Method for identifying polymorphism of nucleic acid molecules

A method for identifying a polymorphism of nucleic acid molecules comprising:

• (a) preparing a sample solution comprising a first nucleic acid probe, which is labeled with a fluorescent substance and specifically hybridizes with a single-stranded nucleic acid molecule comprising a first type of base sequence in a polymorphic sequence, and a target nucleic acid molecule;
• (b) hybridizing nucleic acid molecules in the sample solution prepared in (a);
• (c) calculating the number of molecules of hybrids comprising the first nucleic acid probe in the sample solution prepared in (a) after carrying out (b) that comprises:
• using the optics of a confocal microscope or multiphoton microscope to move the location of a photodetection region of the optics in the sample solution,
• moving the location of the photodetection region of the optics in the sample solution while detecting fluorescence emitted from the hybrids in the photodetection region,
• individually detecting hybrids by individually detecting optical signals from each hybrid among the detected light, and
• counting the number of the target nucleic acid molecule detected during movement of the location of the photodetection region by counting the number of individually detected hybrids;
• (d) preparing a sample solution comprising a second nucleic acid probe, which is labeled with a fluorescent substance and in which the base sequence thereof differs from the base sequence of the first nucleic acid probe, and the target nucleic acid molecule;
• (e) hybridizing the nucleic acid molecules in the sample solution prepared in (d);
• (f) calculating the number of molecules of hybrids comprising the second nucleic acid probe in the sample solution prepared in (d) after carrying out (e) that comprises:
• using the optics of a confocal microscope or multiphoton microscope to move the location of a photodetection region of the optics in the sample solution,
• moving the location of the photodetection region of the optics in the sample solution while detecting fluorescence emitted from the hybrids in the photodetection region,
• individually detecting hybrids by individually detecting optical signals from each hybrid among the detected light, and
• counting the number of the target nucleic acid molecule detected during movement of the location of the photodetection region by counting the number of individually detected hybrids;
• and,
• (g) identifying a polymorphism of the target nucleic acid molecule based on the results of (c) and (f).