The three Idd4 sub-loci have been mapped to Chr. 11. Chr. 11 genomic segments from C57BL/6 were transferred to NOD by outcross to an NODxC57BL/6J F2 mouse followed by 3 backcross cycles to NOD/Del with selection for B6 markers on Chr. 11 prior to inbreeding. T.L.Delovitch established three congenic strains based on their congenic intervals, D11Nds1-D11Mit325 (43.8-49cM), D11Mit38-D11Mit325 (49cM) and D11Mit38 (49cM). The 5.2cM region located between D11Nds1 - D11Mit325 of Chr. 11 is known to contain Nos2 (45.6cM) Mpmv4 (48cM), Xmv42 (53cM), Mpo, (49cM, D11Mit38) and the beta-chemokine gene family, including, Ccl1 (Tcr3, 47cM), Ccl2(Mcp1, 46.5cM), Ccl3 (Mip1a, 47.59cM), Ccl4 (Mip1b, 47.6cM) (Gill et al, 1995 and Grattan et al, 2002). Additional microsatellite analysis confirm all currently known Idd's are NOD in origin. (Grattan, et al., 2002). In 2005, The Jackson Laboratory received NOD.B6-(D11Mit38)/DelJ (NOD.Idd4C) at generation N3F19.
Genetic Quality Control completed at the Jackson Laboratory indicates the following Chromosome 11 markers are of B6 origin: D11Mit38 (49cM) and D11mit41 (49cM), while D11Mit325 (31.7cM) and D11Mit358 (52.5cM) are of NOD origin. Surprisingly, Chromosome 1 markers (Idd5 region) of B6 origin include: D1Mit180 (41cM), D1Jmp12 (47-51.4cM), D1Jmp23 (54.6cM), D1Mit445 (70cM), and D1Mit143 (86.6cM); while D1Mit18 (27 cM) and D1Mit26 (62.1cM) and D1Mit36 are of NOD origin.
