The Barcelona Robertsonian system (BRbS) presents mice with standard karyotype (diploid number 40) but also carrying Robertsonian fusions (ehich lead to variable diploid numbers ranging from 28 to 39)
aRatio of expected to observed breakpoints.bFive inversion events occur at telomeres, so each makes only one breakpoint.c21 breakpoints are shared by a reciprocal translocation and an inversion.
