Major NIH Award Supports Epigenomics Research

By Jeffrey Norris

First there was the Human Genome Project, aimed at mapping all human DNA and understanding how the genetic code defines and controls genes. Now the federal government is sponsoring a big push to understand how another kind of biological code helps determine what we are. Just add to the word “genome” the prefix “epi” – as in beyond, or epic, if you prefer – and you come up with epigenome. The epigenome refers to the fact that beyond the chemical alphabet building blocks of the genetic code, there are other chemical modifications to DNA and its associated proteins that occur in meaningful, changeable patterns. These patterns guide development and determine, for instance, why a liver cell differs from a brain cell, even though the genetic code is essentially the same in every cell within any individual. The epigenome helps control which genes are switched on and off in particular cells, which in turn determines the cells’ identity and function. With the right cues, epigenomes can be reprogrammed to change adult cells to embryonic cells and vice versa. Researchers expect that gaining a better understanding of the epigenome is likely to lead to a better understanding of human diseases, including cancers and certain developmental and degenerative disorders. The National Institutes of Health (NIH) now has launched the $190 million NIH Roadmap Epigenomics Program, and on Monday announced four major awards. One of the largest, for up to $12 million over five years, goes to collaborating researchers from UCSF, UC Davis, UC Santa Cruz and the University of British Columbia (UBC) in Vancouver. The project, called Integrated Epigenetic Maps of Human Embryonic and Adult Cells, is led by Joseph F. Costello, PhD, associate professor of neurological surgery at UCSF, and is co-led by UBC scientist Marco Antonio Marra, PhD, who also heads the British Columbia Cancer Agency Genome Sciences Centre. “The epigenome is the dynamic interface between our changing environment and the static genome,” Costello says. “Understanding it is a goal of immense importance to human health.” Modifications to DNA and surrounding proteins, called histones, help determine which genes may be switched on in different cells. The epigenetic program that helps control gene switching may be altered by environmental chemicals, diet or even stress. Understanding patterns in how specific chemical modifications arise in proteins and DNA is the key to unraveling the epigenetic code and the aim of the collaborative effort.