A Brief History of Everyone Who Ever Lived: DNA, individuals, and species

British geneticist Adam Rutherford is one of the country's great science communicators, an alumnus of Nature whose work we've celebrated here for many years; with his second book, A Brief History of Everyone Who Ever Lived, Rutherford reveals how the century's astounding advances in genetic science reveal just how little we understand about our genes -- and how our ideas about race and heredity are antiquated superstitions that reflect our biases more than our DNA. (See the bottom of this post for an important update about the upcoming US edition!)

Controversy over DNA sequencing of 90 Egyptian mummies

One of the most hotly-contested fields of genetics revolves around the genetic lineage of ancient Egyptians. A new study of 90 Pre-Ptolemaic, Ptolemaic, and Roman mummies raises as many questions as it answers. Read the rest

The genetics of photosensitive sneezing, explained

If you're among the one in four people who sneeze when you move from a dark place into the sunlight, this nifty little explainer from a fellow traveler gives a great overview of causation theories over the millennia. Turns out it is just one transposed letter in the second chromosome that causes the effect. Read the rest

Cute two-faced calf is oldest of its kind to survive

Meet Lucky, a two-faced calf who lives in Campbellsville, Kentucky. Lucky is just over a month old but may be the oldest animal of its kind to survive with the genetic abnormality, called diprosopus. From National Geographic:

The calf was named Lucky by the McCubbins' five-year-old daughter, Henley, after her parents told her the rare animal was lucky to be alive. Most such genetic or developmental defects are aborted in the womb, although a few make it to birth. Most of those die within a few days.

For a two-faced or two-headed animal to make it to adulthood is extremely rare. It's considered ultrarare in the wild, although two-faced cat "Frank and Louie" lived to at least 12 years old, thanks to the care of its owners.

So far, Lucky has been doing well, the McCubbins said, although the middle two of her eyes don't work. She can only walk in circles and falls down a lot.

Lucky needs some help eating, and both mouths move at the same time.

Read the rest

Laser shines through fly's skin, controls its heart by activating doped cells

Eliza writes, "A researcher from Lehigh University has invented a light-based pacemaker for fruit flies, and says a human version is 'not impossible.' The pacemaker relies on the new technique of 'optogenetics,' in which light-sensitive proteins are inserted into certain cells, allowing those cells to be activated by pulses of light. Here, the proteins were inserted into cardiac cells so the researchers could trigger the contractions that produce heartbeats." Read the rest

Genocide, not genes: indigenous peoples' genetic alcoholism is a racist myth

I've heard -- and repeated -- the theory that addiction rates among indigenous people in the Americas was caused by genetics -- specifically, that "new world" populations hadn't gone through the European plague years' genetic bottleneck that killed everyone who couldn't survive on alcoholic beverages (these having been boiled during their production and thus less likely to carry infectious diseases). Read the rest

Gene therapy restored hearing in deaf mice

Researchers partially restored hearing in deaf mice with a certain kind of genetic hearing loss by inserting working copies of the mutated genes. Eventually the technique could lead to gene therapy for certain causes of human deafness. Read the rest

Genomic sequencing finds no single gene basis for extreme longevity

Whole genome sequencing has not found any single gene variation responsible for extreme longevity, according to a paper published in PLOS ONE:

We have sequenced the genomes of 17 supercentenarians (over 110 years of age) to see if we could uncover the genetic basis for their extreme longevity. We analyzed rare protein-altering variants, but found no strong evidence for enrichment of either a single variant or a single gene harboring different variants in female Caucasian supercentenarians compared to controls.

The full genomic sequences have been published, allowing other researchers to build on the data set.

  Read the rest

Video: Bringing back extinct species

In recent years, the possibility of reviving extinct species by recreating their genomes has become a reality. First on deck for "de-extinction" are the woolly mammoth and passenger pigeon. But is this a good idea? KQED's QUEST takes a look: "Reawakening Extinct Species" Read the rest

"Duon" is just a new name for something we already knew about

Over the last couple of days, you might have heard about the "duon" — a "second" genetic code that's being hyped as a radical new "breakthrough" in science.

Based solely on the number of words I've put in quotations here, you can probably guess that the actual news doesn't really match the hype. Read the rest

Why 23andMe can't tell you everything about yourself (yet)

How can a mild-mannered grasshopper turn into a ferocious locust? Why are humans humans when we have share 80 percent of the same genetic material with a cow? In a fascinating long read at Aeon, David Dobbs delves into the differences between genetic change (evolution as you probably learned it in school) and genetic expression (the amazing powers of natural selection that scientists are only now starting to really understand). Read the rest

23AndMe issues statement on FDA smackdown

Distributed today to all users of the 23andMe home genetic testing service, after the FDA ordered the firm to halt sales of new kits:

Dear 23andMe Customers,

I wanted to reach out to you about the FDA letter that was sent to 23andMe last Friday.

It is absolutely critical that our consumers get high quality genetic data that they can trust. We have worked extensively with our lab partner to make sure that the results we return are accurate. We stand behind the data that we return to customers - but we recognize that the FDA needs to be convinced of the quality of our data as well.

Read the rest

23andMe vs. the FDA in less than 4 minutes

At what point does interesting-but-potentially-incorrect-or-misleading information become a potential threat to health? How do you regulate a product that current regulations were never set up to handle? The University of Michigan's Risk Science Center put together this quick cartoon that neatly summarizes the problems and questions at the heart of the FDA's crackdown on 23andMe, which Xeni wrote about on Monday.

A couple of other smart takes on this that have come out in the past couple of days: • Genomics expert Michael Eisen delves deeper into the question of how we should regulate personal genetic testing. • Journalist David Dobbs rounded up some diverse opinions. You should pay attention to his blog. He's been doing a lot of great reporting on genetics and culture and is planning on publishing a longer piece on the 23andMe stuff later this week. Read the rest

Is the yeti related to an ancient polar bear?

Is the yeti actually some hybrid of ancient polar bear and brown bear? University of Oxford geneticist Bryan Sykes has analyzed DNA from what's purported to be yeti hair samples. Read the rest

Do IQ test results mean anything at all?

The answer is yes — but only in certain circumstances and that "yes" comes with a whole bunch of caveats. At Discover, Emily Sohn has a nice basic primer on what we know now about intelligence testing and what your score on an IQ test does and doesn't mean. Read the rest

Two redheads can have a brunette child

Turns out, whether or not you are a ginger is not determined by the simple genetics of a single gene. In fact, the pigment that causes red hair is likely present in many brunettes. What matters more seems to be how much of the ginger-hiding brunette pigment you have — and the genetics that determine that are a lot more complicated. Which, frankly, makes the brunette-guy-with-red-beard phenomenon make a whole lot more sense. Read the rest

Genetics: Not a "miracle", but still pretty damn strange

Besides magnetism, there's another thing that the Insane Clown Posse was on-track in categorizing as a mind-blowing mystery — Why do Shaggy 2 Dope's kids look just like him? As with the magnets, this is another situation where the obvious answer (it's genetics!) masks a much more complicated issue that science hasn't totally figured out yet. At Pacific Standard, Michael White explains why genetics is still messing with our heads, almost 150 years after Mendel:

The problem: most of the genetic differences discovered have only a very small effect. And when you add up all those effects, the result can’t possibly explain the full influence of our genes on those traits. For example, researchers have identified hundreds of DNA differences between people that influence the very strongly heritable trait of human height, but the total effect of those differences added together explains only about 10 percent of the genetic influence on height. In other words, we still can’t explain why tall parents have tall children.

Scientists have named this discrepancy the “missing heritability,” and they’ve spent the last half-decade trying to find it.

Read the rest

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