O'Malley K G, Sakamoto T, Danzmann R G, Ferguson M M
Department of Zoology, University of Guelph, Guelph, Ontario, Canada N1G 2W1.
J Hered. 2003 Jul-Aug;94(4):273-84. doi: 10.1093/jhered/esg067.
We incorporated 69 microsatellite loci into an existing data set of 132 markers to test for quantitative trait loci (QTLs) affecting spawning date and body weight in a backcross between two outbred strains of rainbow trout (Oncorhynchus mykiss). Twenty-six linkage groups were identified and synteny of duplicated microsatellite markers was used to confirm 13 homeologous chromosome pairs. Gene-centromere data were used to localize the centromeres for 13 linkage groups whose orientations were previously unknown. We applied a combination of interval mapping and single marker analysis to the segregating maternal and paternal alleles at 201 microsatellite loci. Four spawning date QTLs with suggestive evidence for an additional two QTLs were detected in female trout spawning at 3 and 4 years of age. Similarly we detected three QTLs for body weight in females at 2 years of age plus four suggestive QTLs for this trait. We found marginal evidence that three pairs of ancestral homeologues contained detectable QTLs for the same trait. In one of the three pairs of homeologues, the duplicated QTL regions mapped to the same relative chromosomal location, while the exact localization of the QTL position in one of the other pairs was difficult to infer since it was based on data from a male-derived map. The existing data were unable to refute a hypothesis that duplicated functional genes will be maintained within the telomeric regions of salmonids due to preferential male-mediated crossing over in this region. Two of the four spawning date QTLs were detected on linkage groups with unknown homeologous relationships. QTLs with possible pleiotropic effects on both spawning date and body size were localized to two linkage groups.
我们将69个微卫星基因座纳入现有的132个标记数据集，以检测影响虹鳟（Oncorhynchus mykiss）两个远交品系回交后代产卵日期和体重的数量性状基因座（QTL）。鉴定出26个连锁群，并利用重复微卫星标记的同线性来确认13对同源染色体。利用基因 - 着丝粒数据定位了13个连锁群的着丝粒，这些连锁群的方向此前未知。我们对201个微卫星基因座上分离的母本和父本等位基因应用了区间作图和单标记分析相结合的方法。在3岁和4岁产卵的雌性虹鳟中检测到4个产卵日期QTL，另有2个QTL有暗示性证据。同样，我们在2岁雌性虹鳟中检测到3个体重QTL以及该性状的4个暗示性QTL。我们发现有少量证据表明，三对祖先同源染色体包含相同性状的可检测QTL。在三对同源染色体中的一对中，重复的QTL区域映射到相同的相对染色体位置，而另一对中QTL位置的确切定位难以推断，因为它基于来自雄性衍生图谱的数据。现有数据无法反驳这样一个假设：由于该区域优先发生雄性介导的交换，重复的功能基因将保留在鲑科鱼类的端粒区域内。在同源关系未知的连锁群上检测到四个产卵日期QTL中的两个。对产卵日期和体型可能具有多效性影响的QTL定位到两个连锁群上。
