INTS13 and neoplasm: An F2 intercross mapping study using the SWXJ RI parental strains SWR and SJL confirmed significant linkage of GC tumor susceptibility with SWR alleles at Gct1 on Chr 4, along with Gct2 on Chr 12, Gct3 on Chr 15, and Gct5 on Chr 9, and confirmed the modifier influence of SJL alleles at Gct4 on Chr X (Beamer et al. 1998).