Missense mutation engineered by CRISPR removes a selenocysteine to place a stop codon. Resistance to cisplatin exposure. Primers to genotype the cer55 and other silent mutations: [Common Fw: #1224 GGCTTCCACATTCTCACTCC] [RV wildtype: #1414 cTTAACCTCAGCAACCAGAA] [RV Sec to STOP: #1421 CTTAACCTTAACATCCGCTG] Reference: García-Rodríguez FJ, et al. Dis Model Mech. 2018 Jun 21;11(6).