In comparison, around 200 response genes were linked with PIK3CA mutations, and fewer than 100 response genes were identified for the non-driver control gene TTN. The observation that the majority of response genes displayed a single breakpoint (Fig 1D) suggests that patient-derived GATA3 mutations can be divided into two functionally distinct regions and that mutations in these regions are associated with differential gene expression in tumours. Here, GATA3 is linked to neoplasm.