“the sins of the fathers may be visited on the deoxyribose nucleic acids of the sons”
There are almost as many metaphors for genes as there are genes. One of the most familiar, and the hardest to let go of, is the tidy blueprint, at once reassuringly clear and oppressively deterministic: Our genome is the architectural plan for who we are. It tells our body how to build itself, setting our height, our health, and even our moods since before we are born. Small wonder that we imagine if we can read our genome, we will discover not just the truth of ourselves but perhaps our future, too. Remember the high hopes that spurred on the Human Genome Project in the 1990s? Though the genetic catalog is now largely complete, we still await many of the anticipated insights, and in Epigenetics: The Ultimate Mystery of Inheritance, Richard Francis, a writer with a biology Ph.D., traces the emergence of a different genetic paradigm. Our DNA shapes who we are, Francis reports from the research forefront, but it is far from a static plan or an inflexible oracle; DNA gets shaped, too. For good or ill, the forces that determine our fate can’t be captured by anything so neat as a blueprint.