quote:In human genetics, Haplogroup R (M207) is a Y-chromosome haplogroup.
Haplogroup R is a subgroup of haplogroup P, associated with the M207 change. It is believed to have occurred somewhere in North West Asia between 30,000 and 35,000 years ago.
The majority of members of haplogroup R belong to the sub-haplogroup R1, defined by marker M173, with its main subgroups R1a1 (M17) and R1b (M343). Less common is the alternate subgroup R2 (M124), found only in Indian, Iranian, and central Asian populations. Individuals with neither of these mutations are categorised as belonging to group R*.
Haplogroup R1 is very common throughout Europe and western Eurasia. It is believed to be associated with the initial spread into Eurasia following the last glacial maximum.
Haplogroup R, for instance, is identified by a y chromosome mutation known as M173. Roughly 70 percent of English men have this lineage, 95 percent of Spanish men, and 95 percent of Irish men.
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posted
This was posted in another thread by Mystery Solver.
An excerpt from Luis et al. 2004...
“The Oman collection in the present study is the only population outside of Africa in which R1*-M173 has been found. Up until now, these undifferentiated lineages have been detected only in Egypt and in some Central and West African populations (Cruciani et al. 2002; present study). It is plausible that the African and Omani R1*-M173 chromosomes may be relics of an ancient back migration from Asia to Africa, which may have been a southern branch of the Upper Paleolithic westward expansion of this clade after its emergence in northern Asia ∼30 ky ago (Underhill et al. 2001b). The antiquity of the M173 backflow is implied by the total lack in sub-Saharan Africa of downstream mutations associated with the post–Last Glacial Maximum (LGM) reinhabitation of Eurasia (R1a1-M17 and R1b-M269) (Semino et al. 2000) or, later, with the Neolithic expansion (J-12f2 and G-M201) (Hammer et al. 2000; Semino et al. 2000; King and Underhill 2002; Cinniog˘ lu et al. 2004).
Egypt is the only African population that is known to harbor all three M173 subtypes (R1b-M269, R1*-M173, and R1a1-M17). This unique status is most likely due to Egypt’s strategic location and its long history of interaction with Eurasia. Oman, like Egypt, also exhibits all three M173 haplogroups. The relatively high frequency of R1a1-M17 (9%) may result from the post-LGM expansion associated with this mutation. The ex-pansion estimates of this haplogroup (11.4–3.4 ky; see table 3) support this hypothesis. The above data strongly suggest that the Levantine corridor was, by far, more important than the Horn of Africa passage in the original African dispersal of undifferentiated M173 chromosomes as well as the more recent introduction into Africa of its derivatives, since the M173 mutation is nearly absent in East, Central, and South African collections, except for a 1% frequency in both the Ethiopian (Underhill et al. 2000) and the Hutu assemblages.” - Luis et al. 2004
Posts: 24 | From: New York | Registered: Sep 2007
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quote:Originally posted by fivebifive: I'm assuming that this is reference to the Y chromosome Haplogroup F thread.
First off, what is your source? Always site your source.
I have not seen any study to date that state that R1* is a European haplotype.
The genographic project classify the haplogroup as an Indo-European one.
I think you're missing the point. R1* is not found amongst Europeans, therefore it is not a European lineage. Europeans possess R1 derivatives R1a and R1b. The R clade is Eurasian in origin.
You claimed that R1 underived in Cameroon was due to colonization ie European colonization but yet Europeans don't possess said haplotype and the time depth for it precedes the existance of Europeans, therefore it cannot come from them.
Hope that's clear.
Posts: 24 | From: New York | Registered: Sep 2007
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quote:Originally posted by fivebifive: I think you're missing the point. R1* is not found amongst Europeans, therefore it is not a European lineage. Europeans possess R1 derivatives R1a and R1b. The R clade is Eurasian in origin.
You claimed that R1 underived in Cameroon was due to colonization ie European colonization but yet Europeans don't possess said haplotype and the time depth for it precedes the existance of Europeans, therefore it cannot come from them.
Hope that's clear. [/QB]
Yes, it is Eurasian,perhaps I confused it with it's derivatives.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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quote:In human genetics, Haplogroup R (M207) is a Y-chromosome haplogroup.
Haplogroup R is a subgroup of haplogroup P, associated with the M207 change. It is believed to have occurred somewhere in North West Asia between 30,000 and 35,000 years ago.
The majority of members of haplogroup R belong to the sub-haplogroup R1, defined by marker M173, with its main subgroups R1a1 (M17) and R1b (M343). Less common is the alternate subgroup R2 (M124), found only in Indian, Iranian, and central Asian populations. Individuals with neither of these mutations are categorised as belonging to group R*.
Haplogroup R1 is very common throughout Europe and western Eurasia. It is believed to be associated with the initial spread into Eurasia following the last glacial maximum.
Haplogroup R, for instance, is identified by a y chromosome mutation known as M173. Roughly 70 percent of English men have this lineage, 95 percent of Spanish men, and 95 percent of Irish men.
This haplogroup could not have appeared in Eurasian at this time the archaeological evidence shows that most of the homo sapien sapiens were CroMagnon man who carried the N haplogroup.
posted
^ Dr. Winters. Respectfully please at least try to listen to those of us who are trying to be of assistence with genetics.
The haplotype "N" you are refering to is maternal.
Haplotype R is paternal.
Your take on this is thefore rooted in a complete and fundamental misunderstanding.
As for the parent post....
quote:Haplogroup R1 is very common throughout Europe and western Eurasia.
This is also WRONG.
R1 is found in primarily in Central Africa [cameroon], and in much lesser frequency, in Egypt and the Levantine.
There is NONE in Europe.
It is not clear where it originates. The Levantine is certainly a good prospect, however it could also originate in NorthEast Africa, or in Central Africa, where it is most common.
Posts: 15202 | Registered: Jun 2004
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posted
I believe that R1 did develop in Africa. The fact remains that there is no evidence that it existed in Eurasia at this time. Any opinions on the existence of this haplotype is pure speculation, and based on statistical models which to date have not been supported by any hard evidence.
.
-------------------- C. A. Winters Posts: 13012 | From: Chicago | Registered: Jan 2006
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quote:Originally posted by rasol: ^ Dr. Winters. Respectfully please at least try to listen to those of us who are trying to be of assistence with genetics.
The haplotype "N" you are refering to is maternal.
Haplotype R is paternal.
Your take on this is thefore rooted in a complete and fundamental misunderstanding.
As for the parent post....
quote:Haplogroup R1 is very common throughout Europe and western Eurasia.
This is also WRONG.
R1 is found in primarily in Central Africa [cameroon], and in much lesser frequency, in Egypt and the Levantine.
There is NONE in Europe.
It is not clear where it originates. The Levantine is certainly a good prospect, however it could also originate in NorthEast Africa, or in Central Africa, where it is most common.
Then a new investigation should be made.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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posted
^ Science is and ongoing process - when the early speculations about the Asian origin of R1 were made, it was not known that the underived lineage existed in substantial degree in any population.
At present the lineage is most heavily found in Cameroon.
Ancient back-migration theories are a slipperly slope of back-peddling.
The futher you go back in time - the closer you are to the original African-Exodus. Evemtually you moot the explanitory power of back-migration theory.
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quote:Originally posted by rasol: Ancient back-migration theories are a slipperly slope of back-peddling.
The futher you go back in time - the closer you are to the original African-Exodus. Evemtually you moot the explanitory power of back-migration theory.
Evergreen Writes:
This is exactly right. In fact the earliest Europeans were both tropically adapted and cranially akin to indigenous Sub-Saharan Africans.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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quote:Originally posted by rasol: ^ Science is and ongoing process - when the early speculations about the Asian origin of R1 were made, it was not known that the underived lineage existed in substantial degree in any population.
At present the lineage is most heavily found in Cameroon.
Ancient back-migration theories are a slipperly slope of back-peddling.
The futher you go back in time - the closer you are to the original African-Exodus. Evemtually you moot the explanitory power of back-migration theory.
Exactly. This point can't be made enough.
Posts: 26246 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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quote:Originally posted by prmiddleeastern: it is haplogroup R* also found in Africa?
None that i'm aware of has been found to date.
Then where can R* be found?
Evergreen Writes:
* Cameroon
* Nigeria
* Egypt
* Jordan
Do you have a source?
I wasn't aware that R underived was found in those places.
Evergreen Writes:
Of course I have a source. But we have covered this many times on this forum. Please use the search function as a starting point.
Posts: 2007 | From: Washington State | Registered: Oct 2006
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posted
^Indeed, we know about R1* being found in Cameroonian, Egyptian, Jordanian, Omani, Hutu samples, but that of R* has yet to come to my attention.
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.
but what i don't understand is that according to this map, there are haplogroup R individuals in deep Africa, but there is not significative amount on the rest of Africa,but only on a few populations in North and Central-West and east africa.
Posts: 1106 | From: Puerto Rico | Registered: Aug 2007
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but what i don't understand is that according to this map, there are haplogroup R individuals in deep Africa, but there is not significative amount on the rest of Africa,but only on a few populations in North and Central-West and east africa.
^ That's because R1 underived [which is actually not specified particularly in this map] is and ancient and rare haplotype.
It's not the only rare haplotype which restricted and isolated.
For example E3 - the direct paternal ancestor of E3a and E3b is found in Ethiopia, and Senegal, but is not common anywhere else.
E2 and E1 also have highly restricted and patchy distribution ranges.
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posted
^ Something else not understood about underived R1 in central Africa.
Why is the haplotype -still underived- when R1 in Eurasia is only found in the way of downlevel R1a and R1b?
Well this because R1 was defined 1st in the downlevel Eurasian populations.
You could theoretically identify unique markers on the R1 Y chromosome of Africans as well.
Perhaps R1"XYZ" and so forth.
What was discovered in Africa was and R1 chromosome that did not have the specific markers that identify R1a and R1b, these means the marker could not have been introduced into Africa via downlevel Eurasian populations.
It either originated in Africa then left Africa for the Levant, and then split into R1a and R1b in central Asia......
or it left Africa as and upstream M89 lineage, split into R1 M170 in the levant, then came back to Africa as and African R1, and went into Eurasia as split into Eurasian R1a and R1b.
I don't know which is the case, but supercar's post showing the other African genetic signatures in the only non African populaton bearing this haplotype seems to me to be powerfully suggestive of and African origin.
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posted
^ That's the impression I get also-- that R1* is African in origin. So what about original R*??
Posts: 26246 | From: Atlanta, Georgia, USA | Registered: Feb 2005
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but what i don't understand is that according to this map, there are haplogroup R individuals in deep Africa, but there is not significative amount on the rest of Africa,but only on a few populations in North and Central-West and east africa.
^ That's because R1 underived [which is actually not specified particularly in this map] is and ancient and rare haplotype.
It's not the only rare haplotype which restricted and isolated.
For example E3 - the direct paternal ancestor of E3a and E3b is found in Ethiopia, and Senegal, but is not common anywhere else.
E2 and E1 also have highly restricted and patchy distribution ranges.
Thank you for the info about R1, but what about R*, where it is originated,and also thaksn for the information about E* E1, E2 and E3*.
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