"A Frances Coady book."

Russell Stone, a Chicago writing instructor, discovers in his Berber Algerian student, Thassadit Amzwar, a preternatural happiness that has earned her the nickname "Miss Generosity." Stone soon learns that Thassadit may possess a rare euphoric trait called hyperthymia, and that Thomas Kurton, the charismatic entrepreneur behind genetics lab, Truecyte, wants to use her alleles to deliberately "adjust" the genome to produce happier, longer-living people with less disease.