Down to the Sea on (Gene) Chips: The Genomics Revolution Is Transforming the Way Scientists Can Study Life in the Oceans

By Hahn, Mark E. | Oceanus, Fall-Winter 2005 | Go to article overview
Save to active project

Down to the Sea on (Gene) Chips: The Genomics Revolution Is Transforming the Way Scientists Can Study Life in the Oceans


Hahn, Mark E., Oceanus


A half-century ago, James Watson and Francis Crick (aided by Rosalind Franklin and Maurice Wilkins) discovered the double-helical structure of deoxyribonucleic acid (DNA). Other scientists soon showed how DNA--through a triplet code of nucleotide bases on the DNA "spiral staircase" and through ribonucleic acid (RNA) intermediaries--instructs cells to assemble essential life-sustaining proteins. These discoveries opened the door to a new understanding of life by revealing the genetic "blue-prints" that underlie the ability of organisms to grow, survive, and reproduce.

A revolution in biotechnology ensued, giving scientists methods to isolate and identify genes, make millions of copies of them, and determine their sequences of nucleotide bases. Together, the accelerating pace of biotechnological advances and the exponential increase in DNA sequence information ignited an explosion in molecular biology and led to the emergence of a new field: genomics. These advances were initially applied in the biomedical arena, leading to new information on the genes responsible for heritable diseases, the molecular signatures of cancer cells, the biology of human pathogens, and genetic factors that influence an individual's sensitivity to drugs or toxicants.

Now, the genomics revolution has reached the oceans. New genomic techniques are being used to find previously unknown life forms in the oceans; to learn how species, and genes themselves, evolved over Earth's long history; to understand the genetic tools that allow species to adapt to diverse and often harsh environments; and to investigate species' responses to pollutants. Genomics gives marine scientists powerful new ways to address age-old questions about life in the oceans.

What is genomics?

Genomics is more than simply determining the sequence of nucleotides in an organism's genome (the entire set of genetic information contained within a cell's DNA). It is a new approach to questions in biology, distinguished from traditional approaches by its scale. Rather than studying genes one by one, genomic approaches involve the systematic gathering and analysis of information about multiple genes and their evolution, functions, and complex interactions within networks of genes and proteins.

Genomics has two branches. One is structural genomics--studies of how genes and genomes are organized and how that varies among individuals, populations, and species. It includes characterization of the sequences of DNA nucleotides that encode proteins, as well as the DNA found between and within genes that does not code for proteins.

Using structural genomics, we can compare DNA sequences among individuals of a species to reveal minor variations in the DNA nucleotide code at certain positions in the genome, called "single-nucleotide polymorphisms," or SNPs (pronounced "snips"). These SNPs can be responsible for genetic diseases, or for hypersensitivity or resistance to drugs or toxicants.

By comparing DNA sequences among species (called "comparative genomics"), scientists can identify changes in genomes that have occurred as species evolved. They can also begin to determine the function of specific DNA sequences shared among different species.

The second branch is functional genomics--the study of the RNA and proteins produced by genes (referred to as "gene expression"), and how these molecules interact to carry out cellular processes.

Among the most elegant and widely used tools of functional genomics is the microarray, or "gene chip" (see figure), which became available less than a decade ago. By using microarrays to simultaneously measure the amounts of hundreds or thousands of specific RNAs contained in cells or tissues, biologists can "see" what cells are doing and how they are responding to particular environmental conditions.

Genes reveal marine biodiversity

Though the genomics revolution immediately swept into biomedical research, its entrance into oceanography and marine biology lagged.

The rest of this article is only available to active members of Questia

Sign up now for a free, 1-day trial and receive full access to:

  • Questia's entire collection
  • Automatic bibliography creation
  • More helpful research tools like notes, citations, and highlights
  • Ad-free environment

Already a member? Log in now.

Notes for this article

Add a new note
If you are trying to select text to create highlights or citations, remember that you must now click or tap on the first word, and then click or tap on the last word.
Loading One moment ...
Project items
Notes
Cite this article

Cited article

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited article

Down to the Sea on (Gene) Chips: The Genomics Revolution Is Transforming the Way Scientists Can Study Life in the Oceans
Settings

Settings

Typeface
Text size Smaller Larger
Search within

Search within this article

Look up

Look up a word

  • Dictionary
  • Thesaurus
Please submit a word or phrase above.
Print this page

Print this page

Why can't I print more than one page at a time?

While we understand printed pages are helpful to our users, this limitation is necessary to help protect our publishers' copyrighted material and prevent its unlawful distribution. We are sorry for any inconvenience.
Full screen

matching results for page

Cited passage

Style
Citations are available only to our active members.
Sign up now to cite pages or passages in MLA, APA and Chicago citation styles.

Cited passage

Welcome to the new Questia Reader

The Questia Reader has been updated to provide you with an even better online reading experience.  It is now 100% Responsive, which means you can read our books and articles on any sized device you wish.  All of your favorite tools like notes, highlights, and citations are still here, but the way you select text has been updated to be easier to use, especially on touchscreen devices.  Here's how:

1. Click or tap the first word you want to select.
2. Click or tap the last word you want to select.

OK, got it!

Thanks for trying Questia!

Please continue trying out our research tools, but please note, full functionality is available only to our active members.

Your work will be lost once you leave this Web page.

For full access in an ad-free environment, sign up now for a FREE, 1-day trial.

Already a member? Log in now.

Are you sure you want to delete this highlight?