Correction of ornithine transcarbamylase (OTC) deficiency in spf-ash mice by introduction of rat OTC gene.

We introduced rat ornithine transcarbamylase (OTC) gene into OTC-deficient spf-ash mice by mating spf-ash heterozygotes with transgenic mice which carried recombinant DNA composed of 1.3 kb of the 5' flanking region of the gene fused onto rat OTC cDNA. The liver OTC activity of hemizygous spf-ash mice which carried the transgene was about twice that of nontransgenic spf-ash mice, and the small intestinal OTC activity was 6 times higher; the values being 12% and 27% of the control levels, respectively. The transgenic spf-ash mice showed normal hair growth without sparse fur, nearly normalized urinary orotic acid excretion and normalized serum citrulline concentration.