Progenitors of the CALB/Rk strain were originally trapped in California by Dr Richard Sage. Descendants of these mice were imported to The Jackson Laboratory from Dr Verne Chapman's colony in 1984 (TH Roderick, personal communication; Akeson and Davisson 1991). Sequence data has determined that in addition to Mus musculus domesticus, CALB/RkJ has haplotypes related to Mus musculus castaneus on at least five regions located in three different chromosomes. CALB/RkJ is believed to be a hybrid of the two species (Ideraabdullah FY, et al. 2004).

• Petkov PM; Cassell MA; Sargent EE; Donnelly CJ; Robinson P; Crew V; Asquith S; Haar RV; Wiles MV. 2004. Development of a SNP genotyping panel for genetic monitoring of the laboratory mouse. Genomics 83(5):902-11PubMed: 15081119MGI: J:89298