已知在含有与电泳方向平行的DNA变性剂梯度的聚丙烯酰胺凝胶上电泳时,有着单一碱基置换的异源双链核酸分子的解链特性与野生型的同源双链汾子含有更大的差别,故可用以分离检出此类突变型。作者选择4种不同的具有已知单一碱基置换的β-地中海贫血症的等位基因进行研究,其突变位置是人体β-珠蛋白基因中的第一个间隔序列(IVS-1)中的第1、5、6和110碱基处(分别记为IVS1,1IVS1,5、IVS1,6和IVS1,110)。表现为RNA拼接缺陷。 It is known that the melting behavior of a heteroduplexed nucleic acid molecule with a single base substitution when electrophoresed on a polyacrylamide gel containing a gradient of DNA denaturant parallel to the direction of electrophoresis is similar to that of a wild-type homoduplex More difference, it can be used to isolate such mutations detected. The authors selected four different alleles of β-thalassemia with known single base substitutions at the site of mutation in the first spacer sequence (IVS-1) in the human β-globin gene 1, 5, 6 and 110 bases (denoted as IVS1, 1IVS1,5, IVS1,6 and IVS1,110, respectively). The performance of RNA splicing defects.