Tracy Hutchinson, from a family originally of Hounslow, west London who emigrated to New Zealand, has learned she carries Li-Fraumeni syndrome, a rare mutation of the TP53 gene that leaves her with a 100% lifetime chance of developing cancer. The tumour-suppressing gene, which normally helps control cell growth and division, is faulty in Tracy's case, meaning her body lacks a key defence against the disease. The diagnosis follows decades of tragedy in her family, beginning when her elder sister Rebecca developed acute lymphoblastic leukaemia at 21 and later died despite a bone marrow transplant from Tracy, with cancer subsequently striking other family members too.

Rather than finding the news frightening, Tracy, now 50, says it has brought her clarity after years of unexplained family suffering, telling how she is "surprisingly at peace" now she finally has an answer. Li-Fraumeni syndrome was only being identified by scientists in the 1980s, around the time Rebecca first fell ill in 1990, and the Hutchinson family has since lost several members to cancer as the genetic link became clear. Tracy says living with certainty about her condition has made her more appreciative of the moments in her life.