Jump to content

Talk:Haplogroup CT/Archive 1

Page contents not supported in other languages.
From Wikipedia, the free encyclopedia
Archive 1

Untitled

The mutation is believed to have occurred 31 to 55 thousand years before present within North East Africa.

Haplogroup C (Y-DNA):

Haplogroup C seems to have come into existence shortly after M168 was introduced, probably at least 60,000 years before present.

How Can C be older than CR?

The age "31 to 55 thousand years" is certainly too young. The mutation actually very probably occured 60-70 000 years ago in an East African group of Homo sapiens that was located in a local "refugial" area. The period between 71-60 000 years ago was extremely cold and dry, which also suggest that modern people didn't leave Africa earlier than 60 000 years ago. Centrum9982.100.61.114 17:22, 29 October 2007 (UTC)

Inaccurate Map

The map shows a DE that originated in the Middle East, and a back-migration of Haplogroup E into Africa. What is the evidence that DE did not originate in Africa, like A,B,C and E? Remember that D is the haplogroup of the Andamamese and Negritos of Asia. — Preceding unsigned comment added by 83.84.79.63 (talk) 17:27, 8 September 2015 (UTC)

I agree. The idea of a back-migration of Haplogroup E from Asia has long ago been debunked. There seems to be some kind of effort to re-establish the theory that E came from D in Asia, rather than that DE gave rise to D and E in Africa. Same thing is going on at the [haplogroup page]. Also read their talk page. MrSativa (talk) 00:07, 23 October 2016 (UTC)

Asian origin for DE has not been debunked? It is definitely still a viable theory for the origin of Haplogroup DE. — Preceding unsigned comment added by 73.22.96.109 (talk) 07:27, 12 July 2019 (UTC)

Updates

I've gone ahead and changed a few things based on the ISOGG pages, which are already listed as a reference. Ardric47 (talk) 08:58, 11 May 2008 (UTC)

There needs to be another update of this page. CT has been renamed by ISOGG to Haplogroup CF. --Brout8 (talk) 17:01, 5 October 2009 (UTC)
Have they given any indication about their source for this? I do see their webpage as an authority, and it is frequently cited, but it would be good to know that they are not the only one.--Andrew Lancaster (talk) 18:28, 5 October 2009 (UTC)
What does that mean?--Andrew Lancaster (talk) 19:02, 13 September 2010 (UTC)

Merger proposal

I propose that Haplogroup_CT be merged into Y-Chromosome Human_Y-chromosome_DNA_haplogroups. I think that the content in the Haplogroup_CT article can easily be explained in the context of Y-Chromosome Haplogroups, and the Haplogroups article is of a reasonable size that the merging of this article will not cause any problems as far as article size or undue weight is concerned. RebekahThorn (talk) 18:29, 3 April 2013 (UTC)

As a general principle I agree that not every node of a phylogeny needs an article. I also agree that for this particular article to have a long term future, it eventually needs to have some substance in it which goes beyond what can be read in the articles for the parent and child clades. And it does not have that yet. But these are just general principles. I hope it helps discussion, but I do not have a strong position upon how likely it is that this article is a placeholder for future substance.--Andrew Lancaster (talk) 19:28, 4 April 2013 (UTC)
Yet, would not holding this article open year after year waiting for the reviewed publication that will give it substance be putting speculation and wishes ahead of published scientific facts? I think that by pulling these deep ancestral stubs together in one article we could achieve a strong article today. Of course, should those publications ever come to print, I would fully support recreating this article. --RebekahThorn (talk) 22:34, 10 April 2013 (UTC)
  • Oppose strongly for the following reasons at least:
  1. Wikipedia is not paper.
  2. Separate articles on macrohaplogroups enable lay readers to easily understand lines of descent, through one mouse click/screen touch.
  3. We should avoid any tendency towards presentism. Each "new" macrohaplogroup actually represents a significant event in human prehistory and genealogy. Knowledge about macrohaplogroups will grow (and in some cases basal members may even be found – if they haven't been already).
    Grant | Talk

Regarding Origin of CT

@73.22.96.109: Recently you seem to have cited several sources as supporting a Eurasian origin hypothesis for haplogroup CT in the infobox. However, none of the sources seem to make the argument for a Eurasian origin of haplogroup CT. I removed the new additions with an explanation in the article's "History" notes, which are reproduced here (below):

Regarding the Wang et al. source, Wang does not seem to posit a Eurasian origin for CT. Wang describes CT as the "out-of-Africa superhaplogroup CT" (on page 3 below) implying an African origin (in keeping with its label from other authors as the "Out of Africa Adam" or "Eurasian Adam" lineage, i.e. associated with the main African group that left Africa and was ancestral to modern Eurasians). See: https://www.biorxiv.org/content/biorxiv/early/2014/05/03/004705.full.pdf Also, the Wang et al. source is a non-peer-reviewed preprint and thus not acceptable according to Wikipedia's rules regarding reliable sources.

Wei et al. also does not seem to argue for CT having a Eurasian origin. See: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3820021/

To make inferences/conculsions from a source that are not present in the source itself would violate Wikipedia's rules regarding "POV" (See:WP:POV) and "Original Research"(See:WP:NOR).

Please avoid POV additions. Thank you Skllagyook (talk) 07:42, 12 July 2019 (UTC)

@Skllagyook

None of the sources that was listed including (PA Underhill) stated that Haplogroup CT originated in Africa, instead it simply states,

"The remainder of the deep structure of the phylogeny is characterized by three subclusters that coalesce at the root of the CR-M168 node, which represents the majority of African varieties as well as all the non-African haplogroups (114). This level of structuring of continental pools of Y chromosomes (K = 2) includes: (i ) the shared presence of haplogroup DE chromosomes in Africa and Asia; (ii ) the non-African haplogroup C, which is widely distributed in East Asia, Oceania, and North America; and (iii ) a global distribution of another non-African cluster, haplogroup F-M89, with its most prolific daughter-group haplogroup K."

None of the sources mentioned seem to clarify that CT specifically originated from Africa or Eurasia. — Preceding unsigned comment added by 73.22.96.109 (talk) 07:52, 12 July 2019 (UTC)

@73.22.96.109: That is not the case. Underhill et al. (2007) does mention an African origin for haplogroup CT (sometimes also termed "CDF" or "CDEF"—i.e. the common ancestor of haplogroups DE and CF), also called M168, which he finds to be most likely (figure 8, scenario D) on page 555.
And on page 554 (describing scenario d of figure 8):
"Using the principle of phylogeographic parsimony, which minimizes the number of inferred migrations and the fact that the deepest clades (A and B) occur solely in Africans, an African origin of haplogroup CDEF-M168, M294 node was proposed (39, 116) and supported in a survey of over 12,000 Asian men" "...These results hold up the phylogenetic scenario shown in Figure 8d, which is consistent with two independent founder types, D and CF, evolving outside Africa..."
Underhill also writes on page 556:
"...both the refutation of the option shown in Figure 8b and the apparent absence of deep-rooted haplogroups for either CF or D chromosomes in Africa bolsters the model that haplogroup CF and DE molecular ancestors [i.e. CT/CDF, the common ancestor of CF and DE] first evolved inside Africa and subsequently contributed as Y chromosome founders to pioneering migrations that successfully colonized Asia."
See: "Use of Y Chromosome and Mitochondrial DNA Population Structure in Tracing Human Migrations" (by Underhill and Kivisild 2007)
https://pdfs.semanticscholar.org/f4ee/6bfac21f39ac51fc306ba3100c2ebd2ee61a.pdf


Johnson also mentions Africa as the most likely place of origin for haplogroup CT/"Eurasian Adam" (a.k.a. y mutation M168):
"It is quite possible the Eurasian Adam (M168) could have met Eurasian Eve...The estimate of their dates overlap (around fifty thousand years ago) and they both probably lived in Northeast Africa. Yes, Africa..." (page 100)
https://books.google.com/books?id=bmHe2MU4pycC&pg=PA100&lpg=PA100#v=onepage&q&f=false


Karafet et al. 2008 also imply that CT is of African origin in discussing the discovery of the "supercluster "p143" (also known as CF, a subclade of CT), which is suggested to have been "carried out of Africa very early" as part of the Out-of-Africa migration of the ancestors of modern non-African humans), which is to say that (according to Karafert et al.) CF split from CT while in Africa and then afterward was carried out of Africa into Eurasia:
"The deepest polychotomy in the YCC tree has now been resolved by virtue of a new binary marker, P143, which unites haplogroups C and FT (Fig. 1). This supercluster contains lineages that are not typically found in sub-Saharan Africa, suggesting that the ancestral C-FR chromosome may have been carried out of Africa very early in the modern human diaspora..." (Karafet et al. Page 2)
https://genome.cshlp.org/content/early/2008/04/02/gr.7172008.full.pdf+html
Another version of the Karafet et al. 2008 paper (link below) refers in the same passage/section to "the ancestral "C-FT chromosome" instead of "C-FR", meaning that perhaps it was CT that left Africa with CF diverging from it in Eurasia (and with CF's sibling DE either diverging in Africa from the CT that had remained there/in Africa with some DE leaving Africa later, or DE diverging in Eurasia — that is currently uncertain/unknown, though the most recent paper suggests/proposes an African origin for DE as well); but either way CT would be of African origin, whether it (some of it) itself left Africa (with CF then diverging from it in Eurasia) or whether CF split from it while in Africa and then entered Eurasia.
https://genome.cshlp.org/content/18/5/830.full
More recently (from two papers, from 2015 and 2019 respectively), the likely divergence date for haplogroup CT has been pushed back to ca. 100,000 or ca. 101,000 years ago (which is, according to most researchers, significantly before the Out-of-Africa migration of the ancestors of modern Eurasians).
See:
(study at first two links below - second link, see Figs S9 and S13, is supplemental material from the study in first link - refers to CT/"M168" (common ancestor of D/E and C/F) as "DT", dating it to ca. 100,000 years ago and stating that it is of African origin - also, Fig 1 at first link)
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4381518/
https://genome.cshlp.org/content/suppl/2015/02/18/gr.186684.114.DC1/Supplemental_Figures.pdf
and (Table S2 of the Supplemental Material from source below, dates CT's divergence to ca. 101,000 years ago, similarly to the above paper):
https://doi.org/10.1534%2Fgenetics.119.302368
Skllagyook (talk) 08:10, 12 July 2019 (UTC)

Low coverage results

Editors often list low coverage ancient DNA samples that were determined to be CT (or likewise on other pages, e.g. BT, IJK) on pages like this. This is misleading. Unless the sample has actually tested negative for downstream branches, there is nothing special about it. For instance, of 5 male Natufians studied by Laziridis et al, 3 were found to have E1b1, and 2 were CT - with no branches known to be negative. That only means they weren't A or B (or Neanderthal); it does not stop them from also having been E1b1, or anything else you might expect to find (H2, T, J, G, etc). Sure, in principle, they *could* carry some exotic CT paragroup - but their being listed as CT provides absolutely no evidence for that. Any random untested skeleton *could* carry some exotic CT paragroup, with equal probability.

If a sample was found to actually have the paragroup CT*(C, D, E, F), that would be notable. Otherwise, having a plain CT sample is only interesting if any branch of CT it might belong to would likewise be interesting in that context. For instance, if you found CT in South Africa 30 000 years ago, or a Neanderthal with CT, or in Eurasia 60 000 years ago. Megalophias (talk) 16:02, 30 April 2020 (UTC)