Innovators
Frederick Sanger
Being born to a family with medical workers in Rendcombe, England, Frederick Sanger’s father had decided that his son would definitely be a part of the medical field as well. However, as time went on, Sanger fall in love with nature and also connected to science, he had no interests in medicine. He believed he was a problem solver. After a significant amount of time in his career, Sanger moved to Cambridge in 1962 at the Laboratory of Molecular Biology where he met other scientists working with problems relating to DNA. He worked on protein sequencing which came to be related to DNA sequencing. Instead of working with DNA however, Sanger chose to work RNA for their smaller size. He came to develop the dideoxy method in which one percent of the dideoxy substance is added to the DNA fragments been sequenced so that it causes their termination. In 1980, Sanger received a Nobel Prize for his discovery and went on to work with Walter Gilbert which further propelled this field because more methods continued to be developed.
Companies
Thermofisher Scientific Inc.
Mission Statement: "Thermo Fisher Scientific Inc. is the world leader in serving science, with revenues of $18 billion and more than 55,000 employees globally. Our mission is to enable our customers to make the world healthier, cleaner and safer. We help our customers accelerate life sciences research, solve complex analytical challenges, improve patient diagnostics and increase laboratory productivity. Through our premier brands – Thermo Scientific, Applied Biosystems, Invitrogen, Fisher Scientific and Unity Lab Services – we offer an unmatched combination of innovative technologies, purchasing convenience and comprehensive support".
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Thermofisher Scientific is a revolutionary Biotech platform which provides several methods to sequence DNA including whole genome sequencing, targeted sequencing, De Novo Sequencing, SNP genotyping, exome sequencing and microbial sequencing. They were involved in the first ever sequencing of the human genome and aided in the discovery of diseases such as cystic fibrosis.
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Targeted Sequencing: Targeted sequencing is an efficient way of detecting variants present in a set of genes. This method incorporates the use of the Ion PGM system as well as the Ion AmpliSeq to provide rapid ways of sequencing large amounts of data. In order to isolate the genes, either amplification through PCR procedures or hybridization methods are adopted. For shorter reads, PCR along with the Sanger Method is applied whereas for longer reads, the AmpliSeq process is used which sequences the genes in a day.
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What is the AmpliSeq Technology?
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How this Technology is Put to Use?
A thing to look out for while searching for variants are heterozygous base pairings in the DNA strand along with insertions or deletions in the DNA fragment. The steps below show targeted sequencing.
Isolate DNA: Methods depend on the handling of the DNA molecule prior to extraction and the source or tissue type involved.
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Perform PCR
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Perform Sequencing Reaction
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Purify the Sequencing Reaction: It is essential to remove dye terminators and salt to make sure it doesn't alter the results.
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Perform Capillary Electrophoresis: DNA fragments are separated by their size and detected using a laser/camera system.
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Analyze Data
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Exome sequencing takes into regard the sectors of the DNA that show sites of disease. It is unlike whole genome sequencing which sequences the entire strand of DNA. This method of sequencing provides researchers with condensed information that is more directed to their line of research. It also helps identify certain variants. The steps to this method of sequencing are as shown:
Whole Genome Sequencing: This method uses all of the processes identified above but it helps with long reads instead of short reads. It is performed on human beings, model organisms, and microbial organisms as well. Whole Genome sequencing allows for the detection of genes that are more widely dispersed across deleted or duplicated regions. This type of technology also does not require a great depth of coverage which makes it more convenient to use over a long range use.
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Microbial Sequencing: Being able to sequence using this technology allows scientists to analyze things like microbial contamination, microbial identification, environmental monitoring, as well as detecting pathogens.
Oxford Nanopore Technologies
Products:
Citations: 11.1 - 11.8
Nanopore sequencing is where the nanopore is placed against and amidst a cell membrane through which a DNA strand is allowed to pass. The nanopore itself is constructed of several micro scaffolds which allow it to adhere itself to the membrane and be able to go through extensive amounts of sequencing. Each of the scaffolds is aligned with its own electrode which all is connected to a channel in the sensor array chip which can be produced with a wide range of channels. Another device is connected to the process which is known as the Application-Specific Integrated Circuits which sets up a potential across the nanopore thus allowing it to detect whatever comes in its way and disrupts the flow of ions.
The video at the upper left corner shows the basics of Nanopore sequencing and the machines that it is later tested with. The picture at the bottom is an Application-Specific Integrated Circuit.
Exploring the Depths of Life
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Sequencing
