Experts have discovered the first mutation in the development of human evolution.

Pixabay

For the first time, scientists have caught a glimpse of the earliest genetic mutations in human development.

Using whole genome sequencing, they wound back time on cell samples from adults and revealed what took place in the genome when they were still microscopic embryos. It turns out, our first two cells contribute to our development in very different ways.

Biology Reference

Mutations come in two forms: the hereditary ones we get from our parents, which can be found in virtually every cell of the body; and the acquired (or somatic) mutations that can occur at any stage of a person's life, including those very first days when the embryo is just starting to split into multiple cells.

Somatic mutations don't necessarily cause problems, but they can sometimes lead to cancer and other diseases. They also don't necessarily live in every cell (that's called mosaicism). 

We have a fairly murky understanding of the somatic mutations that happen during the earliest life stages, because we can't just watch that stuff happening in real time.

But now researchers have discovered a way to trace these mutations back to their first appearance.

Medical Xpress

"This is the first time that anyone has seen where mutations arise in the very early human development. It is like finding a needle in a haystack," says geneticist Young Seok Ju from the Wellcome Trust Sanger Institute in the UK and the Korea Advanced Institute of Science and Technology.


"There are just a handful of these mutations, compared with millions of inherited genetic variations, and finding them allowed us to track what happened during embryogenesis."

To find these mutations, the team analysed blood and tissue samples from 279 people with breast cancer. Using samples from cancer patients allowed them to test whether mutations were present in both normal blood and tissue, and in surgically removed tumour samples.

Since breast cancer tumours develop from a single cell, a somatic mutation would either be present in every tumour cell, or not at all, which gives a clue to its possible origins.

By tracking and comparing the spread of different mutations in these various tissue samples, the scientists verified a whopping 163 mutations that must have happened within the first few cell divisions of the persons' embryonic development.

University of South Florida

This gave them a unique insight into how early embryonic cells interact.

And that's not all - a statistical analysis revealed that when a fertilised egg divides for the first time, those two cells actually contribute building material for the rest of the body at different proportions.

It appears that one of the first two cells that make us up gives rise to 70 percent of the body tissue, while the other one chips in for the rest.

"We determined the relative contribution of the first embryonic cells to the adult blood cell pool and found one dominant cell - that led to 70 percent of the blood cells - and one minor cell," says molecular biologist Inigo Martincorena from the Sanger Institute.

indiatoday.intoday.in

"This opens an unprecedented window into the earliest stages of human development."

That's exciting, because having that window will let us discover even more about how humans develop and acquire various mutations from the get-go.

Even though the vast majority of mutations are random and harmless, occasionally they can affect an important gene, causing a developmental disorder or a disease.

"Essentially, the mutations are archaeological traces of embryonic development left in our adult tissues, so if we can find and interpret them, we can understand human embryology better," says lead researcher Mike Stratton, director of the Wellcome Trust Sanger Institute.

The researchers hope their discovery is just the first of many steps that will help us gain a better understanding of what happens to humans in the earliest days, when we're all nothing more than just a clump of cells.

Other articles on the same theme:

• The genes of extinct species, unidentified, were found in Melanesian DNA, ( NATURAL BLACK BLONDES ) the population is located in the South Pacific

• DNA from the human embryo has been modified by a Swedish researcher

• Researchers have created anti-aging guide

• Top 10 extinct species that will be recreated a genetic

Story source: 

 

The above post is reprinted from materials provided by Sciencealert . Note: Materials may be edited for content and length.

The genes of extinct species, unidentified, were found in Melanesian DNA, ( NATURAL BLACK BLONDES ) the population is located in the South Pacific

Melanesian Unic People photo: Pinterest

The genes of extinct species, unidentified, were found in Melanesian DNA, the population is located in the South Pacific.

According to new research, this species did not belong to Neanderthal or denisovan, but could represent a third species, unidentified so far.

Ryan BOHLENDER, a geneticist at the University of Texas, said that "perhaps I have missed a species or omitted links between species." He and his team tried to find out the percentage of DNA specific hominids that people today still do have and the result was represented by discrepancies revealing that the pairing of our ancestors with Neanderthal and Denisovan there is In fact, the primary explanation. It is believed that, far from 10,000 years to 60,000 years ago, they migrated from Africa and had contacts with populations living in Eurasia and these contacts have left a footprint specified in our DNA that lasts until today, Europeans and Asians having choices Neanderthal genetic distinct.


Moreover, researchers discovered earlier this year that Europeans have inherited from Neanderthal genes that put them at the disposition emergence of diseases and increased risk of depression. The percentage of DNA that Europeans and Asians have inherited from them is 2.8%.


But when it comes to DNA inherited from denisovan, things get a bit more complicated, especially if the population of Melanesia, an area in the South Pacific that includes Vanuatu, Solomon Islands, Fiji, Papua New Guinea, New Caledonia, Papua Western and Maluku Islands. One of the researchers involved in the project said: "Europeans show no gene denisovan and population in China only a very small percentage, 0.1%. However, if Melanesian this percentage is 1.11%." After these investigations, those who started the study concluded that the three species would have much to do with the current population of the Melanesian.

Melanesian People photo: Pinterest

Interaction with other species prehistoric ancestors may have been more complex than we had expected and even if there were no findings that show the existence of other species, that does not mean they did not exist.




Other articles on the same theme:

• DNA from the human embryo has been modified by a Swedish researcher
• The most mysterious eight tribes in the world
• Amazons of Dahomey - the most feared Women in History
• The oldest civilization existing today. They were the first explorers who dared to cross the ocean 58,000 years ago

Story source:


The above post is reprinted from materials provided by Science Alert . Note: Materials may be edited for content and length.

Woolly mammoth will be cloned using leftover tissue

Scientists have a fix for one of the greatest threats facing our climate. It’s big, it’s hairy, and it’s been dead 10,000 years. In a madcap scheme to slow the melt of arctic permafrost, researchers are trying to resurrect the woolly mammoth.


How to Grow a Mammoth

Mammoth de-extinction sounds like complicated business, but there are actually only two ways to do it:



Clone a mammoth using leftover tissue.

Rejigger the genetic profile of the mammoth’s closest living relative, the Asian elephant, by inserting bits of mammoth DNA.Researchers have made some progress on the first approach. In 2013, Russian scientists found viable tissue among the bony remains of a woolly mammoth they named “Buttercup.” Researchers are now trying to collect DNA from Buttercup’s well-preserved marrow cells. If all goes well, they will sneak her genetic blueprint into the egg of an elephant. The resulting embryo will be a Buttercup clone.

So far, scientists have yet to recover a complete mammoth genome. But that’s just the first challenge. Creating a viable embryo and bringing it to term is another problem entirely. Previous attempts at cloning have fared poorly. Scientists tried cloning the recently extinct ibex in 2003. They brought a baby Ibex to term, but the creature survived fewer than 10 minutes owing to a defective third lung.

The second approach to mammoth resurrection offers more promise. Scientists just need to make a few small adjustments to an elephant’s DNA. The new species would be less mammoth and more a mammoth-elephant hybrid — a winter-proofed pachyderm armed for life in the frigid north.

Because the mammoth is one of the better-preserved bygone species, it’s a prime candidate for the first successful de-extinction. Scientists sequenced the mammoth genome in 2008, and researchers have since catalogued the slim set of genetic variants separating mammoths from elephants — cold-weather upgrades like more hair, more fat and a higher tolerance for sub-zero temperatures.

Last year, Harvard geneticist George Church and his colleagues successfully spliced mammoth genes into the cell of an Asian elephant. Church says de-extinction could be just a couple of years away. In the meantime, scientists are left to speculate on the climate-saving potential of this prehistoric beast.

The Permafrost Problem
 

Climate change has several soft deadlines — tipping points at which human-caused warming could set off natural feedback loops that would make the planet dramatically hotter. Drought could decimate forests, causing trees to bleed their stores of carbon. Rising temperatures could also melt Arctic permafrost.

This is among the sobering consequences of planetary warming. Once permafrost has thawed, microbes will devour the organic matter in the soil underneath — the leftovers of prehistoric plants. Metabolizing microbes would exhale gobs of methane, a powerful greenhouse gas.
Methane has less staying power than carbon dioxide — it lingers in the atmosphere for decades as opposed to centuries — but it traps 80 times as much heat over a 20-year period. Methane from permafrost could produce up to 0.5º C of additional warming by 2100. Earth has already seen 1º C of warming over the last century. And just 1.5º of warming could trigger the melt of Arctic permafrost.

Here’s where mammoths come in.

A Mammoth-Sized Solution


Herds of mammoths once ruled the Arctic. They nurtured grasslands and suppressed the growth of forests. After mammoths departed, grasslands turned into forests and tundra, where we now find all that permafrost.

Paradoxically, permafrost has an insulating effect, keeping the soil underneath warm relative to winter temperatures. Mammoths could dig through snow to find grass hiding beneath. After chomping down, they would leave manure behind, nurturing the growth of more grass.
Russian scientists have set up a reserve in Siberia for wild horses, ox and bison in an effort to recreate an Ice Age ecosystem. They found that during the winter, when it was -40º C outside, the ground that was covered in snow remained a balmy -5º C. Where animals had trampled down the snow, the ground was -30º C. Mammoths could be the heavy arsenal needed to avert the release of methane

“In conservation biology it’s called a reintroduction


As wolves were reintroduced to Yellowstone, beavers to Sweden, etc. They’re disruptive, but they’re supposed to be,” said Stewart Brand, author and co-founder of Revive and Restore, a project to bring back the woolly mammoth. “As keystone species and ecological engineers, they move the whole ecosystem toward greater bio-abundance and biodiversity.”

Brand said the subarctic was once the Serengeti of the north, home to a rich diversity of animals — musk ox, bison, Yakutian horses, woolly rhinocerous, cave lions and cave bears. He believes mammoths would improve the landscape and that they could endure global warming.

Woolly mammoths survived many warming periods between the glacial ice ages,” said Brand. “There are also non-woolly mammoths such as the Columbian mammoth that inhabited much of North America. They also could return. The ecology of our continent misses the various elephants and would welcome them back.”

De-extinction offers mammoths a chance for redemption. It was climate change that drove the species to the brink of extinction. The end of the last ice age shrunk their habitat, and humans dealt the final blow by hunting them until none remained.

If fulfilled, these dreams of species revival could see mammoths come back from the dead to cool the planet, returning from extinction to save us from ourselves.


Other articles on the same theme:

• DNA from the human embryo has been modified by a Swedish researcher

• Top 10 extinct species that will be recreated a genetic

• The mystery of the famous '' Alien '' Atacama continues in 2016

• Giant Ape Lived Alongside Humans !

• These trees in Ecuador "Walking Palms" move over distances up to 20 meters per year. How is this possible?

The above post is reprinted from materials provided by  POPSCI . Note: Materials may be edited for content and length.