A bizarre controversy is unfolding over an impending low-calorie soda from Pepsi (PEP), which the company is creating with the help of the biotech company Senomyx (SNMX). Numerous anti-abortion groups have started a boycott of Pepsi products because they say Senomyx, which develops new ingredients intended to enhance sweetness and other flavors, has done so using embryonic kidney cells that were originally taken from an aborted baby.

This accusation presents a two-fold problem for Pepsi. The first, most obvious one is that the beverage giant has now ardent anti-abortionists breathing down its neck. The second, and possibly more troubling, issue is that some of Pepsi's attempts to create groundbreaking and healthier products are now associated with fetal kidney cells.

What Senomyx is up to

Is this claim true? Neither Pepsi nor Senomyx returned calls, so we don't know the companies' side of the story. But a perusal of Senomyx's patents suggests that it may well be. All but 7 of the company's 77 patents refer to the use of HEK 293 (human embryonic kidney) cells, which researchers have used for decades as biological workhorses. (For the bio-geeks among you, these cells offer a reliable way to produce new proteins via genetic engineering.)

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The company appears to be engineering HEK cells to function like the taste-receptor cells we have in our mouth. This way, Senomyx can test millions of substances to see if they work as different types of taste enhancers without subjecting human volunteers to endless taste tests.

To non-scientists this may sound a bit strange, but the reality is that HEK 293 cells are widely used in pharmaceutical research, helping scientists create vaccines as well as drugs like those for rheumatoid arthritis. The difference here is that Senomyx's work for Pepsi is one of the first times the cells have (potentially) been used to create a food or beverage. (And it's important to note that no part of a human kidney cell are ever a part of Senomyx's taste enhancers or any finished food products.)

When bioscience meets the mass market

For Debi Vinnedge, who runs the anti-abortion group Children of God for Life, that doesn't matter. "It's the eeew factor. It strikes a really strong reaction in people," she said in an interview. She points to the fact that one of Senomyx's patents (not one for a product Pepsi would be using) refers to the way company scientists used mifepristone to get unstable HEK cells to respond -- mifepristone being more commonly known as RU-486, the abortion pill.

Vinnedge, who has been campaigning against the use of embryonic cells for years, unearthed the information about Senomyx and HEK by combing through the company's patents.

Even though HEK 293 cells trace their origin to a single fetal kidney back in the 1970s -- everything since has come from cultured cell lines -- Vinnedge considers their use unethical because it indirectly creates a market for aborted fetuses and encourages scientists to hunt for new embryonic cell lines. She argues that Senomyx could use other, non-fetus-based cell lines, such as those from animals.

Pepsi is not alone

Pepsi is hardly the only company working with Senomyx. Kraft's (KFT) Cadbury unit, Nestle (NESN), the soybean company Solae and the flavor company Firmenich also have partnerships, and Vinnedge and her supports have sent letters to those companies as well. Senomyx says that Nestle is selling products with its flavor ingredients, though it doesn't specify which products.

Pepsi, though, remains the biggest and most obvious target. A New Yorker article last month on the company revealed that a new, 60% less sugar soda could be out within six month, but David Cohn, a Raymond James stockbroker who's been following Senomyx for several years, says he doesn't expect a product until 2013.

Plenty of time for Pepsi to craft its side of the story, should it decide to tell it.

Image Flickr user Steve Rhodes

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