Leamy Larry J, Routman Eric J, Cheverud James M
Department of Biology, University of North Carolina at Charlotte, Charlotte, North Carolina, 28223.
Department of Biology, San Francisco State University, San Francisco, California, 94132.
Evolution. 1997 Jun;51(3):957-969. doi: 10.1111/j.1558-5646.1997.tb03676.x.
An interval mapping procedure was used to search for and describe the effects of any quantitative trait loci (QTLs) for directional asymmetry (DA) and fluctuating asymmetry (FA) of 10 bilateral mandible characters in house mice. It was hypothesized that more QTLs would be found for DA than for FA, but that any discovered for FA should tend to exhibit dominance. All mandible characters were triply measured and 76 microsatellite markers were scored in an average of 471 mice from the F intercross of the Large (LG/J) and Small (SM/J) inbred strains. A total of 16 QTLs significantly affected DA in nine of the 10 mandible characters, and this was more than the 9.5 expected by chance alone. These QTLs were found on seven of the 19 chromosomes, often at or near locations of QTLs affecting the mean of the two sides for various dimensions on the mandible. It was concluded that there is genetical variability for DA in these characters, although its level was low (4.4% of the total variation in this particular F population). Eleven QTLs were detected for FA, suggesting that there is very little genetic variability for FA, at least as seen in the mandible characters in this particular F population. As hypothesized, however, these QTLs did tend to exhibit dominance.
采用区间定位程序来搜索并描述家鼠10个双侧下颌骨性状的定向不对称（DA）和波动不对称（FA）的任何数量性状基因座（QTL）的效应。研究假设是，与FA相比，会发现更多影响DA的QTL，但任何影响FA的QTL应倾向于表现出显性。对所有下颌骨性状进行了三次测量，并对来自大（LG/J）和小（SM/J）近交系F代杂交的平均471只小鼠的76个微卫星标记进行了评分。共有16个QTL显著影响10个下颌骨性状中的9个的DA，这比仅由随机因素预期的9.5个更多。这些QTL在19条染色体中的7条上被发现，通常位于影响下颌骨各维度两侧平均值的QTL的位置或附近。得出的结论是，这些性状中DA存在遗传变异性，尽管其水平较低（在这个特定的F群体中占总变异的4.4%）。检测到11个影响FA的QTL，这表明FA的遗传变异性非常小，至少在这个特定的F群体的下颌骨性状中是这样。然而，正如所假设的那样，这些QTL确实倾向于表现出显性。
