Congenic mapping and genotyping of the tetrahydrobiopterin-deficient hph-1 mouse

The hph-1 ENU-mutant mouse provides a model of tetrahydrobiopterin deficiency for studying hyperphenylalaninaemia, dopa–response dystonia, and vascular dysfunction. We have successively localized the hph-1 mutation to a congenic interval of 1.6–2.8 Mb, containing the GCH gene encoding GTP cyclohydrolase I (GTP-CH I). We used these data to establish a PCR method for genotyping wild type, hph-1 and heterozygote mice, and found that heterozygote animals have partial tetrahydrobiopterin deficiency. These new findings will extend the utility of the hph-1 mouse in studies of GTP-CH I deficiency. [Copyright &y& Elsevier]