[Heterochromatin and euchromatin regions in the chromosomes of various representatives of the subfamily Bovinae].

Heterochromatin distribution was studied in three species of subfamily Bovinae: bison (Bison bison), European bison (Bison bonasus), and gayal (Bos frontalis). In all of the studied species, C- and CMA3-banding and in situ hybridization with satellite DNAII (satDNAII) revealed the conservative distribution of heterochromatic regions in autosomes; sex chromosomes did not contain the classical constitutive heterochromatin. The Y chromosome was the most variable element of the karyotypes of both bison species and the gayal. A mechanism for formation of the acrocentric Y chromosome in B. bison was suggested. This hypothetical mechanism included breakage of the p arm at the telomeric region and subsequent translocation and inversion. The map of B. bison chromosomes (491 bands per haploid set) is presented. The data obtained are discussed in terms of speciation and the evolution of Bovinae karyotypes.