Transgenic mice were created in the laboratory of Dr. Robert E Hammer (University of Texas Southwestern Medical Center). The MMT-I-hLDLR transgene was designed with a 1.7 kb fragment of mouse metallothionein 1 gene (Mt1) promoter, a 2.6 kb cDNA of the human low density lipoprotein receptor (hLDLR) complete coding region (and 27 basepairs of 5' UTR), and the transcription termination signal from the human growth hormone gene. This transgene was microinjected into the male pronuclei of fertilized (C57/SJL)F2 hybrid mouse eggs, Founder mouse 93-4, with high hLDLR expression in the liver, was bred to establish the colony. These mice have 3 copies of the transgene inserted at a single site and express human LDLR mRNA.