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Blue eyes or brown? The age of easy gene-editing is here

By Chris Davis | China Daily USA | Updated: 2015-11-25 11:37

Animal breeding is nothing new. And it has paid off. What a stale and dull place the world would be without St. Bernards, Belgian draft horses, Persian cats, all the domesticated critters selectively bred and crossbred for their valued traits, be it speed, color, strength or demeanor. The registry of thoroughbred horses alone makes the House of Windsor's family tree look like a mere mulberry bush. And the American Kennel Club's 160-plus breeds of dogs are stunning proof of the vast pallet of color, shape and size DNA offers.

All of that kind of breeding, of course, was done the old-fashioned way. Selecting the right pairs, checking their lineage to avoid inbreeds, rolling the dice and waiting out Mother Nature's timetable to see if the match-ups produced the desired results - like transforming a bloodhound into a Golden retriever.

Well, apparently those days are past. Scientists have a new tool that not only speeds the whole process up, but also lets them target the desired result with pinpoint accuracy. It's called CRISPR and its place of birth is presently a point of contention between scientists at MIT and Cal-Berkeley. But a few things about it are clear: it's cheap, easy to use, getting easier and more efficient all the time, and the Chinese scientific community is very into it.

CRISPR is one genie that is not going back into its bottle any time soon.

CRISPR ( it stands for "clustered regularly interspaced short palindromic repeats", whatever that means) basically uses enzymes to, what we call in publishing, "line edit" strands of DNA, a task that, as Darwin suggested, the randomness of Nature has been doing since life began.

Now, with a genome road map and CRISPR, anything goes, and it's going fast, so fast that there doesn't seem to be enough time to think through all of the ethical implications, much less the risks. Genetically "edited" organisms could wreak havoc in the ecosystems they evolved with, for one thing.

As Stanford biologist Stanley Qi told the journal Nature: "This power is so easily accessible by labs - you don't need a very expensive piece of equipment and people don't need to get years of training to do this. We should think carefully about how we are going to use that power."

The current issue of Scientific American reports how CRISP is being used in western China at the Shaanxi Provincial Engineering and Technology Research Center for Shaanbei Cashmere Goats, which yield what is considered the world's best cashmere. Scientists there have used CRISPR to create "a new kind of goat, with bigger muscles and longer hair than normal."

Scientists basically went into goat embryos and "deleted" the two genes that hold back muscle and hair growth. The pay off was 10 kids with bigger muscles and longer hair and "no other abnormalities," the report said. To geneticist Lei Qu, it's just "a simple way to boost the sale of goat meat and cashmere sweaters from Shaanxi."

The number of scientific papers worldwide describing uses of CRISPR are outstripping those using other techniques, and China is part of the trend. CRISPR-tweaked sheep, pigs, monkeys and dogs are described in what SA describes as a "flurry of papers by Chinese scientists."

Its use is a "priority" with the Chinese Academy of Science, according to Minhua Hu, a geneticist at the Guangzhou General Pharmaceutical Research Institute who was part of a team that produced Hercules, an unusually muscled beagle who lives up to his name.

Beefing up meat on the hoof to feed a growing appetite for protein is well within the ethical realm of animal husbandry. But the big elephant in the room remains - where do you stop?

And that line seemed to be crossed last April when Chinese scientists announced that they had used CRISPR to modify human embryos - the first time in the world.

Granted they were nonviable embryos, obtained with the consent of a fertility clinic, and their aim was to edit out a gene that leads to beta-thalassemia, a deadly genetic blood disorder.

But the work caused an uproar and the warnings issued then still ring true today, even more so perhaps.

Harvard biochemist and stem-cell expert George Q. Daley said the risks included unwanted or harmful defects. "It would be distressing to cause one disease while attempting to erase another," he told China Daily.

He also said that "genetic engineering will raise the most fundamental issues over how people are to view our humanity in the future, and whether we are going to take the dramatic step of taking control of our genetic destiny."

It already has.

Contact the writer at chrisdavis@chinadailyusa.com.

 

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