Patent ID: 7790368

Claim:
A method for analyzing a nucleic acid comprising steps of extracting, amplifying, and detecting the nucleic acid of interest, wherein said method comprises the steps of: obtaining a sample; adding an internal control for extraction to the sample; extracting the nucleic acid; adding an internal control for amplification to the sample subsequent to the step of extracting, wherein the internal control for amplification is different from the internal control for extraction and an internal control for detection; amplifying the nucleic acid; adding the internal control for detection to the sample subsequent to the step of amplifying, wherein the internal control for detection is different from the internal control for extraction and the internal control for amplification; detecting the nucleic acid in the sample; judging the success or failure of each of the steps of extracting, amplifying, and detecting from detection results obtained for each of said internal controls, and wherein the step of judging the success or failure of the steps of extracting, amplifying and detecting includes the step of judging whether detection results for each of the internal controls is abnormal or undetected, or normal; and re-performing the above-mentioned steps from any of the steps which are judged as insufficient, such that analysis is re-performed from any one of the steps which are judged as insufficient based on the judgments of the success or failure of said nucleic acid extraction step, amplification step and detection step; and wherein the success or failure of said steps is judged from peak broadness together with peak intensity and shift in retention time of said respective internal control nucleic acids.