Huang Y, Liu Q, Tang B, Lin L, Liu W, Zhang L, Li N, Hu X
State Key Laboratory for Agrobiotechnology, China Agricultural University, Beijing, People's Republic of China.
Cytogenet Genome Res. 2008;121(2):130-6. doi: 10.1159/000125838. Epub 2008 Jun 9.
Molecular genetic maps can provide information for the identification and localization of major genes associated with quantitative traits. However, there are currently no published genetic linkage maps for any ratites. Herein, a preliminary genetic map of ostrich was developed using a two-generation ostrich reference family by linkage analysis of 104 polymorphic microsatellite markers, including 40 novel markers reported in this study. A total of 35 microsatellite markers were placed into 13 linkage groups. Five linkage groups are composed of three or more loci, whereas the remaining eight groups each contained two markers. The sex-averaged map spans 365.4 cM. The marker interval of each linkage group ranges from 5.3 to 25.4 cM, and the average interval distance is 16.61 cM. The male map covers 342.7 cM, with an average intermarker distance of 15.58 cM, whereas the female map is 456.7 cM, with the average intermarker spacing of 20.76 cM. In order to screen the orthologous loci between ostrich and chicken, all of the flanking sequences of the 104 polymorphic loci, nine monomorphic loci and a further 12 reported microsatellite loci for ostrich were screened against the chicken genomic sequence using the BLAST algorithm (Altschul et al., 1990), and corresponding orthologs were found for 13 sequences. The microsatellite loci and genetic map developed in this study will be useful for QTL mapping, population genetics and phylogenetic studies in the ratite. In addition, the 13 orthologous loci identified in this study will be advantageous to the construction of a comparative genetic map between chicken and ostrich.
分子遗传图谱可为与数量性状相关的主基因的鉴定和定位提供信息。然而，目前还没有已发表的任何平胸鸟类的遗传连锁图谱。在此，利用一个两代鸵鸟参考家系，通过对104个多态微卫星标记（包括本研究报道的40个新标记）进行连锁分析，构建了鸵鸟的初步遗传图谱。共有35个微卫星标记被定位到13个连锁群中。五个连锁群由三个或更多位点组成，而其余八个连锁群每个包含两个标记。两性平均图谱跨度为365.4厘摩。每个连锁群的标记间隔范围为5.3至25.4厘摩，平均间隔距离为16.61厘摩。雄性图谱覆盖342.7厘摩，标记间平均距离为15.58厘摩，而雌性图谱为456.7厘摩，标记间平均间距为20.76厘摩。为了筛选鸵鸟和鸡之间的直系同源位点，使用BLAST算法（Altschul等人，1990）将104个多态位点、9个单态位点以及另外12个已报道的鸵鸟微卫星位点的所有侧翼序列与鸡的基因组序列进行比对，发现13个序列有相应的直系同源序列。本研究中开发的微卫星位点和遗传图谱将有助于平胸鸟类的数量性状基因座定位、群体遗传学和系统发育研究。此外，本研究中鉴定出的13个直系同源位点将有利于构建鸡和鸵鸟之间的比较遗传图谱。
