IPO8 and Hand-foot syndrome: Although we were not able to replicate the “true” SNP-gene associations for IPO8 in our replication sample, a set of different SNPs were indeed associated with IPO8 expression in HFs from frontal and/or occipital scalp areas, some of which were also associated with IPO8 expression in the discovery sample at the nominal level (data not shown), therefore confirming the genetic regulation of IPO8 in HFs.