14.2: Expression Microarrays
- Page ID
- 40996
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Prior to the development of mRNA sequencing technology, mRNA levels were measured using expression microarrays. These microarrays function by inserting a DNA probe on a slide and measuring the levels transcripts that undergo complimentary hybridization with the DNA, a process that could analyze expression on a gene by gene basis (Figure 1).
Figure 14.1: Figure 1: Expression microarray process
However, this technology has several limitations: it cannot distinguish mRNA isoforms, it cannot analyze on the sequence, or digital level, it can only measure known transcripts, and the expression measurements become less reliable for highly saturated transcript levels.