内含子最初是存在于原始基因,随后从绝大多数的现存原核生物中丢失,还是后来再加至真核生物基因中,这是现代生物学中争论最大的问题。所有内含子都以同一方式来自一个共同祖先的观点也未必正确。有作者认为,Ⅰ类内含子通过插入基因来完成自身繁殖,实际上,内含子的发育是由一个非常有效的机制完成的。这也提示了Ⅱ类内含子插入的证据以及这些内含子与自主成份之间的关系。 Introns were initially present in the original gene, then lost from the vast majority of existing prokaryotes, or later added to eukaryotic genes, the most debated issue in modern biology. It may not be true that all introns come from a common ancestor in the same way. According to the author, class I introns accomplish their own breeding by inserting genes. In fact, intron development is accomplished by a very effective mechanism. This also suggests evidence of insertion of class II introns and the relationship between these introns and autonomic components.