HIGH-RESOLUTION MAPPING OF A LINKAGE GROUP ON MOUSE CHROMOSOME-8 CONSERVED ON HUMAN-CHROMOSOME 16Q

We have performed a high-resolution linkage analysis for the conserved segment on distal mouse Chromosome (Chr) 8 that is homologous to huma n Cbr 16q. The interspecific backcross used involved M. m. molossinus and an M. m. domesticus line congenic for an M. spretus segment from C hr 8 flanked by phenotypic markers Os (oligosyndactyly) and e, a coat colormarker. From a total of 682 N-2 progeny, the 191 animals revealin g a recombination event between these phenotypic markers were typed fo r 23 internal loci, The following locus order with distances in cM was obtained: (centromere)-Os-4.1-Mmp2-0.2-Ces1,Es1, Es22-1.2-Mtl,D8Mit15 -2.2-Got2, D8Mitl1-3.7-Es30-0.3-Es2, Es7-0.9-Ctral,Lcat-0.3-Cdhl, Cadp , Nmor1, D8Mitl2-0.2Mov 34-2.5-Hp.Tat-0.2-Zfp4-1.6-Zfpl,Ctrb0-10.9-e. In a separate interspecific cross involving 62 meioses, Dpep1 was mapp ed together with Aprt and Cdh3 at 12.9 cM distal to Hp. Tat, to the vi cinity of e. Our data give locus order far markers not previously reso lved, add Mmp2 and Dpep1 as new markers on mouse Chr 8, and indicate t hat Ctral is the mouse homolog for human CTRL. Comparison of the order of 17 mouse loci with that of their human homologs reveals that locus order is well conserved and that the conserved segment in the human a pparently spans the whole long arm of Chr 16.