These findings replicate by QPCR and extend our earlier findings from genome-wide microarray studies that two Rho kinase pathway genes, ROCK1 [10] and Cofilin1 [11] are increased in HD leukocytes and suggest that some of these genes could be a useful source of peripheral markers of HD progression or of pharmacodynamic responses to treatments targeting it. Here, ROCK1 is linked to Huntington disease.