage representing an ancestor who could well have been African- who knows, pending specifics to that end?
In many cases, origins for downstream lineages are inferred from things like:
*The frequency of haplotypes and the diversity of these haplotypes of a superhaplogroup in a region.
*The micro satellite diversity of haplotypes, i.e. their clusters.
*The frequency and distribution pattern of undifferentiated paraphyletic haplogroup of a designated superhaplogroup.
*Supplementary material from other genealogical evidence outside of Y chromosome and mtDNA, and where necessary, linguistic and archaeological evidence consideration. Looking at an exemplary case that relates to the topic at hand, in that it examines K-M9 and its derivatives in certain populations, we have:
How can the presence of Group IX chromosomes at considerable frequency in Cameroon be explained? A priori, we can envision three possibilities.
*First, group IX chromosomes in Cameroon are due to rather recent male gene flow from Europe or the Near East.
*Second, the entire M9 superclade (haplogroups VII-X] has an African origin.
*Third, group IX chromosomes in Cameroon represent a footprint of a male back migration from Asia to Africa.
The 'parsimonious' deductions of the above, were deemed the following respectively:
*The first scenario seems to be very unlikely, because only derived haplotypes, carrying the M269 or M17/SRY10831 mutations, have been detected in western Eurasia.
*The second hypothesis, an African origin of the M9 superclade that includes haplotype 117, would imply a subsequent impressive extinction of derivative lineages in sub-Saharan Africa, since no other haplotypes carrying the M9 mutation (haplogroups VII-X) have been observed in this region (the only exception being represented by a few haplotype 109 chromosomes found in the Fulbe from Cameroon).
*The last scenario, that of a back migration from Asia to Africa, currently appears to be by far the most plausible. This is because most of the M9 haplotypes (the majority of group VII and VIII lineages, as well as some group IX and X lineages reported by Underhill et al. 2000) have been observed only in Asia. Moreover, this possibility appears to be further supported by the recent finding of the UTY2+/M173 - intermediate haplotype (Karafet et al. 2001) in central and northeastern Asia (the UTY2 marker in the study by Karafet et al. 2001 corresponds to M207 in the present study).
Cruciani et al. 2002 deduction in the first scenario makes absolute sense, and the statement speaks for itself without further interpretation.
The second scenario follow up doesn't necessarily make as much sense as the first deduction, since it is not necessary for Africa to have harbored *all * the downstream mutations for M9, for its probably origin to have occurred here. Indeed, the author even acknowledge M9 chromosomes - outside of the R-M207 derivatives - in Cameroonian samples, even though they note this [K2-M70 derivative] as an 'exception' in their case study. They may well be relating to the idea that K2 is the only other derivative they're able to detect in the sub-Saharan region(s) in question. At any rate, K2 is found in a number of other sub-Saharan African populations, as is the case with sub-Saharan east Africa.
The follow up of the last scenario, while possible, doesn't mean that this was so either; again, the rationale here is that Africa necessarily needs to have a very high diversity of M9 downstream mutations so as to be able to be the probable place of origin of the ancestral M9 clade. They figure that relative less diversity in downstream mutations of M9 superhaplogroup in Africa could be accounted for by a series of extinctions somewhere down the road, but a better explanation would be back-migration from a region where there is more haplotype diversity of the superhaplogroup.
The authors don't necessarily appear to be factoring in the possibility that lineages could remain relatively restrained in their diversity in an initially small-sized population which didn't undergo much expansion for a good deal of time until at a certain point down the road, and then began to expand for whatever reason(s). It is after a period of such probable population bottleneck, followed by considerable expansion, that the survivability rate of new downstream mutations increases and expands. So in one small-sized population, a lineage could start out to be rather limited in its diversity, and then start to become more diverse at a later time, as a product of demographic expansions. Whereas given a scenario whereby another population diverged from such small-sized population at an early timeframe, let's say at a time when the diversity of a particular lineage was minimal, and then migrated into another region [founder effect] and thereof expanded relatively more rapidly than its sibling population [at the other location - nearer to the point of origin], it is likey that this divergent group will sport more clade diversity over time than the sibling population which expanded relatively later or slower; the expansion timeframe of subclades in the former will likely reflect such earlier expansion than the expansion timeframe of those in the latter, but it'll probably fall short of telling us that the former is the ancestral population over the latter - if not give a false impression of that, and why should it...when considering the probable scenario of the populations diverging early from a common recent ancestral group. It may be worth taking note that Cruciani et al. also invoke the scenario just mentioned - albeit in one alternative, while taking into account the antiquity of the lineages in question:
It is quite reasonable to hypothesize that an ancient Asian gene pool was the source of both the European (haplotype 117b) and Cameroonian (haplotype 117) M173 chromosomes. **The fact that haplotype 117 is rare or absent in Asia (P.A.U; unpublished data) or the Middle East (present study), suggests that a large portion of its micro satellite diversity in Cameroon accumulated within the African continent after the proposed back-migration event, probably as a consequence of a population migration...
The absense in northern Cameroon of Y haplotypes affiliated with the decolonization of Europe following the Last Glacial Maximum, as well as the subsequent Neolithic transition (Semino et al. 2000), is consistent with this interpretation
^It is of interest, that the authors here envision the scenario I mentioned above, but in a direction whereby a lineage in an initially less diverse population in Asia migrated into Africa, and thereby attained a certain level of micro satellite diversity in the relatively rare M9-derived R-M207 chromosomes in Cameroon. They favored this over the other plausible scenario of the event occurring in the opposite direction, that is - appearing first in a small-sized African population, whereby a section of the population diverged and located into Asia via the Nile Valley corridor, but for some reason began to expand more rapidly than its counterparts which gave rise to contemporary descendants who now live in Egypt and Cameroon. They decided to do this, as noted above, mainly on the account of more haplotype diversity of the M9 superhaplogroup outside of Africa. A move that seems to indicate that the authors acknowledge the lack of air-tightness of their preferred interpretation, may well be this:
Interestingly, a frequency of 13% has been previously reported in an Egyptian sample for a group of chromosomes defined as haplotype 1 C (Scozzari et al. 1999) and closely related to the M173 chromosomes. Unfortunately, this sample was not available for the present study.
Although we cannot define more precisely the haplotype of the Egyptian 1C Y chromosomes, it is worth noting that four of six of these chromosomes showed dinucleotide micro satellite haplotypes that matched or were one step neighbors of the M173 chromosomes found in Cameroon.
These rare M173 chromosomes in Egypt [and Cameroon] had obviously been noted in other studies, aside from the present study and the referenced study of Scozzari et al. 1999, namely:
K2‐M70 chromosomes are detected in Tanzania (3.8%), Egypt (8.2%), and Oman (8.3%). M173 chromosomes (group R) are observed in the Bantu of southern Cameroon (14.3%), Oman (10.7%), Egypt (6.8%), and the Hutu (1.4%). Whereas the R1*‐M173 undifferentiated lineage is present in all four populations, the two downstream mutations, M17 and M269, are confined to Egypt and Oman. - Luis et al. 2004
It's of note, in one of the tables presented, that 1 out of 101 Omani individuals carried R*-M173, while 2 of Egyptian 101 individuals carried the lineage, with 14 individuals out of 99 or so Cameroonians and 1 out of about 99 Hutu individuals.
Thus, R*-M173 shows up in three mainland African groups. K2 is also noted in other populations besides Egypt and Cameroon, as noted earlier.
Don't know the precise extent of genetic *resolution* achieved by them, but from Flores et al. 2005, we are told:
Intrapopulation differentiation in Jordan
As Bedouin tribes had an important role in the colonization of southeast Jordan, it could be that the haplography composition of the Dead Sea reflected genetic affinities to them, but that is not the case. The most striking characteristic of the Dead Sea sample is the high prevalence of R1*-M173 lineages (40%), contrasting with the lack of them and of its derivatives R1b3-N269 in Bedouin from Nebel et al. (2001) and its low frequencies in Amman. It is worth mentioning that until now, similar frequencies for R1*-M173 have only been found in northern Cameroon (Cruciani et al. 2002). The possibility that the Dead Sea and Cameroon are isolated remnants of a past broad human expansion deserves future studies.
Interestingly, when the molecular heterogeneity of the G6PD locus was compared between the Amman and the Dead Sea samples, a lower number of different variants and a higher incidence of the African G6PD-A allele was detected in the latter (Karadsheh, personal communication). Another singularity of the Dead Sea is its high frequency (31%) of E3b3a-M34, a derivative of the E3b3-M123 that is only found in 7% Bedouins (Cruciani et al. 2004). Until now, the highest frequencies for this marker (23.5%) had been found in Ethiopians from Amhara (Cruciani et al. 2004). On the contrary, most Bedouin chromosomes (63%) belong to the haplography J1-M267 (Semino et al. 2004) compared with 9% in the Dead Sea. All these evidences point to the Dead Sea as an isolated region perhaps with past ties to sub-Saharan and eastern Africa.
Strong drift and/or founder effects might be responsible for its anomalous haplogroup frequencies.
If I didn't know any better, I'd say that Flores et al. are suggesting here the possibility, that R1*-M173 chromosomes may have arrived into the said region in Jordan from Africa, and it seems that the G6PD-A allele on the X-chromosome, deemed to be under selective pressure of malarial resistance, had been seized on as a possible support for this scenario. High frequencies of rare R1* chromosomes in Cameroon had been particularly noted to this end as well, it seems.
quote:Originally posted by Djehuti: ^ Actually it is still being debated whether haplogroup R represents a back-migration into Africa since the highest frequency occurs in West Africa, specifically Cameroon and the second highest in southern Arabia.
or it is a mark of colonial presence on these places.
No. This Haplotype predates the existence of Europeans.
Europeans possess R1 derivatives.
so you mean haplogroup R*, I thought Europeans also beared that haplogroup, but I see I'm mistaken,thanks. Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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quote: This ancient haplogroup may have first appeared in North Africa some 45,000 years before present. It is sometimes believed to represent a "second-wave" of expansion out of Africa. However, the location of this lineage's first expansion and rise to dominance appears to have been in India or somewhere close to it within South Asia or the Middle East; all of Haplogroup F's descendant haplogroups also show a pattern of radiation from South Asia (haplogroups H and K) or the Middle East (haplogroups G and IJ).
Several lineages derived from Haplogroup F appear to have migrated into Africa from a homeland in Southwest Asia sometime during prehistory. Y-chromosome haplogroups associated with this hypothetical "Back to Africa" migration include J, K, and R. The occurrence of haplogroups J, K, and R among precolonial populations of Africa is highly correlated with the distribution of languages of the Afro-Asiatic phylum. However, certain subclades of Haplogroup E, which commonly occurs among all modern populations of Africa, are also closely associated with the distribution of Afro-Asiatic languages, both within Africa and in Southwest Asia, which many scholars have taken to support the hypothesis of a Northeast African origin of the Afro-Asiatic languages and subsequent colonization of Southwest Asia by Haplogroup E3b-bearing proto-Semites. Under the scenario of an African origin of Afro-Asiatic languages, the occurrence of Eurasian Y-chromosome haplogroups J, K, and R among Afro-Asiatic-speaking populations of North Africa and East Africa would imply Eurasian immigration or gene flow into northern Africa, accompanied by the loss of the Eurasians' ancestral language and assimilation into the indigenous Afro-Asiatic cultures.
It has already been established through linguistics, which has more direct bearing, that Afrisan languages originated solely within Africa, which has the greatest diversity of such languages.
And also, why would R have to be associated with colonialism in your (apparently sick) mind?
Because Europeans bear Haplogroup R,I thought they were.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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