He’d been working with HeLa cells daily his whole career, he said, and now he couldn’t get the story of Henrietta and her family out of his mind. As a Ph.D. student, he’d used HeLa to help develop something called fluorescence in situ hybridization, otherwise known as FISH, a technique for painting chromosomes with multicolored fluorescent dyes that shine bright under ultraviolet light. To the trained eye, FISH can uncover detailed information about a person’s DNA. To the untrained eye, it simply creates a beautiful mosaic of colored chromosomes.
