Genomics is the study of human genes and chromosomes. The human genome typically consists of 23 pairs of chromosomes and 24,000 genes. In medicine, genome and DNA sequencing -- determining the exact structure of a DNA molecule -- are done to learn more about a patient's molecular biology.
Genomic studies uncover the genetic makeup of patients, including their genetic differences and mutations. All of that information can be used to form a care plan specific to patients' individual genetic composition, rather than treating them with a one-size-fits-all approach.
What genomics is used for
There are many applications for human genetics in medicine, biotechnology, anthropology and other social sciences.
In medicine, next-generation genomic technology can collect increased amounts of genomic data. When this data is combined with informatics, it enables the integration of all this information. Doing so better enables researchers to understand drug response and disease based on genetics and also helps in the efforts to achieve personalized medicine.
Mapping a human genome is time-consuming and produces a terabyte (TB) of unorganized data. As technology advances and that data becomes easier to store and comprehend, more healthcare providers will use it to diagnose and treat patients and create clinical decision support.
Strides have been made in genome sequencing efficiency. It took Nationwide Children's Hospital in Columbus, Ohio, one week to analyze the same data set that was studied over 18 months during the 1,000 Genomes Project. That project was the first to sequence the genomes of a large group, an endeavor that could benefit population health management.
Some pilot projects have targeted integrating genomics capabilities into providers' electronic health record (EHR) systems as their goal. Genomics is considered part of personalized or precision medicine, a model of healthcare in which providers customize treatment to fit each individual patient's needs and genetic configuration.
Genomics relies on DNA sequencing
Whole genome sequencing entails determining the complete DNA sequence of an organism's genome.
In order to do this, an organism's chromosomal DNA (and the DNA contained in the mitochondria and the chloroplast for plant studies) must all be sequenced.
To sequence a genome, it must first be broken into lots of small pieces, and then the sequence of each small piece of DNA must be determined in order to figure out which pieces fit together.
Original DNA sequencing centered on analytical chemistry and molecule separation techniques to determine the order of the sequence. People analyzed the sequences, which took up a lot of time.
Evolutions in these techniques sped the process up, along with advances in machines that allowed far more DNA strands to be read at the same, partially thanks to automation and imaging technology. Today, sequencing instruments are also smaller and cheaper to use.
With that sequencing comes massive amounts of genomic data -- perhaps 1 TB of data for a human genome. As a result, storage technology also plays a part in genomics from a practical standpoint.
"Over the years, innovations in sequencing protocols, molecular biology and automation increased the technological capabilities of sequencing while decreasing the cost, allowing the reading of DNA hundreds of basepairs in length, massively parallelized to produce gigabases of data in one run," according to an article in the journal Genomics in 2016.
Types of genomics
People are studying and experimenting with genomics for many different purposes. Here are examples of the different types of genomics:
- Structural genomics: Aims to determine the structure of every protein encoded by the genome.
- Functional genomics: Aims to collect and use data from sequencing for describing gene and protein functions.
- Comparative genomics: Aims to compare genomic features between different species.
- Mutation genomics: Studies the genome in terms of mutations that occur in a person's DNA or genome.
Genomics and family assessments
Family health history can often reveal important risk factors for common and chronic diseases.
Creating a family history is an important part of preventive medicine as well as public health. Experts believe that family history assessments have several advantages, including lowering the cost of providing care, and a reflection of shared genetic and environmental risk factors.
Performing genomic studies on family members can provide further clues on what diseases a family's gene pool may be more susceptible to.
Genomics, genetics and proteomics
It is common for people ask about genomics vs. genetics and how they differ. The main difference is that genetics looks at how genes and their traits are inherited, while genomics looks at all genes -- in other words, the genome -- as well as their inter-relationships to identify their combined influence on the growth and development of the organism.
Proteomics is the study of the entire protein set -- the proteome -- coded by the genome of an organism or a cell type.
While the genome in an organism is constant, the proteome varies. And while every cell in an organism has the same set of genes, the set of proteins produced differ and are dependent on gene expression.
Brief history of genomics
DNA was first isolated as early as 1869, with technological advances happening in the 1950s, such as creating isotopes and radiolabel biological molecules. Also during this time, the description of the structure of the DNA helix was made by scientists James D. Watson and Francis H.C. Crick in 1953.
But the history of modern genomics really starts in the 1970s when the first genome was sequenced by biochemist Frederick Sanger. He sequenced the genomes of a virus and mitochondrion in the early 1970s. Sanger and his team also created techniques for sequencing, data storage, genome mapping and more.
Another scientist who played an important role in modern genomics is Walter Fiers. In 1972, he and his research team from the Laboratory of Molecular Biology of the University of Ghent in Belgium were the first to sequence a gene.
In 1990, the Human Genome Project, a publicly funded international genomics research effort to determine the sequence of the human genome as well as identify the genes it contains, was launched by the National Institutes of Health and the U.S. Department of Energy. The goal of this group was to sequence and identify all three billion chemical units in the human genome. The purpose of this was to find the genetic roots of disease and help develop treatments.
The Human Genome Project also aimed to make all human genome sequence information freely and publicly available within 24 hours of its assembly. The project was active for 13 years.
Former U.S. President Barack Obama announced a $215 million Precision Medicine Initiative in early 2015. The initiative aimed to tailor medical care to individuals based on their genes, lifestyles and environments. The National Cancer Institute received $70 million as part of the initiative to study cancer genomics.
Genomes evolve over time, changing in sequence or size. The study of genome evolution involves multiple fields and is constantly changing as more and more genomes are sequenced and made available to the scientific community and the public at large.