Synthesis of complementary DNA (C-DNA): Principles, methodology, and applications in gene expression studies

Complementary DNA (cDNA) synthesis from RNA is a pivotal technique in molecular biology that enables the conversion of RNA molecules into DNA copies (Gubler, and Hoffman, 1983). This process holds immense significance in various research fields, including gene expression analysis, functional genomics, and molecular cloning. By synthesizing cDNA from RNA templates, researchers can access a stable DNA form of RNA sequences, allowing for easier manipulation, amplification, and analysis (Green, and Sambrook, 2012). The synthesis of cDNA from RNA involves the reverse transcription (RT) of RNA molecules using a specialized enzyme called reverse transcriptase (Okayama, and Berg, 1982). This enzyme catalyzes the synthesis of DNA strands complementary to the RNA template. Through this process, the genetic information contained within RNA molecules can be preserved and further analyzed using various molecular techniques commonly applied to DNA (Srivastava et al., 2022). cDNA synthesis plays a crucial role in numerous experimental procedures, such as gene expression profiling using techniques like quantitative reverse transcription PCR (qRT-PCR) and RNA sequencing (RNA-seq) (Brown, 2010; Tripathi et al 2013a,b). Additionally, cDNA libraries constructed from specific tissues, cells, or organisms serve as valuable resources for studying gene expression patterns, identifying novel transcripts, and understanding cellular processes at the molecular level.