Early in the 20th century, German biologist Hans Spemann separated two cells of a salamander zygote using a strand of his daughter’s hair. His experiment produced two fully formed amphibians, demonstrating that each cell contains the full genetic blueprint to build a living thing, not the partial instructions that scientists had previously supposed.
Why he used the child’s hair isn’t clear, science writer Kean notes, but “probably the baby’s hair was finer.”
In Kean’s history of DNA, each chapter is loosely organized to address questions about humans’ genetic past and future. He pays tribute to genetics’ key players and major milestones, including Watson and Crick, Mendel and the researchers who raced to draw up the human blueprint (“blitzkrieg sequencing,” Kean calls it) during the Human Genome Project.
But Kean’s real knack is for digging up strange details most textbooks leave out. So in addition to the great achievements, this is also the story of how scientists express artistic sides with sculptures crafted from DNA, what genetic disorders Darwin (and Lincoln, Kennedy and Tutankhamen) might have had and why a genetic adaptation in polar bears means it’s a bad idea for humans to snack on the bears’ livers. It’s also about violinist Niccolò Paganini and how his genes gave him both remarkably flexible hands and medical issues that left him unable to perform.
More than an assortment of trivia, the book is an engaging history. After all, Kean quips, “the story of DNA has effectively replaced the old college Western Civ class as the grand narrative of human existence.”
Little, Brown & Co., 2012, 317 p., $25.99