Scientists Say ‘Undead’ Genes Switch On After Death


Researchers studying gene expression in mice and fish have just delivered surprising news: Some of the animals’ genes lived on after they died—and others switched on. The authors describe their findings [PDF] on the preprint server bioRxiv. 

Conventional wisdom tells us that when you’re dead, you’re dead. Sure, the microorganisms in your body may go on, but you, as an organism, are kaput. Microbiologist Peter Noble and his colleagues were operating under this basic assumption when they decided to check out the DNA of recently deceased mice and zebrafish. The researchers weren’t looking for anything in particular; rather, they were planning to test a new method they’d developed for measuring gene expression. 

Noble and his colleagues collected tissue samples from the blood and organs of newly departed fish and mice. The researchers then analyzed the animals’ DNA at regular intervals for two days (for the fish) and four days (for the mice), keeping tabs on the activity of 1063 different genes. They expected to find a gradual postmortem shutdown, and for some genes, they did. But 24 hours after death, hundreds of other genes were still kicking, and they kept on kicking right up to the four-day mark.

The story gets weirder. After death, other genes—ones that had lain dormant—actually turned on. Interestingly, most of these “undead” genes are associated with embryonic growth and development, and they typically switch off once an animal is born. At death, apparently, they switch back on. Other members of the zombie gene cohort are associated with tumor growth, a fact that Noble says might explain why people who get organ transplants from newly-dead donors are at a higher risk for cancer. 

The experiments were conducted in lab mice and fish, not people, but the researchers believe their findings have broad implications. As any true-crime podcast fan knows, current techniques for pinpointing time of death are imprecise and spotty. But Noble and his colleagues say that tracking these zombie genes could provide a far more accurate measurement, as they suggest in a second study [PDF] on bioRxiv: "The significance of this study is two-fold: selected groups of upregulated genes provide accurate prediction of postmortem time, and the successfully validated experimental design can now be used to accurately predict postmortem time in cadavers," they write. 

These studies raise all kinds of questions, both scientific and philosophical. The bottom line, Noble told Science, is that “we can probably get a lot of information about life by studying death.”

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What Do Morticians Do With the Blood They Take Out of Dead Bodies?

Zoe-Anne Barcellos:

The blood goes down the sink drain, into the sewer system.

I am not a mortician, but I work for a medical examiner/coroner. During an autopsy, most blood is drained from the decedent. This is not on purpose, but a result of gravity. Later a mortician may or may not embalm, depending on the wishes of the family.

Autopsies are done on a table that has a drain at one end; this drain is placed over a sink—a regular sink, with a garbage disposal in it. The blood and bodily fluids just drain down the table, into the sink, and down the drain. This goes into the sewer, like every other sink and toilet, and (usually) goes to a water treatment plant.

You may be thinking that this is biohazardous waste and needs to be treated differently. [If] we can’t put oil, or chemicals (like formalin) down the drains due to regulations, why is blood not treated similarly? I would assume because it is effectively handled by the water treatment plants. If it wasn’t, I am sure the regulations would be changed.

Now any items that are soiled with blood—those cannot be thrown away in the regular trash. Most clothing worn by the decedent is either retained for evidence or released with the decedent to the funeral home—even if they were bloody.

But any gauze, medical tubing, papers, etc. that have blood or bodily fluids on them must be thrown away into a biohazardous trash. These are lined with bright red trash liners, and these are placed in a specially marked box and taped closed. These boxes are stacked up in the garage until they are picked up by a specialty garbage company. I am not sure, but I am pretty sure they are incinerated.

Additionally anything sharp or pointy—like needles, scalpels, etc.—must go into a rigid “sharps” container. When they are 2/3 full we just toss these into one of the biotrash containers.

The biotrash is treated differently, as, if it went to a landfill, then the blood (and therefore the bloodborne pathogens like Hepatitis and HIV) could be exposed to people or animals. Rain could wash it into untreated water systems.

This post originally appeared on Quora. Click here to view.

Frederick M. Brown, Getty Images
Stephen Hawking’s Memorial Will Beam His Words Toward the Nearest Black Hole
Frederick M. Brown, Getty Images
Frederick M. Brown, Getty Images

An upcoming memorial for Stephen Hawking is going to be out of this world. The late physicist’s words, set to music, will be broadcast by satellite toward the nearest black hole during a June 15 service in the UK, the BBC reports.

During his lifetime, Hawking signed up to travel to space on Richard Branson’s Virgin Galactic spaceship, but he died before he ever got the chance. (He passed away in March.) Hawking’s daughter Lucy told the BBC that the memorial's musical tribute is a “beautiful and symbolic gesture that creates a link between our father's presence on this planet, his wish to go into space, and his explorations of the universe in his mind.” She described it as "a message of peace and hope, about unity and the need for us to live together in harmony on this planet."

Titled “The Stephen Hawking Tribute,” the music was written by Greek composer Vangelis, who created the scores for Blade Runner and Chariots of Fire. It will play while Hawking’s ashes are interred at Westminster Abbey, near where Isaac Newton and Charles Darwin are buried, according to Cambridge News. After the service, the piece will be beamed into space from the European Space Agency’s Cebreros Station in Spain. The target is a black hole called 1A 0620-00, “which lives in a binary system with a fairly ordinary orange dwarf star,” according to Lucy Hawking.

Hawking wasn't the first person to predict the existence of black holes (Albert Einstein's general theory of relativity accounted for them back in the early 1900s), but he spoke at length about them throughout his career and devised mathematical theorems that gave credence to their existence in the universe.

Actor Benedict Cumberbatch, a friend of the Hawking family who portrayed the late scientist in the BBC film Hawking, will speak at the service. In addition to Hawking's close friends and family, British astronaut Tim Peake and several local students with disabilities have also been invited to attend.

[h/t BBC]


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