RT-PCR–SSCP analysis of the

CHK2 gene. (A) The abnormal mobilities observed in the HCT15 cell line corresponded to the previously described missense mutations Ala247Asp (top) and Arg145Trp (bottom). (B) Case no. 825 (top) showed a distinct mobility shift that corresponded to an aminoacid substitution at codon 157 (ATT>ACT) leading to an Ile→Thr change. Case no. 266 (bottom) showed an altered mobility that was also found in 2 more lymphomas corresponding to a silent polymorphism at codon 84 (GAA>GAG).