Tuesday, April 28, 2015

The apple that will not brown

It seems that someone has used genetic modification to develop, produce and sell an apple that doesn't turn brown when you cut it. It's called the Arctic Apple. When I first heard about it, I was almost sure that the Arctic Apple has found a way to defeat the enzymes that caused browning in the apple. It seems I was right. Here is a response to a reader's question about the genes that are inserted into the Artctic Apple's genome:
The *full* explanation is quite long and technical, and is best explained in the link supplied in response to David's comment (http://www.aphis.usda.gov/brs/aphisdocs/10_16101p.pdf).
To hit on some of the key points, we use a process called RNAi (RNA interference) that essentially inserts additional copies of the genes (from the same apple varieties) that control the production of the enzyme polyphenol oxidase, which drives enzymatic browning. An overly simplified way to explain it is to say that these gene sequences "cancel out" their corresponding genes, which silences them.
The amount of PPO apples produce varies quite a bit from variety to variety, so there are some cultivars that will brown more slowly, or less overall, but only Arctic apples produce so little PPO that they will not experience enzymatic browning. Technically, it might have been possible to breed an apple that had low enough levels of PPO to be comparable with Arctic apples, but it would have taken decades, with uncertain success. And, even then, you would only have one nonbrowning variety, rather than the ability to make existing popular varieties nonbrowning.
I too, know something about enzymes. Every metabolic process in our bodies is mediated by enzymes. Enzymes are the engines that perform digestion, assimilation and replication. Our bodies take advantage of the enzymes in the food. When food is cooked, the enzymes die once the temperature reaches 105 degrees. All animals, except humans that cook food, have an instinctive understanding of this feature of food, real food. After thousands of years of cooking food, humans still need to eat raw food to live. There is no way around it. You can learn more about this topic in a book called, Enzyme Nutrition.

Back to the apple. As noted above, the scientists who modify the apple to create an Arctic Apple are modifying the quantity of enzymes in the fruit to produce more of one enzyme to cancel out another enzyme, the enzyme that makes the fruit turn brown after cutting. We put food in a refrigerator to slow this process down. It's called decay. All food decays, unless it's processed food, like a Twinkie. Twinkies don't decay and they can remain perfectly preserved for decades. No animals, not even mold and bacteria will touch it. Why? It's not food.

So when I see what these scientists are doing with the apple, the Arctic Apple, I see that they're interfering with a metabolic process in the apple. This can impact the nutrition of the apple. The genes that inhibit browning in the apple are taking something away from the apple, for in order to promote the production of one enzyme over the other, you are allocating resources in the apple in ways that nature did not intend. Despite the claims of safety that promoters assert, we don't know for sure how gene expression will change in the apple.

Yes, we can sequence the genes in the new apple to verify how much of the desired enzyme is produced. The problem is that genes are actually very complicated. Apples have 57,000 genes, more than most other plants, more than humans, it seems. How genes gain expression or how they are silenced depends on their location in the genome, their relative locations to each other and even the frequency of a gene in the entire genome.

Here, these scientists seek to increase the production of one gene by introducing more copies of the same gene into the host genome. More copies leads to more expression, at least that is what the scientists hope for when they introduce more copies. How that affects the other genes in the host, may be more or less known. Genes have been around for about a billion years, as far as we know. Apples have been around for probably 34-40 million years, sometime after mammals came along.

I consider genes to be a storehouse of great wisdom and experience. I do not believe that we completely and safely understand the effects of genetically modified crops on our bodies, the environment or the host with modified genes. I don't think that we will gain that understanding anytime soon, not in my lifetime, and most likely, not in the lifetime of my children. Until we've had adequate safety testing of these foods, I will stay away from the Arctic Apple and look for organic varieties to eat. I encourage you and your friends to do the same.

To stay away from them, you will have to use some care and diligence. This GMO is protected by a patent. The gene modification can be performed surreptitiously upon many popular types of apples. The biggest problem is that GMO promoters are not so proud of their products as to put a label on them. They want the royalties from the patents, no doubt. But they are fearful that once the consumer apprehends that the product is genetically modified, they will avoid that product. So they want us to eat their product through deception, as if somehow, that will make everything alright.

Put a label on it so that we can decide for ourselves if we want to eat it. You cannot claim to operate in a free market without transparency and disclosure. To try to do so is a disservice to your customers. To pretend that anyone can comprehend millions of years of evolution to determine for sure if GMOs are safe, is not just a disservice to the consumer, it is dangerous.
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