The Wilms tumour gene WT1 in leukaemia

The WT1 gene is essential for kidney development and is mutated in some Wilms tumours. It is also expressed at a high level in many acute leukaemias and in some haematopoietic progenitor cells, and mutations have been found in leukaemias. The function of WT1, which is a zinc finger protein and has domains characteristic of transcription factors, is not well understood. The level of expression is highest in leukaemias with immature phenotypes. Expression of WT1 is downregulated during differentiation of leukaemic cell lines and high levels of WT1 expression can cause cell cycle arrest and/or apoptosis. This may reflect a role in the control of normal haematopoiesis, which can be abrogated by mutations in the gene and form part of the pathway towards leukaemogenesis.