Correction to: Nature https://doi.org/10.1038/nature13848 Published online 26 October 2014

In the version of the article initially published, there was an error in Extended Data Fig. 6 where panel g was a duplicate of panel k. The corrected Extended Data Fig. 6g is shown below as Fig. 1.

Fig. 1: Corrected Extended Data Fig. 6g
figure 1

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