Sarabeckah Abraham Weiss is suffering from more than her share of middle-aged malaise. She has always felt subordinate to all the dynamic, high-achieving men in her life, and she has been unable to find fulfilling work of her own. Now separated from her controlling husband, she is longing for him, missing the strong physical relationship that had kept them together for years. She is also increasingly disturbed by elements in the lives of their two sons, who are away at graduate school, and she bears the bulk of responsibility for her mother, who has Alzheimer’s. Then, while sorting through her mother’s papers, Sarabeckah uncovers a secret that her parents had carefully hidden all of her life.

Everything she had thought she knew of her genetic makeup was false. None of the hereditary traits of the Abraham and Loewenthal families had ever applied to her. Whenever she had looked into a mirror to detect family resemblances, she was destined to fail; whenever she had filled out a doctor’s questionnaire, her answers were lies. All the things that people routinely know of their physical and mental propensities are mysteries to her.

But in the unexplored tangle of her chromosomes, there must be some valuable clues. She needs to explore them-but first she needs help to find them. Perhaps then she can dispel the nagging sense of incompleteness she has been feeling for years, a feeling only intensified on the day she discovered who she was not.