IFG, GLI, MDM1, MDM2, AND MDM3 - CANDIDATE GENES FOR THE MOUSE PG LOCUS

Various genes that mapped to the distal end of Chromosome (Chr) 10 wer e considered as possible candidates for the mouse pygmy (pg) locus. Pr obes derived from Ifg, Gli, Mdm1, Mdm2, and Mdm3 (Mdm2 and Mdm3 are ge nes that are coamplified with Mdm1 on the same double minute chromosom es in 3T3DM cells) were used for Southern analysis of DNA from wild-ty pe mice and various pg mutants. In addition, the chromosomal locations of Ifg, Gli, Mdm1, Mdm2, and Mdm3 were determined by interspecific ba ckcross analysis with progeny derived from matings of [(C57BL/6J X Mus spretus)F-1 X C57BL/6J] mice. The mapping data indicate that the Mdm loci are linked to each other and to Ifg, pg, and Gli in the distal re gion of mouse Chr 10. Both the mapping data and the Southern analysis confirm that Mdm1, Mdm2, Mdm3, Ifg, and Gli are distinct from pg.