Difference between revisions of "Genomics"
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| − | Genomics is a scientific field focused on the study of genomes and their structure, functions, and evolutionary history. A genome is the complete set of DNA that is present in each cell of a living organism. The genome is broken down into individual genes, each of which encodes a specific protein. Organisms have huge numbers of proteins that perform a variety of diverse biological functions. Mutations in | + | Genomics is a scientific field focused on the study of genomes and their structure, functions, and evolutionary history <ref> [http://www.news-medical.net/life-sciences/What-is-Genomics.aspx] </ref>. A genome is the complete set of DNA that is present in each cell of a living organism. The genome is broken down into individual genes, each of which encodes a specific protein. Organisms have huge numbers of proteins that perform a variety of diverse biological functions. Genes are encoded by a sequence of 4 different nucleotide bases, Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). Mutations or changes in this genetic code can cause defects in protein production that can lead to various disease conditions from cancer to sickle cell anemia <ref> [https://www.genome.gov/10001204/specific-genetic-disorders/] </ref>. In contrast to genetics, which tends to focus on the functions of single genes, genomics considers the full genome and larger gene networks and often considers populations and variations that arise at these broader levels. The mapping and modeling of genomes has has wide implications for the fields of medicine, molecular biology, pharmaceutical sciences, and more. Advances in DNA sequencing could change the way that many diseases are approached and treated. |
== History == | == History == | ||
| + | |||
| + | === Early DNA Sequencing === | ||
| + | After the proposal of the now accepted model of DNA structure by James Watson and Francis Crick in 1953, many efforts were made to find methods to effectively sequence DNA <ref> [http://www.nature.com/nature/dna50/watsoncrick.pdf] </ref>. The first efficient method for sequencing larger pieces of genomic DNA was developed by Frederick Sanger in the mid-1970s that became known as the Sanger Method or chain-termination method <ref> [https://www.ncbi.nlm.nih.gov/pmc/articles/PMC431765/] </ref>. This method combines the use of DNA polymerase, the enzyme that forms double-stranded DNA, with dideoxynucleotides that prevent further strand elongation once they are added. This will form strands of different length at each nucleotide position that can then be separated using gel electrophoresis. These fragments can then be assembled into a completed DNA sequence. | ||
| + | |||
| + | === Advancements in Sequencing === | ||
| + | In 1986, a major advancement was made to Sanger sequencing by the company Applied Biosystems who optimized the Sanger Method using fluorescent dyes <ref> [http://www.nature.com/scitable/topicpage/dna-sequencing-technologies-690] </ref>. Now, each dideoxynucleotide was labeled with a different color dye. This allowed for all of the DNA fragments to be run in the same lane and be read by a machine to determine the DNA sequence based on the sequence of the fragments' fluorescence. | ||
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| + | == The Human Genome Project == | ||
| + | |||
| + | |||
| + | == Ethical Issues == | ||
| + | As genetic sequencing technology continues to advance, the possibility of having someone's genome be a basic part of their medical record is becoming closer to reality. | ||
| + | |||
| + | == See Also == | ||
| + | |||
| + | == References == | ||
Revision as of 20:37, 19 February 2017
Genomics is a scientific field focused on the study of genomes and their structure, functions, and evolutionary history [1]. A genome is the complete set of DNA that is present in each cell of a living organism. The genome is broken down into individual genes, each of which encodes a specific protein. Organisms have huge numbers of proteins that perform a variety of diverse biological functions. Genes are encoded by a sequence of 4 different nucleotide bases, Adenine (A), Thymine (T), Cytosine (C), and Guanine (G). Mutations or changes in this genetic code can cause defects in protein production that can lead to various disease conditions from cancer to sickle cell anemia [2]. In contrast to genetics, which tends to focus on the functions of single genes, genomics considers the full genome and larger gene networks and often considers populations and variations that arise at these broader levels. The mapping and modeling of genomes has has wide implications for the fields of medicine, molecular biology, pharmaceutical sciences, and more. Advances in DNA sequencing could change the way that many diseases are approached and treated.
Contents
History
Early DNA Sequencing
After the proposal of the now accepted model of DNA structure by James Watson and Francis Crick in 1953, many efforts were made to find methods to effectively sequence DNA [3]. The first efficient method for sequencing larger pieces of genomic DNA was developed by Frederick Sanger in the mid-1970s that became known as the Sanger Method or chain-termination method [4]. This method combines the use of DNA polymerase, the enzyme that forms double-stranded DNA, with dideoxynucleotides that prevent further strand elongation once they are added. This will form strands of different length at each nucleotide position that can then be separated using gel electrophoresis. These fragments can then be assembled into a completed DNA sequence.
Advancements in Sequencing
In 1986, a major advancement was made to Sanger sequencing by the company Applied Biosystems who optimized the Sanger Method using fluorescent dyes [5]. Now, each dideoxynucleotide was labeled with a different color dye. This allowed for all of the DNA fragments to be run in the same lane and be read by a machine to determine the DNA sequence based on the sequence of the fragments' fluorescence.
The Human Genome Project
Ethical Issues
As genetic sequencing technology continues to advance, the possibility of having someone's genome be a basic part of their medical record is becoming closer to reality.
