Call for a Large-scale Human Epigenome Project
: "Epigenetic modifications to DNA exert profound influences on gene activity. For example, studies suggest that epigenetic variation may be responsible for subtle differences in appearance and behavior of identical twins, whose gene activity profiles at 3 years of age are nearly alike, but by age 50 diverge as much as unrelated individuals in the population at large.
Epigenetic modifications take several forms. The most intensively studied have been the addition of methyl groups, small “beads” of carbon and hydrogen, to DNA, which generally correlate with low gene activity. The histone proteins – molecular “clips” that hold the six feet of DNA tightly wound inside each cell - are modified by methylation, but also by the addition of chemical entities containing acetic acid, phosphorus, and a number of other species.
The complex nature of epigenetic modifications constitutes a challenge to the development of reliable, high-throughput methods of cataloging them. Several workshop participants, however, working in both industrial and academic settings, have developed techniques proving adept at tackling epigenetic complexity.
These include the so-called ChIP/chip methodology, in which intact chromatin – the complex of DNA and histones – is immunoprecipitated (brought out of solution using antibodies that recognize specific histone modifications) and analyzed on microarray “chips.” Modifications of DNA are also tracked on chips, following treatment with enzymes that recognize sites of methylation."
Epigenetic modifications take several forms. The most intensively studied have been the addition of methyl groups, small “beads” of carbon and hydrogen, to DNA, which generally correlate with low gene activity. The histone proteins – molecular “clips” that hold the six feet of DNA tightly wound inside each cell - are modified by methylation, but also by the addition of chemical entities containing acetic acid, phosphorus, and a number of other species.
The complex nature of epigenetic modifications constitutes a challenge to the development of reliable, high-throughput methods of cataloging them. Several workshop participants, however, working in both industrial and academic settings, have developed techniques proving adept at tackling epigenetic complexity.
These include the so-called ChIP/chip methodology, in which intact chromatin – the complex of DNA and histones – is immunoprecipitated (brought out of solution using antibodies that recognize specific histone modifications) and analyzed on microarray “chips.” Modifications of DNA are also tracked on chips, following treatment with enzymes that recognize sites of methylation."