The chromosomal distribution of the major and minor satellite is not conserved in the genusMus

Abstract

The cytological distribution of the major and minor satellite first identified in Mus musculus was studied in the karyotypes of three related subspecies and two other species of the genus Mus. Both the major and minor satellite showed species dependent hybridization patterns. The major satellite is confined to the centromere region in M. musculus and related subspecies. However, in M spretus and M. caroli, the chromosomal arm regions contain this sequence class. In contrast the minor satellite is found at the kinetochore region in M. musculus and related subspecies but is distributed throughout the entire centromeric domain in M. spretus and appears to be excluded from the chromosomes of M. caroli. There is an apparent correlation between the chromosomal location of these satellites and their phylogenetic relationship. Determination of the biological roles of the major and minor satellites from M. musculus must take into account their differential chromosomal distribution in other Mus species.