Functional genomics of breast cancer and its biological and clinical implications. His laboratory redefined the molecular taxonomy of breast cancer. He also co-lead seminal studies that define the clonal heterogeneity of triple negative breast cancers and the patterns of whole-genome ER binding in primary tumours. His group led the studies that established ctDNA as a monitoring biomarker in breast cancer and as a liquid biopsy to unravel therapy resistance. More recently his laboratory has developed and pioneered the use of patient-derived tumour explants as a model system for breast cancer.