Genetic audit uncovers hidden ingredients of Chinese medicine
DNA sequencing tests on 15 popular traditional Chinese medicines seized by Australian border officials reveals a variety of potential toxins, allergens — and even traces of endangered animals.
For desperate people suffering from diseases that are debilitating or still incurable, traditional Chinese medicines are often the “courts of last resort.” Hundreds of thousands of people afflicted with cancers, spinal cord injuries, Lou Gehrig’s disease, multiple sclerosis, diabetes, HIV/AIDS and other diseases turn to these medicines to ease pain or improve the quality of life.
And it’s no wonder, as traditional Chinese medicine (TCMs) have been used for 3,000 years and are an integral part of Chinese culture. In recent decades, the practice has spread across the world and gained popularity, spawning a multimillion-dollar global industry.
But are these medicines safe?
Health practitioners are by no means against TCMs. In fact, the World Health Organization backed traditional Chinese meds in 2008, endorsing an international agreement that promised to give these meds a foothold in health systems around the world.
The “Beijing Declaration” was inked at the first Congress on Traditional Medicine in Beijing in November 2008. The WHO-drafted document called on United Nations members to create policies ensuring the safe and effective use of traditional medicines and systems for licensing practitioners, as well as encourage communication between Western and traditional practitioners.
In the United States, such “complementary and alternative medicine (CAM)” techniques — which include TCM — are accepted even by national health authorities like the National Cancer Institute. Defined as “a group of different medical and health care systems, practices and products that are not presently considered part of conventional medicine,” CAMs are often combined with conventional medicine for an integrative medicine approach to the treatment of cancer, HIV/AIDS and other conditions. There’s even a National Center for Complementary and Alternative Medicine (NCCAM) that’s in charge of checking that these CAMs are safe and effective.
Are traditional Chinese meds regulated?
Still, despite this openness– and the billions of dollars in worldwide sales racked up by traditional Chinese meds — only a small number of TCM products have been validated in scientific trials and the booming TCM industry isn’t well regulated.
Again and again, scientists — including some from the Food and Drug Administration — have found a number of traditional Chinese medicines to be adulterated with pharmacological drugs, in a bid to increase their effectiveness.
What’s more, researchers are finding it hard to pin down and standardize the active ingredients of TCMs, since these are often found in plant extracts that have regional or seasonal variations. Often, because their ingredients are not explicitly detailed, TCMs slip under the radar of regulatory agencies in the U.S., Europe, Canada and Australia. Meanwhile, it’s proven difficult even to just find out what TCMs are made of.
That’s why — despite a growing number of cases detailing adverse reactions — concerns about the efficacy, legality and safety of TCMs have remained unaddressed mainly because there was no solid method to determine their ingredients. That is, until now.
In the past, researchers run assays for toxic compounds and used DNA tests to find out whether a specific plant or animal was present in traditional Chinese meds. But because mislabeling is rampant, researchers don’t always know where to start — what to look for. Conventional approaches will miss many of the species that are present, says Dr. Mike Bunce, a geneticist at Murdoch University near Perth, Australia, who led a new study on TCMs.
Now Dr. Bunce’s team of Australian researchers has turned to a technique that can rapidly read thousands of DNA strands — next-generation DNA sequencers.