Confusion over Cloning
Ethical debates over cloning are confusing enough, but even without the ethics issues the terminology of cloning is extremely confusing. Scientists bat around the word in many different contexts, often with subtly different meanings; if you don't know the biological background, it's easy to become disoriented.
The most common use of the word cloning (in science, although maybe not in politics) has nothing to do with embryos, stem cells, or 10,000 copies of Jango Fett on the planet Kamino. It essentially means this (we'll call this definition 1): to make a copy of a piece of DNA, usually in order to put it into some form that's useful in the lab. So the phrase "I'm going to clone gene X into vector Y" is nerdspeak for: "I'm going to take the gene I'm interested in studying and put it into a little circular piece of DNA, which I can then make many copies of (by growing it in a harmless strain of bacteria), so that I can do my experiments."
Cloning in this sense is usually trivial (although it may involve weeks of frustration in the lab trying to get it to work!). But there is another related meaning of the word cloning that implies discovery of something new, although with the advent of complete genome sequencing, this use of the term is becoming obsolete. Back before the turn of the millennium, it was a lot of work to find that one stretch of DNA coding for say, an alcohol metabolizing enzyme: you knew that gene was out there, but you didn't know what its DNA sequence was or where to find it. So people would spend years trying to grab that one little stretch of DNA coding for the enzyme, and when they found it, they would proudly announce "I've cloned a new gene!" (we'll call this definition 2).
Today however, we know where most of the genes are - we can go to the UCSC Genome Browser and look up where in the human genome the cannabis receptor gene or an alcohol dehydrogenase gene is located. Cloning a gene now doesn't mean discovering a gene, the way it used to. So what are we to make of a press release like this one: "Researchers report the cloning of a key group of human genes, the protein kinases"? Did these guys discover new genes?
No, they didn't, but they did clone these genes into a form useful for doing experiments in the lab. But in this case, they are using the term 'clone' in yet one more different sense: not only did make copies of these genes and put them inside some sort of useful vector (definition 1, above), but they managed to get the spliced form of these genes. In most multi-cellular organisms, genes are scattered in pieces in our genomes - a little coding piece is followed by a long non-coding piece, and then come another coding piece, etc. So your cells have to splice all of the little pieces together into one final coding form. Thus researchers will clone a gene by taking the final, spliced form and putting it in a useful vector (definition 3, only slightly different from definition 1). And, as you can read here, this is what the researchers really did - they didn't discover new protein kinase genes, they just took the final, spliced forms of these genes and put them into a format useful for experiments. It's not a new discovery, but it is a very useful technology that many different researchers can use to study these genes, many of which play a role in cancer.
If you're not hopelessly confused yet, I'm impressed. It's conceptually simple, but the terminology is tricky. When you know the terminology, it's much easier to understand the many science stories out there about cloning.
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