The quartz wafer is in the holding position on the DNA synthesizer. The wafer is moved to a vertical reaction vessel for the process of DNA chain elongation.
Affymetrix, the makers of GeneChip arrays.
Here you can see a technician shuttling a quartz wafer (containing 50-400 GeneChips) between alternating photolithography and DNA synthesis steps.
A technician uses a computer guiding system to align the filter mask in perfect register with the quartz wafer. The filter mask will block light to selected regions of the wafer. More nucleotides can be added to the exposed regions.
Here a technician aligns a quartz wafer, from which 50-400 GeneChips are prepared for mounting.
Synthesizing human insulin using recombinant DNA, 3D animation with no audio
In the 1990s, DNA arrays provided the means to analyze patterns of gene expression at different timepoints in a living cell.
Two sequencing techniques were developed independently in the 1970s. The method developed by Fred Sanger used chemically altered "dideoxy" bases to terminate newly synthesized DNA fragments at specific bases (either A, C, T, or G). These fragments are th
DNA profiling, DNA fingerprinting.
DNA fingerprints are also known as DNA profiles. They are now made using probes that detect differences in the number of short tandem repeats (STRs) between individuals.