High-resolution GTG-banded chromosomes of cattle, sheep, and goat: a comparative study.

We compared in detail the GTG-banding patterns of the chromosomes of cattle, sheep, and goat. Minor differences were revealed between the patterns of cattle on the one hand, and sheep/goat chromosomes on the other. These differences concerned mainly the pericentromeric regions of autosomes. Based on comparative data, we suggest how the contemporary cattle X chromosome might have arisen from the ancestral goat type as a result of rearrangements. No differences were found between the G-banded chromosomes of goat and sheep. Also, ideograms of the prometaphase GTG-banded chromosomes of cattle are given with descriptions of the chromosomes thought previously to be difficult to identify.