| abstract |
A method for detecting nonsense mutations andnframeshift mutations which is simple and which may benapplied even when the size of the test DNA is large isndisclosed. In the method of the present invention, antest nucleic acid fragment is inserted into a site of anvector having a promoter, a translational initiationncodon downstream of the promoter, a reporter gene whichnis a structural gene located downstream of thentranslational initiation codon, which is operably linkednto the promoter and which encodes a polypeptide. Anfusion polypeptide formed by ligating the N-terminal ofnthe polypeptide to another polypeptide is detectablenbased on a function of the polypeptide encoded by thenreporter gene. The site into which the test nucleic acidnfragment is inserted is located downstream of thentranslational initiation codon and upstream of thenreporter gene, and the test nucleic acid fragment is onenwhich allows, when inserted, in-frame location of thenreporter gene with respect to the translationalninitiation codon when the test nucleic acid fragment isnnormal type. The test nucleic acid fragment and thenreporter gene downstream thereof in the resultingnrecombinant vector are then expressed in a host cell, andnwhether or not the fusion polypeptide having the functionnof the polypeptide encoded by the reporter gene isnproduced is determined. |