The transgene comprises 12.3 kb of human genomic DNA containing the GPD1 gene, consisting of 3.5 kb of 5' flanking sequence, the 7.6 kb protein-coding region and 1.2 kb of 3' flanking DNA. The 5' flanking sequence includes the proximal and distal promoter regions. Founder line A1 has approximately 6 copies of the transgene. Mice exhibit a much higher level of transgene expression in the cerebral cortex than is normal for the endogenous gene. (J:135002)