Sanetra Matthias, Henning Frederico, Fukamachi Shoji, Meyer Axel
Department of Biology, Lehrstuhl fur Zoologie und Evolutionsbiologie, University of Konstanz, Konstanz, Germany.
Genetics. 2009 May;182(1):387-97. doi: 10.1534/genetics.108.089367. Epub 2008 Aug 30.
Cichlid fishes compose an astonishingly large number of species and formed species flocks in record-breaking time. To facilitate efficient genome scans and comparisons of cichlid genomes, we constructed a medium-density genetic linkage map of microsatellite markers of Astatotilapia burtoni. The mapping cross was derived from two inbred laboratory lines to obtain F(2) progeny by intercrossing. The map revealed 25 linkage groups spanning 1249.3 cM of the genome (size approximately 950 Mb) with an average marker spacing of 6.12 cM. The seven Hox clusters, ParaHox C1, and two paralogs of Pdgfrbeta were mapped to different linkage groups, thus supporting the hypothesis of a teleost-specific genome duplication. The A. burtoni linkage map was compared to the other two available maps for cichlids using shared markers that showed conservation and synteny among East African cichlid genomes. Interesting candidate genes for cichlid speciation were mapped using SNP markers.
丽鱼科鱼类构成了数量惊人的众多物种，并在破纪录的时间内形成了物种群。为了便于进行高效的基因组扫描和丽鱼科基因组比较，我们构建了伯氏非鲫微卫星标记的中密度遗传连锁图谱。作图杂交源自两个近交实验室品系，通过杂交获得F(2)后代。该图谱揭示了25个连锁群，覆盖基因组1249.3厘摩（基因组大小约950兆碱基对），平均标记间距为6.12厘摩。七个Hox基因簇、ParaHox C1以及血小板衍生生长因子受体β（Pdgfrbeta）的两个旁系同源基因被定位到不同的连锁群，从而支持了硬骨鱼特异性基因组复制的假说。利用共享标记将伯氏非鲫连锁图谱与另外两张现有的丽鱼科图谱进行比较后发现，东非丽鱼科基因组之间存在保守性和共线性。使用单核苷酸多态性（SNP）标记定位了丽鱼科物种形成的有趣候选基因。
