| Abstract: | A captive herd of Speke' gazelle was screened for genetic variability at 28 enzyme-coding loci, the nuclear ribosomal DNA (rDNA), and the mitochondrial DNA (mtDNA). There is one variable restriction site out of 52 in the rDNA and three variable sites out of 41 in the mtDNA. This amount of mitochondrial diversity is low for a mammal, but is about the maximum to be expected given that the entire herd is derived from three females. However, 14% of the enzymecoding loci were polymorphic, a figure typical for mammals. Hence, despite the fact that the herd was founded by one male and three females, much genetic variation is still present. It is therefore important to continue breeding programs designed to maintain genetic diversity. MtDNA is maternally inherited, so tracing back from the current animals through females allowed us to infer that each founding female had a distinct mtDNA haplotype. Hence, the founding females could not have shared the same mother. The nuclear variability could also be traced back through the pedigrees to the founders. One female was found to have contributed none of the assayed genetic variability to the current herd. “Gene drop” simulations of the herd indicated that this was the only founder for which much genetic variability had already been lost because of breeding decisions made during the early history of the herd. This illustrates the importance of implementing breeding programs designed to preserve genetic variability as soon as possible. |
