Biology and Medicine

Overview of Various Molecular Diagnostic Methods

Jinying Lin^* Department of Immunology, the People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, People's Republic of China
^*Correspondence: Jinying Lin, Department of Immunology, the People’s Hospital of Guangxi Zhuang Autonomous Region, Nanning, People's Republic of China, Email:

Received: 22-Feb-2023, Manuscript No. BLM-23-20940; Editor assigned: 27-Feb-2023, Pre QC No. BLM-23-20940(PQ); Reviewed: 14-Mar-2023, QC No. BLM-23-20940; Revised: 21-Mar-2023, Manuscript No. BLM-23-20940(R); Published: 28-Mar-2023, DOI: 10.35248/0974-8369.23.15.554

Description

Disease diagnosis is an important step in modern medicine, and various methods have been developed over time to detect and identify the underlying causes of illnesses. In recent years, molecular methods have gained increasing prominence in disease diagnosis due to their high sensitivity, specificity, and speed. Molecular methods use the genetic material of pathogens or host organisms to detect, identify, and quantify diseases. The molecular methods of disease diagnosis includes Polymerase Chain Reaction (PCR), Nucleic Acid Amplification Tests (NAATs), and Next-Generation Sequencing (NGS).

PCR is a widely used molecular method that amplifies a specific segment of DNA or RNA in a sample to detect and identify pathogens. The technique relies on the ability of Taq polymerase to extend primers, which are short DNA sequences that bind to the target DNA or RNA. The primers flank the target sequence and define the region to be amplified. The PCR process involves three steps: Denaturation, annealing, and extension. Denaturation involves heating the DNA or RNA sample to separate the double-stranded DNA or RNA into single strands. Annealing involves cooling the sample to allow the primers to bind to the complementary target sequence. Extension involves raising the temperature again to allow Taq polymerase to extend the primers, resulting in the amplification of the target sequence. The amplified sequence can be detected by gel electrophoresis or other detection methods.

NAATs are a group of molecular methods that use various amplification techniques to amplify nucleic acids from pathogens or host organisms. NAATs include PCR, Reverse Transcription PCR (RT-PCR), Loop-Mediated Isothermal Amplification (LAMP), and Strand Displacement Amplification (SDA). NAATs are highly sensitive and specific and can detect a wide range of pathogens, including viruses, bacteria, fungi, and parasites. These have several advantages over conventional methods, including faster turnaround times, lower detection limits, and the ability to detect multiple pathogens simultaneously. NGS is a powerful molecular method that can sequence millions of DNA or RNA fragments in parallel to detect and identify pathogens. NGS involves several steps, including library preparation, sequencing, and data analysis. Library preparation involves fragmenting the DNA or RNA sample and attaching sequencing adapters to the fragments. The fragments are then amplified by PCR to produce a sequence of DNA or RNA fragments. Sequencing involves using a sequencer to read the nucleotides in the fragments, generating millions of short reads. Data analysis involves aligning the short reads to a reference genome or assembling them into contigs to identify the pathogen. NGS can detect and identify pathogens with high accuracy and speed, making it a valuable tool in disease diagnosis.

Molecular methods are highly specific, enabling the detection and identification of pathogens with a high degree of accuracy. These methods can detect multiple pathogens simultaneously, enabling the diagnosis of co-infections and mixed infections. These are less prone to contamination than conventional methods, reducing the risk of false positives. These methods enable the rapid and accurate detection and identification of pathogens, enabling early diagnosis and treatment of diseases. Molecular methods have high specificity, sensitivity, speed, and the ability to detect multiple pathogens simultaneously. These are likely to continue to play an increasingly important role in disease diagnosis in the future, as new technologies and techniques continue to be developed.