p53 Pseudogene dating: identification of the origin of laboratory mice

Mutations were accumulated with a wide variety in the p53 pseudogene of various wild mouse species and subspecies captured at different localities, as extensively observed in the exon 4 - exon 5 region. The rate of mutation accumulation in the mouse p53 pseudogene was estimated to be 1.4-2.1x10(-8) mutations/bp/year, which is 20-30 times faster than that of the functional p53 and makes the dating possible for the time range of 10(6) years or more. From comparison of the mutation spectrum, the origin of laboratory mice was identified to one of two M. m. domesticus groups.