The baseline time span for this database is (publication years)
1998-December 31, 2008 from the sixth bimonthly update (an 11-year period).
The resulting database contained 11,184 (10 years) and 4,246 (2 years)
papers; 33,541 authors; 97 nations; 1,772 journals; and 4,877 institutions.
See additional paper information below in the overview & methodology
sections.
Interviews, first-person essays, and profiles about
people in a wide variety of fields which pertain to
this special topic of Epigenetics.
OVERVIEW
Epigenetics is a term with a long history, but today it refers to the
heritable changes in phenotype or gene expression that do not come from an
alteration in DNA structure or sequence. The field focuses on organism
development, origins of cancer, evolution, and the potential for medical
applications. This month, ScienceWatch.com takes a look at the
literature on epigenetics over the past decade and over the past two years.
The search strategy was a simple one: a keyword (title, abstract, keywords)
search of original articles and review papers for the term "epigenet*." The
baseline time span for this analysis was January 1, 1998-December 31, 2008
(sixth bimonthly period 2008). The resulting database contained 11,184
papers based on a 10-year extraction and 4,246 papers published over the
past two years. To create a more on-point list of the top 20 papers for the
past decade and the past two years, the papers were further narrowed down
by the title keyword "epigenet*." This adjustment resulted in the top 20
papers being selected from a pool of 2,510 papers (10 years) and 1,022
papers (2 years).
The role of epigenetics in cancer is a major focus of the top papers from
the last 10 years, with particular emphasis on the mechanism of DNA
methylation. Two papers also deal with epigenetic alterations in the RAS
domain family protein in the development of lung and breast cancers. The
role of histone methylation in heterochromatin assembly control is also
addressed, as well as epigenetic memory, environmental effects, chromatin
modification, mammalian development, therapeutic prospects, and the
epigenetic stability (or lack thereof) in embryonic stem cells and cloning.
Topics covered in the more recent papers include epigenetics in psychiatric
disorders, epigenetic silencing of microRNA, the potential for a stem cell
origin in cancer, the regulation of mammalian telomeres, epigenetics in
plants, phenotypic plasticity, histone modifications, and epigenetic memory
in malaria virulence genes.
Methodology: The baseline time span for
this database is (publication years) 1998-December 31, 2008 from
the sixth bimonthly update (an 11-year period). The resulting database
contained 11,184 (10 years) and 4,246 (2 years) papers; 33,541 authors;
97 nations; 1,772 journals; and 4,877 institutions. See additional paper
information below in the overview & methodology sections.
Papers: To construct the top 20 papers lists for the past
decade and the past two years, the papers were further narrowed down by the
title keywords "epigenet*." This adjustment resulted in the top 20 papers
being selected from a pool of 2,510 papers (10 years) and 1,022 papers (2
years).
Rankings: Once the database was in place, it was used to
generate list of authors, journals, institutions, and nations. Rankings for
author, journal, institution, and country are listed in three ways:
according to total cites, total papers, and total cites/paper. The paper
thresholds and corresponding percentages used to determine scientist,
institution, country, and journal rankings according to total cites/paper,
and total papers respectively are as follows: