Abstract
The seven metacentric chromosomes of the tobacco mouse, Mus poschiavinus, have been isolated in seven homozygous lines on a predominantly Mus musculus genetic background. Meiotic analyses of males doubly heterozygous for each metacentric and translocations marking at least one linkage group (LG) have enabled nine of the fourteen LG’s carried by the metacentrics to be identified. T1Bnr carries LG XIII (chromosome 1), T2Bnr carries LG’s VIII and XI (chromosomes 4 and 6), T3Bnr carries LG XVII and an unknown LG common to T6Ca and T1Ald (chromosomes 5 and 15), T4Bnr carries LG XIV (chromosome 13), T5Bnr carries LG XVIII (chromosome 8), T6Bnr carries LG’s II and III (chromosomes 9 and 14), and T7Bnr carries LG IX (chromosome 17). No other LG known to be marked by a translocation is involved.