The RMCE with the targeting vector introduced into the 3' UTR an inverted lox71/lox66-flanked CAG promoter driving ubiquitous expression of human cDNA with the amino acid substitution lysine for aspartic acid at position 17 (E17K; Open Biosystems 100067520), an IRES sequence and firefly luciferase (Luc2). (J:233376)