Astonishing advance in DNA editing

[Flyer]

I attend a discussion group that typically has rather wide-ranging discussions. In the most recent one, I learned about something called CRISPR.

CRISPR is actually a naturally-occurring, ancient defense mechanism found in a wide range of bacteria. As far as back the 1980s, scientists observed a strange pattern in some bacterial genomes. One DNA sequence would be repeated over and over again, with unique sequences in between the repeats. They called this odd configuration “clustered regularly interspaced short palindromic repeats,” or CRISPR.

This was all puzzling until scientists realized the unique sequences in between the repeats matched the DNA of viruses—specifically viruses that prey on bacteria. It turns out CRISPR is one part of the bacteria’s immune system, which keeps bits of dangerous viruses around so it can recognize and defend against those viruses next time they attack. The second part of the defense mechanism is a set of enzymes called Cas (CRISPR-associated proteins), which can precisely snip DNA and slice the hell out of invading viruses. Conveniently, the genes that encode for Cas are always sitting somewhere near the CRISPR sequences.

Everything You Need to Know About CRISPR, the New Tool that Edits DNA

It turns out that CRISPR is basically a “do it yourself” kit for editing DNA. Until now, it’s been very difficult and expensive to do that kind of thing.

With CRISPR, the situation could change: the ease and low cost may make genome editing a viable option for smaller, speciality crops, as well as animals. In the past few years, researchers have used the method to engineer petite pigs and to make disease-resistant wheat and rice. They have also made progress towards engineering dehorned cattle, disease-resistant goats and vitamin-enriched sweet oranges. Doudna anticipates that her list of CRISPR-modified organisms will grow. “There’s an interesting opportunity to consider doing experiments or engineering pathways in plants that are not as important commercially but are very interesting from a research perspective — or for home vegetable gardens,” she says.

http://www.nature.com/news/crispr-the-disruptor-1.17673

You can actually buy CRISPR kits on the internet. Here is one of several examples that I found.

Precision gRNA Synthesis Kit

[Iggy]

CRISPR Cas-9 editing has already led to some ethical conundrums.
The Chinese have already used the technique to edit the genome in non-viable human embryos.

[Rigamarole]

@Flyer

You can actually buy CRISPR kits on the internet. Here is one of several examples that I found.

Precision gRNA Synthesis Kit

Oooh… will this finally allow me to create the elusive half-man, half-bear, half-pig?

[Bryan_Ekers]

God schmod, I want my monkey-man.

[up_the_junction]

More to the point, will your monkey-man want you.

[WordMan]

Let’s put it this way: over the past 3 summers, my High School son has been interning at a genetics lab. He was doing CRISPR Cas9 - himself. They are doing precision genetics - testing specific gene mutations for their response to cancer drugs. He was assigned certain combinations, so he prepped the samples using it.

As a result I have been keeping an eye on articles. When the creator of CRISPR wants it banned/limited/regulated - and a 16 year old kid can do it with some supervision - it can be really scary to think about how this could play out.

[lazybratsche]

I am a molecular biologist (but I am not your molecular biologist, or however these disclaimers go.) My lab has done a few gene editing projects using CRISPR, and I have plans to do some projects myself. It really is a huge advance in the state of the art.

It’s a lot easier, cheaper, more efficient, and more reliable than any previous technique. If you want to genetically modify a fruit fly, you just need to spend a few weeks making the CRISPR DNA editing constructs, inject a few embryos, and screen through the second generation flies to find successfully modified flies. Total efficiency is on the order of 10%-50%.

In comparison, previous techniques like P-element insertion are less efficient (~1%) and insert genetic constructs in random locations in the genome. Editing specific locations using homologous recombination is a lot more labor intensive and less efficient, IIRC requiring 3-4 generations with efficiency on the order of 1 in 10,000. There have been many enhancements of these techniques, enough to write a small textbook on the topic, but even the best techniques aren’t anywhere near as good as CRISPR.

(FWIW ThermoFisher probably won’t sell to any schlub on the internet, their website is intended for customers in academic and private labs. But you don’t really need a kit…)

[running_coach]

@Rigamarole

Oooh… will this finally allow me to create the elusive half-man, half-bear, half-pig?

He would have an enormous schwanzstucker.

[Icarus]

Hmmm…

A CRISPR kit, a cheap 3D Printer, set myself up at a swap-meet and I’m in business!

Is your kid ugly? We can fix that!

You say you want a fluffy Wookie-mermaid? We can make one!

Endless Bacon Tree? Coming right up!

I’ll be rich, RICH!

[botsgotme]

It sounds like antibiotics will soon be obsolete-we can now fight bacterial diseases by engineering harmless versions of disease causing bacteria-drive them out of existence for all time. No more TB, whooping cough,tetanus, etc.

[Smeghead]

@botsgotme

It sounds like antibiotics will soon be obsolete-we can now fight bacterial diseases by engineering harmless versions of disease causing bacteria-drive them out of existence for all time. No more TB, whooping cough,tetanus, etc.

Um…that’s not really how bacteria work.

[mind_the_gap]

I spy the law of unintended consequences rubbing its sticky little hands together.

[lazybratsche]

@botsgotme

It sounds like antibiotics will soon be obsolete-we can now fight bacterial diseases by engineering harmless versions of disease causing bacteria-drive them out of existence for all time. No more TB, whooping cough,tetanus, etc.

Hardly. Every genetic modification technique needs a way to select for successfully modified organisms. With flies that will be typically with a gene that changes eye color, and with bacteria it’s usually a gene for … antibiotic resistance. Plus, less virulent modified pathogens will be at a competitive disadvantage compared to the more virulent unmodified strains.

(Even with CRISPR you’ll need to screen for a phenotype, and then sequence the intended insert site to confirm that your DNA was put in the right place. The revolution here is that you only need to select a handful of organisms for sequencing, rather than dozens or hundreds.)

[Doctor_Jackson]

@up_the_junction

More to the point, will your monkey-man want you.

And if he takes a selfie, who owns the copyright?

[Smeghead]

Although this is an astonishingly powerful advance, I think many lay people fail to realize how many unknowns remain. The ability to make changes is only half of the equation. The other half is figuring out WHICH changes to make to get the desired output. Figuring that out takes a LOT of work. Sure, there are some low-hanging fruits, like fixing cystic fibrosis or muscular dystrophy, but some of the wilder ideas like, I don’t know, growing human organs in pigs or changing our eye or hair color will take a lot more research if they’re not entirely impossible.

The other factor to take into account is that some changes can only be made effectively during development. Once a structure is built in the adult, it may very well be fixed. The ability to grow a structure from scratch is very different from the ability to remodel a structure, or to tear it down and grow a new one. Generally speaking, our bodies don’t have the latter ability, and that’s not the sort of thing that we can just engineer and introduce.

[Grestarian]

@running_coach

He would have an enormous schwanzstucker.

@Rigamarole

Oooh… will this finally allow me to create the elusive half-man, half-bear, half-pig?

@running_coach

He would have an enormous schwanzstucker.

With that kind of head, it would at least be able to do simple pre-algebra (like adding fractions) better than…well, a lot of us. :rolleyes:

But seriously, I find it interesting to juxtapose this news with last year’s not-quite-startling scientific revelation that people are very much human body PLUS various symbiots (sp?) – particularly various flora and fauna on the skin and in the gut.

So, even while the WP article that’s linked to the Conundrum post above notes that therapeutic and commercial use of this technique for human beings is still decades away (at best), I suggest it’s many decades away because there’s more to changing, for instance, Crohn’s susceptibility, than merely altering the DNA of the human (host).

–G!

[ITR_champion]

@Flyer

I attend a discussion group that typically has rather wide-ranging discussions. In the most recent one, I learned about something called CRISPR.

Everything You Need to Know About CRISPR, the New Tool that Edits DNA

It turns out that CRISPR is basically a “do it yourself” kit for editing DNA. Until now, it’s been very difficult and expensive to do that kind of thing.

CRISPR, the disruptor | Nature

You can actually buy CRISPR kits on the internet. Here is one of several examples that I found.

Precision gRNA Synthesis Kit

I had never heard of CRISPR before. Thank you for sharing; those links made for fascinating reading.

[Rigamarole]

@Grestarian

With that kind of head, it would at least be able to do simple pre-algebra (like adding fractions) better than…well, a lot of us. :rolleyes:

You obviously didn’t get the reference.

[Smeghead]

For a slightly more in-depth look at this, I like this review a lot: CRISPR/Cas9 and Genome Editing in Drosophila - ScienceDirect