The resulting list of institutions shows that epigenetics is of international interest, and extends from universities to government organizations and the private sector. Fourteen of the institutions are US-based, four hail from the UK, and one is from Austria.

Johns Hopkins University tops the list, with 347 papers cited a total of 21,385 times—over 10,000 more citations than the next institution on the list. Their ranking comes as no surprise when one sees that the top two slots on our scientists listing belong to Johns Hopkins researchers Stephen Baylin (see also) and James Herman. More than half of the citations for Johns Hopkins are due to these scientists, both of whom have talked with ScienceWatch.com in the past about their work.

Coming in at #2 is Harvard University, with 307 papers cited a total of 10,614 times. Epigenetic control of gene expression, epigenetics in mammalian development, and epigenetics in cancer are just a few of the topics from Harvard's researchers that are being cited.

The National Cancer Institute of the US claims the third spot, with 284 papers cited a total of 8,250 times. Shiv Grewal's papers on DNA methylation and heterochromatin are among the top-cited papers for this institution. Other hot research areas include cancer pathogenesis, the role of DNA methylation in health and disease, and tumor phenotypes.

The #4 slot belongs to the University of Southern California, with 114 papers cited 7,355 times. USC's top two papers, with cites in excess of 1,000 each, have as their lead author Peter Jones. He and Johns Hopkins coauthor Stephen Baylin spoke with ScienceWatch.com about their paper, "The fundamental role of epigenetic events in cancer," (Nat. Rev. Genet. 3[6]: 415-28, June 2002). This paper is ranked #1 in our Topic.

Ranking fifth is the University of Virginia, with 45 papers cited 6,588 times. Among Virginia's highly cited papers are such topics as the histone code, chromatin structure, and histone-chromatin crosstalk.

Placing at #6 is the first of four UK-based organizations: the University of Cambridge with 155 papers cited a total of 5,676 times. Cambridge's highly cited work centers on epigentics in cancer and other diseases, such as diabetes, Beckwith-Wiedemann syndrome, and Huntington's disease, and the role of epigenetics in cells, particularly in mammalian development.

The list returns to the US with the institution ranked at #7: MIT, with 87 papers cited 5,573 times. More than half of these citations have their origins in the research of Rudolf Jaenisch, whose work on the role of epigenetics in stems cells, among other things, has earned him the #8 slot on our list of the top 20 scientists by total citations. This month, ScienceWatch.com spoke with him about his work.

Coming in at #8 is the Vienna Biocenter, with 25 papers cited 5,424 times. The Biocenter's profile has been helped a great deal by the work of Thomas Jenuwein, although he has since moved to the Max Planck Institute of Immunobiology in Germany. Another researcher coming out of the Vienna Biocenter is Jan-Michael Peters, whose work focuses on mitotic issues, such as sister chromatid cohesion, the anaphase promoting complex/cyclosome, and mitotic kinases.

The #9 slot belongs to the University of California, San Francisco, with 146 papers cited a total of 5,286 times. Cancer epigenetics appears to be the main focus of the research groups at UCSF, and includes such topics as tumor expression and using epigenetics to develop anticancer agents.

Rounding out the top 10 is the UK's Babraham Institute, with 81 papers cited a total of 5,285 times. Mammalian development, particularly the parental influence on the genome, is a large part of the highly cited research for this registered charity organization. Wolf Reik, whose work earned him the #7 spot on our list of top-cited scientists in epigenetics, and who spoke with ScienceWatch.com about his work some years ago, hails from the Babraham Institute.

The remaining institutions on the list include eight from the US—one more from California (the University of Los Angeles, CA, at #11), one each from Pennsylvania (the University of Pennsylvania at #12), Missouri (Washington University in St. Louis at #15), New York (Cold Spring Harbor Lab at #16), Ohio (Ohio State University at #18), and Washington (the University of Washington at #19), and two from Texas (the University of Texas Health Science Center in Houston at #17 and the University of Texas Southwestern Medical Center at #20). The remaining institutions on the list are based in the UK: the University of Edinburgh at #13 and the University of Birmingham at #14.

The full list of the top 20 institutions in epigenetics by total cites is as follows:

Keywords: EPIGENETICS, EPIGENETIC EVENTS, CANCER, DNA METHYLATION, EPIGENETIC MEMORY, GENE EXPRESSION, DNA HYPERMETHYLATION, TUMORIGENESIS, HISTONE, GENETICS, TUMOR SUPPRESSOR, MAMMALIAN DEVELOPMENT, EPIGENETIC THERAPY, EPIGENETIC CODE, HETEROCHROMATIN, PHENOTYPE SUPPRESSION, EMBRYONIC STEM CELLS, FIBROBLASTS, PLURIPOTENCY, POLYCOMB, TRITHORAX, TELOMERES, MICRORNA, REGULATORY T CELLS.