The Editor-in-Chief has retracted this article because of significant concerns regarding two figures presented in this work, which question the integrity of the data. After publication, a number of overlaps were detected within Figure 1 of this article, and some of the images in this figure appear to have been cropped to give the appearance of being different samples. Specifically:

• samples 2, 6, and 9 appear to be identical

• samples 3, 7, and 10 appear to be identical

• samples 5 and 8 appear to be identical

Also, in Figure 6, lines 17–20 seem identical to lines 9–12.

The Editor-in-Chief therefore no longer has confidence in the integrity of the data in this article.

All authors agree with this retraction.

The online version of this article contains the full text of the retracted article as Supplementary Information.