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Is ALS caused by floppy proteins?
The ALS Ice Bucket Challenge is no longer a thing, but sadly, ALS still is. Researchers at Berkeley Lab (and The Scripps Research Institute) led by John A. Tainer and Elizabeth Getzoff may have determined a molecular cause for ALS. It all focuses on a protein called superoxide dismutase (SOD).
Before we get into this, let's just review some molecular biology. A gene (which is a section of your DNA) serves as the blueprint for the production of a protein. Proteins are really long chains of subunits called amino acids. Just like the cord for your earbuds (which I almost called trendy before I realized Beats by Dre is the hot new ish these days), they get tangled up and take on a 3D structure that is almost always critical to that protein's job. Scientific convention is to list the protein in standard font (SOD) and the gene in italics (SOD1), which I will use below.
It's science time!
While genetic mutations in literature make all kinds of rad X-Men, in the real world, it can be more problematic... This research focused on mutations in the SOD1 gene that change the amino acid sequence of the protein. This changes the tangles in that cord analogy; in this case, it makes the tangles "looser," less compact, and more of a rod. This loss of structural integrity results in SOD proteins aggregating or clumping together; these same aggregates are found in affected cells of ALS patients, even those not linked to SOD1 mutations. Furthermore, one specific mutant of SOD called A4V is shown to aggregate very rapidly and is linked to very rapid progression of ALS.
I'm not an expert on ALS and the factors that cause it, but it seems like there still may be a large number of cases that aren't caused directly by SOD, though those cases are linked indirectly to that protein.
SOD1 mutations, the most studied factors in ALS, are found in about a quarter of hereditary ALS cases and seven percent of ordinary "sporadic" ALS cases.
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Aggregates of SOD with other proteins are also found in affected cells, even in ALS cases that are not linked to SOD1 mutations.
While this doesn't mean a cure is in reach just yet, I think this is a promising first step. If SOP aggregation is indeed the cause of ALS, then this presents a target for potential therapeutics to keep molecules of SOP from getting together or a treatment that will cleave apart these clusters. Additionally, the manifestation of SOP clumping means researchers may not have to develop specific treatments for each case (e.g., a genetic treatment for specific mutations to SOP1); potentially any treatment that applies to the protein could work for any genetic mutation.
Yay or nay for GMO?
Here's a generic opening line: the debate over genetically modified organisms (GMO) is ongoing, politically relevant, and contentious! A posse of UC Berkeley professors have presented the pros and cons of the issue to give you all the information in one convenient spot.
First, let's get one fact straight that may be surprising. There are several GMOs already in use in the forms of bacteria-produced insulin, select crops, and textiles.
So far, the federal Food and Drug Administration has rubber-stamped a limited assortment of genetically modified crops, including corn, soybeans, canola, alfalfa, sugar beets and cotton. Most are used to feed livestock or as ingredients in processed foods. (Genetically modified cotton is used to make clothing.) Also approved are limited varieties of produce, including papaya, squash, plums, cantaloupe, radicchio, tomatoes, potatoes and sweet corn.
As of yet, these GM fruits and vegetables are not commonly found in supermarkets.
Let's also look a little closer at a few cases of GMOs in use.
Most GM plants have been engineered to better fight weeds, pests and insects with fewer or even no spray chemicals-but whether there has actually been a decrease in the use of pesticides and herbicides has been the source of great debate. There are some viruses so destructive that certain species, such as the Hawaiian papaya, would have been wiped out without intervention.
[A] study found farmers in China, Argentina and India saw yield gains of from a quarter to more than a third higher when they used insect-resistant genetically engineered Bt cotton (cotton modified by the insertion of one or more genes from a common soil bacterium know as Bacillus thuringiensis, which organic farmers for years have sprayed on crops to fight pests). Estimated yield gains in the developed world are smaller, with the United States only expected to see a 10 percent increase in crop production, according to the study. ... As supply increases, price decreases.
Supporters argue that GMO crops could improve yield and productivity, allowing goods to be sold for cheaper; if not for the current limited use of GMO, the prices prices for various groceries would be an estimated 5–10% higher. By improving yield, we could help cut down on world hunger by increasing the supply of food or by creating crops that are more nutritious for inhabitants of third-world countries who don't have the luxury of choosing their organic cage-free quinoa.
Genetic engineering has also allowed for the creation of seeds that are naturally resistant to the herbicide Roundup, allowing that herbicide to be used to control the weed population; this is considered by some to be an advantageous property as Roundup is less toxic than other herbicides that were used prior to this GMO.
And, much like how the Hawaiian papaya was at risk of disappearing before GMOs, supporters fear that the beloved orange is under attack by citrus greening disease and every tool should be used to save it, including genetic engineering.
On the other hand, we have some experts who are opposed to GMOs. One concern they have raised is the effects that GMO will have on the environment:
GM technology contradicts [sustainable farming practices], [Claire Kremen] says—instead it's based on monocropping, a farming strategy that calls for growing one crop on a large piece of land, year after year. Monocropping is far more likely to cause the soil to lose its fertility, not to mention triggering a host of other ecological problems, including ground-water contamination and loss of natural pest control and pollination.
"My biggest concern is that GMOs are designed to fix one problem instead of looking at the whole," Kremen says, adding that the seeds, which often require ancillary products, are expensive for growers and can contribute to environmental hazards.
Creating plants that are magically impervious to one type of herbicide, then that starts a slippery slope where farmers will become overly reliant on pumping the same herbicide over their fields until weeds and pests naturally evolve their own resistances. Contrast this to traditional farming, where the farmer must alternate different herbicides in order to kill off the weeds; with ever-changing selection pressures (i.e., the thing causing deadly death), it takes longer for them to develop an herbicide resistance. Additionally, if farmers become reliant on herbicide-resistant GMOs, then that will make it easier for a few GM-capable powerhouses to establish a stranglehold on the industry.
Another concern that has been raised is the unwanted transfer of these modified genes to other organisms in nature. This could be either creating herbicide-resistant weeds (as explained above) that attack other farms or some type of horizontal gene transfer that results in other crops gaining these genes.
So... the conclusion is inconclusive. There's no proof that GMOs are harmful, but you can never 100% rule out that something could harm someone under the right circumstances after a long enough period of time. There are certainly valid points on both sides, so I guess all that can be said is: ¯\_(ツ)_/¯