Houlden B A, England P R, Taylor A C, Greville W D, Sherwin W B
School of Biological Science, University of NSW, Australia,
Mol Ecol. 1996 Apr;5(2):269-81.
Genotyping of koalas at CA-repeat microsatellite loci has revealed significant differences in the levels of allelic diversity (A) and expected heterozygosity (H(E)) between populations from north-eastern and south-eastern Australia. In the 10 populations studied, allelic diversity ranged from 8.0 in the Nowendoc population to 1.7 in the Kangaroo Is. population, and values of H(E) ranged from 0.831 in the Nowendoc population to 0.331 in the Kangaroo Is. population. Data from pooled populations revealed koalas from the north-eastern region had significantly higher levels of allelic diversity (A = 11.5 +/- 1.4) than those from south-eastern Australia (A = 5.3 +/- 1.0). Furthermore significantly higher heterozygosity levels were found in the north-eastern (H(E) = 0.851) vs. the south-eastern (H(E) = 0.436) regions of Australia. Following a near-extinction bottleneck in the 1920s, mainland Victorian and Kangaroo Is. koalas have been involved in an extensive program of relocations. The source populations of the relocated animals were islands in Westernport Bay, which were founded by very few individuals in the late 1800s and early 1900s. The significantly lower levels of variation between south-eastern Australian populations suggests that human intervention has had a severe effect on levels of genetic diversity in this region, and this may have long-term genetic consequences.
对考拉CA重复微卫星位点进行基因分型后发现，澳大利亚东北部和东南部种群之间的等位基因多样性（A）水平和预期杂合度（H(E)）存在显著差异。在所研究的10个种群中，等位基因多样性范围从诺温多克种群的8.0到袋鼠岛种群的1.7，H(E)值范围从诺温多克种群的0.831到袋鼠岛种群的0.331。合并种群的数据显示，来自东北部地区的考拉等位基因多样性水平（A = 11.5 +/- 1.4）显著高于澳大利亚东南部的考拉（A = 5.3 +/- 1.0）。此外，在澳大利亚东北部（H(E) = 0.851）与东南部（H(E) = 0.436）地区发现了显著更高的杂合度水平。在20世纪20年代经历了近乎灭绝的瓶颈期后，维多利亚州大陆和袋鼠岛的考拉参与了一项广泛的重新安置计划。重新安置动物的来源种群是西港湾的岛屿，这些岛屿在19世纪末和20世纪初由极少数个体建立。澳大利亚东南部种群之间显著较低的变异水平表明，人类干预对该地区的遗传多样性水平产生了严重影响，这可能会产生长期的遗传后果。
