Genetic linkage analysis in recombinant inbred mice of P40, a putative clone for the high-affinity laminin receptor

Recombinant inbred (RI) mice were used to genetically map sequences of a 43-kDa protein, P40, that was originally identified as a high-affinity laminin receptor. More recent data have implicated this protein in development of the retina (Rabacchi et al. Development 109: 521-531, 1990), possibly via its proposed function in protein translation (G. Brawerman, personal communication). We have identified, in Southern blots, a set of P40-related sequences in BXD recombinant inbred mouse DNA. Ten restriction fragment length polymorphisms (RFLPs) segregate among the RI strains and display strain distribution patterns (SDPs) which are linked in varying degrees to previously typed loci on Chromosomes (Chrs) 1, 3, 6, 9, 11, 14, and 19. An intronic DNA probe from an incompletely processed P40 mRNA transcript overlaps with two of these loci mapping near the cholecystokinin gene locus on the distal arm of Chr 9 and to another site on the distal arm of Chr 6, suggesting that functional genes probably reside at least at these two sites. These P40 loci comprise part of a multimember gene family that is well dispersed in the mouse genome.