Note (12/2015): Hi there! I'm taking some time off here to focus on other projects for a bit. As of October 2016, those other projects include a science book series for kids titled Things That Make You Go Yuck! -- available at Barnes and Noble, Amazon and (hopefully) a bookstore near you!

Co-author Jenn Dlugos and I are also doing some extremely ridiculous things over at Drinkstorm Studios, including our award-winning webseries, Magicland.

There are also a full 100 posts right here in the archives, and feel free to drop me a line at with comments, suggestions or wacky cold fusion ideas. Cheers!

· Categories: Biology, Genetics
What I’ve Learned:

Wild type: tame on the outside, tamer on the inside.
“Wild type: tame on the outside, tamer on the inside.”

You would think the term “wild type” would describe the craziest, wackiest, furthest-out-there members of a species. Teen wolves. Mutant carny folk. Donald Trump.

But no.

In genetic terms, “wild type” refers to what you’d find “in the wild”, meaning the usual, most common, textbook examples. The ho-hummers. Been there, seen that.

When biologists describe things as wild type, they’re typically referring to one of two things: genotype or phenotype. The words look and sound nearly the same, but there’s an easy way to keep them straight:

Genotype starts the same way as “gene”, and indeed refers to DNA sequence, where genes live. A wild type genotype is one that matches the sequence most commonly found in the population. So what are you called if you have a different sequence, and your genotype varies from the norm? A mutant.

Not in a bad way, necessarily. But a mutation — either in one of your cells, or in one of your ancestors’ cells which was passed on to you — is how variation gets into genetic sequence, and those variations are tremendously important. Without mutations, we’d all have the same DNA. We’d all be susceptible to the same diseases. We’d have no flexibility as a species to survive. And we’d only have Teenage Ninja Turtles movies. Who the hell would watch those?

(Of course, according to Gattaca, we’d also all look like Jude Law and Uma Thurman. I’m sure there are downsides to that, somehow. I’ll let you know if I think of any.)

Then there’s phenotype, which starts with “phen”, so the easy way to remember that is “it’s not the ‘gene’ one”. Or make up something about “phenomenal”, maybe. Or “phenylalanine”. I don’t know. What am I, your mnemonics coach?

What phenotype refers to is outward appearance or traits. One or more DNA sequence changes (or genotypes) may lead to noticeable physical changes, or phenotypes. In fruit flies, for instance, there’s a gene that controls eye color. Certain genotypic changes, or mutations, in that gene lead to a phenotypic change: instead of beady little red eyes, the flies have beady little white ones.

Not as dramatic a physical change as you get from frappe-ing a fly’s DNA up with Seth Brundle’s, perhaps. But still, a distinctive phenotype — one for wild type, and one for mutants.

In the phenotypic sense, there is no single “wild type”. No one set of characteristics is standard, with offshoots of eye color and skin shade and curliness of hair radiating from it. You can compare variations to each other, but there’s no reference person or animal or bacterium to call ideal.

Likewise, you can come up with a “reference genome” for a species — and people have, for humans and fruit flies and rats and plants and plants and hundreds of other species. But each of these is just an average of the DNA that’s tested. One particular genotypic locus might have a certain sequence in fifty-one percent of the population, so it becomes “wild type”. But everyone else is then a “variant”, and none of us have the same set of millions of variants currently known. We’re all mutants, if you compare our DNA to the human reference genome, though we’re considered wild type in the majority of genomic positions.

Well, most of us are. Not counting Teen Wolf. Or carny folk. Or Trump. The only “wild type” of thing about them is their hair. Their scary mutant hair.

Actual Science:
Science EncyclopediaWild type
University of MiamiWild type vs. mutant traits
The ScientistGM mosquito cuts wild-type numbers
UCSCThe biology of the banana

Image sources: IJMM (wild type vs. mutant sequence), Geek History Lesson (Michael J. Wolf), Junkee (Teenage Wild Type Ninja Turtles), More Than Words (hairpiece with a Trump problem)

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· Categories: Biology, Genetics
What I’ve Learned:

Optogenetics: science--invented, laser doge-approved
“With optogenetics, you won’t just ‘see the light’. You’ll feel it.”

The brain is a pain in the ass, scientifically speaking. And scientific-researchly speaking, which is probably a real thing.

Studying the brain is unusually tricky. It’s a complicated organ with billions of cells, electrical signals whizzing everywhere and neurotransmitters getting passed back and forth like the last beer at a tailgate. You want “simple”, go study an appendix. The brain is not for you.

Also, the brain comes not-so-conveniently wrapped in a hard candy shell called a skull. To reach it, you’ve got to drill through bone — and then dig through brain, if the bit you’re after is in the middle. For decades, brain science was like trying to yank grapes out of Grandma’s Jell-O without breaking the mold. As any eight-year-old can tell you, that’s damned near impossible.

Then there’s the scale. Most organs you study with a microscope, or even a camera. Drop a miniature Nikon down (or up) someone’s gut and watch a day in the life of a colon unfold in real time.

Or slower, if your test subject is a big fan of fiber.

But the brain operates at millisecond speed. Blink, and you miss a million firing synapses, lighting up the cerebellum. And the cerebrum. And that other bit — the one for remembering numbers and science facts and what parts of brains are called. Mine doesn’t work, apparently.

How can scientists possibly get around all these problems? Enter optogenetics, which allows neurocowboys a new way to put eyes on the brain. Literally. (Almost.)

The ‘opto-‘ part of the name suggests light (or eye doctors), and refers to light-sensitive proteins — like those in our eyes’ rod and cone cells — found in species like fruit flies, algae and bacteria. These proteins react to specific wavelengths of light; by snipping out the DNA sequences coding them (hence the “-genetics”) and linking them to genes in test animals, scientists can set off signals in those animals’ brains — just by turning on a flashlight.

A very special kind of laboratory flashlight. Very wavelength. Much science. Wow.

Now researchers can trigger — and measure — brain events at the speed of light. They’ve even developed wireless versions of their flashy-light and brain-detect-o-matic devices, allowing them to study animals running free in the lab. Or “free” in a cage. But not attached by the forehead to an industrial science laser. Which is nice.

The techniques are fairly new, but have already changed the neurobiology game. Among other things, scientists have used optogenetic methods to implant false memories (and sexy thoughts) in fruit flies, flip-flop social behavior in mice, relax muscles in worms, break habits in rats and kill pain (again in mice) with a flash of light. Creepy Island of Doctor Moreau vibe aside, this research could someday have important applications in human medicine. Also, with all the flashing lights and artificial mind altering, the lab animals just think they’re at tiny adorable raves.

One final measure of the impact of optogenetics: In 2010, it was named scientific “Method of the Year”. Presumably, it beat out “stash your samples on ice overnight so you can duck out for Happy Hour”. For scientists, that’s a huge upset.

Image Sources: ExtremeTech (lab mouse), Jello Mold Mistress (Jell-O mold), NoodlyTime (laser doge), Redshirt Knitting (mouse rave)

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