An integrated genetic linkage map with 1137 markers constructed from five F2 crosses of autoimmune disease-prone and -resistant inbred rat strains

The rat (Rattus norvegicus) is an important experimental model for many hum an diseases including arthritis, diabetes, and other autoimmune and chronic inflammatory diseases. The rat genetic linkage map, however, is less well developed than those of mouse and human. Integrated rat genetic linkage map s have been previously reported by Pravenec ef al. (1996, Mamm. Genome 7: 1 17-127) (500 markers mapped in one cross), Bihoreau et al. (1997, Genome Re s. 7: 434-440) (767 markers mapped in three crosses), Wei ef al. (1998, Mam m. Genome 9: 1002-1007) (562 markers mapped in two crosses), Brown et al. ( 1998, Mamm. Genome 9: 521-530) (678 markers mapped in four crosses), and No rdquist ef at (1999, Rot Genome 5: 15-20) (330 markers mapped in two crosse s). The densest linkage map combined with a radiation hybrid map, reported by Steen ef al. (1999, Genome Res. 9: AP1-AP8), includes 4736 markers mappe d in two crosses. Here, we present an integrated linkage map with 1137 mark ers. We have constructed this map by genotyping F2 progeny of five crosses: F344/NHsd x LEW/NHsd (673 markers), DA/Bkl x F344/NHsd (531 markers), BN/S sN x LEW/N (714 markers), DA/Bkl x BN/SsNHsd (194 markers), and DA/Bkl x AC I/SegHsd (245 markers). These inbred rat strains vary in susceptibility/res istance to multiple autoimmune diseases and are used extensively for many t ypes of investigation. The integrated map includes 360 loci mapped in three or more crosses. The map contains 196 new SSLP markers developed by our gr oup, as well as many SSLP markers developed by other groups. Two hundred fo rty genes are incorporated in the map. This integrated map should allow com parison of rat genetic maps from different groups and thereby facilitate ge netic studies of rat autoimmune and related disease models. (C) 2000 Academ ic Press.