Jibarosoy + genetics   18

How the Western Diet Has Derailed Our Evolution - Nautilus - Pocket
Years ago, impelled in part by their oldest daughter’s constipation problems, the Sonnenburg family revamped its diet. They threw out all processed food-stuffs, and began eating plenty of veggies and whole grains. They bought a dog. Justin Sonnenburg began hand-milling his own wheat berries for bread. He took up gardening. And when he compared his archived microbes from years ago with recent ones, he discovered that his microbial diversity had increased by half. “That’s a huge difference,” he told me, “as big as the difference between Americans and Amerindians.”

It remains to be seen what detailed analysis will reveal about this diversification—how many came from his dog, from soil, from the sourdough he handles; how many might have been there all along in depressed numbers, and bloomed on a fiber-rich diet. What it showed the Sonnenburgs, however, was that without fully understanding how the microbiome works, you can still push it in a healthier direction.
Health  biology  Genetics  Food  Personal 
may 2019 by Jibarosoy
The History of African Gene Flow into Southern Europeans, Levantines, and Jews
Previous genetic studies have suggested a history of sub-Saharan African gene flow into some West Eurasian populations after the initial dispersal out of Africa that occurred at least 45,000 years ago. However, there has been no accurate characterization of the proportion of mixture, or of its date. We analyze genome-wide polymorphism data from about 40 West Eurasian groups to show that almost all Southern Europeans have inherited 1%–3% African ancestry with an average mixture date of around 55 generations ago, consistent with North African gene flow at the end of the Roman Empire and subsequent Arab migrations. Levantine groups harbor 4%–15% African ancestry with an average mixture date of about 32 generations ago, consistent with close political, economic, and cultural links with Egypt in the late middle ages. We also detect 3%–5% sub-Saharan African ancestry in all eight of the diverse Jewish populations that we analyzed. For the Jewish admixture, we obtain an average estimated date of about 72 generations. This may reflect descent of these groups from a common ancestral population that already had some African ancestry prior to the Jewish Diasporas.

Author Summary

Southern Europeans and Middle Eastern populations are known to have inherited a small percentage of their genetic material from recent sub-Saharan African migrations, but there has been no estimate of the exact proportion of this gene flow, or of its date. Here, we apply genomic methods to show that the proportion of African ancestry in many Southern European groups is 1%–3%, in Middle Eastern groups is 4%–15%, and in Jewish groups is 3%–5%. To estimate the dates when the mixture occurred, we develop a novel method that estimates the size of chromosomal segments of distinct ancestry in individuals of mixed ancestry. We verify using computer simulations that the method produces useful estimates of population mixture dates up to 300 generations in the past. By applying the method to West Eurasians, we show that the dates in Southern Europeans are consistent with events during the Roman Empire and subsequent Arab migrations. The dates in the Jewish groups are older, consistent with events in classical or biblical times that may have occurred in the shared history of Jewish populations.
Race  Genetics  Latinos_+_TW  racism  Power_in_America 
october 2018 by Jibarosoy
Cracks in the code: Why mapping your DNA may be less reliable than you think - The Globe and Mail
The PGP's deep dive into human DNA overturns the notion that the healthy inherit from their parents two matching sets of 23 tidy chromosomes that line up like soldiers. Indeed, it finds major structural differences not only between people, but between chromosomes in the same person. "People are walking around with these massive chunks of chromosomes missing, and [duplications] that affect multiple genes," Dr. Scherer says. "When I was a student, these things were associated with Down Syndrome, or DiGeorge Syndrome, so to see how structurally different we are, and how many examples there are in this [small, healthy] group – it amazes me."

Most research on DNA has focused on the single letter "typos" in genetic code as signposts of disease. But the PGP study concludes that further research should include places where whole "sentences" or "paragraphs" of code may be missing, or upside down, or, like a stutter, repeated – a quirk known as a copy-number variation, or a CNV.
Genetics  biology  evolution  Personal  Family 
august 2018 by Jibarosoy
The Great Breakup: The First Arrivals to the Americas Split Into Two Groups - The New York Times
Dr. Malhi said that there may well have been other massive migrations in the Americas. In the new study, for example, the researchers found that ancient people in what is now Ontario, as well as living Native Americans in places like Alaska, had ancestry related to the Inuit of Greenland.

It’s possible, then, that Arctic people moved south in the past few thousand years, mixing their genes with those of ANC-B people.

One way to explore these hypotheses is to find more ancient DNA from other parts of the Americas. But first Dr. Malhi said that he and his colleagues also want to talk with living Native Americans about their histories.
Genetics  Sanchez  anthropology  natives  Race  Research 
may 2018 by Jibarosoy
Farmers assimilated foragers as they spread agriculture | Science News
Early farmers living in Sweden about 5,000 years ago carried genetic signatures of both farmers and hunter-gatherers, researchers report April 24 in Science. The findings suggest that migrating farmers bred with foragers, carrying more and more hunter-gatherer genes with them as they brought agriculture from the Middle East through Central Europe and into Scandinavia.

Not all of the foragers were brought into the farmers’ fold: At least some Scandinavian foragers resisted assimilation. These hunter-gatherers maintained a separate genetic identity and culture for at least 40 generations even though they lived only 400 kilometers from the Swedish farmers, Mattias Jakobsson, a population geneticist at Uppsala University in Sweden, and his colleagues found.
SON  state  Economics  development  Genetics  Pol.11 
april 2018 by Jibarosoy
‘Cheddar Man,’ Britain’s Oldest Skeleton, Had Dark Skin, DNA Shows - The New York Times
He had dark skin, brown curly hair and blue eyes, DNA tests suggest, upending a common assumption that Britain’s indigenous populations were all pale skinned with fair features.

He is “Cheddar Man,” Britain’s oldest complete skeleton, which was discovered in 1903 in Gough’s Cave near the village of Cheddar in Somerset, in southwest England. He lived about 10,000 years ago in the Mesolithic period, the middle part of the Stone Age.

Scientists have now reconstructed his features, demonstrating that he was part of a population of ancient Western Europeans that, scientists have shown in recent years, had dark skin. Research has shown that fair skin pigmentation — long considered a defining feature of Europe — only goes back less than 6,000 years.
Race  Genetics  anthropology  Power_materials  Passions  Groups  racism 
february 2018 by Jibarosoy
How the Western Diet Has Derailed Our Evolution | Portside
Scientists suspect our intestinal community of microbes, the human microbiota, calibrates our immune and metabolic function, and that its corruption or depletion can increase the risk of chronic diseases, ranging from asthma to obesity. One might think that if we coevolved with our microbes, they’d be more or less the same in healthy humans everywhere. But that’s not what the scientists observed.
health  PERSONAL  genetics  Food 
november 2015 by Jibarosoy
All languages come from Africa according to study
His study was prompted by a recent finding that the number of phonemes in a language increases with the number of people who speak it. This gave him the idea that phoneme diversity would increase as a population grew, but would fall again when a small group split off and migrated away from the parent group. Such a continual budding process, which is the way the first modern humans expanded around the world, is known to produce what biologists call a serial founder effect. Each time a smaller group moves away, there is a reduction in its genetic diversity. The reduction in phonemic diversity over increasing distances from Africa, as seen by Dr. Atkinson, parallels the reduction in genetic diversity already recorded by biologists.
language  race  genetics  anthropology 
february 2015 by Jibarosoy
We Are Dead Stars - The Atlantic
We are dead stars looking back up at the sky
poetry  genetics 
may 2014 by Jibarosoy
Late Pleistocene Human Skeleton and mtDNA Link Paleoamericans and Modern Native Americans
he ancestry of the earliest Americans is still debated, however, because the oldest skeletal remains from the Americas (>9 ka, the Paleoamericans) consistently fail to group morphometrically with modern Native Americans, Siberians, and other northeast Asians (6). Paleoamericans exhibit longer, narrower crania and smaller, shorter, more projecting faces than later Native Americans (7). In nearly all cases, they are morphologically most similar to modern peoples of Africa, Australia, and the southern Pacific Rim (7–9). Polymorphic dental traits currently found in East Asia also distinguish later Native Americans (10), who tend to exhibit such specialized (Sinodont) traits as winged, shovel-shaped upper incisors, three-rooted lower first molars, and small or absent third molars; from Paleoamericans, who exhibit a less specialized (Sundadont) morphology (7). These differences suggest that America was colonized by separate migration events from different parts of Eurasia (11) or by multiple
genetics  latinos  PERSONAL  Race 
may 2014 by Jibarosoy
World ancestry
This interactive map summarizes the results described in the paper "A genetic atlas of human admixture history", Hellenthal et al, Science (2014). This help page gives a brief summary of the content and structure of the page. (We also suggest reading the FAQ and the tutorial accessible under the 'Historical event' menu.) To begin, click on a labelled population on the map (or select one from the "Target" drop-down menu at top). You will see displayed details of past admixture events which we infer to have occurred in forming that population.
history  statistics  maps  genetics  sanchez 
february 2014 by Jibarosoy
Tracing Ancestry, Researchers Produce a Genetic Atlas of Human Mixing Events - NYTimes.com
The rise and fall of empires, the march of armies, the flow of trade routes, the practice of slavery — all these events have led to a mixing of populations around the world. Such episodes have left a record in the human genome, but one that has so far been too complex to decipher on a global scale. Now, geneticists applying new statistical approaches have taken a first shot at both identifying and dating the major population mixture events of the last 4,000 years, with the goal of providing a new source of information for historians.
history  Genetics  sanchez  mapping 
february 2014 by Jibarosoy
Fractal Enlightenment | Alter Your Genes and Cure any Disease
Bruce Lipton, a cellular biologist and bestselling author of The Biology of Belief, advocates the idea that we have significant control over our biology, and with our intentions and beliefs we can ‘reprogram’ or ‘control’ our genes and our lives. This challenges the traditional scientific belief that genes control life and people attribute their illnesses to genetic dysfunctions.
HEALTH  Genetics 
february 2014 by Jibarosoy
Is Your Earwax Wet or Dry? | LiveScience
A new study reveals that the gene responsible for the drier type originated in an ancient northeastern Asian population. Today, 80 to 95 percent of East Asians have dry earwax, whereas the wet variety is abundant in people of African and European ancestry (97 to 100 percent).
Genetics  sanchez  anthropology  family 
december 2013 by Jibarosoy

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