The genes for adenylate kinase-1 (AK1), folyl polyglutamate synthetase (FPGS), the collagen pro alpha 1(V) chain (COL5A1), erythrocyte protein band 7.2b (EPB72), and a proto-oncogene homeobox (PBX3) all map to the distal portion of human chromosome 9q (HSA9q) but have not previously been mapped by linking analysis in the mouse. In this study, we have used two interspecific backcrosses to map the mouse homologues of each of these genes to mouse chromosome 2 (MMU2). The Ak1, Col5a1, Epb7.2, Fpgs, and Pbx3 genes were mapped with respect to the genes for Grp78, Rxra, Notch1 (the mouse homologue of TAN1), Spna2, Abl, and Hc (the mouse homologue of C5), all of which have previously been mapped by linkage analysis on MMU2 and have human homologues that map to HSA9q. Two of the reference loci for MMU2, D2Mit1 and Acra, were also mapped in the same cross to facilitate comparisons with existing maps. The consensus gene order deduced by combining data from both crosses is D2Mit1-(Dbh,Notch1)-(Col5a1,Rxra)-Spna2-Ab l-(Ak1,Fpgs)- (Grp78,Pbx3)-(Epb7.2,Hc,Gsn)-Acra. These loci therefore form part of the conserved synteny between HSA9q and MMU2.