SCIENTIFIC CORRESPONDENCE

trast, we found no significant difference in Y chromosomes of Jewish priests the distribution of alleles for the non-Y­ chromosome locus polymorphism D1S191 SIR - According to biblical accounts, the than paternal descent by which male (data not shown). These Y-chromosome Jewish priesthood was established about are assigned to the priesthood. Identifica­ haplotype differences confirm a distinct 3,300 years ago with the appointment of tion as a priest carries with it certain social paternal genealogy for Jewish priests. the first Israelite high priest. Designation and religious obligations which have tend­ We further identified subjects as being of Jewish males to the priesthood con­ ed to preserve this identity within Jewish of Ashkenazic or Sephardic origin. This tinues to this day, and is determined by communities. Based on surveys of Jewish refers to the two chief, separate communi­ strict patrilineal descent. Accordingly, we cemetery gravestones, priests represent ties which developed within the diaspora sought and found clear differences in the approximately 5% of the estimated total during the past millennium9• As shown in frequency of Y-chromosome haplotypes male world Jewish population of roughly the table, the same haplotype distinction between Jewish priests and their lay 7 million (data not shown). can be made between priests and lay counterparts. Remarkably, the difference We identified haplotypes of 188 unre­ members within each population. This is observable in both the Ashkenazic lated Y chromosomes using the poly­ result is consistent with an origin for the and Sephardic populations, despite the merase chain reaction (PCR) applied to Jewish priesthood antedating the division geographical separation of the two genomic DNA isolated from buccal of world Jewry into Ashkenazic and communities. mucosa! swab samples from Israeli, North Sephardic communities, and is of particu­ The human Y chromosome has useful American and British Jews. We construct­ lar interest in view of the pronounced properties for studies of molecular evolu­ ed haplotypes using first, the presence or genetic diversity displayed between the tion1·2. Except for the pseudo-autosomal absence of the Y Alu polymorphic (YAP) two communities9• This conclusion is fur­ region, it is inherited paternally and does insert, thought to represent a unique evo­ ther supported by the relative preponder­ not recombine. It can be used to construct lutionary event dated to between 29,000 ance of the YAP-, DYS19B haplotype in patrilineal genealogy cladograms comple- and 340,000 years ago 15; and second, a both populations, suggesting that this may have been the founding modal haplotype HAPLOTYPE FREQUENCY F(standard error) of the Jewish priesthood. All Ashkenazic Sephardic Taken together, our findings define a Alleles Cohen Israelite Cohen Israelite Cohen Israelite set of Y chromosomes of recent common n=68 n=120 n=44 n=81 n=24 n=39 origin. Differences which have accumulat­ YAP- DYS19 A 0.162 0.091 0.205 0.074 0.083 0.129 ed·in the genomic DNA of the Y chromo­ (0.045) (0.026) (0.061) (0.029) (0.056) (0.054) somes of Jewish priests during the B 0.544 0.325 0.454 0.321 0.709 0.333 relatively short time since the establish­ (0.060) (0.042) (0.075) (0.052) (0.093) (0.075) ment of the priesthood, should be useful C 0.162 0.300 0.227 0 .272 0.042 0.359 in defining rates and mechanisms of Y­ (0.045) (0.042) (0.063) (0.049) (0.041) (0.077) chromosome evolution. D 0.088 0.083 0.091 0.111 0.083 0.026 Karl Skorecki (0.035) (0.024) (0.044) (0.035) (0.056) (0.024) Sara Selig Shraga Blazer E 0.029 0.017 0.000 0.025 0.083 0.000 (0.020) (0.012) (0.017) (0.056) Bruce Rappaport Faculty of Medicine and Research Institute and YAP+ DYS19 0.015 0.184 0.023 0.197 0.000 0.153 Rambam Medical Centre, (all) (0.014) (0.035) (0.024) (0.045) (0.057) Technion- Institute of Technology, P x2 <0.001 <0.01 <0.01 Haifa 31096, Israel Ashkenazic, Jewish communities of northern Europe; Sephardic, Jewish communities of north and Department of Medicine, Africa and the Middle East; Cohen, Priest; Israelite, lay . A-E, different DYS19 haplotypes. University of Toronto, Toronto M5S1AB, Canada mentary to those formulated using mater­ polymorphic GATA repeat microsatellite, email: [email protected] nally inherited mitochondrial DNA. DYS19 (refs 6, 7). We also typed a subset Robert Bradman The phenotypic differences that exist of samples for the non-Y-chromosome Neil Bradman between different communities of con­ CA-repeat polymorphism, D1S191 (ref. 8). P. J. Waburton temporary Jews in the world are thought We determined the designation of each Monica lsmajlowicz to emanate, at least in part, from genetic subject as a member of the priesthood by Department of Biology, admixture with neighbouring communi­ direct questioning. Subjects who were not University College , ties of non-Jews, during a prolonged dis­ sure of their designation or who identified London WC1E 6BT, UK persion3.4. The genetic basis of this themselves as 'Levite' ( a separate junior Michael F. Hammer diversity has been investigated using priesthood, based on a different, less-well­ Laboratory of Molecular Systematics and analysis of neutral DNA markers, includ­ defined patrilineal lineage) were not Evolution, ing mitochondrial and Y-chromosome included in the current analysis. Biosciences West, University of Arizona, markers4 • However, previous studies have We identified six haplotypes, whose Tucson, Arizona 85721, USA not considered the subsets of male Jews frequencies are shown in the table (YAP­ 1. Hammer, M. F. Nature 378, 376-378 (1995). comprising the priesthood (Cohanim). DYS19A-E and YAP+ DYS19, all alle­ 2. Jobling, M.A. & Tyler-Smith, C. Trends Genet. 11, 2 449-456 (1995). Significantly, there is no procedure other les). Applying the x test to the frequen­ 3. Benerecetti, A. S. S. et al. Genetic Diversity Among Jews cies of the Y-chromosome haplotypes (eds Bonne-Tamir, A. & Adam , A.) 45-50 (Oxford Univ. distinguishes priests from the lay popula­ Press, New York, 1992). Scientific Correspondence 4. Ritte, U. et al. J. Mo/. Evo/. 37, 435-440 (1993). tion. The most striking difference was in 5. Hammer. M. & Horai, S. Am. J. Hum. Genet. 56, Scientific Correspondence is intended to the frequency of YAP + chromosomes 951-962 (1995). readers may 6. Santos, F. R. et al. Hum. Genet. 97, 309-313 provide a forum in which with lay Jews. raise points of a scientific character. among priests compared (1996). Only 1.5% of Y chromosomes among 7. Roewer, L. et a/. Hum. Mo/. Genet. 5, 1029-1033 Priority will be given to letters of fewer (1996) . than 500 words and ten references. priests were YAP +, in comparison to a 8. Gya pay, G. et al. Nature Genet. 7, 246-249 (1994). frequency of 18.4% in lay Jews. In con- 9 . Mot ulsky, A.G. Nature Genet. 9, 99-101 (1995). 32 NATURE · VOL 385 · 2 JANUARY 1997