cDNA Cloning
	• Inserts are derived from mature mRNA molecules (polyA +) isolated from a tissue or group of cells • These correspond to the transcribed genes – The relative number of different mRNAs reflect the levels of transcription and turnover in the cell • Single stranded mRNA is copied by reverse transcriptase into double stranded cDNA • cDNA libraries representing specific cell types or developmental stages are constructed in plasmid vectors