With the current excitement around the field of genomics, it’s easy to forget that genes are simply short sections of DNA and part of much larger structures called chromosomes. Chromosomes are composed of chromatin—intricately wound strands of DNA wrapped around proteins called histones—and are now known to play an equally important role in defining how organisms develop, function, and remain healthy.
Epigenetics, literally “above genetics,” is the study of environmental changes to the genome, above those that may occur at the level of our DNA. These changes include modifications to elements surrounding genes, such as histone proteins, or modification to the transcriptional elements that control gene expression. Unlike changes to the genes themselves, epigenetic changes are usually generation-specific; in other words, epigenetic changes are not usually passed from parent to child. This relatively new science has reshaped our understanding of both normal development and disease processes and is now influencing development of the next generation of therapies. The Intramural Research Program (IRP) is exploring epigenetics in a diversity of fields:
- Obesity: Epigenetic alterations to our genome have long been suspected to play a role in complex human diseases, such as obesity. Our researchers study how environmental factors may influence development of the disease.
- Clinical trials and drug development: IRP scientists study the role of epigenetic anti-cancer therapies across a range of tumors, with hopes that epigenetic therapies can target and “reprogram” abnormal cells, rather than killing both cancerous and normal cells as in standard chemotherapies.
- Public health: Diet and exposure to environmental chemicals throughout all stages of development can cause epigenetic changes that can turn on or off particular genes. Scientists in the IRP investigate how these elements adversely affect populations as a whole.
- Behavioral science: Epigenetic changes are involved in many diseases, including drug addiction and alcohol dependence. Understanding how environmental factors alter the genome could clear new paths to treating addiction disorders.
Cancer research has been profoundly altered by the discovery that genetic and epigenetic factors drive both cancer initiation and progression. IRP researchers keep both types of alteration in mind while designing new cancer therapies. The newly established NCI Center of Excellence in Chromosome Biology (CECB) brings together researchers with an interest in cancer epigenetics to share research findings across the intramural community and beyond.
Visit the Epigenetics Scientific Interest Group to learn more about chromosome biology and epigenetics.