Editing Genomics and Transcriptomics (section)

== 2. Transcriptomics: Reading the Cellular Output ==

While the genome is the static blueprint (virtually identical in every cell of an organism), the transcriptome is highly dynamic. Transcriptomics is the study of all messenger RNA (mRNA) transcripts produced by a cell at a specific moment. It tells us not just what genes a cell ''has'', but which genes it is actively ''using''.

Researchers rely on two primary technologies to study the transcriptome:
* '''RNA-Sequencing (RNA-Seq):''' Utilizes NGS technology to sequence the entire transcriptome. It provides high resolution and can discover novel transcripts or alternative splicing events that microarrays might miss.
* '''DNA Microarrays:''' A slightly older but highly efficient technology. A solid surface (a "chip") is spotted with thousands of known, single-stranded DNA probes. Fluorescently labeled cDNA (synthesized from the sample's RNA) is washed over the chip. If a specific gene is being expressed, its cDNA will hybridize (bind) to the corresponding probe on the chip, creating a fluorescent signal.