The transgene contains a portion of human BAC clone (CTD-2149o15, Invitrogen) including the entire APOA1 gene as well as 6.3 and 3.7 kb of 5' and 3'-flanking regions, respectively. Site-directed mutagenesis altered all four tryptophan residues to phenylalanine resulting in the 4WF isoform. (J:304480)