This pathway is a hallmark of the disease since H2AX-positive sites have been found in the striatum of HD human post-mortem brains and recapitulated in PC12 cells expressing a pathogenic fragment of mHtt, in HD striatal cell lines (STHdhQ111) and in the striatum of R6/2 mice (Anne et al., 2007; Illuzzi et al., 2009). This evidence concerns the gene H2AX and Huntington disease.