Thylogale spp.(pademelons) retain the plesiomorphic (ancestral) 2n= 22 karyotype for the
marsupial family Macropodidae (kangaroos and wallabies). The swamp wallaby, Wallabia
bicolor, has the most derived macropodid karyotype with the lowest chromosome number
(2n= 10 female, 11 male), and a multiple sex chromosome system (XX female, XY1Y2 male).
All but one of the W. bicolor chromosomes are fusion chromosomes. Two of these
chromosomes, the X chromosome and chromosome 1, are composed of three …

In marsupial karyotypes with little heterochromatin, the telomeric sequence (T 2 AG 3) n, is
involved in chromosome rearrangements. Here we compare the distribution of the (T 2 AG 3)
n sequence in chromosomes recently derived by fusions and other rearrangements (7–0.5
MYBP) with its distribution in chromosomes derived earlier (24–9 MYBP). We have
previously shown that the (T 2 AG 3) n sequence is consistently retained during
chromosome rearrangements that are recent (7–0.5 MYBP). We suggest that in less recent …