genetic manipulations - Lynette M. Burrows

Mixing Holiday Traditions With Science

Putting up the Christmas tree is one of my beloved holiday traditions. For many years, I went to a tree farm a couple of weeks before Christmas. We’d cut down a tree, bring it home, and decorate it. I wasn’t mixing holiday traditions with science back then. But the science of Christmas trees is fascinating.

The Traditions

The Romans decorated their temples with fir trees for the festival of Saturnalia. Christians used fir trees as a sign of everlasting life with God. Many people credit the Germans with bringing the Christmas tree into their homes.

Records show that Martin Luther, a 16^th century preacher, was one of the first to bring a Christmas tree into his house and put lights on it.

Read more about the first Christmas trees.

Oh Christmas Tree

image of a pine tree branch with a pine cone frosted with snow

When shopping for a Christmas tree, we want the right shape, the right height, and color. We want the tree to hold on to its needles as long as possible. And we want the tree to look fresh for weeks. These are the traits Christmas tree growers want to foster in their trees.

Fraser and noble firs are the most popular species for Christmas trees. Christmas trees are grown on tree farms in all 50 states and in Canada. Oregon is the number one state in the US for harvested trees. North Carolina is second and Michigan is third.

It can take 5-15 years for a fir to grow to 6-7 feet tall. Not only does it take years to grow, the grower must remove all pine cones by hand. And each tree can grow hundreds of pine cones. The grower also must be wary of root rot.

Applying Science to Christmas Trees

Image of branches of a green fir tree--are we improving the planet when we are mixing holiday traditions with science?

Scientists are helping Christmas tree growers create a better Christmas tree. They want to improve the growth rate and durability of the trees. And they want trees that are resistant to root rot.

Root rot is caused by the water-mold genus Phytophthora, a tree stricken with it can die in a matter of days./ And once the fungus is in the soil, it’s impossible to get rid of.

The Scientists

Bert Cregg

Cregg is a forest researcher at Michigan State University and a renowned expert on Christmas tree production. Wired reported on his work to reduce coning in Christmas Trees using growth regulators. His method works but is not yet a financially feasible technique.

John Frampton

Frampton is a professor in the department of Forestry and Environmental Resources at North Carolina State University. He is an expert on Fraser firs. Frampton is helping growers fight root rot.

He tested 32 of the world’s 50-odd true fir species and found a Japanese tree called the Momi fir strongly resists phytophthora invasion. The Momi fir is not a Christmas tree, so Frampton helps growers make chimeric trees. He shows them how to graft seedling Fraser firs to Momi seedling roots. It works, but it’s a time-consuming process.

“We are doing DNA sequencing to understand the DNA of Christmas trees, and in the long term, this may lead in the future to genetic engineering,” Frampton said. “But there is still more knowledge and techniques we need to develop before we’re to the point that agriculture is now.”
John Frampton as quoted on PopSci.com

Dr. Rajasekaran Lada

Dr. Lada, a professor and founding director of the Christmas Tree Research Center at the Nova Scotia Agricultural College in Truro, is working with the hormone (ethylene). It is the hormone that triggers the tree to release its needles.

He discussed two methods to slow or prevent needle release on a December 2010 episode of Science Friday In that episode; he revealed that his team discovered that trees that drink the most water after you bring them home, lose their needles the fastest. His team also discovered that the types of lights we string on the trees also affect how long the tree keeps its needles. (Hint: using white spectrum lights are best.)

Mixing Holiday Traditions with Science

Science fascinates me. But sometimes scientists take things too far. Genetic manipulation of food animals, of animals facing extinction, and of plant foods are all being attempted.

Reactions to science also fascinates me. My reaction is mixed. I think creating better Christmas trees is good for survival of the trees. And I fear that commercial desires drive the science and worry about future consequences. Are we improving the planet when we are mixing holiday traditions with science? I don’t know? What do you think?

Does the DNA sequencing, experiments, and possible future genetic manipulation of and on Christmas trees bother you? Is it the idea of mixing holiday traditions with science that is most disturbing? Messing with nature? Or are you okay with genetic manipulation of plants we don’t eat? Should we be mixing holiday traditions with science?

A Team of Awesome Women & the Nobel Prize

Strong women come in all sizes, colors, religions, and abilities. Today we celebrate two women who discovered one of the greatest breakthroughs in the biological sciences. Dr. Emmanuelle Charpentier and Dr. Jennifer A. Doudna were awarded the 2020 Nobel Prize for Chemistry this week for their development of a groundbreaking method for editing DNA. They discovered the genetic scissors called CRISPR/Cas9. It’s a tool that allows scientists to “snip” the DNA of organisms, “allowing for easy and precise genetic modifications.” They are the sixth and seventh women in history to win the Nobel Prize in Chemistry and the first pair of women to win the chemistry prize. This team of awesome women teamed up for a common goal, and the results are world changing.

Image of the Nobel Prize Museum in Stockholm, where photos of this Team of Awesome Women will appear — The Nobel Prize Museum, Stockholm, by Liridon, CC BY-SA 4.0 via Wikimedia Commons

Excellence is never an accident. It is always the result of high intention, sincere effort, and intelligent execution; it represents the wise choice of many alternatives—choice, not chance, and determines your destiny.
Aristotle (384-322 BC)

Dr. Emmanuelle Charpentier

Emmanuelle Charpentier was born on December 11, 1968 in Juvisy-sur-Orge, a commune in northern France, 18km south-east of Paris.

Charpentier studied biochemistry, microbiology and genetics at the Pierre and Marie Curie University. She received a research doctorate from the Institut Pasteur in 1995. She moved to the United States in 1997.

As a postdoctoral fellow at New York’s Rockefeller University, she helped show how Streptococcus pneumoniae develop vancomycin resistance. (Read more about S pneumonia a leading cause of bacterial pneumonia and meningitis and other infections in the United States.)

Charpentier also worked at the St. Jude Children’s Research Hospital and at the Skirball Institute of Biomolecular Medicine during her five-year stay in the U.S.

In 2002 her work took her to Vienna, then to Sweden, and to the Max Planck Institute for Infection Biology in Berlin.

Charpentier approached Jennifer Doudna at a research conference in 2011. And a team of awesome women formed.

Dr. Jennifer Doudna

Jennifer Doudna was born in Washington, D.C. in 1964. She moved to Hawaii when she was seven years old. There, her educator parents encouraged her love of the biological sciences.

She received her Bachelor of Arts degree in Biochemistry and earned a Ph.D. in Biological Chemistry and Molecular Pharmacology from Harvard Medical School in 1989.

From early in her career, Doudna studied RNA. At Yale in her group crystallized and solved the three-dimensional structure of the catalytic RNA. Her experiments with high powered x-ray diffraction at Berkley gained her further recognition.

The list of awards and honors she has received is long.

In 2011, she met Charpentier at a research conference. After that, she cancelled all her other obligations to focus on researching CRISPR.

CRISPR

Both Doudna and Charpentier studied Streptococcus pyogenes bacteria. Also known as Strep A, the DNA of this bacteria has segments that repeat.

Other scientists had discovered fragments of genetic material from viruses attacking Strep A between the bacteria’s repeating DNA segments. They named these fragments ‘clustered regularly interspaced short palindromic repeats’ or CRISPR. CRISPR prevented those viruses from attacking the Strep A for a second time. But nobody was sure how the bacteria’s immune response worked.

Charpentier and her team discovered that the bacteria made a previously unknown form of RNA that recognized the genes of viruses if they attempted to attack the bacteria again.

Charpentier needed to collaborate with an expert on RNA. Doudna was her choice.

Two Awesome Women Team Up

They discovered that Strep A used an enzyme called Cas9 to slice up viral genetic material and incorporate it into its own DNA. They wondered if they could create a piece of RNA to target a specific point on any gene, not just a viral one.

In one year’s time, they successfully created a modified RNA segment. They called this segment CRISPR RNA. This segment “known as CRISPR RNA or crRNA, that guides the segment to the right place and then uses Cas9 to snip out a piece of DNA with extreme precision, in some cases as small as a single genetic letter.”

The Impact

Scientists around the world already use their discovery. Scientists are using CRISPR/Cas9 to develop cancer-fighting drugs, to create crops that can better withstand drought, to treat genetic diseases, and in many other applications. You may remember the article, Hope of a Cure for Sickle Cell, posted on this blog in July.

Typically, acceptance and common usage of breakthrough scientific discoveries takes a decade or more. And it’s at least a decade, often longer, before the discovering scientists get considered for a Nobel Prize.

This technology has utterly transformed the way we do research in basic science,” asserts Dr. Francis Collins, director of the National Institutes of Health. “I am thrilled to see Crispr-Cas getting the recognition we have all been waiting for and seeing two women being recognized as Nobel Laureates.”

Ethical Questions

Both Doudna and Charpentier are aware of the potential for ethical issues related to their discovery.

In 2019, Chinese scientist He Jiankui said he had used CRISPR on two human embryos. His announcement caused a raging scientific scandal.

Doudna’s recent book A Crack in Creation: Gene Editing and the Unthinkable Power to Control Evolution, explores the ethic issues related to CRISPR. She cautions, “we as a community need to make sure we recognize we are taking charge of a very powerful technology.”

Congratulations and Cautions

In eight short years, Doudna’s and Charpentier’s discovery has changed scientific research. The world is teetering on the edge of breakthrough treatments and cures for many diseases. Their shared Nobel Prize is extraordinary and well deserved.

But their discovery also has the world balanced on the edge of a slippery slope. Genetically altered embryos to cure disease could end up with genetically designer babies. How far will we go? Many science fiction books explore what might happen when we can alter the genes of animals and humans. In my Fellowship Dystopia series, primitive genetic manipulation creates an army of assassins and a war.

So far, scientists are self-regulating. Will we someday need a global board for ethical review? And how some misuse that power?

These two awesome women teamed up for a common goal, and the results are world changing. Who knows what the next team of women will achieve. Anything is possible.

Should You Worry About Saboteur Genetics?

Most of us are familiar with the discomfort of a mosquito bite. And unfortunately, many of us have acquired a disease from a mosquito bite. In January 2021, the eggs of more than 750 million genetically modified male mosquitoes will be released in the Florida Keys. Their modifications create a form of genetic sabotage. Should you worry about saboteur genetics?

In today’s article, we’ll discuss the mosquito, the diseases carried by this species of mosquito, and what we know about this test.

The Mosquito

Life Cycle

There are 3,500-4,000 species of mosquitoes. Their life cycle from birth to larva takes from five to forty days, depending upon ambient temperatures, density of larval population, and food supply.

Most mosquito lay their eggs on the surface of stagnant water. Clutches of eggs of hatch as soon as possible, and all the eggs in the clutch hatch into larvae at much the same time.

As larvae, they are mobile and feed on algae and organic material. Larvae develop through four stages, then they metamorphose into pupae.

Pupae typically hang from the surface of the water by their respiratory trumpets. Depending on temperature and other circumstances, in a few days the adult mosquito emerges.

Adult Mosquitoes

Within a few days, the adult mosquito mates. In most species, the males form large swarms around dusk, and the females fly into the swarms to mate.

The males live about five to seven days. The females live up to a month.

Both male and female mosquitoes feed on nectar, aphid honeydew, and plant juices. In many species, the females’ mouthparts can pierce the skin of animals. They feed on blood from vertebrates, (mammals, birds, reptiles, amphibians, and some fish. Some invertebrates, primarily other arthropods). The blood contains protein and iron needed to produce eggs.

Blood-sucking mosquitoes inject saliva into their victims. Their saliva acts like an anticoagulant; without it, the female mosquito’s proboscis might become clogged with blood clots. The saliva also is the principal route by which mosquito transfers pathogens into the bodies of their blood source.

And that is the crux of the matter.

Mosquito-carried Diseases

Mosquitos can carry viruses, bacterial disease, and parasites. They remain unaffected by the disease and transfer it to their human (or animal) host via their saliva.

Malaria is a parasitic disease. You probably already knew mosquitoes carried it. But it’s not a disease the Florida officials are trying to reduce or eradicate.

Diseases you may have heard of include the Zika virus, yellow fever, dengue fever, and West Nile fever. There are many more, but these are the primary diseases that concern the officials in Florida. In 2009 and 2010, the Florida keys suffered outbreaks of dengue fever.

The Florida Keys attempts to control the mosquito population with aerial, truck, and backpack spraying larvicides and pesticides at a cost of more than a million dollars per year. Their efforts are not effective.

Saboteur Genetics

It has taken almost a decade to get seven state agencies and the EPA to approve the experiment that will begin in January 2021.

Oxitec is the US owned, British-based company that developed the genetically modified organism (GMO). They altered the male mosquito’s genetics to produce female larvae that die. Thus the females never get to adult stage where they would bite anyone.

According to Oxitec, they tested this GMO mosquito in the Cayman Islands, Panama, and Brazil. They report that release of their GMO male reduced this species of mosquito by 95% in an urban area of Brazil.

Oxitec will release over 750 million male eggs over a two-year period. The FDA requires Oxitec to notify Florida state officials 72 hours before releasing the mosquitoes. They also must conduct ongoing tests for at least 10 weeks after release.

Oxitec also plans to release this GMO mosquito in Harris County, Texas, in 2021.

Environmental & Human Risk

Oxitec states they have released billions of the GMO mosquitos. “There is no potential for risk to the environment or humans.” But some fear there will be an impact to local birds, fish, and insects who feed on mosquitoes.

Others are angry that Florida Keys officials are spending money on these GMO mosquitoes during the pandemic, economic hardships, and racial tensions. They feel spending the money on those issues would be better.

Worry About Saboteur Genetics?

It’s hard to know. The EPA declined to run its own safety tests on this GMO. Oxitec says they have plenty of evidence of their claim that there is no risk. I tend to not trust self-reporting and self-regulation by a private corporation. On the other hand, wiping out these awful disease would be a very good thing. Does the good outweigh the risk? Florida Keys officials think so.

These mosquitos are not the first GMO insect released in the United States. The first GMO insects released in the US, also from Oxitec, were early versions of pink bollworm moths. The program intended to wipe out this cotton pets in the U. S Southwest. The GMO insect only had a genetic marker. This modification only identified it. It did not alter its fertility or lifespan.

In this transcript from NPR’s All Things Considered, Ari Shapiro speaks with Nora Besansky, a professor of biology specializing in mosquitoes, about what would happen if mosquitoes were eradicated.

Are you worried? Is your worry based on your risk-aversion? Or perhaps it’s based on a lack of control? Or perhaps, you fear we are on the verge of our own version of Jurassic Park like in my post conservation genetics. Let me know in the comments. Should you worry about saboteur genetics?

The Good, the Bad, and the Ugly

Conservation Genetics is in the good, the bad, and the ugly spotlight. Conservation Genetics “aims to understand the dynamics of genes in populations principally to avoid extinction.” Clear as mud?

Illustration of a strand of DNA--The good, the bad, the ugly of Conservation Genetics

An Example

It may be easier to understand with an example. Conservation genetics aims to help endangered species, like African cheetahs. Today the existing 10,000 African cheetahs share 99 percent of their DNA. In other words, they’re all related. This means there is little genetic diversity. Low genetic diversity leads to a population that is highly susceptible to disease. Disease that could make the African cheetahs extinct.

Photo of the African cheetah. The Good, the Bad, and the Ugly about Conservation genetics and saving the African cheetah.

Scientists involved with cheetah breeding projects determine how closely related two cheetahs are. They want to reintroduce genetic variety into the population of cheetahs. So, they choose the ones that are the furthest apart genetically and breed those two together.

If they are successful, the cheetah population will grow. (Source: https://www.scientificamerican.com/article/better-living-through-conservation-genetics/)

Revive & Restore

Revive and Restore is a nonprofit organization. Its mission is to “enhance biodiversity through new techniques of genetic rescue for endangered and extinct species.” One of their funded projects searches for the genomic trigger of bleaching the coral reefs. They say that this study has the “potential opportunity to engineer genomic resilience to climate change. They also hope to de-extinct the Woolly Mammoth.

The Good

Preserving some species (bees?) would be good, even essential, for the survival of the human race. And who would argue against restoring beautiful cats like cheetahs? Or the coral reefs that protect shorelines and provide habitats for many species?

The Bad: Not a Simple Answer

According to Nature, the early studies of the low genetic variability of the cheetah had many inconsistencies. But those studies brought genetics into conservation efforts and research. Conservationists are learning. They study population decline and inbreeding many near-extinction species.

The cheetahs are one of many species that have developed low genetic variety despite no evidence of population decline. The authors of the article in Nature caution that scientists may study and manipulate genetic variations that do not matter to the species.

They suggest that for some species, the low genetic variations during a population decline may be the best genetic survival mechanism for the species.

The Ugly: Consequences

Conservation genetics is a young discipline. Young enough that they do not know what, beyond selective breeding programs, they might be able to do.

Even with selective breeding programs, there have been consequences. “when a population of Tatra mountain ibex in Czechoslovakia was ‘enriched’ by new animals from Sinai and Turkey, the offspring inherited an inappropriate calving date, giving birth in mid-winter.” The calves born in the winter died.

Learning how to de-extinct the Woolly Mammoth may help its current day cousins survive longer. We don’t know what the consequences of de-extincting any species would be. We rarely know the consequences of any new scientific research will be. Does that mean we should abandon new research?

Ethics

As usual, the ethics discussions lag the scientific discussions and studies. Are conservation genetic efforts “directing evolutionary change?” Is de-extinction of long-gone species, like the Woolly Mammoth, an ethical thing to do? What about saving the coral reef? Or the cheetahs?

We humans are responsible directly and indirectly for the extinction of many species. Does that mean we have a moral duty to restore the species? If that is our moral duty, what about our duty to our species? If we learn enough, we could eradicate some diseases. Should we? Is there a line we should not cross?

What do You Think?

We merely touched on the good, the bad, and the ugly of Conservation Genetics. Had you heard of conservation genetics before? Will the potential good of conservation genetics outweigh any bad or ugly consequences? Would you de-exterminate the Woolly Mammoth, if you could?

If this post made you think,, you might like to read “Head Transplants.”