QTL定位中常见的12个问题

表型正态分布不是该性状是否适合QTL作图的必要条件，但一般要求表型数据的随机误差服从正态分布。高密度分子标记为分离紧密连锁QTL提供了可能，但高密度标记必须辅以大作图群体，才能提高QTL作图的准确度。缺失标记对QTL作图的影响等同于一个缩小了的作图群体。奇异分离标记对作图的影响可以用与其连锁的QTL遗传方差的变化来衡量，有时奇异分离标记会增大QTL的方差进而提高检测功效，这种影响会随着连锁距离的增大而减弱。缺失标记和奇异分离对QTL位置和效应估计的影响不大，对于效应较大的QTL和较大的群体，缺失标记和奇异分离对QTL作图的影响可以忽略。

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