The ’90s ushered in the era of whole-genome sequencing (WGS), starting with Haemophilus influenza1 and culminating in completion of the Human Genome Project in 2003. The DNA library preparation step in WGS greatly benefited from thermal cycler advancements which allowed:
- Greater control of evaporation and condensation—for better sample integrity
- Better control over heating and cooling— for temperature uniformity
- More compact, “benchtop” thermal cycling
Whole Genome Sequencing workflow courtesy of the CDC: https://www.cdc.gov/pulsenet/pathogens/wgs.html
Several exciting thermal cycler innovations made these benefits possible and were incorporated into the GeneAmp™ family of thermal cyclers:
- Heated lid: Prior to heated lids, mineral oil was used to prevent evaporation and condensation. A heated lid was developed to achieve an oil-free – and less messy — PCR experiment with
The GeneAmp PCR System 9700, commercialized in 1997, had one of the first solid-state Peltier cooling systems.
minimal evaporation.
- Algorithm to control sample temperature: A complex mathematical model was developed for better temperature regulation and uniformity of the PCR sample. This innovation measured the temperature of the sample itself versus the temperature of just the thermal block.
- Solid-state Peltier cooling system: Previous cooling systems used a bulky plumbing compressor. The development of a solid-state Peltier cooling system resulted in a smaller (benchtop) device with more efficient cooling.
- Interchangeable sample blocks: The GeneAmpTM PCR System 9700 was introduced with interchangeable sample blocks on a common base module, which provided flexibility to meet customer demands for different experiment run times and throughput.
The innovations that inspired and made the GeneAmp PCR System possible paved the way for discoveries that have revolutionized science, including:
– In 1995, C. Venter published the first completely sequenced genome of a free-living organism Haemophilus influenza 1 using the GeneAmpTM PCR System 9600. The speed and accuracy of whole-genome random sequencing dramatically accelerated large-genome sequencing, culminating with the completion of the human genome project.
– In 1996, the chemokine receptor CCR5 was identified2 as the coreceptor for HIV infection using the GeneAmpTM PCR System 2400. The discovery of CCR5 resolved two outstanding questions in HIV research: “How HIV infected human cells?” and “Why some individuals were immune to infection?”
Learn more at thermofisher.com/30yearsofinnovation
For Research Use Only. Not for use in diagnostic procedures.
1 Fleischmann R.D. et al. Whole-genome random sequencing and assembly of Haemophilus influenzae Rd. Science 269, 496-512 (28 July, 1995).
2 Dragic T. et al. HIV-1 entry into CD4+ cells is mediated by the chemokine receptor CC-CKR-5. Nature 381, 667-673 (20 June, 1996).
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Kenneth Tan, Sr. Product Manager, Thermo Fisher Scientific
Kenneth has 20 years of experience with PCR-related products. He began his career as a project engineer, responsible for thermal cycler technology transfer to manufacturing. He moved into the development of thermal cyclers as an R&D system engineer, and then managed PCR and qPCR thermal cycler programs. Currently, he is a thermal cycler and PCR plastics product manager.
Kenneth holds patents related to Applied Biosystems™ VeriFlex™ temperature control technology, and patents related to thermal cycler temperature uniformity.
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