Extreme genetic differences among populations of Gazella granti, Grant's gazelle, in Kenya

Mitochondrial DNA (mtDNA) control region sequences from six Kenyan Grant's gazelle (Gazella granti) populations were highly divergent among locations. Neighbouring populations not separated by geographical or vegetational barriers exhibited a nucleotide sequence divergence of about 14 per cent. A similar level of divergence. separates Grant's gazelles from a closely related species, the Soemmering's gazelle (G. soemmeringii). Nuclear microsatellite repeat number variation at two loci also indicated substantial population genetic differentiation. Despite high levels of sequence divergence, populations of Grant's gazelles were more closely related to each other than to Soemmering's and Thomson's gazelles (G. thomsoni) as measured by nucleotide sequence divergence at the mtDNA protein coding cytochrome b gene and the nuclear cc-lactalbumin gene. This pattern of extensive differentiation is hypothesized to have resulted from recently established contacts between formerly allopatric populations.