Here, we will try to explain what exactly a genome is and what the function of genome sequencing is. We will also try to provide a chronology of events that have helped advance the science of genomics since the 1970s.
What's a Genome?
Genome is a fancy word for all our DNA. From potatoes to puppies, all living organisms have their own genome. Each genome contains the information needed to build and maintain that organism throughout its life.
In other words, the genome is the operating manual containing all the instructions that helped one develop from a single cell into the person they are today. It guides one’s growth, helps their organs do their jobs, and repairs itself when it becomes damaged.
A gene is a segment of DNA that provides the cell with instructions for making a specific protein, which then carries out a particular function in our bodies. Nearly all humans have the same genes arranged in roughly the same order, and more than 99.9% of one person’s DNA sequence is identical to any other human. Still, we are different. On average, a human gene will have 1-3 letters that differ from person to person. These differences are enough to change the shape and function of a protein, how much protein is made, when it's made, or where it's made. They affect the colour of one’s eyes, hair, and skin. More importantly, variations in one’s genome also influence his or her risk of developing diseases and one’s responses to medications.
What's genome sequencing?
Genome sequencing is a scientific method that is used to determine the entire genetic makeup of a specific organism. This method can be used to find changes in areas of the genome. These changes may help scientists understand how specific diseases, such as cancer, form. The results of genomic sequencing can also be used to diagnose and treat diseases.
Genome sequencing improves the knowledge available to researchers interested in evolutionary biology and, hence, lays the foundation for predicting disease susceptibility and drug response.
The Human Genome Project (HGP) was the most important biomedical research project of the 20th century. In many ways, it challenged some of the fundamental understandings of scientific inquiry that had stood for centuries. The completion of the project in 2003 and subsequent boom in the genomics field have had a profound impact not just on biology and medicine but also on ethics and society. The project also changed traditional understandings of how and why scientific research is conducted.
The HGP is one of the greatest scientific feats in history. The project was a voyage of biological discovery led by an international group of researchers looking to comprehensively study all of the DNA (known as a genome) of a select set of organisms. Launched in October 1990 and completed in April 2003, the Human Genome Project’s signature accomplishment—generating the first sequence of the human genome—provided fundamental information about the human blueprint, which has since accelerated the study of human biology and improved the practice of medicine.
The DNA sequencing methods used in the 1970s and 1980s were manual, for example, Maxam-Gilbert sequencing and Sanger sequencing. Several whole bacteriophage and animal viral genomes were sequenced by these techniques, but the shift to more rapid, automated sequencing methods in the 1990s facilitated the sequencing of the larger bacterial and eukaryotic (animals, plants, fungi, etc.) genomes.
The first virus to have its complete genome sequenced was Bacteriophage MS2 by 1976. The first organism whose entire genome was fully sequenced was Haemophilus influenzae, a bacterium, in 1995.
Over the years, Bangladeshi scientists have made their share of contributions to genomics too. They worked on unravelling genetic makeups of certain types of jute, jackfruit, water buffaloes, etc. Scientists in Bangladesh are also working on varietal developments in crops by applying gene-editing tools.
