染色体重组与连锁互换是遗传学教学的重点和难点。为使学生更好地理解此方面知识, 我们课题组前期利用图位克隆(map-based cloning)技术, 克隆了1个调控水稻(Oryza sativa)类病变表型的基因SPL5, 并基于此设计了一个新的综合型遗传学实验, 即利用DNA分子标记对基因进行定位。实验中学生利用水稻spl5突变体与野生型杂交获得的F₂代定位群体和多态性分子标记, 对spl5突变进行染色体连锁分析、初步定位和遗传作图。该教学实验不仅可有效促进学生对遗传学三大定律的理解, 而且对其开阔视野、提高解决问题和团队协作的能力也有促进作用。

Recombination, linkage and crossover of chromosomes are the key and difficult points in genetics teaching. For students’ comprehensively understanding these concepts in teaching, we designed a new genetic experiment named ‘Gene mapping using DNA molecular markers’ based on the principle of the map-based cloning method, using our previous studies on cloning of a rice lesion-mimic phenotype regulating gene SPOTTED LEAF 5 (SPL5) as an example. In this experiment, students are instructed to perform the linkage analysis, genetically map the spl5 mutation and align a genetic map by using an F₂ population generated by a cross between spl5 and wild-type plants and polymorphic molecu- lar markers. This teaching experiment can not only effectively promote students' understanding of the three Laws of genetics, but also be helpful to broaden their vision and improve their ability to solve problems and work in a team.