In the past decade, DNA sequencing technologies have evolved at an unprecedented pace, thus deeply changing the landscape of genomics.
Thanks to a combination of biology, genetics, science and high-throughput methods by DNA sequencing it is possible to have a complete access to the information present in your DNA and, what’s more, learn your risk of exposure to a few diseases.
Indeed, new systems and platforms, fast evolving methodologies, bioinformatics and innovative application of Next Generation Sequencing in combination with other technologies, have enabled study of numerous genetic factors complexly affecting the health of individuals.
By definition, DNA sequencing is the process of reading the succession of letters of a given DNA fragment. To be more precise, it determines the order of the four building blocks, called “bases” (A adenine, T thymine, C cytosine and G guanine) that make up the DNA molecule.
Basically, to perform DNA sequencing, you extract DNA from a biological sample (usually blood or saliva) and a scientific instrument, called a sequencer, decodes it. Then, DNA is compared with the reference human genome gathered by researchers within the international project called Human Genome Project. The research program was to complete genome mapping and understanding of all the genes of human beings and establish the reference for human genome, that is, what is common to the human species.
By decoding the message present in our genes, scientists have been able to identify, diagnose and potentially find treatments for genetic diseases, such as hereditary forms of cancer.
But let’s tell the history from the very beginning: it was a British biochemist Frederick Sanger, who won the Nobel Prize in chemistry twice (in 1958 and in 1980), who developed the first DNA sequencing method. This pioneering technique, known as “polymerase chain termination method”, was slow and expensive so it gave way to faster, low-cost, modern technologies.
In order to sequence longer sections of DNA, a new approach called “shotgun sequencing” was developed during Human Genome Project. It is named by analogy with the rapidly expanding firing pattern of a shotgun. In this method, genomic DNA is mechanically broken down into smaller fragments which can be sequenced individually. They are then assembled together by computer programs which find where fragments overlap.
Tremendous progress has also been made in terms of speed, read length and throughput along with a sharp reduction in cost.
Next-Generation Sequencing (NGS) technology has triggered a true revolution in terms of knowledge of human genome and has set the basis for predictive medicine. It has demonstrated the capacity to sequence DNA at unprecedented speed, thereby enabling previously unimaginable scientific achievements and novel biological applications.
The ultra-high-throughput and accuracy of NGS expanded countless possibilities of genome-scale assays in clinical, medical, cancer and basic research, screening large numbers of samples for changes underpinning diseases.
Because of its high throughput, precision and reliability, Next-Generation Sequencing is the technology chosen by Genoma to perform its pipeline of exclusive genetic tests, including screening for trisomies 21, 18, 13, sex chromosome aneuploidies and microdeletions, ovarian and breast cancer risk screening, inherited disorders detection.