Genomics is the study of the collective genetic material in an organism. This scientific discipline is focused on sequencing the DNA in an organism to form a complete picture, and then identifying specific genes in that sequence which could be of interest. Genomics got its start in the 1970s, when scientists first began genetic sequencing of simple organisms, and it really took off as a field in the 1980s and 1990s, with the advent of scientific equipment to assist researchers.
By sequencing the entire DNA pattern of an organism, scientists can glean a great deal of information. Complete sequences can be compared, for example, to get more information about how creatures survive in different environments. A genetic sequence can also be used as a reference base for studying other members of the same species, and for identifying genetic defects, inherited conditions, and other matters of interest, such as the expression of proteins and the role of “junk” DNA in the body.
In genomics, scientists analyze the DNA in every chromosome of the organism of interest. When a completely sequenced set of DNA has been created, this set is collectively known as a “genome.” The genomes of numerous species have been sequenced, from bacteria to humans. The genome of each species is distinctly different, with varying numbers of nucelotides which can translate into huge amounts of information. Within a species, genetic variation may be minimal, but still interesting, because it can explain certain traits or tendencies.
This scientific discipline is different than the study of genetics, which focuses on specific genes and what they do. Some genetics is certainly involved in genomics; for example, a scientist might want to know more about the specific location of a gene within an organism's genome, in which case he or she would use genomics techniques. Genomics looks at the collective role and function of an organism's genome, not necessarily the behaviors of individual sections.
In 2003, scientists succeeded in sequencing the entire human genome. Numerous other organisms had been sequenced by that time, and more are sequenced every year. Now that scientists can examine the human genome as a whole, they can start to see the complex relationships between genes and fragments of DNA, and they can identify areas which might benefit from further study. The unraveling of the human genome also yielded some interesting surprises, like more information about the role of the so-called extra X chromosome in women.