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Almost every cell in your body has the same DNA sequence. So how come a heart cell is different from a brain cell? Cells use their DNA code in different ways, depending on their jobs. Just like orchestras can perform one piece of music in many different ways. A cell's combined set of changes in gene expression is called its epigenome. This week Nature publishes a slew of new data on the epigenomic landscape in lots of different cells. Learn how epigenomics works in this video. Read the latest research on epigenetics at http://www.nature.com/epigenomeroadmap

The early stages of embryonic development shape our cells and tissues for life. It is during this time that our newly formed cells are transformed into heart, skin, nerve or other cell types. Scientists are finding that this process is largely controlled not by the genome, but by the epigenome, chemical markers on DNA that tell cells when to turn genes on and off. Now, studying zebrafish embryos, researchers at Washington University School of Medicine in St. Louis have shown that the epigenome plays a significant part in guiding development in the first 24 hours after fertilization.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome.

Almost every cell in the human body has the same DNA sequence. So why is a heart cell different from a brain cell? Cells use their DNA code in different ways, depending on their jobs - just as the orchestra in this video can perform one piece of music in many different ways. The combination of changes in gene expression in a cell is called its epigenome

Epigenomic fact sheet

In this audio slide show, Dr. Dana Dolinoy of Duke University explains the role that the epigenome, a sort of second genome, plays in regulating the expression of our genes. As Dolinoy notes, we can no longer say with certainty whether genetics or the environment have a greater impact on our health, because the two are inextricably linked through the epigenome.

In the August 1 issue of CELL, researchers from the Gene and Stem Cell Therapy Program at Sydney's Centenary Institute revealed another function of introns, or noncoding nucleotide sequences, in DNA. They reported that gene-sequencing techniques and computer analysis allowed them to demonstrate how granulocytes use noncoding DNA to regulate the activity of a group of genes that determines the cells' shape and function.

The study is the first to examine all of the gene networks affected by fructose that result in changes to brain function and metabolism-more than 20,000 genes in total. Although the study was conducted using rats, the researchers report that the majority of the sequenced genes are comparable to those in humans, including more than 200 genes in the hippocampus, a brain area crucial to memory, and 700 in the hypothalamus, the seat of the brain's metabolic control center.

Quick look: In its modern sense, epigenetics is the term used to describe inheritance by mechanisms other than through the DNA sequence of genes. It can apply to characteristics passed from a cell to its daughter cells in cell division and to traits of a whole organism. It works through chemical tags added to chromosomes that in effect switch genes on or off.

When you look at yourself in the mirror you may ask, 'How, given that all the cells in my body carry the same DNA, can my organs look so unlike and function so differently?' With the recent progress in epigenetics, we are beginning to understand. We now know that cells use their genetic material in different ways: genes are switched on and off, resulting in the astonishing level of differentiation within our bodies.

When are our genes most vulnerable? When can bad be good? Can epigenetics show us certain diseases are related?

After an exhaustive survey of contemporary epigenetics studies, one researcher has concluded that some of the effects of stress, cancer and other chronic diseases may be passed on to our offspring -- and theirs -- through deep and complicated underlying cellular mechanisms that scientists are just beginning to understand.

When Jordan is diagnosed with brain cancer (glioblastoma multiform), his college plans are unexpectedly put on hold. This scenario is presented in order to teach students about gene regulation, as the efficacy of the drug Jordan receives for post-surgical treatment is dependent upon the activity level of a gene encoding a protein involved in DNA repair. This "flipped" case study requires students to prepare in advance outside of class by watching several short videos that have been selected to teach the basics of how cancer forms as well as the role of epigenetics in gene silencing. Inside of class, the case is delivered using progressive disclosure format in which students gradually receive additional information to answer a series of directed questions. To determine a treatment plan for Jordan, students analyze data from a research study involving patients treated for his specific type of cancer. The case is designed for advanced high school biology classes as well as lower-level undergraduate general biology courses for non-majors and majors.

Graham Williams at the University of Huddersfield, UK, has a different way - to look for modifications to the twins' DNA that have come about as a result of their lifestyles. Such epigenetic changes occur when a chemical group known as a methyl group attaches to a gene and modifies the way it is expressed. This happens as a body is influenced by a person's environment, lifestyle and disease.

The laboratory-based animal study found a link between greater susceptibility to obesity and diabetes, and whether one's ancestors have been undernourished for several generations, and was published on Friday in the journal Cell Metabolism.