Rare diseases usually refer to diseases with extremely low incidence rates. There are more than 7,000 known rare diseases in the world. Due to the scarcity of cases and complex clinical manifestations, the diagnosis of rare diseases has long been a major problem in the medical field. In recent years, the molecular diagnosis platform has been widely used in the diagnosis of rare diseases with its advantages of high sensitivity and high specificity, bringing new hope to patients with rare diseases.
In terms of application status, the various technologies of the molecular diagnosis platform have played a key role in the diagnosis of rare diseases. Gene sequencing technologies, such as whole exome sequencing (WES) and whole genome sequencing (WGS), can comprehensively test the genes of patients. About 80% of rare diseases are caused by genetic factors. Through gene sequencing, potential pathogenic gene mutations can be found. For example, in the diagnosis of hereditary peripheral neuropathy, genetic testing technology helps doctors accurately determine the type of disease. my country's testing level in this regard has reached international advanced levels, and some areas such as peripheral nerve pathology examination are even in a leading position. However, even with advanced whole exome testing, the average detection rate of clinical patients is only around 35%, which shows that current technology still has limitations.
In addition to gene sequencing, PCR technology in the molecular diagnosis platform is also commonly used for the diagnosis of rare diseases. For some rare diseases with known pathogenic genes and relatively fixed mutation types, PCR technology can quickly and accurately detect specific gene fragments and provide a basis for diagnosis. However, this technology is limited to the detection of known mutations, and it is difficult to give a comprehensive diagnosis for rare diseases with unknown mutations or complex gene structure changes.
From the actual results, the molecular diagnosis platform has indeed significantly improved the diagnostic efficiency and accuracy of rare diseases. In the past, patients with rare diseases often went through a long process of seeking medical treatment, with an average diagnosis time of 5 to 7 years. Today, with the help of the molecular diagnosis platform, some patients can identify the cause of the disease in a relatively short period of time, buying precious time for subsequent treatment. For example, in some tertiary hospitals, through a complete molecular diagnosis process, the diagnosis time of some rare disease patients has been shortened to several months. However, there is a large gap in the molecular diagnosis level between different regions and hospitals at all levels. Some grassroots hospitals even lack basic molecular diagnostic equipment and professional talents, resulting in misdiagnosis and missed diagnosis of rare diseases.
At present, the molecular diagnosis platform still faces many challenges in the application of rare disease diagnosis. On the one hand, the cost of testing is high. Although the cost of sequencing has decreased with the development of technology, for many families, the cost of whole exome testing or whole genome testing is still high, which limits the popularity of testing. On the other hand, the interpretation of test results is complicated. There are many types of rare disease gene mutations, and the pathogenicity of some mutations is still unclear. A professional medical genetics team is required for comprehensive analysis. However, such professionals are relatively scarce in China.
The molecular diagnosis platform has broad prospects in the field of rare disease diagnosis. On the technical level, with the continuous innovation of sequencing technology, such as the gradual maturity and popularization of third-generation sequencing technology, it is expected to achieve faster, more accurate and lower-cost genetic testing, further improving the diagnosis rate of rare diseases. At the same time, the integration of multi-omics technologies, such as combining genomics with transcriptomics and metabolomics, can analyze disease mechanisms from multiple levels and provide more comprehensive information for rare disease diagnosis. In terms of clinical application, as the country pays more and more attention to the diagnosis and treatment of rare diseases, more and more hospitals will establish complete molecular diagnostic laboratories, strengthen talent training, improve the diagnosis awareness and capabilities of primary medical institutions for rare diseases, and promote the widespread application of molecular diagnosis platforms in the diagnosis of rare diseases, so that more rare disease patients can benefit.
