This issue, we ask "5 Questions" of Scott Holmes, associate professor of molecular biology and biochemistry. He received a three-year grant from the National Science Foundation (NSF) to support his research on epigenetic silencing of gene expression. Gene expression refers to the observable characteristics generated on a molecular level by a particular sequence of DNA or gene; epigenetic controls are essential in maintaining the specific patterns of gene expression that distinguish hundreds of distinct cell types in skin, muscles and other types of tissue. Epigenetic mechanisms also explain how humans can have more than 200 distinct cell types. Q: Professor Holmes,…