Gene of the month: BAP1.

The BAP1 gene (BRCA1-associated protein 1) is a tumour suppressor gene that encodes a deubiquitinating enzyme (DUB), regulating key cellular pathways, including cell cycle, cellular differentiation, transcription and DNA damage response. Germline BAP1 mutations cause a novel cancer syndrome characterised by early onset of multiple atypical Spitz tumours and increased risk of uveal and cutaneous melanoma, mesothelioma, renal cell carcinoma and various other malignancies. Recognising the clinicopathological features of specific BAP1-deficient tumours is crucial for early screening/tumour detection, with significant impact on patient outcome.