At present, PCR methods are often used in domestic genetic diagnosis, involving PCR machines. The price of this instrument varies between domestic and imported products. You can buy it as cheap as 20,000 to 30,000 yuan, and as expensive as more than 200,000 yuan. Laboratories and national institutions with better conditions have also tried the fluorescence quantitative PCR method. This method has high technical content and requires the use of a fluorescence quantitative PCR instrument, and the price ranges from 200,000 to 700,000.
Products using loop-mediated isothermal amplification technology do not require special instruments for clinical diagnosis. However, the development process of finished kits for clinical use involves the selection of primers and the adjustment of primer concentrations. As well as the optimization of reaction temperature and time, a quantitative method is needed to help researchers analyze and select data. Therefore, we recommend the use of Rongyan's patented product LA-320C or LA-500 real-time turbidity meter.
The loop-mediated isothermal amplification method, whose English name is loop-mediated isothermal amplification, is a new type of nucleic acid amplification method. It is characterized by designing 4 specific primers for 6 regions of the target gene. Under the action of strand displacement DNA polymerase (Bst DNA polymerase), constant temperature amplification at 60--65°C can achieve 10^9 to 10^10-fold nucleic acid amplification in about 15-60 minutes, which is simple to operate and specific. It has the characteristics of strong resistance and easy product detection. During DNA synthesis, the pyrophosphate ions precipitated from the deoxyribonucleic acid triphosphate substrate (dNTPs) react with the magnesium ions in the reaction solution to produce a large amount of magnesium pyrophosphate precipitate, which appears white. Therefore, turbidity can be used as an indicator of reaction, and the amplification can be identified by simply observing the white turbid precipitate with the naked eye, without the need for cumbersome electrophoresis and ultraviolet observation. Since the loop-mediated isothermal amplification reaction does not require a PCR machine and expensive reagents, it has broad application prospects.