The advances in genotyping and functional genomics open new approaches to environmental science, including public health issues. A better understanding of epigenetics, for example, could reveal environmental triggers of cancer and other diseases. Here, experts in the field describe the most exciting advances in these areas and the best training to land a job.
Harvard School of Public Health http://www.hsph.harvard.edu
Oak Ridge National Laboratory http://www.ornl.gov
University of California, Berkeley http://www.berkeley.edu
University of Miami http://www.miami.edu
The technologies behind today’s genetics and genomics provide powerful tools for some obvious fields, such as medicine, but other fields can also benefit from these molecular capabilities. Environmental science looks particularly ripe for these applications. Genetic and genomic tools can enhance environmental research that ranges from traditional areas, like natural history and population genetics, to translational areas, such as public health. As a result, scientists who possess these tools can build careers in environmental research through many organizations.
First, how do genetics and genomics relate to environmental science? As one example of that relationship, Karl T. Kelsey, professor in the Department of Genetics and Complex Diseases at the Harvard School of Public Health, says, “In a broad sense, it is understanding exposures.” But the tools for measuring exposure—say, to a dangerous compound or environment—still need work. Nonetheless, “genetics as an exposure tool will be a really exciting way to go,” says Kelsey. Other tools—such as microarrays and proteomic applications—also improve the measurement of exposures. “Those tools, though, are in the early days,” says Kelsey, “but that is where we are going.”
Genomics can also be used to explore the structure of communities. For example, many fish stories—real ones—teach scientists more about the interaction between genes and the environment. Douglas Crawford, professor in the division of marine biology and fisheries at the University of Miami, studies fish of the genus Fundulus, which inhabit polluted coastal waters. In fact, these fish do better in polluted than clean water. The change in environment triggers changes in gene expression and even the physiology of these fishes. By looking at these natural populations, Crawford says that scientists can learn more about polymorphoric populations, instead of the inbred ones that grabbed most of the attention in the beginning of genomics. He says, “Natural populations include more genetic variation and recombination that puts together unique gene combinations, which show the complexity of organisms responding to environmental perturbations.”
Putting Genes to Work
When asked about today’s most exciting applications of genetics and genomics, Dabney K. Johnson, senior staff scientist and leader of the mammalian genetics and genomics group at Oak Ridge National Laboratory, says, “Oak Ridge is really at the forefront as far as mice are concerned, because we are generating a population of mice that is designed to represent in model form the genetic diversity that would be characteristic of a human population.” (For more on these mice, see Science 301:456–457, 2003.) She adds, “As this population progresses, these mice will be an important environmental resource.” These mice will include 1,000 different genotypes. “You could expose these different genotypes to environmental conditions of your choice,” says Johnson
The power of genetics and genomics also attracts environmental scientists who had never used these techniques. For example, George Roderick, professor of environmental science and curator of the Essig Museum of Entomology at the University of California, Berkeley, started as an ecologist but grew interested in using genes to understand more about ecology. As it turned out, he was entering a family business. In 1986, his father—Thomas H. Roderick of the Jackson Laboratory—came up with the word “genomics” to name a new journal. The name stuck—not only for the journal but for the field, as well.
“Genomics has opened up a huge range of new loci and what they do, especially in model organisms,” says Roderick. “We have access to the adaptive nature of variation now.” He sees that ability providing new approaches to a wide range of fields, including natural history. “In bacteria,” he says, “there is excellent work showing how communities function and which genes are expressed when and how interactions occur.”
High throughput screening of single nucleotide polymorphisms, or SNPs, can also reveal more of the genetic variation. “In out-bred species, like humans,” says Crawford, “there’s likely to be more than one solution to any environmental perturbations, but they will be genotype dependent.”
Breeding Genetic Skills
Work like the Oak Ridge mouse project demands speed to create so many genomic lines. Johnson says, “High throughput genotyping is crucial.” In addition, combining these genotypes with a variety of environmental conditions will generate huge volumes of data. “The analytical techniques—bioinformatics—will also be crucial,” says Johnson, “to pull out the subtle but vital patterns and correlations from this vast swamp of data.”
Instead of just seeing how genes impact the phenotype, scientists can also explore how the environment impacts the genes. This field—called epigenetics—could teach scientists even more about the environmental influence on diseases. “One really exciting area is the effect of the environment on chromatin,” says Kelsey. “The techniques for looking at this are growing fast,” he says. They will include microarrays, microRNA, and all of the new noncoding RNAs.
Today’s students can get the tools that they need to approach environmental questions with genetics and genomics. For example, the University of California, Berkeley, offers a major in molecular environmental biology. Roderick says, “This program draws lots of students who want to do something in environmental sciences and use modern molecular skills.” He adds that these students usually know a lot about lab skills, but can lack basic background, like a general understanding of biology, evolutionary biology, and natural history.
A Consensus on Computation
Success in the future will depend on analytical skills. “Taking on this huge mass of data will require supercomputers,” Johnson says. “It is no longer a workstation kind of analysis.” Moreover, a scientist must know or develop ways to find the smallest differences. “How in the world do you find the patterns and correlations that are real and make the difference between a smoker who gets lung cancer and one who does not?” Johnson asks. “You need to find correlations between single base-pair differences in the genome and how healthy or unhealthy people have lived.” The scientists who can find those correlations will also find great jobs.
Kelsey agrees that the future will demand strong analytical skills. He mentions biostatistics and epidemiology. In addition, his students learn programming. “I believe they need that to go forward,” he says. “If you can’t program, you’ll be left behind.” The computational requirements will also continue to grow in this field. Kelsey says, “You must run the software and understand how people think about it.” In thinking about all of the computations being done and the ones that will be done soon, he pauses and then adds, “It’s a very fast-moving field. It’s extremely fun!”
For working on animals from the natural environment, Crawford recommends a knowledge of statistics and population genetics, as well as an understanding of molecular biology and how the available techniques work. The real key, he says, is finding ways to precisely and repeatedly quantify small variations. As he points out, “Michael Jordan does not jump twice as high as me, and Tiger Woods does not drive a golf ball twice as far as me, but who do you want on your team?” Although he adds that Tiger can out drive him by 100 yards, he says that small differences could mean everything. So scientists must develop accurate techniques that consistently reveal small variations in the interactions between genes and the environment.
A Growing Future
In the near future, Roderick expects the availability of loci to extend beyond model organisms and ones with relatively small genomes. “Being able to make use of that information in relevant ways will be a big field,” he says. “The ability to make use of this information is an area that is bound to grow.”
Just in case the quantitative angle of this article was not emphasized enough, remember this: “The future will be dense data,” says Kelsey. So set up a keyboard and start calculating a path to a career that unravels the environment with genetics and genomics.