Chris Knowles, Assistant Professor at the Oregon Wood Innovation Center of Oregon State University wrote a very educational piece on “stable isotope analysis” for us last year. He’s back to teach us about the partner technology, DNA analysis.
Chris, thanks for doing this again. So first, DNA—why should we learn about this?
That’s an easy one. Legislation aimed at mitigating illegal logging such as The Lacey Act and the European Union Timber Regulation have made it necessary to be able to accurately identify the species of wood products and determine the origin of these products.
However, it is often difficult, if not impossible, to identify the species of a piece of wood using traditional wood identification methods. DNA analysis has been shown to significantly improve the identification process by comparing your sample to a set of reference samples. DNA analysis is also being promoted as a tool that can be used to determine the origin of products.
OK, give us the DNA ABC’s.
DNA is the hereditary material, or genetic code, of living organisms. DNA stores biological information about living organisms (and organisms after they die). Almost every cell in a human has the same DNA. DNA is usually stored in the nucleus of the cell, although some DNA is stored in the mitochondria of cells.
If you watch any crime series on TV you are familiar with the way Hollywood claims we can use DNA to identify anything and everything biological. Of course as you can imagine, Hollywood stretches DNA analysis techniques on TV beyond the actual current limits of science.
In humans, the majority of our cells have some DNA in the nucleus and we can use DNA extracted from these cells to compare to DNA of a reference sample with a fairly high degree of certainty.
So it’s the same thing for trees, right?
Unfortunately, trees are not like humans and trees have limited amounts of DNA present in the living cells of trees. To complicate matters, most of the cells in a standing tree are dead and DNA degeneration (or breaking down into smaller pieces) begins soon after the cells of the tree die. This means that it is considerably more difficult to extract useable DNA material from wood cells than it is from human cells. Luckily, geneticists have figured out methods to reliably extract useable DNA material in most cases.
But I think that’s enough of the science of DNA – I want to talk about the practical issues in using DNA analysis as a tool for tracking the origin of forest products.
After all, there has been a lot of discussion in recent years about utilizing DNA analysis as a tool to reduce illegal logging. When used appropriately, DNA analysis can be an effective tool as part of a company’s due diligence or due care program. This tool can be used to help confirm the country of origin, region of origin, and with the appropriate reference materials, may even be able to identify the stand of origin.
OK, then next week we’ll tackle using DNA analysis in the real world of international wood trade. Thank you, Chris! And for the readers, in the meantime, if you’d like more information about DNA in the timber trade, these two articles might be useful: