AN INTEGRATED GENETIC-MAP OF THE PEARL LOCUS OF MOUSE CHROMOSOME-13

We have used a Mus domesticus/spretus congenic animal and two interspe cific backcross panels to map genetically 30 sequence-tagged sites (ST Ss) and 13 genes to the vicinity of the pearl locus on mouse chromosom e 13. The STSs defining the mapped region are from D13Mit9 to D13Mit37 , spanning 10.6 cM. Genes mapped to this region include Versican (Cspg 2), GTPase activating protein (Rasa), dihydrofolate reductase (Dhfr), arylsulfatase (As-1), thrombin receptor (Cf2r), hexosaminidase b(Hexb) , 3-hydroxy-3-methylglutaryl coenzyme A reductase (Hmgcr), microtubule associated protein 5/lb (Mtap5), phosphodiesterase (Pde), phosphatidy linositol 3' kinase (Pik3r1), rat integrin a1-subunit (Itga1), collage n receptor a2-subunit (Itga2), and S-hydroxytryptamine la receptor (Ht rla). This high resolution genetic map of the pearl region of chromoso me 13 establishes the order of multiple markers, including genes whose human homologs are located within a limited region of human chromosom e 5, with respect to the phenotypic anchor marker pearl.