The genetic improvement of the water buffalo (Bubalus bubalis): the contribution of the cytogenetics

Although water buffalo is only 1/9 of the cattle population, it interests a larger human population, especially in southeastern countries. The DNA-sequence of the entire genome has been performed for several domestic species but it is still lacking in river buffalo. However, high resolution Q-, G-, and R-banded standard karyotypes are available and cytogenetic maps at the low resolution density have been constructed for river buffalo. In addition, cytogenetic analyses on females with reproductive problems have established that about 20% of these animals are sterile for serious damages to internal sex adducts due to the presence of sex chromosome abnormalities. In this study I summarize the contribution of the cytogenetics in the genetic improvement of the water buffaloes concerning the following aspects: (a) chromosome characterization by high resolution chromosome banding; (b) chromosome evolution within Bovidae family by using both comparative chromosome banding and gene order (FISH-mapping technique) approaches; (c) clinical cytogenetics applied to reproduction; (d) molecular ytogenetics (the most advanced cytogenetic maps).