PROJECT GOALS

The R-M124 haplogroup (see definitions below) is rarely found among the male population of Europe or among the Jewish population. This project aims to identify genealogically relevant DNA markers that are common for both Jewish and non-Jewish members of the project. The project will explore Jewish ancestral origins by collecting and analyzing genetic, geographic, and surname data. See sections below for more discussion of where R-M124 fits in the human phylogenetic tree.

Individuals who belong to the R-M124 haplogroup and who are Jewish or have known Jewish paternal ancestry are highly encouraged to join this project. Although the project focuses on Jewish ancestral origins, non-Jewish R-M124 males with similar Y-DNA markers are also welcome to join the project. Please contact one of the project administrators for more information.

Project members' matching Y-DNA markers will be compared and placed into subgroups, and can be viewed on the "Y-DNA Results" pages of the project. These pages will allow you to see similarities for Short Tandem Repeat (STR) markers, Single Nucleotide Polymorphism (SNP) markers, and the geographic locations of members’ oldest known ancestors.

SOME BASIC DEFINITIONS

The R-M124 mutation represents the defining Y-DNA marker of the R-M124 haplogroup of the human phylogenetic tree. It is now often referred to as the R2a haplogroup (see sections below for a discussion of current R2a Y-DNA phylogenetic trees).

A haplogroup is a major branch on the human family’s phylogenetic tree. The Y-DNA paternal tree traces male lineages, from father-to-son, from ancient times up to the present. When a major genetic mutation, called a single nucleotide polymorphism or SNP (pronounced “snip”) occurs in a male, that person's male descendants will all inherit the new mutation, forming a new haplogroup. Subsequent new SNP mutations may also occur in some of those descendants, thus forming even more branches and haplogroups (these subsequent branches are called "subclades" of the higher-level haplogroup).

R-M124 is one such SNP, the founding father of which is the ancestor of all known R-M124 males living today, most of them carrying additional (i.e., chronologically newer) subclade SNPs. See sections below for more discussion of SNPs.

Closely-related men within the same haplogroup will usually have identical or similar haplotypes. A haplotype is a set of values for a set of DNA markers called Short Tandem Repeats (or STRs). These are different kinds of markers than SNPs. Haplogroups are always defined by SNPs. Haplotypes, on the other hand, are defined by STRs.

For example, the results of a Family Tree DNA (FTDNA) Y-DNA12 test for a person yields their 12-marker haplotype. Two individuals that match exactly on all markers have the same haplotype (see sections below for more discussion of STRs and how to use them). FTDNA states in their DNA FAQ that STR tests are best for recent ancestry (your close relatives) while SNP tests tell about more ancient human ancestry. Click on the DNA FAQ button in the blue bar at the top of the page to access FTDNA’s DNA FAQ for more information.

Today, as more people take DNA tests, recent mutations are defining new branches and leaves on the genetic tree. As new haplogroups (think of these as the branches) become defined, more knowledge is gained about when and where these haplogroups originated. The more recently a mutation occurred, the more likely it is to be meaningful for your own genetic family tree. Ancient people with the same SNP mutations, and therefore the same haplogroup branch, tended to either live in the same geographic location, or to migrate to a new location together. Over time, individuals on a branch maintained similar haplotypes (think of these as the leaves) and their descendants tend to be closely related in genealogical time.

JEWISH R-M124

Jewish men in haplogroup R-M124 usually (but not always) have an Ashkenazi family history. However, they are genetically very similar to people whose ancestors lived in the ancient Babylonian and Persian empires (known today as Iraq and Iran). Modern Jews from those regions are sometimes called Mizrachi Jews. Before the creation of the state of Israel, Mizrachi Jews usually characterized themselves as Sephardi, because they followed the traditions of Sephardic Judaism (see sections below for more discussion on Ashkenazim, Sephardim, and Mizrachim).

Ashkenazi Jews who test as R-M124 are sometimes surprised by their result because it is rare among Jews (only about 1% of all Jewish men who have their Y-DNA tested belong to R-M124). Many have questions about what their R-M124 result means because the majority of Ashkenazi Jews that take Y-DNA tests belong to other haplogroups, such as J1, J2, E, G, R1a, or R1b.

ORIGINS OF R-M124

According to the Genographic Project[1] conducted by the National Geographic Society, the R-M124 haplogroup arose in Central or South Asia, and made its first entry into the Indian subcontinent 25,000 years ago. Today's members of the R-M124 haplogroup are present in northern India, Pakistan, and southern Central Asia at high frequencies. Some modern Turks and Iranians also belong to this haplogroup. However, R-M124 is almost non-existent in Europe, except among Ashkenazi Jews and a small handful of Sinti Romani people.[2,3]

The R-M124 mutation is an outgrowth of an older mutation named R-M479 (one of the SNPs that defines Haplogroup R2). The R-M479 mutation is about 25,000-30,000 years old, but the age of the R-M124 mutation is not precisely known. It may have occurred many thousands of years after R-M479 and current estimates place it about 16,000 years ago. People with R-M124 can learn about their haplogroup on their Y-DNA Haplotree page, where FTDNA says the following about this haplogroup. “The R-M124 lineage began in South Asia. It and its descendants spread there and west to Central Asia and Southeastern Europe. It is now present in Central Asia, Turkey, Pakistan, and India. [It is] also present in groups like the Romani who are from South Asia.”[4]  See sections below for more discussion of Sinti Romani R-M124.

HOW DID JEWS GET INTO THIS HAPLOGROUP?

Another way to ask the question is “How did this haplogroup get into the Jews?” Bennett Greenspan, President and CEO of FTDNA, said in his talk at the International Association of Jewish Genealogical Societies 2013 conference in Boston: “As romantic as it is to presume that all of our ancestors stood at Mt. Sinai waiting for Moses to reappear, in truth only some of our ancestors were Jews 3200 years ago. Haplogroups can give us instant clues of when and perhaps where our ancestors joined the Jewish people.”[5]

Comprehensive Y-DNA testing is now helping to better define the origins, migration and approximate time when members of this haplogroup became Jewish. Jewish R-M124 men have distinctive DNA markers that set them apart from other Jews and from other members of the R-M124 haplogroup. R-M124 men could have stood at Mt. Sinai as part of our ancient Jewish ancestry, or may have joined the Jewish people at a later time. History may provide some clues.

One story likely involves three major geographies: Western Asia (modern Israel, Jordan, Syria, Iraq, Iran, and Turkey), Central Asia (eastern and southern Ukraine and the Caucasus), and South Asia (Afghanistan, Pakistan, and India). People from these areas traveled widely for commerce and for war. Tales of ancient conquests, the Silk Road and the Spice Route are well known.

As mentioned above, current genetic research suggests R-M124 may have originated somewhere near India, and its descendants made their way into the Indian sub-continent through one or more routes.[3] Other R-M124 men likely migrated west into Persia. In Biblical times, Persian armies, probably including R-M124 men, went even further west under Cyrus the Great and conquered ancient Babylonia, where Persians came in contact with the Jewish Babylonian populace that had been exiled as captives after the destruction of the first Temple in Jerusalem in 586 BCE.[6]

It is possible that some exiled Babylonian Jews traveled east into Persia or that Persian R-M124 males converted to Judaism over the next several hundred years during their interactions with Babylonian Jews. Whether or not it is historically accurate, the story of Queen Esther (Esther 8:17) alludes to Persian conversions to Judaism. If such conversions did happen, some Persian converts could be the founding ancestors of the Jewish R-M124 clusters that have been identified through Y-DNA tests.

Other stories exist of Middle East conversions to Judaism. At the beginning of the Common Era, the ruler of the Parthian client kingdom of Adiabene was Izates bar Monobaz, one of the more famous proselytes to Judaism.[7] His mother, Queen Helena of Adiabene, was also a convert, who built palaces in Jerusalem and was buried there.[8] Izates had twenty-four sons, sent by Queen Helena to Jerusalem to learn Hebrew and the Jewish religion. Early in its history, Adiabene was a vassal state under Persian kings, and it is possible that R-M124 men came to Adiabene. One of them may have been a paternal ancestor of King Monobaz I.

One thousand years later, another story presents additional scenarios. Historical accounts of the Khazarian kingdom suggest that Jews from Babylonia were brought to Khazaria as rabbis and teachers around the 9th century CE, when some segments of the local populations were converting to Judaism.[9] Some may have been R-M124 Jews. If that happened, their R-M124 descendants may have remained in Central Asia. Others may have headed north and west into Eastern Europe.

If Jews arrived in Eastern Europe after the break-up of the Khazar kingdom, they eventually merged with the Ashkenazi communities that were migrating east from Western Europe due to pogroms and expulsions. R-M124 Jews likely assimilated over time, adopting Ashkenazi customs and Yiddish as their language. Their R-M124 male descendants came to identify culturally as Ashkenazim. This resembles explanations suggested for the large percentage of R1a1 found within the Ashkenazi Levite population.[10]

Other hypotheses have been suggested to explain R-M124 Jewish clusters among modern-day Ashkenazi Jews. One possibility is a resettlement of Babylonian Jewish families, some of whose male members might have been R-M124, into southern France. In particular, the community of Narbonne has a long history of Jewish settlement[11] and some may have come from Babylonia. More modern migration scenarios might be Mizrachi Jewish families seeking refuge in foreign lands to escape from persecutions in Islamic occupied Babylonia[12] and the Mongol and Muslim dynasties of Persia.[13]

JEWISH CLUSTERS

There are at least two confirmed Jewish clusters of R-M124 individuals, possibly reflecting ancient Babylonian (Iraqi), Persian (Iranian), or Central Asian origins as described above. However, these two clusters appear to be separated by several thousand years.[14]

The first Jewish cluster, which this project and the more general FTDNA R2 Project call “Jewish Group A”, is was previously identified by five Y-DNA SNP mutations - F1092, F1159, F1758, F2791 and F3604.[15] These five SNPs are part of the F-series of Asian SNPs first researched at Fudan University in Shanghai, China, and four of them (but not F2791) were found in Genographic Project Geno 2.0 tests of Jewish R-M124 individuals. Recent Geno 2.0 results imply that F1758 is downstream from the other four, and is an identifier for Jewish Group A. It should be noted that F1758 has also been found in non-Jewish testers from the Middle East that have similar genetic markers. The most recent Big Y tests have now identified SNP FGC13184 as a better and more recent identifier for this cluster, but this SNP is not yet available for ordering from FTDNA. The second Jewish cluster, which is much smaller than Jewish Group A and called “Jewish Group B”, is likely identified by Y-DNA SNP L288.[15] This mutation was first discovered in an early FTDNA Walk Through the Y (WTY) test of an R-M124 individual.

SNPs identifying the two main Jewish clusters of this project (i.e., F1758 for Jewish Group A, and L288 for Jewish Group B) are available as stand-alone advanced order tests from FTDNA (note that SNPs F1092, F1159 and F3604 were also tested on National Geographic's Geno 2.0 chip, and these three are also available as a stand-alone tests from FTDNA). SNP F2791 was recently found in two Jewish Group A Big Y results and is now known to also be shared by all of Jewish Group A. It is also available as a stand-alone test from FTDNA. This project intends to work with FTDNA to develop a custom SNP pack for about 100 SNPs that are at or below the level of SNP FGC13184 and will announce to members when and if such a custom SNP pack can be made available. This might be a more cost effective way to test for relevant Jewish Group A SNPs than ordering a Big Y test.

If you have been placed in Jewish Group A or in Jewish Group B, you may still want to consider ordering the appropriate SNP test to confirm that you are indeed positive for the predicted SNP. However, based on known test results to date, it's very likely that people predicted to be F1758 or predicted to be L288 will test positive for those SNPs, so these SNP tests are not really necessary. Other options for ordering SNPs are discussed below under SNPs and How to Order Them. FOR THE MOST RECENT INFORMATION about SNPs, please refer to the News and Results section of this project. A new update detailing results of recent Big Y tests will be posted soon.

R-M124 PHYLOGENIES

R-M124 (or R2a) represents the largest sub-branch of the R2 phylogenetic tree. This tree is a branching diagram showing inferred ancestral relationships, and is constantly evolving. But there is generally a lag time between the discovery of new SNPs and their placement on the tree. New SNPs that are thought to be associated with Jewish Group A and Jewish Group B are now on the official tree at the International Society of Genetic Genealogy (ISOGG). The current ISOGG tree for Haplogroup R (including, R1a, R1b, and R2) can be found here:

http://www.isogg.org/tree/ISOGG_HapgrpR.html

As of January 1, 2017 the ISOGG R2a tree was defined to be the following (with FGC13184 and L288 highlighted in yellow). Because of continuing research, the structure of the Y-DNA haplogroup trees change and ISOGG does its best to keep the tree updated with the latest developments in the field. The criteria for a representative SNP printed below in bold for a subclade is: traditional usage, testing in multiple labs, and/or being found in the area of the chromosome used in recent research studies. SNPs listed below in italics (colored black or red) are quality variants from next-generation sequencing reports consistently showing as representing that subgroup.

• R2   M479/PF6107, L266/PF6108, L722, L726
• • R2a   M124, F820/Page4, L381, P249
• • • R2a1   L263
• • • R2a2   P267/PF6109
• • • • R2a2a   FGC13188, FGC13192, FGC13203, FGC13212,FGC13217, FGC13220
• • • • • R2a2a1   F1092
• • • • • • R2a2a1a   F1758
• • • • • • • R2a2a1a1   FGC13184
• • • • R2a2b   Y12100/FGC12586
• • • • • R2a2b1   Y8763/FGC12615, PF7499/V2738, FGC12630/V1180,FGC12582/Y8764, M9710, FGC12643/V1946/SK2140
• • • • • • R2a2b1a   L1069
• • • • • • R2a2b1b   FGC17608/Y8766
• • • • • • • R2a2b1b1   FGC17611/Y5080
• • • • • • • • R2a2b1b1a   M2091
• • • • • • • • • R2a2b1b1a1   FGC17661/Y13546
• • • • • • • R2a2b1b2   FGC18148/V3714
• • • • • • • • R2a2b1b2a   SK2142, Z29275, Z29280, Z29276, Z29278, Z29269
• • • • • • • • • R2a2b1b2a1   Y1379, Y1376
• • • • • • • • • • R2a2b1b2a1a   Y1383
• • • • • • • • R2a2b1b2b   L295, FGC18147/Y11798, FGC18149/Y11803,SK2153/FGC18146/V2419, Y12093/Z29160, Y1372, Y17451, Z29158, Y11799,Z29159/Y11801 
• • • • • • • • • R2a2b1b2b1   L723
• • • • • • • • • • R2a2b1b2b1a   L725
• • • • • • • • • • • R2a2b1b2b1a1   L724
• • • • • • • • • R2a2b1b2b2   Y1283, Y1281, Y1282, Y1284, Y1285
• • • • • • • • • • R2a2b1b2b2a   SK2155 
• • • • • • • • • • • R2a2b1b2b2a1   Y1331 
• • • • • • • • • • • • R2a2b1b2b2a1a   Y20020 
• • • • • • • • • • R2a2b1b2b2b   Z29162
• • • • • • • • • • • R2a2b1b2b2b1   V4082, M3349.2/S19922.2
• • • • • • • • • • • • R2a2b1b2b2b1a   YP5340, YP5341, YP5349
• • • • • • • • • • • R2a2b1b2b2b2   Y1292, Y1291, Y1293, Y1294, Y1295 
• • • • • • • • • • • • R2a2b1b2b2b2a   Y1296
• • • • • • • • • • • • • R2a2b1b2b2b2a1   Y1303, Y1299, Y1305, Y1306, Y1308, Y1310,Y1311, Y1312, Y1313, Y1314, Y1315, Y1316, Y1319, Y1321, Y1322, Y1323
• • • • • • • • • • • • • • R2a2b1b2b2b2a1a   Y1325, Y1326, Y1329, Y1330, Y2173
• • • • • • • • • • • • • • • R2a2b1b2b2b2a1a1   Y2174
• • • • • • • • • R2a2b1b2b3   V3467/Y1334
• • • • • • • • • • R2a2b1b2b3a   Y1357
• • • • • • • • • • R2a2b1b2b3b   V2434/Y1340
• • • • • • • • • • • R2a2b1b2b3b1   Y1371
• • • • • • • • • • • R2a2b1b2b3b2   L294.1/L362.1/S312.1
• • • • • • • • • • • • R2a2b1b2b3b2a   V1024/Y1351, Y1352, Y1353, Y1354, Y1347
• • • • • • • • • • • • • R2a2b1b2b3b2a1   FGC18152/V2947
• • • • • • • • • • • • • • R2a2b1b2b3b2a1a   Y17474, Y17475, Y17476, Y17477, Y17478,Y17752, Y17753, Y17754, Y17755, Y17756, Y17757, Y17991, Y17992, Y18120, Y18121,Y18122, Y18123, Y18124, Y18125, Y18126 
• • • • • • • • • • • • • • R2a2b1b2b3b2a1b   FGC7156/Y4665
• • • • • R2a2b2   FGC46676, Y23213. Y23623
• • • • • R2a2b2~L288.1
• • R2b   FGC21706, FGC50198, FGC50325, FGC50333, SK2163,SK2164, SK2165, SK2166
• • • R2b1   FGC50339
• • • • R2b1a   FGC50273

Another experimental R2 phylogenetic tree is maintained at: http://www.yfull.com/tree/R2/. This tree is based on data gathered and analyzed primarily from participants in the 1000 Genomes Project and from people who have submitted their raw data from next-generation sequencing. Information about the 1000 Genomes Project can be found at: http://www.1000genomes.org/

FTDNA also maintains its own version of the phylogenetic tree, different than ISOGG's, based primarily on National Geographic Geno 2.0 and Big Y results. This project is currently analyzing results from recent Big Y tests to explore a hierarchy of SNPs that appear to be below FGC13184, encompassing known Mizrachi and Ashkenazi Jews in the project. As mentioned above, we will attempt to work with FTDNA to see if a customized SNP pack for SNPs known to be at or below FGC13184 can be developed at reasonable cost.

SNPs AND HOW TO ORDER THEM

SNPs are the identifying Y-DNA markers for haplogroups. Jewish Group A is currently identified by SNP F1758. Jewish Group B is currently identified by SNP L288. Both of these SNPs can be ordered as a relatively inexpensive custom test from FTDNA. Please note that there is now a SNP named FGC13184 below F1758 that better delineates Jewish Group A. The project will ask FTDNA to make SNP FGC13184 available for order and to update their haplotree to include this SNP under F1758 as shown above in the ISOGG tree.

There are other ways to determine if you carry these SNP mutations, but they are more expensive. For example, the National Geographic Project’s Geno 2.0 will test your DNA for about 12,000 known SNPS.

FTDNA's BIG Y will test your DNA for 25,000 known SNPs and also explore a significant portion of the entire Y-chromosome as a way to discover new SNPs that may be completely unique to you.

If you are in Jewish Group A, you are probably positive for SNP F1758 (as well as FGC13184). If you are in Jewish Group B, you are probably positive for SNP L288. FOR THE MOST RECENT INFORMATION about SNPs (including information about recent BIG Y tests), please refer to the News and Results section of this project. However, if you would still like to order F1758 or L288, here is how to properly order an SNP through the FTDNA Haplotree & SNPs order feature:

1. Login to your myFTDNA web pages.
 

2. Click on "Y-DNA" in the blue banner.
 

3. Click on "Haplotree & SNPs" in the drop-down menu.
 

4. Find F1758 or L288 in your tree and click on the blue "Add" button on the right.
 

5. Click on the "Order Selected SNPs" blue button at the bottom.
 

STRs AND HOW TO USE THEM

Short Tandem Repeats (STRs) are the identifying Y-DNA markers for haplotypes. While 12 marker haplotypes are useful and can probably be used to identify someone in Jewish Group A or in Jewish Group B, they are of limited use in determining whom you might be closely related to. Testing for more STRs is the best way to find out if you and someone else share a recent common ancestor in genealogical time.

Most FTDNA projects recommend that people upgrade to 67 markers as a practical way to use STR markers. By upgrading to 67 or 111 markers, the project will be better able to define your closest probable relatives within Jewish Cluster A or Jewish Cluster B, and perhaps even able to associate you with a known Jewish rabbinical lineage. Within both of these clusters, there are likely to be several uniquely identifiable paternal lineages. The more STR markers you have, the better you will be able to see who matches you and how far apart you are from others in your cluster.

ASHKENAZIM, SEPHARDIM, MIZRACHIM
 
These groups are ethnic and cultural divisions within the Jewish world. The divisions between all these groups are approximate and their boundaries are not always clear.[16]

Sometimes Ashkenazim and Sephardim mixed together in the Diaspora. When this happened, the smaller group generally assimilated into the dominant group. For instance, as Spanish Jews fled the Inquisition, if they became the dominant group where they settled, they continued to identify as Sephardim. If, however, the local Jews were the dominant group where they settled, the incoming Sephardim usually assimilated. Some North African Jews will identify as Sephardim and some will identify as Mizrachim.

In the United States, many Sephardim assimilated into Ashkenazi communities and the Mizrachi ethnic description is rarely used or correctly understood. In Israel, the Jews of North Africa are sometimes described as Mizrachi, even if they were from Spain at one time.

This project uses the term Mizrachi to denote Jews from the Middle East and ancient areas of Babylonia and Persia (modern day Iraq and Iran) because there is a good chance that those are the areas where Jewish R-M124 originated.

SINTI AND ROMANI R-M124

Beyond Ashkenazi Jews, the R-M124 haplogroup is almost completely non-existent in Europe. The Sinti, a Romani people who came to central Europe during the Middle Ages, are one of the few European populations where R-M124 has actually been found. In a small population of Sinti individuals from Germany who were resettled to Central Asia in the 1940s, R-M124 was found at a surprisingly high frequency of 53%. However, it is difficult to draw meaningful conclusions from this result, since the study is old and only 15 individuals were tested.[17] Newer studies suggest that a more precise ancestral source of European Romani populations is found in Haplogroup H-M82.[18]

In a new paper, a small number of R-M124 men were found in a sampling of 1,200 Sardinians.[19] However, the Sardinian samples are R2a1 (L295+), which is the most common type found in India. Jewish R-M124 is known to be R2a (L295-). More testing and discoveries of SNPs below R-M124 would be required to determine if there are genetic links between the Sinti and Indian, Sardinian, or Jewish R-M124 populations. It is not known whether the Sinti R-M124 samples are L295+ or L295-, since their tests were not recent.

SUMMARY

Haplogroup R-M124 is rare among Europeans and is also rare among Ashkenazi Jews. Its origin remains unclear and is a major motivation for this project. There are Jewish R-M124 individuals that have no known Eastern European Ashkenazi ancestry, but have a long Mizrachi heritage, with paternal lines dating back several hundred years in the Middle East. The existence of both Mizrachi and Ashkenazi Jews with common genetics and shared markers supports the probable shared origins discussed above, perhaps in ancient Babylonia or Persia. Recent genetic studies have suggested that Middle Eastern Mizrachi populations were formed by Jews in the Babylonian and Persian empires who are thought to have remained geographically continuous in those locales.[20] By investigating the Y-DNA markers of R-M124 Jews (and those with similar markers), this project will attempt to shed light on the ethnic origin and genetic makeup of Jews in the R-M124 haplogroup.

NOTES

1.   https://genographic.nationalgeographic.com/

2.   http://en.wikipedia.org/wiki/Haplogroup_R-M207

3.   http://en.wikipedia.org/wiki/Haplogroup_R-M124

4.   http://www.familytreedna.com/

5.   http://www.iajgs2013.org/program_schedule.cfm

6.   http://www.jewishencyclopedia.com/articles/4828-cyrus

7.   http://www.jewishencyclopedia.com/articles/801-adiabene

8.   http://www.sacred-texts.com/jud/josephus/ant-20.htm

9.   http://www.jewishencyclopedia.com/articles/4279-chazars

10.  http://en.wikipedia.org/wiki/Genetic_studies_on_Jews

11.  http://www.jewishencyclopedia.com/articles/11323-narbonne

12.  http://en.wikipedia.org/wiki/History_of_the_Jews_in_Iraq

13.  http://en.wikipedia.org/wiki/Persian_Jews

14.  http://r2dna.org/index.php?topic=91.0

15.  http://www.familytreedna.com/public/R2-M124-WTY/

16.  http://en.wikipedia.org/wiki/Jewish_ethnic_divisions

17.  R. Spencer Wells, et al. (2001): The Eurasian Heartland: A Continental Perspective on Y-Chromosome Diversity. Proceedings of the National Academy of Sciences, Vol. 98, No. 18. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC56946/

18.  Rai N, Chaubey G, Tamang R, Pathak AK, Singh VK, et al. (2012): The Phylogeography of Y-Chromosome Haplogroup H1a1a-M82 Reveals the Likely Indian Origin of the European Romani Populations, PLoS ONE 7(11). http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0048477

19.  P. Francalacci, et al. (2013): Low-Pass DNA Sequencing of 1200 Sardinians Reconstructs European Y-Chromosome Phylogeny, Science August 2, 2013. Vol. 341 no. 6145 pp. 565-569. http://www.sciencemag.org/content/341/6145/565.abstract

Genealogical DNA Testing FAQs and Blogs

http://www.familytreedna.com/faq/
http://dna-explained.com/
http://www.yourgeneticgenealogist.com/
http://en.wikipedia.org/wiki/Genealogical_DNA_test

Haplogroup R2 Projects

http://www.familytreedna.com/public/R2/
http://www.familytreedna.com/public/R2-M124-WTY/default.aspx

Haplogroup R2 Forums (unfortunately, this forum appears to have gone inactive and is no longer available)

http://www.r2dna.org/

Y-DNA Haplogroup Trees

http://www.isogg.org/tree/index.html
http://ytree.morleydna.com/experimental-phylogeny
http://www.yfull.com/tree/

Research Papers Referencing Haplogroup R2

Sengupta et al. (2006): Polarity and Temporality of High-Resolution Y-Chromosome Distributions in India Identify Both Indigenous and Exogenous Expansions and Reveal Minor Genetic Influence of Central Asian Pastoralists. American Journal of Human Genetics. 78 (2). pp. 202–221.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1380230/

Jean-Grégoire Manoukian: A Synthesis of Haplogroup R2 (2006)

http://tinyurl.com/m89ohx4

Research Papers Referencing Jewish Y-chromosomes

Multiple Origins of Ashkenazi Levites: Y Chromosome Evidence for Both Near Eastern and European Ancestries

Contrasting patterns of Y chromosome variation in Ashkenazi Jewish and host non-Jewish European populations
Jewish and Middle Eastern non-Jewish populations share a common pool of Y-chromosome biallelic haplotypes

Babylonian Jewish History

A History of the Jews in Babylonia. Jacob Neusner. Leiden: Brill, 1965-1970. I-V. Reprinted: Atlanta, 1999: Scholars Press for South Florida Studies in the History of Judaism.