Molecular diagnosis is a technology that uses molecular biology to detect specific changes in the structure or expression level of some genetic material in the patient’s body. This technology can make a diagnosis for the patient in time and is a way to predict the diagnosis. It can not only diagnose individual genetic diseases, but also complete prenatal diagnosis.
Specimen collection method for molecular diagnosis
Reasonable collection of specimens can make the specimens more complete, and at the same time can make the detection more stable and accurate. Specimens need to be collected according to more appropriate biological guidelines. Some unsuitable specimens are likely to cause nucleic acid degradation, and the accuracy of patient test results cannot be guaranteed.
(1) Specimen identification
In the process of specimen collection, the inspector must clarify the identity of the patient and the specific specimen, respect the personal privacy of the patient, learn more about the test and treatment related information, and stick the specimen-related labels on the specimen. The content includes the time of collection and the name of the collector.
(2) Application form information
The application form must include at least the following information, such as the type of specimen, the name of the doctor, and the name of the patient.
(3) Specimen collection
In the process of collecting human tissue or human body fluid specimens, the relevant safety precautions should be fully observed. For example, the collector must wear gloves to avoid the spread of blood-borne pathogens in the specimens, and at the same time, try to prevent the specimens from being processed. Cell infection revealed by personnel. Some more specific detection methods may require additional precautions and collection instructions. However, laboratories need to use different detection methods, and at the same time, they must also consider the potential interference and pollution sources of these detection methods. After receiving the specimen, the clinical laboratory must enter the specimen information into the new system as soon as possible. At the same time, it must also process the specimen as soon as possible. Once the specimen has improper conditions such as hemolysis, it should be considered for rejection. .
(4) Anticoagulant
The collection of blood and bone marrow puncture specimens needs to use reasonable anticoagulation tubes or test tubes containing other additives as far as possible. When choosing test tube additives, it should be determined according to the specific type of analyte, the experiment of the analyte, and the amount of specimen. Heme is likely to inhibit the response of some of these factors. It is recommended to use anticoagulants to detect plasma or bone marrow aspiration specimens. If it is measured as some specific substances in the cells, when the tester collects blood or bone marrow, his equipment should include a stabilizer, and a stabilized solution should be added immediately after the collection.
The basic process of molecular diagnosis
The first is the collection and preparation of samples. Extract some genes for detection from the sample, and then amplify them. Once the genetic material is isolated, the genetic material must be immediately amplified to a detectable quantity, so that relevant diagnostic commands can be made. Afterwards, detection is performed. After enough target substances are obtained, the optical fiber sensor can read the signals related to the specific target substances that are about to be detected. The signal can be single or multiple, which can realize the detection of multiple different target substances in one reaction. Finally, there is data analysis, that is, a comprehensive analysis of the signals read out in the detection step, and converting the analysis results into understandable information, so as to provide clinicians with more detailed diagnosis results.
Most of the core technologies of molecular diagnostic laboratories are related to detection specificity and relatively short DNA or RNA fragments. This technology can fully diagnose infectious diseases, and can effectively identify and compare drugs that may affect drug metabolism. Special gene variants, or detection of disease-related genes and cancer-related genes. Molecular diagnostic laboratories must use well-defined workflows to obtain more stable and effective results.
