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Stem cells

The road not taken

Developmental ‘road maps’ chart the steps from simple cells to mature, specialized cells. A newly discovered variety of blood-cell progenitor doesn't fit into the accepted blood map, but should that map be redrawn?

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Figure 1: Blood lines — cell-fate decisions of haematopoietic stem and progenitor cells.


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Hock, H., Orkin, S. The road not taken. Nature 435, 573–575 (2005).

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