Talk:Haplogroup J (Y-DNA)

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[edit] E3b1 a "loyal fellow traveller?"

What is the origin of the statement, "....Indian J2 is not accompanied by its "loyal fellow-traveller" E3b1 that penetrated to the Near East from North Africa after the end of the Ice Age and is tightly bound with the spread of both J-subbranches since the neolithic era."?

It's true E3b can sometimes be found in the same region as J2. But that hardly warrants calling them "fellow travelers". Furthermore, recent studies by Cruciani suggest the largest European concentration of E3b1 (v13) (the so called alpha cluster)- which incidentally is virtually absent from areas outside of southeastern Europe - may be much older than previously believed. It could have as easily been around the Balkans before the neolithic. Most certainly it got there before the end of the LGM when that part of Europe was a refuge. It got to the near east a lot earlier than that.

So please provide a source for the interesting and misleading statement quoted above.

75.54.183.225 22:59, 16 December 2006 (UTC)grandcross

The presence of J2 in India (and mainly in Pakistan) can be explained as a result of the Neolithic expansion from the Near East to Baluchistan ca. 7000 BC. The same is valid for G. These Y-haplogroups may have spread agriculture to the Proto-Dravidians in Baluchistan and subsequently got with (Proto)Dravidians to India in the 4th millenium BC. The presence of G, J2 and E3b1a in the Balkans still wasn't fully explained; it is possible - as recently Dienekes Pontikos suggested - that J2, G and R1b1 (the Anatolian haplotype) were present both in the Asia Minor and in Greece before the Neolithic expansion. The distribution of E3b1a indicates that it got to the Balkans by sea rather than through the Asia Minor - or at least, it didn't leave any significant traces in the Asia Minor. And as Cruciani recently suggested, E3b1a may, in fact, be a result of a demographic expansion during the Bronze Age ca. 2000-2700 BC, together with J2b. However, its diversity indicates an origin in Western Asia ca. 9500 BC. This is in accordance with the presence of E3b1 in the Near East during the Neolithic, and thus the expansion of J2 and G to India very probably occured before E3b1 aarived from Africa to the Levant. Still, since the connection between E3b1a and the Neolithic expansion from the Asia Minor is now doubtful, I will change the sentence. 82.100.61.114 13:57, 23 June 2007 (UTC)

[edit] "The Cohen Modal Haplotype falls in haplogroup J1, with respect to Cohens" ?

I've put a source-request tag on this, because although it does seem to be the folk-assumption, I can't seem to find reference on the net to any primary source or primary data that establishes it.

  • Behar (2003) [1] (page 772) found 86% of Ashkenazi Cohens and 76% of Sephardi Cohens belonging to Haplogroup J as a whole but (rather strangely?) seems not to have tested with M172 to distinguish J1 and J2, and does not report the proportion of those in Haplogroup J with the Cohen Modal Haplotype (CMH).
  • Levy-Coffman (2005) [2] (page 4) says 48% of Ashkenazi Cohenim and 58% of Sephardi Cohenim belong to Hg J1 with the CMH, citing Skorecki et al (1997). But that's surely not the right reference, because that paper [3] only tested one STR locus and only one SNP -- namely YAP, which is indicatative of the Haplogroup DE branch.
— The Y-STR percentages are from Thomas et al (1998). But that paper only narrowed the Haplogroup to YxDE,PR. Jheald 19:05, 27 February 2007 (UTC)
  • On the other hand Dienekes' blog in a 2005 commentary [4] cites Malaspina et al (2001) [5] as having typed a number of Italian Cohanim, and found them to belong to the J2 haplogroup. (But I don't have access to the paper, so can't check he's translated their naming conventions correctly).

Can anyone supply a definitive reference, estimating the actual proportion of Cohanim in J1 with the CMH (presumably high), and the proportion in J2 with the CMH (presumably low) ? Jheald 18:52, 27 January 2007 (UTC)

I have since found there was quite a long discussion on this very point on the Genealogy-DNA-L list in March 2006. [6]. It seems that researchers must have this (comparatively simple) information, but for reasons unclear it has never been made public.
The discussion cast doubt on putting too much weight on the Malaspina reference - on closer reading it seems he may only have Y-STR typed the Italian Cohanim, and never actually SNP tested them.
The view of those closest to some of the studies on Jewish surnames seems to be that the Cohens are definitely connected to J1 rather than J2. Also, apparently, FTDNA (who probably have the best data on this) now only mention the possibility of Cohanim descendency on their J and J1 results pages, not J2. But as far as I can understand, there seem as yet only to be these rather informal straws in the wind, nothing more definite. Jheald 00:47, 28 January 2007 (UTC).
More detailed information since added to the Cohen modal haplotype page. For reasons presented at more length in the talk page there, I'm now happy with this article's current statement "Jewish Kohanim with the CMH appear to be definitively associated with haplogroup J1 rather than J2". Jheald 09:49, 19 May 2007 (UTC)

[edit] J1 + CMH "considered the Jewish Priestly Signature"

According to the current version of the article,

"Although you can have the CMH in either J1 or J2, it is the genetic signature in J1 that is considered the Jewish priestly signature".

This phrasing seems dangerously close to inviting readers to fall into the Conditional probability fallacy (also called the Prosecutor's fallacy), namely the mistaken assumption that because the probability of a genetic marker given a particular state, P(marker|state), is very high, that this necessarily implies that the probability of the state given the marker, P(state|marker) is similarly high.

But this is not the case. Across the whole population of Haplogroup J1, the total number of people who fall into the 1 to 4% that match the CMH purely by chance will actually be much larger than the comparatively small number with actual Cohen descent.

As for example genetic surname projects have found, only if much more specific genetic tests are used, testing a much larger number of marker locations, can high kinship probabilities be established with any certainty. Jheald 10:22, 28 January 2007 (UTC)

Article now deals with this more carefully, I think. Jheald 09:49, 19 May 2007 (UTC)

[edit] 22 subhaplogroups of J2?

About this statement: "However, J2 has been found to encompass several subhaplogroups (22 subhaplogroups, including 12 that have high frequencies) that originated or expanded in different regions. . ."

1) Why are we using the term "subhaplogroups," when the term "subclades" is much more frequently used, and not as unwieldy?

2) "12 that have high frequencies"!? Which 12 would those be? I would like to see the list of which 12 J2 subclades the author of this statement believes to be of high frequencies. The number is far fewer than that, from all the data I have seen. I'll try to come back with a more accurate figure soon.

Iris-J2 05:21, 19 May 2007 (UTC) Bonnie

You're right, this does look questionable.
The apparently cited source for the statement is Semino et al (2004), who use the term "subhaplogroup". Figure 2 of that paper shows Haplogroup J dividing into 21 branches - which would give 22 subgroups, if one included J* as well. 12 of the branches are connected with solid lines rather than dotted, indicating that they were observed in the study.
But these are subgroups of Hg J, rather than J2. And of the subgroups in J2 they did observe, Semino et al wrote that: "four [occurred] at informative frequencies". These were J-M172* (J2a1* and J2a1k), J-M102 (J2b1), J-M67 (J2a1b) and J-M92 (J2a1b1). These are the subgroups Semino et al have enough data to identify distinctive geographical patterns for.
Of course, since that time new SNPs have been identified (and will continue to be identified). So giving a total count of subhaplogroups is probably not a good idea, particularly as the article now quotes the whole ISOGG whole tree in full. Maybe best to rewrite it as something like "J2 has been found to include several subhaplogroups (most prominently J-M172* (J2a1* and J2a1k), J-M102 (J2b1), J-M67 (J2a1b) and J-M92 (J2a1b1)), that originated or expanded in different regions"; and add notes to the ISOGG tree extract about their main geographical centres, as has been done in some other haplogroup articles.
Jheald 09:49, 19 May 2007 (UTC)

I am getting rid of Kurdistan as a list of countries that the halogroup are in and saying the province of Kurdiatan in Turkey and N. Iraq. —Preceding unsigned comment added by Atilla1234 (talk • contribs) 06:13, 9 February 2008 (UTC)

[edit] It is most closely related to Haplogroup I, as both Haplogroup I and Haplogroup J are descendants of Haplogroup IJ (S2, S22).

This statment above is backwords. IJ is theoretical. It has never been found but it's existance in infered by the simlarities between I and J. The article essentially states the opposite. Claiming that I and J are closely related because they come from IJ. Actually they are said to come from IJ becuase they were aleady recognized as closely relatedHeathcliff (talk) 14:33, 12 February 2008 (UTC)

[edit] Proposal to create a new WikiProject: Genetic History

I have put up a suggestion at Wikipedia:WikiProject Council/Proposals to create a new WikiProject, WikiProject: Genetic History.

To quote from what I've written there:

Description
A wikiproject for articles on DNA research into genetic genealogy and genealogical DNA tests; the history and spread of human populations as revealed by eg human Y-chromosome and mitochondrial DNA haplogroups; and similar. Many such articles can be found in Category:Genetic genealogy and its subcategories, notably the subcategories on human haplogroups.
Rationale
  • My direct motivation for seeking this Wikiproject was a recent run-in at Y-chromosomal Aaron, where I desperately missed the lack of a relevant WikiProject talk page to go to, to attract the input, advice and views of knowledgeable editors in this area.
There's a lot of general public interest in the proposed subject area -- eg the Y-chromosomal Aaron page is apparently getting well over 100 hits a day, and over the last 18 months or so there's been a lot of material added, by a fair number of different editors, mostly editing different pages which are particularly relevant to them. IMO, a central wikiproject would be useful, and also a good place to be able to bring WP:OR, WP:V, and WP:general cluelessness issues for wider informed input.
Wikipedia:WikiProject Molecular and Cellular Biology and Wikipedia:WikiProject Evolutionary biology do already exist, but their focus is much much broader. With regard to those project's charters, I believe the subject would be seen as a rather specialist niche topic area, rather out of the mainstream of those project's normal focus. On the other hand, I believe that there are a number of wikipedia editors (and readers) who are specifically interested in the subject, who would find advantage if there were a specific wikiproject for it. Jheald (talk) 12:56, 22 February 2008 (UTC)

If people think this would be a good idea, it's a target for WikiProjects to have at least five "interested" signatures to show there's some support, before they get going.

Alternatively, if people think it would be a bad idea, please leave a comment in the comments section.

Either way, please show what you think, at Wikipedia:WikiProject_Council/Proposals#Genetic_History

Thanks, Jheald (talk) 13:45, 22 February 2008 (UTC)


HAPLOGROUP J ORIGINATED IN IRAN. IT SHOWS HIGHEST DIVERSITY THERE, AND SHOWS A PEAK IN SOUTHWEST IRAN WHERE SOME OF THE OLDEST EVIDENCE FOR FARMING IS FOUND. —Preceding unsigned comment added by 76.224.35.1 (talk) 17:23, 12 April 2008 (UTC)