The Human Genome Project
And taking advantage of this is how the deoxy chain termination sequencing was developed. If one takes a very low concentration of a dead end inhibitor, a dideoxy A, and adds it to the reaction, perhaps 1:1000 is the ratio between the dideoxy-A and the normal deoxy-ATP, so that most of the time the base is added and that base enables an additional base to be added. But when the dideoxy base is added, that stops the chain from growing. If one has 4 separate reactions (a dideoxy A, a dideoxy G, a dideoxy C, and a dideoxy T) those separate reactions can be used to monitor the growing of the chain. What happens is that sometimes you will stop at the first available A, sometimes you will stop at the second, at the third, etc. and what happens is you end up generating a ladder. These bases were originally put in and they were radioactive so the growing chains were radioactive and the growing chains could be detected with autoradiography. So after the gel is run and a piece of radiographic film is superimposed on top of this and then developed, you can actually see the bands where the chain has terminated at the very first A, the next available G, and then you see 2 where C’s have been added. One literally reads up this ladder to determine the sequence; you can get a sequence of the growing chain from this and from that sequence you can infer the sequence of the original molecule that you started with.
Deoxy Chain Terminiation
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- How Do We Obtain Genetic Information?
- Cell Cross-Section
- Different Cell Types
- What Happens When You Sit Outside in the Sun?
- DNA is the Altered Target in Cancer Cells
- DNA Structure
- How to Tackle a Problem as Difficult as Cancer?
- Sequencing DNA
- More on DNA Structure
- Replicating a Strand of DNA
- Developing the Deoxy Chain Terminiation Sequence
- Reading a DNA Sequence
- Gel Electrophoresis
- Two DNA Sequences Seen in Gel Electrophoresis
- Overlapping Pieces of DNA
- Requirements to Sequence the Human Genome?
- Advances in Sanger Sequencing
- Sequencing with Fluorescent Dye
- Advances in Fluorescent Sequencing
- Celera Genomics
- Capacity: 96 Capillary Sequencing
- Computers and the Human Genome Project
- Where are We Today?
- What Have We Learned From Genome Sequences?
- What Can We Do With Sequenced Genomes?
- Transcriptional Profiling (TP)
- Different Technologies to Produce Microarrays
- Utilizing Microarrays to Measure Gene Expression
- Hyrbidization to an Affymetrix Array
- Gene Expression Comparison Between Samples
- Gene Expression Map
- Proteomic-Based Strategies
- Example of a Single Gene
- How Do We Quantify Proteins?
- Differentiate Between Control and Disease State
- Mass Spectrometry
- Electrospray Ionization FT-ICR Mass Spectrometer
- LC-ESI-TOF vs LC-FT-ICR Mass Spectrometry
- What's the Short-term Payoff?
- What's the Long-term Payoff?
- Diagram of Pathways Involved in Steroid Metabolism