psychologist on staff who would be happy to see you whenever youâd like . . .â
âWhat am I supposed to do with my life now?â she blurted out. âWhat about college?â
âThat can be sorted out later. First, go home, talk to your family, spend some time taking this in.â
âAll I want to do is grow up,â she whispered. âThatâs all Iâve ever wanted.â
Dr. Carlyle faltered for a moment. âIâd be happy to schedule your first session withââ
She shook her head. âDo you think, if you study me, you could figure out a way to make me age?â
He smiled as if at a childâs amusing remark. âYou know, most people would ask the opposite.â
She was in no mood for irony. âCould you?â
âWell, if we can first learn whatâs stopping it in you, the goal would then be to manipulate the genes to turn them on or off at will. So itâs possible, but it could take a long time, a very long time.â
âCenturies?â
âMaybe not that long. Could be decades, unless some genius gets us there faster.â
âArenât you a genius?â
He smiled. âI donât specialize in aging research, but I have brilliant colleagues who do. They would want to sequence your entire genome.â
âWill it hurt?â
âNot much. Itâs only drawing blood.â
âAnd a genome is like all my genes together?â
âSorry, I should have explained.â He leaned back in his chair and folded his hands over his knee. âYes, your genome is the entirety of all the information youâve inherited, encoded in your DNA. At Columbia, I teach my students to think of a genome like a book. It has twenty-three chapters, which are your chromosomes, and in each chapter there are roughly forty-eight to two hundred fifty million letters. Those letters spell out all your genes, which determine your characteristics. The whole book fits into a cell nucleus the size of a pinpoint, and thereâs a copy of it in pretty much every cell in our bodies. So when we sequence a genome, we examine about ninety-eight percent of those three billion letters to see if we can find any unusual spellingsâany clues unique to your body at the molecular level.â
She took a deep breath. âI see,â she said. Though she didnât, not really. The scale was impossible to grasp. How could billions of letters fit into a single cell that you couldnât even see? Even though sheâd taken biology as a one-semester requirement in high school, the subject had never felt real or urgent until now. âSo,â she said, wanting desperately to understand, âyou think I have misspellings, right?â
âExactly, called mutations.â
âAndâand how would those affect your overall hypothesis? About the master gene?â
âThe master regulator gene,â he said, smiling. âWell, today, we think of genes as ripples in a pond, not as isolated entities. So if the master regulator gene was disrupted, it could set off mutations in other genes that affect aging, which could cause other mutations, and so forth. They can also just happen randomly. So finding mutations in you wouldnât necessarily prove my hypothesis. The key is to locate mutations that lead to the master regulator gene itself.â
âOkay,â she said. âI think that makes sense.â
He reached into his briefcase at the foot of the desk, pulled out a well-worn hardcover book, and handed it to her. On the bright blue cover were the swirly letters A, T, G, and C , and a title: The Genomics Age: How DNA Technology Is Transforming the Way We Live and Who We Are.
âItâs a primer I assign undergrads in Intro to Genetics,â he explained. âYouâre quite precocious, Zoe. Listen to me, donât underestimate yourself because of a number. Read this book and youâll get a better idea of