A New Subclade of Y Haplogroup J2b
from case studies is presented that allows the definition of a new subclade of
Y Haplogroup J2b-M102. The defining
binary polymorphism of the new subclade is a deletion event in the Y-
About one-fifth of Ashkenazi Jews are members of Y-Haplogroup J2 (Behar, 2004). Previous studies of Ashkenazim did not employ sufficient resolution to understand exactly where the Jewish groups were located in the J2 phylogeny, or if there were any subclades of J2 that were almost exclusively Jewish. The present study focuses on one small part of Haplogroup J2 and demonstrates that a new subclade of Haplogroup J2b-M12 may be defined. All members of the subclade who have been identified so far are Ashkenazi and Cohanim, though the sample is small.
Figure 1 provides a simplified overview of Haplogroup J2 (ISOGG, 2007) and shows the location and phylogenetic structure of Haplogroup J2b.
Figure 1. Simplified phylogenetic chart for Haplogroup J2 according to ISOGG (2007). Text in red font indicates defining binary polymorphisms.
It is probable that the binary polymorphism (BP) M102 may be redundant with M12, but previous publications of Haplogroup J phylogenetic trees, including that of ISOGG (2007), still show these BPs as reflected in Figure 1. It is likely that there will be other changes to the 2008 version of the ISOGG tree, necessitated by the publication of new results during the past year.
Haplogroup J2b1-M102, there are presently two subclades, J2b1a defined by M241
and J2b1b defined by M205 (ISOGG, 2007).
Note that some phylogenetic trees have the position of M241 and M205
interchanged, so in this article, the defining BP will be used to make it clear
which subgroup is intended. On the basis
of limited data, J2b1a-M241 appears to be the larger of the two subgroups
(Sengupta 2006). Several customers of
subjects were recruited who had previously been tested and found to be M205+,
along with four subjects who had previously been tested as M241+. Two of these eight subjects had been tested
on both M241 and M205. Four subjects who
were M102+ and who had
public databases of the Sorenson Molecular Genealogy Foundation (SMGF),
Y-Search, and Y-Base were searched for occurrences of
present study, testing of M241 was carried out on selected subjects by
results for each subject on several BPs are shown in Table 1. These results can be used to locate the
following discussion and in Table 1, the BP representing the deletion
Placement of the New Subclade Within J2b1
the subjects in the present study who have
Therefore, we now develop a logic model for placing a new subclade within this or a similar structure. The approach is to lay out all of the possible placements for the BP 455del. In most cases, only a single counter example is necessary to disprove a potential placement, though a second confirming case is helpful in ruling out lab errors. If all possible placements except for one can be disproved, then the remaining one is the correct one. Looking only for positive evidence for the most likely placement would require a large number of subjects to provide reasonable assurance of the placement being correct. The present approach is efficient in that only a small number of well-chosen subjects will suffice to place the new subclade.
a. In the following discussion, Figure 2 outlines all of the possible placements of the new subclade of J2b1 defined by 455del. We will consider each possibility in turn, and show what would be necessary to negate or disprove each possibility. The possibility remaining after this process of elimination, the one that cannot be rejected, is the correct placement.
Figure 2. The seven
possible phylogenetic locations for the deletion event in
b. The 455del is upstream from both M241 and M205 as shown in Figure 2b.
In this case, all M241+ and M205+ subjects will also have 455del. However, if any one M241+ or M205+ subject does not have the 455del, then this possibility is rejected. In this study subjects 101-104 are M241+ and 105-108 are M205+ and all have 455del- (e.g., they do not have the deletion). Therefore, this possibility is rejected.
c. 455del is redundant with M241 as shown in Figure 2c.
To disprove this possibility, we need only to find at least one 455del+ subject who has M241-, or at least one M241+ who has 455del-. In the present study, subjects 101-104 are all M241+, but none has the deletion. Therefore, this possibility is rejected.
d. 455del is redundant with M205 as shown in Figure 2d.
To disprove this possibility, we need only to find at least one 455del+ subject who has M205-, or at least one M205+ subject who has 455del-. In the present study, subjects 105-108 are all M205+, but none has the deletion. Therefore, this possibility is rejected.
e. 455del is upstream on the branch leading to M241 as shown in Figure 2e.
To disprove this possibility, we need only find at least one M241+ subject who is negative for 455del. This disproof is provided by subjects 101-104, all of whom are M241+ and 455del-.
f. 455del is upstream on the branch leading to M205 as shown in Figure 2f.
To disprove this possibility, we need only show that there exists at least one M205+ subject who is negative for 455del. This disproof is provided by subjects 105-108, all of whom are M205+ and 455del-.
g. 455del is downstream from M241 as shown in Figure 2g.
disprove this possibility, we would need to find a subject who exhibits the
h. 455del is downstream from M205 as shown in Figure 2h.
disprove this possibility, we would need to find a subject who exhibits the
Summarizing, we have shown that every possibility except for (g) has been disproved. Since one possibility must be true, it must be (g). Indeed, subjects 109 and 112 have results that are consistent with 455del being downstream from M241.
Placement of the New Subclade Within J2b1a-M241
Haplogroup J2b1a-M241, there are already three previously known subgroups
(ISOGG 2007), so the subclade defined by 455del could be (1) a fourth subgroup
in parallel to the existing three subgroups, (2) downstream from one of the
three, (3) upstream from one or more of the three, or (4) redundant with one of
the three. In principle, we could use
the same kind of logic model and apply it to the placement of 455del within
J2b1a-M241. However, at the present
time, only two BPs, M99 and M280, out of the three defining these three
subgroups of J2b1a-M241, have commercially available tests, so the exact
placement of the new subclade cannot be completely resolved at this time. Subjects 109 and 112, who have
Figure 3 Haplogroup J2b1 with the new subclade shown (simplified for clarity).
appropriate for use for phylogenetic purposes, the Y-
Criterion 1. The marker should be quite stable at its new value, with essentially no chance of reverting to its previous value of 11.
Criterion 2. Further mutations in the marker should not produce an allele frequency distribution that overlaps the former distribution.
Criterion 3. The deletion event should be “almost unique,” perhaps occurring no more than a few other times in human history. There are several BPs on the Y phylogenetic tree that have occurred two or more times in different parts of the tree. Where BPs are not unique, they must be easily interpretable within the context of the phylogeny. Absolute uniqueness has never been required of a marker on the Y tree.
characteristic should be mentioned, though it applies to other types of markers
as well—the marker should be useful for phylogenetic purposes. For example, there is no reason to use the
with the last criterion, the value
of 168 haplotypes that had been tested and found positive for one of the
defining BPs for Haplogroup I1a (usually M253) was extracted from public
surname project web pages at the FTDNA web site. Duplicates from the same surname cluster were
not included. 166 of the haplotypes had
a value of 8 on
J is older than I1a, so we would expect to see a broader distribution of repeat
a small number of members of Haplogroup J2b-
all three criteria are satisfied and the deletion event in
be noted that this is not the first use of a Y-
Origins of the Subclade
currently 10 people in the database of FTDNA who have
those members of J2b-
also possible that non-Jewish members of the new subclade may eventually be
identified. Additionally, with a larger
sample size, we might locate Ashkenazim within the new subclade without a
tradition of being Cohanim. We cannot
rule out these possibilities because of the small number of members of the
subclade identified so far, and the possibility of selection bias. In future studies of Ashkenazi Jews, of
Cohanim, or of Haplogroup J2b, it would be very helpful if
2 shows the Y-
None of the Subjects 109-112 knows of a genealogical connection to any of the others, and all four have different surnames. Using Subject 112 as a point of comparison, the time-to-the-most-recent-common-ancestor (TMRCA) calculator used by FTDNA, called “FTDNATiP,” on the other two subjects who have 37 markers reported (Subjects 109 and 110) results in a 50% probability of a TMRCA at 3 and 6 generations, respectively. Using only the 25 markers in common to Subjects 112 and 111, the calculator provides a corresponding 50% TMRCA at 12 generations. Clearly, this is an inadequate sample for precise determination of when the most recent common ancestor lived, but it is also clear that it is very likely that this ancestor lived in the last millennium.
The present study has identified a new subclade of Haplogroup J2b and the subclade has been shown further to be a subgroup of Haplogroup J2b1a-M241. Precise placement of the new subclade with respect to the previously known subgroups of J2b1a-M241 must await the development of tests for their defining BPs and the identification of subjects who are positive for each of them.
about a dozen members of the new subclade have been identified so far, and only
about half of these have responded to inquiries, but all who responded have
indicated Ashkenazi and Cohanim backgrounds for their paternal lines. The geographic origin of the paternal lines,
where known, was most often indicated as
information is accumulated, the new subclade may be found to include non-Jewish
members. However, with the apparently
young age of the subclade—only several hundred years—it is also possible that
the deletion event in
Semino (2004) found that 1.2% of his Ashkenazi subjects were M102+, which represents about 5% of Ashkenazi J2’s. The new subclade is too small to include all of these J2b’s. An interesting question for future studies is, where are the other J2b Ashkenazim in the J2b phylogeny? Some are probably in J2b-M241*, but we do not know at present if there are significant numbers in J2b-M205.
http://www.ysearch.org genetic genealogy database
http://www.ybase.org genetic genealogy database
http://www.smgf.org genetic genealogy database
http://home.comcast.net/~hapest5/index.html haplogroup predictor
Behar DM, Thomas MG, Skorecki K, Hammer MF, Bulygina E, Rosengarten D, Jones AL, Held K, Moses V, Goldstein D, Bradman N, Weale ME (2003) Multiple origins of Ashkenazi Levites: Y chromosome evidence for both Near Eastern and European ancestries. Am J Hum Genet 73:768–779.
Di Giacomo F, Luca F, Popa LO, Akar N, Anagnou N, Banyko J, Brdicka R, Barbujani G, Papola F, Ciavarella G, Cucci F, Di Stasi L, Gavrila L, Kerimova MG, Kovatchev D, Kozlov AI, Loutradis A, Mandarino V, C. Mammi C, Michalodimitrakis EN, Paoli G, Pappa KI, Pedicini G, Terrenato I, Tofanelli S, Malaspina P, Novelletto A (2004) Y chromosomal haplogroup J as a signature of the post-Neolithic colonization of Europe. Hum Genet 115:357-71.
ISOGG--International Society of Genetic Genealogy (2007) Y Haplogroup Tree. Web Site URL:
King RJ, Ozcan SS, Carter T, Kalfoğlu E, Atasoy S, Triantaphyllidis C, Kouvatsi A, Lin AA, Chow CE, Zhivotovsky LA, Michalodimitrakis M, Underhill PA (2008) Differential Y-chromosome Anatolian influences on the Greek and Cretan Neolithic. Ann Hum Genet. 72:205-214
Rootsi S, Magri C, Kivisild T, Benuzzi G, Help H, Bermisheva M, Kutuev I, Barac L, Pericic M, Balanovsky O, Pshenichnov A, Dion D, Grobei M, Zhivotovsky LA, Battaglia V, Achilli A, Al-Zahery N, Parik J, King R, Cinnioglu C, Khusnutdinova E, Rudan P, Balanovska E, Scheffrahn W, Simonescu M, Brehm A, Goncalves R, Rosa A, Moisan JP, Chaventre A, Ferak V, Furedi S, Oefner PJ, Shen P, Beckman L, Mikerezi I, Terzic R, Primorac D, Cambon-Thomsen A, Krumina A, Torroni A, Underhill PA, Santachiara-Benerecetti AS, Villems R, Semino O (2004) Phylogeography of Y-chromosome haplogroup I reveals distinct domains of prehistoric gene flow in Europe. Am J Hum Genet 75:128-137.
Semino O, Magri C, Benuzzi G, Lin A, Al-Zahery N, Battaglia V, Maccioni L, Triantaphyllidis C, Shen P, Oefner PJ, Zhivotovsky LA, King R, Torroni A, Cavalli-Sforza LL, Underhill PA, A Santachiara-Benerecetti S (2004) Origin, diffusion, and differentiation of Y-Chromosome haplogroups E and J: Inferences on the neolithization of Europe and later migratory events in the Mediterranean area. Am J Hum Genet 74:1023-1034.
Sengupta S, Zhivotovsky LA, King R, Mehdi SQ, Edmonds CA, Chow CT, Lin AA, Mitra M, Sil SK, Ramesh A, Rani MVU, Thakur CM, Cavalli-Sforza LL, Majumder PP, Underhill PA (2006) Polarity and temporality of high resolution Y-chromosome distribution in India identify both indigenous and exogenous expansions and reveal minor genetic influence of central Asian pastoralists. Am J Hum Genet , 78:202-221.