Corrigendum Kun-hsian Liu, Massachusettes general hospital 25 May 2012 A critical reference was omitted in the Background section of this article. A paper by Schneeberger et al. on SHOREmap should have been cited along with references 7-9 in the second paragraph in the Background section. Reference: Schneeberger K, Ossowski S, Lanz C, Juul T, Petersen AH, Nielsen KL, Jorgensen JE, Weigel D, Andersen SU: SHOREmap: simultaneous mapping and mutation identification by deep sequencing. Nat Methods 2009, 6(8):550-551. We apologize to readers for this mistake. Competing interests The authors declare that they have no competing interests.