The Effect of Environment on Genes

The Effect of Environment on Genes

Lab experiments show how sensitive genes can be to small differences in the environment

The Effect of Environment on Genes

Lab experiments show how sensitive genes can be to small differences in the environment

Many genes have consistent, powerful effects, but far more of them show a marked environmental dependency than most scientists had previously anticipated.

Many genes have consistent, powerful effects, but far more of them show a marked environmental dependency than most scientists had previously anticipated.Illustration: Getty Images

I just read a wonderfully obscure paper entitled “Factors in the Selection of Surface Disinfectants for Use in a Laboratory Animal Setting,” published in the Journal of the American Association for Laboratory Animal Science in March, by Michael Campagna and colleagues at the University of California, Los Angeles. They studied, well, disinfectants. Various kinds are used in labs, and the scientists examined, among other things, which ones have odors that lab mice find aversive. Why study that? Because it’s a small piece of a big issue related to genes and behavior: the role of the environment.

Suppose scientists want to know what a gene—let’s call it Gene Z—has to do with behavior. Using genetic-engineering wizardry, they generate a line of mice lacking Gene Z (“knockout” mice), plus another line with an extra copy of Gene Z (“transgenic overexpression” mice). Then they see if there’s something different about the behavior of either group when compared with unmanipulated control mice.

So a lab discovers that Gene Z is pertinent to, say, anxiety. Knock out the gene, and mice don’t get anxious; overexpress the gene, and they’re more prone to anxiety. (How can you measure mouse anxiety? Mice, being nocturnal, are afraid of light. Researchers might put food in the middle of a brightly lighted arena and see how long it takes for a hungry mouse to leave a comforting, shaded corner to get the food.)

With the results in, other labs get some of the Gene Z mice, eager to study different aspects of anxiety. And surprisingly often, something disquieting occurs. Another group confirms the link between Gene Z and anxiety, but they don’t see as big of an effect. Then another lab reports that the gene has no effect on anxiety. Yet another finds that Gene Z decreases anxiety.

Yikes. Everyone wonders if the scientists don’t know what they’re doing, or if the test is reliable. But research started in the 1990s by neuroscientist John Crabbe of the Oregon Health and Science University suggests a different explanation.

Genes like our fictional Gene Z, with “neurogenetic” effects on behavior, are often sensitive to small differences in the environment. Gene Z’s effects on anxiety might differ between two labs because the mice in the two are fed different kinds of food; nutrition influences brain chemistry and thus potentially Gene Z’s effects on the brain. Or maybe one of the labs uses a caustic disinfectant, or its doors bang loudly, and the mice there secrete more stress hormones, which alter the brain. Likewise with different temperatures, producing different levels of thyroid hormone.

People are often impressed with the deterministic power of genes, believing they explain everything about our biology and behavior. Many genes do indeed have consistent, powerful effects, but far more of them show a marked environmental dependency than most scientists had previously anticipated. Thus, what Dr. Crabbe and others show is that in many cases, you can’t really say what a gene generically “does”—so perhaps be a bit skeptical about such pronouncements. Instead, you can only safely say what a gene does in the environment(s) in which it has been studied.

This is pertinent to mice living in different laboratories. But just imagine how much that would apply to a species that can live in dramatically different environments—in deserts, tundra and rain forests, in hunter-gatherer bands and in dense cities, in close-knit communities or as hermits. There is no species that matches humans in the range of ecosystems, habitats and social system in which it lives. And that suggests there is no species freer from the power of genes than humans.

By Robert M. Sapolsky

Aug. 11, 2016 2:08 p.m. ET

wsj

The Effect of Environment on Genes

The beautiful satellite images of algae blooms that are helping to save our water

The beautiful satellite images of algae blooms that are helping to save our water

Lakes and coastlines usually wear the tint of sapphire, but sometimes these waters turn into huge bowls of muddy pea soup, when harmful algae invade. Thanks to climate change, it’s happening more often than ever before, all over the world: from Greenland to the Rio Olympic diving pool just yesterday.

Looking from satellites orbiting the earth though, landscapes plagued by algae are disguised as beautiful paintings of swirling turquoise—but scientists can use these lovely images to predict the blooms and help people avoid the dangerous green scum.
An algae bloom occurs when a population of algae in the water grows exceptionally fast, fueled by fresh nutrients brought to the area or by warming temperature. As a natural part of the marine ecosystem, most types of algae are not toxic. But some are. The blooms that release toxins are officially termed Harmful Algae Blooms (HAB), and are a serious health hazard to animals and human beings. Some of the most common HABs are blue-green algae (or cyanobacteria) blooms that happen in fresh water, and phytoplankton blooms in the oceans. The toxins these blooms release can cause paralysis in animals and more rarely in human beings, contaminate water supplies and seafood, and suffocate masses of marine life when they deplete oxygen in water as they decompose.
These harmful blooms are more likely to occur in areas with relatively still water, or at the mouth of a river and coastal areas, where waste full of nitrogen and phosphorous—fresh nutrients algae love to feast on—pour into the ocean.
Lake Erie algae bloom 2016 June
An algae bloom smaller than previous years was seen this summer in Lake Erie, Ohio, on June 12, 2016.(NASA)

There are some parts of the world that suffer annual massive algae blooms. In Lake Erie in Ohio, United States, a bloom caused a tap water ban in nearby towns in 2014; the next year, a bloom hit the coast of Qingdao in China (though beachgoers there were strangely excited about frolicking in thick green sludge than worrying about the potential health effects). It’s likely to become a more common occurrence: a 2015 study by NASA and the US National Oceanic and Atmospheric Administration (NOAA) warns that because algae grows faster in warmer temperatures, blooms may go up by 20% in the next century because of global warming.

Because there is no quick fix to this environmental hazard, Richard Stumpf, an oceanographer from the NOAA is partnering with NASA to use satellite remote sensing technology to at least monitor the blooms. The project has created a HAB forecast system tracking blooms in western Lake Erie and Florida. The forecast releases weekly bulletinswith information on how much algae there is during a current bloom, where the bloom is at a given time (they can move around) and how concentrated it will be. The bulletins help boats avoid getting trapped in areas with thick scum and inform government agencies how to appropriately apply treatment to water supply sources.
Lake Erie colorized algae bloom HAB forecast
Lake Erie, Ohio, shown in natural color (above), and in a colorized map (below). Dark red indicates areas with most concentrated algae, blue indicates the least concentrated. Black indicates areas where algae has not been detected.(European Space Agency and National Oceanic and Atmospheric Administration)

Instead of making use of true-color satellite images like those below, the forecast system uses algorithms to create colorized heat maps that show the amount of biomass of the bloom. Stumpf says the colorized images help make sense of areas that are especially impacted by algae, like Lake Apopka, Florida, where the water has turned so green that it becomes indistinguishable from land.

Sea of Marmara algae bloom 2015 may
A bloom in the Sea of Marmara, an inland sea in Turkey, south west to the Black Sea on May 17, 2015.(NASA)
A bloom in Barents sea, an algae hotspot on the edge of the Arctic and off the northern Norwegian coast was seen on July 6, 2016.(NASA)
Bay of Biscay algae bloom 2013 May
Phytoplankton blooms in the Bay of Biscay, off the western coast of France, on April 20, 2013.(NASA)
Lake Saint Clair algae bloom
Lake Saint Clair in Michigan, experienced a bloom on July 28, 2015.(NASA)
Falkland Islands algae bloom 2016 December
An algae bloom near Falkland Islands, off the coast of southern Argentina on December 2, 2015.(NASA)
Antartica Ross Sea algae bloom 2011 January
Phytoplankton thrive in the Ross Sea, Antartica, when the southern summer provides them with 24-hour day light, on January 22, 2011.(NASA)
Bering sea algae bloom 2014 september
A recurrent phytoplankton bloom in Bering Sea, Alaska on September 4, 2014.(NASA)

The beautiful satellite images of algae blooms that are helping to save our water

A Price Tag on Carbon as a Climate Rescue Plan

California’s program is the latest incarnation of an increasingly popular — and much debated — mechanism that has emerged as one of the primary weapons against global warming. From China to Norway, Kazakhstan to the Northeastern United States, governments are requiring industries to buy permits allowing them to emit set levels of greenhouse gases. Under these plans, the allowable levels of pollution are steadily reduced and the cost of permits rises, creating an economic incentive for companies to cut emissions.

The system encourages companies to find the least expensive ways to make the cuts, either by adopting cleaner energy technology or by investing in outside emission-control projects.

A Price Tag on Carbon as a Climate Rescue Plan

A new green wave

A few pioneering businesses are developing “sustainability policies” worthy of the name.

A new green wave

10 High-Tech, Green City Solutions for Beating the Heat

10 High-Tech, Green City Solutions for Beating the Heat

10 High-Tech, Green City Solutions for Beating the Heat

10 High-Tech, Green City Solutions for Beating the Heat

10 High-Tech, Green City Solutions for Beating the Heat

10 High-Tech, Green City Solutions for Beating the Heat

The value of vegetation in urban areas goes beyond cooling and shade. City plantings can also help improve air and water quality through filtering mechanisms.

Pictures: 10 High-Tech, Green City Solutions for Beating the Heat.

 

6 Easy Ways Small Businesses Can Help Save The Planet

Going green isn’t just good for the environment; it can help your small business improve its bottom line and gain a competitive advantage over larger chains.

6 Easy Ways Small Businesses Can Help Save The Planet.

 

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