Since building the first large double helices for AMGEN I have received a fair number of emails asking about the sale, renting, or other use of the models. Unfortunately, I have long ago disassembled the big blue-ribboned prototype that I had made, and the two that were AMGEN's property had been given away to hospitals or something. I still had the basic schematics, and certainly could reconstruct a helix of the original size, but new clients generally found the couple thousand dollar price tag a bit too high. Then, one day, I was approached by an editor of a genetics journal who said that his magazine might have an interest in wanting a photograph of the helix for their cover.
Some discussion was made about my possibly rebuilding an unglued helix that I would then photograph myself (since shipping the unglued model would be disastrous). Shortly thereafter, however, I had a revelation: why not build a much smaller version of a DNA helix? In addition to the obvious benefits of shorter building time, easier shipping, and less cost in materials, I realized that for the cover of a magazine or such, a smaller model might actually look better.

Finally (and this is complete LEGO-luck), I did my homework and learned that a DNA helix is supposed to make one complete rotation every 10.5 rods. I have also built a version of this size helix using transparent 1x1 cylinders (the base is also round now). Imagine a set of blocks that has only four shapes, or an alphabet that has only four letters. I expect something like the Wedding Cake to generate a steady stream of inquires (it does), but I never would have guess that a DNA double helix model would be so popular.
Now, I didn't have any pictures of the helices beyond the ones on my website, and certainly none of high enough quality to produce an 8.5" x 11" picture at 300 dpi.
But, I could not guarantee that my photographs would be of the best quality, and, thus, the journal could not guarantee that it would use the images (and I would not be monetarily compensated for my time unless the photos were used). Even without gluing the model holds together because it is so light (I still glue it so that it will survive shipping).

The one editor of the journal likes the new model (and the fact that the cost would be significantly less); however, he is just one of several editors for the journal, and evidently some aren't too keen on the idea of putting a "toy" on the cover. Patent and Trademark Office in the biotechnology division was also interested in the DNA helices; he sent me an email asking if they could rent, buy, or borrow one of the large models. I was content to build one as planned and count the rods per turn afterward to see how close I came.
AMGEN had failed to tell me during the original construction that DNA molecules are supposed to twist to the right as one goes up; I had built the large versions backward (I never studied genetics in high school or college, so I knew nothing about DNA, really).

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