Observations re 561-Marker STR Results for Big Y-Tested R1a-Y2619 Ashkenazi Levites

[This page was written in 2018. Its observations remain generally valid; statements made with regard to the R1a-BY29826 cluster as characterized by DYS537=12 and DYS650=12 apply equally to the more recently identified R1a-BY73299 cluster. (This page does not analyze the 838-marker results that FTDNA subsequently started to report as part of the Big Y-700 test.)]

In April 2018, FTDNA started to report 561-marker STR results based upon Big Y results for men who have done Big Y testing. (Upon replacing the Big Y-500 test with the Big Y-700 test, FTDNA started to report 838-marker results.)

The R1a-Y2619 Ashkenazi Levite sortable spreadsheet posted at the bottom of this website’s Y-DNA Analysis page now includes a page with 561-marker and 838-marker results.

Information concerning the STR deviation frequencies on markers 112 through 838 has been added to this website’s page on STR Mutation Frequencies Generally and STR Deviation Frequencies Among R1a-Y2619 Ashkenazi Levites.

General Observations

The marker values on markers 1 through 111 are reported by FTDNA based upon STR testing, while the marker values on markers 112 through 561 have been pulled from data compiled through Big Y next generation sequencing. (Accordingly, men who did Big Y testing after having tested only to, e.g., 37 markers or 67 markers are typically not reported as having results on markers 38 through 111 or markers 68 through 111, respectively.)

This page provides initial observations based upon analysis of 561-marker results for 81 of the 124 R1a-Y2619 Ashkenazi Levites who had received Big Y results as of May 12, 2018. The spreadsheet posted at the bottom of this page provides 561-marker results for those men, sorted by cluster and then by subcluster to facilitate determination as to which STR marker values appear to be characteristic of particular subclusters of R1a-Y2619 Ashkenazi Levites.

The STR marker values (i.e., the number of repeats) for R1a-Y2619 Ashkenazi Levites on markers 112 through 561 range from 4 to 15.

FTDNA’s choice of STRs with relatively few repeats to report as markers 112 through 561 – by contrast, FTDNA reports several STRs with more than 30 repeats on markers 1 through 111 for R1a-Y2619 Ashkenazi Levites – presumably reflects the difficulty in using the Big Y test’s next generation sequencing to determine the number of repeats in STRs with a large number of repeats.

FTDNA is reporting results for a given marker on markers 112 through 561 only if it finds that the data is sufficient to allow the marker value to be reliably reported; markers for which FTDNA cannot confidently provide an STR marker value are identified with a hyphen, rather than a number. (The reason why FTDNA now markets the Big Y test under the name Big Y500 is that it promises to report at least 500 STR marker values for each tested man.)

As of May 12, 2018, this site has compiled 81 sets of 561-marker results for R1a-Y2619 Ashkenazi Levites. Three of those kits report results for all 450 STRs on markers 112 through 561. About 68% of the kits are missing 10 or fewer STRs on markers 112 through 561 (for a reporting rate of 97.8% or greater of the STRs in that range); about 86% of the kits are missing 20 or fewer STRs on those markers (for a reporting rate of 95.6% or greater of the STRs in that range). However, there are three kits that are missing more than 50 STRs on markers 112 through 561 (for a reporting rate in the neighborhood of only 88% of the STRs in that range).

Most of the STRs on markers 112 through 561 have very few reported non-reads. However, there are several markers – FTY73 (marker no. 381), FTY905 (marker no. 481), DYS642 (marker no. 494), FTY1039 (marker no. 511), FTY1053 (marker no. 523), and FTY1006 (marker no 559) – on which non-reads are relatively common, with non-reads ranging from 14.8% to 18.5%. (For current information concerning the STR deviation frequencies on markers 112 through 561, click here or see the third page of the most recent version of the R1a-Y2619 Ashkenazi Levite sortable spreadsheet posted at the bottom of the Y-DNA Analysis page of this website.)

The STR marker values that are reported by FTDNA are highly consistent among all of the tested men, indicating that FTDNA’s reported results on markers 112 through 561 are quite reliable.

Observations Specific to R1a-Y2619 Ashkenazi Levites

There is no variation among the tested R1a-Y2619 Ashkenazi Levites on most of the STRs on markers 112 through 561; on numerous other STRs in that range, there are currently only one or two R1a-Y2619 Ashkenazi Levites with STR marker values that differ from the R1a-Y2619 Ashkenazi Levite modal values. This suggests that the vast majority of STRs on markers 112 through 561 mutate very slowly, making them of more use in defining haplogroups than clusters within a genealogical timeframe.

There are, however, about 27 STRs on markers 112 through 561 where multiple R1a-Y2619 Ashkenazi Levites have marker values that differ from the R1a-Y2619 Ashkenazi Levite modal value for those markers. By considering the STR marker values on markers 112 through 561 in conjunction with information provided by Big Y testing concerning subclustering among R1a-2619 Ashkenazi Levites, it is possible to determine which STR marker values are likely of genealogical significance, and which STRs likely mutate too frequently and independently to be of genealogical use (except in identifying very close matches).

About 18 STRs on markers 112 through 561 have mutated independently in more than one R1a-Y2619 Ashkenazi Levite cluster or subcluster in the 1,743 years since the time of the R1a-Y2619 progenitor. Such independent mutations on an STR suggest that the STR mutates relatively frequently, making it more difficult to identify those STR marker values that are likely characteristic of a particular cluster of R1a-Y2619 Ashkenazi Levites.

The attached version of the 561-marker spreadsheet, sorted by R1a-Y2619 Ashkenazi Levite cluster and subcluster as determined through Big Y testing, provides some insight into which STRs on markers 112 through 561 are of use in placing R1a-Y2619 Ashkenazi Levites into subclusters and which STRs may mutate too frequently to be of genealogical use.

I note the following:

1. Perhaps the most interesting STR for R1a-Y2619 Ashkenazi Levites on markers 112 through 561 is DYS541 (marker no. 321). On that marker, and considering results received through May 12, 2018: (a) all but one of the men who belong to the R1a-Y2630 cluster (i.e., Y2619 => Y2630) have the R1a-Y2619 Ashkenazi Levite modal value of DYS541=13 (this statement is circular; the reason that DYS541=13 is the modal value is that more than half of R1a-Y2619 Ashkenazi Levites belong to the R1a-Y2630 cluster); (b) most members of the R1a-FGC18222 cluster (i.e., Y2619 => FGC18222) have DYS541=14 (members of the R1a-YP4487 subcluster (i.e., FGC18222 => FGC18226 => FGC18215 => YP1385 => YP4487) have DYS541=15, two steps from the modal value); (c) the majority of members of the R1a-BY29826 cluster (i.e., Y2619 => BY29826) have DYS541=14; and (d) almost all of the men who are reported as belonging to the R1a-Y2619* subcluster (i.e., those men who belong to the R1a-Y2619 subcluster but are not reported as Y2630+, FGC18222+, or BY29826+) have DYS541=14.

Some background is necessary to explain the significance of these results. From the early days of 111-marker testing, and as discussed elsewhere on this website, it was apparent based upon review of STR marker values at 111 markers that there were two major clusters of R1a-Y2619 Ashkenazi Levites: (a) a somewhat larger cluster, characterized by the marker values DYS537=12 and DYS650=20; and (b) a somewhat smaller cluster, characterized by the marker values DYS537=11 and DYS650<20. There was also a small group of R1a-Y2619 Ashkenazi Levites with the intermediate pair of marker values DYS537=12 and DYS650=19; based upon their marker values, it appeared that some of those men likely belonged to one of the first two clusters (with an independent mutation on either DYS537 or DYS650), but that there were other men who might belong to a third cluster.

Through SNP testing and analyses like those done presented on this website, by the FTDNA R1a project, and the YFull R1a tree, it was determined that the somewhat larger cluster (with DYS537=12 and DYS650=20) was characterized by the SNP Y2630, while the somewhat smaller cluster (with DYS537=11 and DYS650<20) was characterized by the SNP FGC18222.

It was also determined that many of the men with the intermediate marker values DYS537=12 and DYS650=19 were negative for both Y2630 and FGC18222. Most such men were originally characterized as R1a-Y2619* (the asterisk indicated that such men did not yet have a terminal SNP downstream from the Y2619 level); there were a few men who were negative for both Y2630 and FGC18222 who shared the SNP YP3939, downstream from R1a-Y2619, and those men were designated as R1a-YP3939.

After FTDNA revised its Big Y reporting methodology in late 2017, all but three of the men previously identified as R1a-Y2619* - as well as the R1a-YP3939 men – were reported as positive for BY29826 (a SNP that FTDNA had previously not reported, by name or position, for such men). As discussed below, FTDNA did not report results – positive or negative – for BY29826 for two of these men, and their STR marker values on markers 112 through 561 suggest strongly that those men both belong to the BY29826 cluster.

However, a fourth R1a-Y2619* man (Laudon, kit no. 382222) is reported as negative for BY29826, indicating the existence of an R1a-Y2619* line alongside the R1a-FGC18222, R1a-Y2630, and R1a-BY29826 lines. [Subsequent analyses showed that Laudon belongs to R1a-BY73299, a fourth R1a-Y2619 line. The analysis below with regard to the R1a-BY29826 line is equally applicable to the R1a-BY73299 line as to STRs on markers nos. 1-111; both lines share DYS537=12, DYS650=19, and DYS570=21.]

By definition, the R1a-FGC18222 line, the R1a-Y2630 line, and the R1a-BY29826 line must have each branched off from the R1a-Y2619* line rather than from one of the other lines. (Put otherwise, if, for example, the R1a-BY29826 line had branched off from the R1a-FGC18222 line or the R1a-Y2630 line, the SNP FGC18222 or Y2630 would be found in the R1a-BY29826 cluster; the absence of either SNP in R1a-BY29826 men means that R1a-BY29826 did not branch off from either such line.)

While the possibility of independent mutations on STRs precludes certainty, one may draw an inference that any marker value that is shared by all but one of the R1a-FGC18222, R1a-Y2630, R1a-BY29826, and R1a-Y2619* clusters was likely inherited from the R1a-Y2619 MRCA, the progenitor from which all four clusters are descended. Based upon such inference, the R1a-Y2619 MRCA would have had: (a) DYS537=12 (shared by the R1a-Y2630, R1a-BY29826, and R1a-Y2619* clusters, but not the R1a-FGC18222 cluster); (b) DYS650=19 (shared by the R1a-FGC18222, R1a-BY29826, and R1a-Y2619* clusters, but not the R1a-Y2630 cluster); (c) DYS570=21 (shared by the R1a-FGC18222, R1a-BY29826, and R1a-Y2619* clusters, but not the R1a-Y2630 cluster); and (d) DYS541=14 (shared by the R1a-FGC18222, R1a-BY29826, and R1a-Y2619* clusters, but not the R1a-Y2630 cluster).

2. There are three shared deviations from the R1a-Y2619 Ashkenazi Levite modal value on markers 112 through 561 that are characteristic of subclusters within the R1a-Y2630 cluster.

First, the marker value FTY185=9 (marker no. 26) (the R1a-Y2619 Ashkenazi Levite modal value is FTY185=8) is characteristic of the R1a-YP266 subcluster (i.e., Y2630 => YP266), the largest subcluster within the R1a-Y2630 cluster.

Second, the marker value FTY235=10 (marker no. 425) (the R1a-Y2619 Ashkenazi Levite modal value is FTY235=11) is shared by the three men who belong to the R1a-YP5304 subcluster (i.e., Y2630 => YP266 => YP264 => YP265 => YP268 => YP5303 => YP5304), a subcluster that includes three known direct male descendants of the Horowitz rabbinical family who share a direct male ancestor in the 17th century.

Third, the marker value DYS523=16 or DYS523=17 (marker no. 438) (the R1a-Y2619 Ashkenazi Levite modal value is DYS523=15) is characteristic of the R1a-YP1386 subcluster (i.e., Y2630 => YP1387 => YP1386).

3. There are three shared deviations from the R1a-Y2619 Ashkenazi Levite modal value that are characteristic of the R1a-FGC18222 cluster.

First, the marker value DYS523=16 (marker no. 438) (the R1a-Y2619 Ashkenazi Levite modal value is DYS523=15) is characteristic of the R1a-FGC18222 cluster in its entirety.

Second, the marker value FTY299=11 (marker no. 264) (the R1a-Y2619 Ashkenazi Levite modal value is FTY299=12) is characteristic of the R1a-FGC36607 subcluster (i.e., FGC18222 => YP1074 => FGC36607).

Third, the marker value DYS602=7 (marker no. 502) (a five-step mutation from the R1a-Y2619 Ashkenazi Levite modal value of DYS602=12) is characteristic of the R1a-YP4487 subcluster (i.e., FGC18222 => FGC18226 => FGC18218 => YP1385 => YP4487).

4. There are a significant number of shared deviations from the R1a-Y2619 Ashkenazi Levite modal value on markers 112 through 561 on men who belong to the R1a-BY29826 cluster.

First, FTY1006=12 (marker no. 559) (the R1a-Y2619 Ashkenazi Levite modal value is FTY1006=11) is, when reported, shared by all of the men who are reported by Big Y as being BY29826+ and by all but one of the men who are reported by Big Y as belonging to the R1a-Y2619* cluster.

Second, DYS508=12 (marker no. 186) (the R1a-Y2619 Ashkenazi Levite modal value is DYS508=11) and FTY44=12 (marker no. 516) (the R1a-Y2619 Ashkenazi Levite modal value is FTY44=11) are shared by four of the five tested BY29826 men who do not belong to the R1a-YP3939 subcluster (i.e., R1a-BY29826 => YP3939) (and by two of the three R1a-Y2619* men for whom BY29826 was not read on their Big Y results).

Third, the following five marker values are shared by the three men who belong to the R1a-YP3939 subcluster: (a) FTY191=11 (marker no. 261) (the R1a-Y2619 Ashkenazi Levite modal value is FTY191=12); (b) DYS523=14 (marker no. 438) (the R1a-Y2619 Ashkenazi Levite modal value is DYS523=15); (c) FTY269=12 (marker no. 439) (the R1a-Y2619 Ashkenazi Levite modal value is FTY269=13); (d) DYS543=12 (marker no. 506) (the R1a-Y2619 Ashkenazi Levite modal value is DYS543=13); and (e) FTY1025=13 (marker no. 530) (the R1a-Y2619 Ashkenazi Levite modal value is FTY1025=14).

Fourth, some of the men in the R1a-BY29826 cluster who are not part of the R1a-YP3939 subcluster have FTY445=12 (the R1a-Y2619 Ashkenazi Levite modal value is FTY445=11).

The results discussed above on FTY 1006 (marker no. 559), DYS508 (marker no. 186), and FTY44 (marker no. 516) tend to confirm that the men who have been reported by FTDNA as being R1a-Y2619* but without reported positive or negative results for BY29826 do, in fact, belong to the R1a-BY29826 cluster.

Conversely, such results also confirm that the remaining man reported as R1a-Y2619* does not belong to the R1a-BY29826 cluster, and that he instead belongs to a fourth R1a-Y2619* line – parallel to the R1a-Y2630, R1a-FGC18222, and R1a-BY29826 lines, and currently without an identified terminal SNP downstream from Y2619 – that has survived to the present day. [As discussed above, that line now has a terminal SNP - R1a-BY73299.]

5. In the 81 sets of results received as of May 12, 2018, the following STRs have mutated independently in separate R1a-Y2619 Ashkenazi Levite subclusters on at least three occasions, and therefore are likely of use only in refining relatively recent matches: (a) FTY394 (marker no. 119) (four mutations, three of them independent); (b) FTY 214 (marker no. 198) (seven independent mutations); (c) DYS569 (marker no. 239) (four independent mutations); (d) DYS542 (marker no. 255) (10 largely independent mutations); (e) FTY275 (marker no. 280) (three independent mutations); (f) FTY285 (marker no. 284) (at least six independent mutations); (g) FTY112 (marker no. 382) (at least five independent mutations); (h) DYS551 (marker no. 389) (at least four independent mutations); (i) DYS516 (No. 433) (multiple independent mutations, several of which are shared by men in the same subcluster and that may therefore have genealogical significance as to those men); (j) FTY1016 (marker no. 498) (at least five independent mutations); and (k) DYS637 (marker no. 533) (at least five independent mutations).

6. There are also independent mutations on the following markers on which, as discussed above, the marker value on these markers is characteristic of an R1a-Y2619 Ashkenazi Levite subcluster: (a) FTY191 (marker no. 261) (six or seven independent mutations in addition to the mutation characterizing the R1a-YP3939 subcluster as discussed above); (b) FTY299 (marker no. 264) (three independent mutations, including the mutation characterizing the R1a-FGC36607 subcluster as discussed above); (c) FTY235 (marker no. 425) (at least four independent mutations, including the mutation characterizing the R1a-YP5304 subcluster as discussed above); (d) DYS523 (marker no. 438) (numerous independent mutations, including mutations that characterize the R1a-YP1386 subcluster, the R1a-FGC18222 cluster, and the R1a-YP3939 subcluster as discussed above); (e) FTY269 (marker no. 439) (seven independent mutations, including a mutation characterizing the R1a-YP3939 subcluster as discussed above); (f) DYS543 (marker no. 506) (at least nine independent mutations, including a mutation characterizing the R1a-YP3939 subcluster as discussed above); and (g) FTY1025 (marker no. 530) (at least three independent mutations, including a mutation characterizing the R1a-YP3939 subcluster as discussed above).