A loxP site flanked neomycin resistance gene was inserted into intron 8 and an A-to-G point mutation was created at position 1249 (GenBank M24119) in exon 9 causing an N-to-S amino acid substitution at residue 388 (370 in mature protein) (p.N388S). The neo cassette was then removed through subsequent Cre-mediated recombination. (J:86334)