There are many techniques and procedures that scientists use to study DNA. One of these tools uses a group of specialized enzymes, called restriction enzymes that were found in bacteria and used as molecular scissors to cut the phosphate bonds in the molecule of DNA at specific sequences. DNA strands that have been cut with these enzymes have single stranded ends that can be joined to other DNA fragments that have the same ends. Scientists use this type of enzymes to carry out recombinant DNA technology or genetic engineering. This involves the removal of specific genes of an organism and its replacement by genes from another organism.
Another useful tool for working with DNA is a process called chain reaction (PCR), also known as PCR for translating from English (polymerase chain reaction). This technique uses an enzyme called DNA polymerase copies DNA strands in a process that simulates the way that DNA replicates naturally in the cell. This process, which has revolutionized all fields of biology, allowing scientists to obtain large numbers of copies from a particular segment of DNA.
technology called DNA fingerprinting (DNA fingerprinting) can compare DNA samples from various sources, analogous to the comparison of fingerprints. In this technique, the researchers also used restriction enzymes to break a DNA molecule into small fragments separated on a gel that subject to an electric current (electrophoresis), in this way, the fragments are sorted according to their size, since most small migrating faster than larger ones. You can thus get a banding pattern or fingerprint characteristic of each organism. A probe (labeled DNA fragment) that hybridize (it is one specifically) with some of the fragments obtained and, after exposure to X-ray film, you get a DNA fingerprint, ie a pattern of black bands characteristic for each type of DNA.
A procedure called DNA sequencing to determine the precise order of nucleotide bases (sequence) of a DNA fragment. Most types of DNA sequencing based on a technique called primer extension (first extension) developed by British molecular biologist Frederick Sanger. In this technique performs a replication of specific DNA fragments, so that the end of the fragment shows a fluorescent form of the four nucleotide bases. Modern DNA sequencers based on the idea of \u200b\u200bAmerican molecular biologist Leroy Hood, incorporating computers and lasers in the process.
scientists have completed sequencing the genetic material of microorganisms including bacteria Escherichia coli. In 1998 he undertook the challenge of sequencing the genome of a multicellular organism, a nematode worm known as Caenorhabditis elegans. In 2000, cracked the genetic material of the fruit fly (Drosophila melanogaster) and plant Arabidopsis thaliana, among others. But the most important, within this research group was the unraveling of the human genome conducted in February 2001, independently, by the international public consortium Human Genome Project and the private company Celera Genomics. APPLICATIONS
The investigation of DNA has a significant impact, especially in the field of medicine. Through recombinant DNA technology, scientists can modify microorganisms that come to convert into real factories to produce large quantities of useful substances. For example, this technique has been used to produce insulin (necessary for diabetes patients) or interferon (useful in the treatment of cancer.) The human DNA studies also reveal the existence of genes associated with specific diseases such as cystic fibrosis and certain cancers. This information can be useful for preventive diagnostics of various types of diseases.
Forensic medicine uses techniques developed in the course of research on DNA to identify criminals. Samples of DNA taken from semen, skin or blood in the crime scene are compared with the DNA of the suspect, the result is a test that can be used in court. See DNA testing.
DNA research taxonomists also helps to establish the evolutionary relationships among animals, plants and other life forms, as the phylogenetically closest species have similar DNA molecules to each other than when compared to more evolutionarily distant species. For example, American vultures are more closely related to storks than to the vultures of Europe, Asia or Africa, despite morphological and behavioral are more similar to the latter.
agriculture and animal husbandry techniques now make use of known DNA manipulation as genetic engineering and biotechnology. Strains of cultivated plants to which genes coding can yield larger crops or be more resistant to insects. Even animals have been subjected to such interventions for breeds with higher milk or meat or pig breeds richer in meat and less fat.
Another useful tool for working with DNA is a process called chain reaction (PCR), also known as PCR for translating from English (polymerase chain reaction). This technique uses an enzyme called DNA polymerase copies DNA strands in a process that simulates the way that DNA replicates naturally in the cell. This process, which has revolutionized all fields of biology, allowing scientists to obtain large numbers of copies from a particular segment of DNA.
technology called DNA fingerprinting (DNA fingerprinting) can compare DNA samples from various sources, analogous to the comparison of fingerprints. In this technique, the researchers also used restriction enzymes to break a DNA molecule into small fragments separated on a gel that subject to an electric current (electrophoresis), in this way, the fragments are sorted according to their size, since most small migrating faster than larger ones. You can thus get a banding pattern or fingerprint characteristic of each organism. A probe (labeled DNA fragment) that hybridize (it is one specifically) with some of the fragments obtained and, after exposure to X-ray film, you get a DNA fingerprint, ie a pattern of black bands characteristic for each type of DNA.
A procedure called DNA sequencing to determine the precise order of nucleotide bases (sequence) of a DNA fragment. Most types of DNA sequencing based on a technique called primer extension (first extension) developed by British molecular biologist Frederick Sanger. In this technique performs a replication of specific DNA fragments, so that the end of the fragment shows a fluorescent form of the four nucleotide bases. Modern DNA sequencers based on the idea of \u200b\u200bAmerican molecular biologist Leroy Hood, incorporating computers and lasers in the process.
scientists have completed sequencing the genetic material of microorganisms including bacteria Escherichia coli. In 1998 he undertook the challenge of sequencing the genome of a multicellular organism, a nematode worm known as Caenorhabditis elegans. In 2000, cracked the genetic material of the fruit fly (Drosophila melanogaster) and plant Arabidopsis thaliana, among others. But the most important, within this research group was the unraveling of the human genome conducted in February 2001, independently, by the international public consortium Human Genome Project and the private company Celera Genomics. APPLICATIONS
The investigation of DNA has a significant impact, especially in the field of medicine. Through recombinant DNA technology, scientists can modify microorganisms that come to convert into real factories to produce large quantities of useful substances. For example, this technique has been used to produce insulin (necessary for diabetes patients) or interferon (useful in the treatment of cancer.) The human DNA studies also reveal the existence of genes associated with specific diseases such as cystic fibrosis and certain cancers. This information can be useful for preventive diagnostics of various types of diseases.
Forensic medicine uses techniques developed in the course of research on DNA to identify criminals. Samples of DNA taken from semen, skin or blood in the crime scene are compared with the DNA of the suspect, the result is a test that can be used in court. See DNA testing.
DNA research taxonomists also helps to establish the evolutionary relationships among animals, plants and other life forms, as the phylogenetically closest species have similar DNA molecules to each other than when compared to more evolutionarily distant species. For example, American vultures are more closely related to storks than to the vultures of Europe, Asia or Africa, despite morphological and behavioral are more similar to the latter.
agriculture and animal husbandry techniques now make use of known DNA manipulation as genetic engineering and biotechnology. Strains of cultivated plants to which genes coding can yield larger crops or be more resistant to insects. Even animals have been subjected to such interventions for breeds with higher milk or meat or pig breeds richer in meat and less fat.
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