All living things store genetic information either through DNA or RNA. In the human body, every cell contains a copy of approximately 3 billion DNA base pairs that make up the human genome. The genome contains all the information needed for a human to develop and function. Within a strand of DNA are things called genes, these are small sections of the DNA that hold specific instructions for making a single or multiple proteins. From our eye color to our levels of hormones, our DNA makes us who we are.
Genomics vs. Genetics
Put simply, genomics studies an organism's genetic material, its genome, and how this material is structured, functions, and evolves. Furthermore, genomics works towards mapping and editing full genomes. It looks at how multiple genes impact a certain form of expression and the interaction between genes. Genomics contrast genetics, which is the study of an individual gene and its role in inheritance. In other words, genetics aims to discover how certain traits are passed down through genes from one generation to the next.
During the late 1970s and 1980s, Fred Sanger's and his group established genome mapping and sequencing. This development of technology led to the human genome project in the 1990s, which completed the human genome sequence in 2003. This project combined several individual genomes to create a generic sequence of the entire human genome. This information has provided the resources to identify genetic variations that increase risk for diseases. From here, scientists began to develop new and innovative technologies which have lead to what we know as genomics today.
Areas of Genomics
There are many areas within the field of genomics, here are a few of the most commonly practiced;
- Functional Genomics: Collects and uses data from sequencing genomes to describe the interactions and functions of genes and proteins.
- Structural Genomics: Determines the structure of a protein encoded by a certain gene.
- Epigenomics: Studies how changes in gene expression can impact an organism.
- Comparative Genomics: Compares genomic features between different organisms.
Genomic sequencing determines the exact order of the bases in a strand of DNA. This type of test looks for any changes, also called variants, in genes and how these changes affect an individual's health. The first step to genomic sequencing is taking a sample of either blood, saliva, or tissue. The DNA from the given sample is tested by a computer program which writes out the code of the DNA. From here, experts analyze the DNA in large sequences to inspect for any variants. If anything is found to be abnormal, it is further looked into to determine if the abnormality is a risk or reason for a specific health condition.
So far, according to WHO, genomics has already allowed for “improvements in diagnostics, more effective therapeutic strategies, evidence-based approaches for demonstrating clinical efficacy, and better decision-making tools for patients and providers.” With these advancements being made early in the development of genomics, medical professionals have started to predict where this field is headed. One of these predictions involves a more patient centric approach in the field of precision medicine. Meaning, we are getting closer to successfully being able to create personalized drugs for patients, this is known as pharmacogenomics.
Pharmacogenomics combines the study of an individual's genes and their responses to drugs. When studying the genome of an individual, we are able to determine if any variants are present. This then allows experts to predict how effective a medication will be and determine proper dosages to prevent adverse drug reactions.