求教什么是stop-gain突变呀？

无义突变=Non-sense mutation
其实在我看来几乎跟stop-gain是一个意思了。
不过有人将Non-sense mutation非常详细划分4种情况。你参考

stop-gain: a mutation that results in a premature termination codon (a stop was gained), which signals the end of translation. This interruption causes the protein to be abnormally shortened. The number of amino acids lost mediates the impact on the protein’s functionality and whether it will function whatsoever.

stop-loss: a mutation in the original termination codon (a stop was lost), resulting in abnormal extension of a protein’s carboxyl terminus.

start-gain: creates a ATG start codon upstream of the original start site. If the new ATG is near the original start site, in-frame within the processed transcript and downstream to a ribosomal binding site, it can be used to initiate translation. The likely effect is additional amino acids added to the amino terminus of the original protein. Frame-shift mutations are also possible in start-gain mutations, but typically do not affect translation of the original protein.

start-loss: a point mutation in a transcript’s ATG start codon, resulting in the reduction or elimination of protein production.

原文 求教什么是stop-gain突变呀？ - 分子生物 - 生物信息 - 小木虫论坛-学术科研互动平台 (muchong.com)