β-Catenin Is Dispensable for Hematopoiesis and Lymphopoiesis

� -catenin‐mediated Wnt signaling has been suggested to be critically involved in hematopoietic stem cell maintenance and development of T and B cells in the immune system. Unexpectedly, here we report that inducible Cre-loxP‐mediated inactivation of the � -catenin gene in bone marrow progenitors does not impair their ability to self-renew and reconstitute all hematopoietic lineages (myeloid, erythroid, and lymphoid), even in competitive mixed chimeras. In addition, both thymocyte survival and antigen-induced proliferation of peripheral T cells is � -catenin independent. In contrast to earlier reports, these data exclude an essential role for � -catenin during hematopoiesis and lymphopoiesis.