In the simplest of terms, DNA, or deoxyribonucleic acid, is the genetic code that determines all the characteristics of a living thing. This double, long chain of molecules called nucleotides tell each cell what proteins to make, giving them the genetic instruction guide for life and its processes. Each cell’s development, reproduction and death are controlled by the instructions contained in DNA.
In the 1970s, the first DNA sequences were obtained by academic researching using slow, labor-intense methods.
In 1990, the Human Genome Project was launched. This 13-year international effort was, oddly enough, led by the U.S. Department of Energy. The Human Genome Project’s goal was to provide a complete and accurate sequence of the 3 billion DNA base pairs that make up the human genome and to find all of the estimated 20,000 to 25,000 human genes. The Project also aimed to sequence the genomes of several other organisms that are important to medical research, such as the mouse and the fruit fly.
DNA sequencing enables researchers to identify DNA patterns in fingerprints, saliva, hair follicles and other cells so that they can uniquely separate each living organism from another. Every living organism ever created has a one of a kind DNA pattern, which can be determined through DNA testing. It is extremely rare that two people have exactly the same DNA pattern.
With the development of the advanced fluorescence-based sequencing, DNA sequencing technology has vastly improved in recent years. Sequencing the first human genome cost about $1 billion and took 13 years to complete; today it costs about $3,000 to $5000 and takes just one to two days.
DNA sequencing is the process of determining the order of nucleotide in DNA. This indispensable information is key to basic biological research for making medical diagnoses, for use in forensic biology, virology, anthropology and other applied fields.
DNA sequencing may be used to determine the sequence of individual genes, larger genetic regions, full chromosomes, or entire genomes of any organism. In molecular biology, sequencing is used to enable researchers to identify changes in genes, associations with diseases and help identify potential drug targets.
Oncologist and patients benefit from the knowledge researchers have gained over the last several decades about DNA sequencing. When cancer is diagnosed, DNA samples are collected and are tested for DNA mutations that give insight to oncologists for heading off cancer before it becomes life threatening to their patients. Since each person’s cancer has a unique combination of genetic changes, tumor DNA sequencing identifies these unique DNA changes. In some cases, knowledge of the genetic alterations in a cancer can help determine a treatment plan.