Molecular diagnosis refers to the application of molecular biology methods to detect changes in the structure or expression level of genetic material in patients to make a diagnosis. Molecular diagnosis is the main method for predictive diagnosis, which can be used for the diagnosis of individual genetic diseases and prenatal diagnosis. Molecular diagnosis mainly refers to the detection of genes encoding various structural proteins, enzymes, antigen antibodies, and immune active molecules related to diseases.

Reasonable specimen collection is crucial to ensure the integrity of the specimen and the accuracy of the qualitative/quantitative detection of nucleic acids. Specimens should be collected in strict accordance with appropriate biosafety guidelines. Improper specimen handling can lead to nucleic acid degradation and erroneous patient test results.

1. Specimen identification

When collecting specimens, the identity of patients and their specimens should be clarified, and patient privacy should be fully respected. At the same time, medical personnel should be provided with reasonable and sufficient information related to testing and treatment. Specimens should be securely labelled, including at least: identification number, date and time of collection, name of the person collecting the specimen, source of the specimen, etc.

2. Application form information

The application form should include at least the following information: identification number, admission registration number, patient name, date of birth, gender, ethnicity, date of collection, type of specimen, relevant clinical and laboratory information, name of doctor, department of specimen collection, test application reasons, etc.

3. Specimen Collection

Relevant safety precautions should be followed when collecting human tissue or body fluid specimens, and gloves should be worn to prevent the spread of blood-borne pathogens in the specimens and prevent the specimens from being contaminated by the exfoliated cells of the handlers. Certain testing methods may require additional precautions and collection instructions, such as HPV testing, cervical specimens should be collected before the acetic acid test. When using different testing methods, laboratories should consider potential sources of interference and contamination, and properly instruct and train clinicians to collect samples according to the specific method or testing system's sample collection requirements. After the clinical laboratory receives the specimen, the specimen information should be input into the Laboratory Information System (LIS) as soon as possible, and the received specimen should be processed as soon as possible. Rejection should be considered if specimens exhibit conditions such as hemolysis, frozen blood, or improper labeling.