A targeting vector was designed with an SV40 splice acceptor, a loxP-flanked STOP cassette (PGK-neo and triple SV40 transcriptional termination sequence), a human alpha-synuclein cDNA bearing a familial Parkinson's disease-linked A53T missense mutation (SYNA53T), and a bovine polyadenylation signal. (J:147332, J:150777)