To assess this, we generated plasmids containing multiple gRNAs driven by three distinct zU6 promoters (zU6A, zU6B, and zU6C) to simultaneously target both tumor suppressors (tp53, ptena/ptenb) and tumor-promoting genes (sox10) in the same cells, which reduces the chance of selecting for non-mutant alleles (Yin et al., 2015). The gene discussed is SOX10; the disease is neoplasm.