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For instance, how does one purify dNTPs at home?

Promega is over-priced, but dNTPs aren't a high-use item anyway.

Bio is still pretty expensive. Even simple techniques like PCR require highly purified reagents. For instance, how does one purify dNTPs at home?

The scientists also inserted a glowing firefly protein into the virus to track its progress. They used a light-detection "cooled charged-coupled device," or CCCD, camera to look at the glowing protein inside live mice. Because the protein was attached to the gene therapy, the researchers could see that the treatment had hit its mark.

First, what freaking protein are they talking about? Luciferase (a non-fluorescent enzyme) does come from fireflies, but you can't visualize it without luciferin, and it doesn't seem reasonable to pump a mouse full of luciferin for visualization. I'm thinking it was more likely Green Fluorescent Protein (GFP), which comes from a jellyfish, not a firefly. And it really makes no sense at all to say that a protein is attached to a gene therapy. Here is a paper about using luciferase, but I don't see any mention of using it in vivo in mice.

Also, both luciferase and GFP produce green light, which is readily absorbed by tissue. If it were infrared, it would be more believable. Maybe they removed the tumors and put sections into dishes of luciferin? Hard to say with such scant information.

To answer your original question about whether the virus actually attacks cancer cells, well, cancer is a class of illnesses. Generally one of the important regulatory proteins is screwed up by DNA damage, so the cells become immortal. Depending on the mechanism by which the cancer became immortal, the treatment will vary. Cancer cells are totally screwed up. They have indeterminate numbers of chromosomes, they overexpress certain proteins by the truckload, and some of them (such as the HeLa cell line, named after the dead woman from whom they were taken, Henrietta Lacks) can be easily cultured in vitro. The article specifically mentioned metastisized melanoma, which I guess overexpressed this p-glycoprotein. You'd have to change the target to be appropriate for the type of cancer.

On the other hand, Vascular Endothelial Growth Factor has a more critical role in initiating growth of new blood vessels - blocking VEGF has been considered to be a more fruitful approach to preventing tumor vascularization. However, this has proven to be very difficult, which is why a pharmacologic approach to kill off newly formed vascular tissue is a welcome strategy.

from Promega

However, another tenet of the patent system is the "fair use" exclusion, in which basic researchers are allowed to use patented technologies without having to pay licensing fees.

The Roche PCR patent case involved the first US case in which a company sought to claim that basic researchers were infringing on the patent, and that the "fair use" exception did not apply. Details are available from the Promega web site.

This, more than anything, was the infuriating thing about the Roche patent. Basic researchers were literally threatened by this company, for not paying exorbitant fees on an enzyme that many of us can make for pennies. Roche even produced a ridiculous hit list of basic researchers who were "infringing", based on the Materials and Methods sections of papers written by those researchers.

It's a Good Thing that Promega won this case.

However, another tenet of the patent system is the "fair use" exclusion, in which basic researchers are allowed to use patented technologies without having to pay licensing fees.

The Roche PCR patent case involved the first US case in which a company sought to claim that basic researchers were infringing on the patent, and that the "fair use" exception did not apply. Details are available from the Promega web site.

This, more than anything, was the infuriating thing about the Roche patent. Basic researchers were literally threatened by this company, for not paying exorbitant fees on an enzyme that many of us can make for pennies. Roche even produced a ridiculous hit list of basic researchers who were "infringing", based on the Materials and Methods sections of papers written by those researchers.

It's a Good Thing that Promega won this case.

While this patent is quite probably illegitimate because of the method it was obtained, it is also quite clearly NOT a patent of genetic material, i.e. it is not a DNA patent as per the article headline.

Regardless of what you think about the legitimacy of patenting of genetic codes, this has to do with processes and other technologies used to analyze and fabricate DNA, and nothing to do with the actual makeup of the codes.

In addition the article makes the error of claiming that this will make DNA research easier. Quite incorrect. Patent laws ALREADY exempt research activities from any patent infringement claims.

For some basic information on patent laws, this page is useful.

Perhaps you wouldn't mind explaining this?




http: //wwwmed.stanford.edu/center/communications/Pressr el/October97/glow.html - labmice

http://www.promega.com/pnotes/49/ 2788d/2788d.html - pictures of glowing fruitflies and plants.