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    Genetically Modified Milk Cures Diarrhea, Could Save Millions Of Kids Annually
    By News Staff | March 13th 2013 04:01 PM | 17 comments | Print | E-mail | Track Comments
    Transgenic goats' milk modified to produce higher levels of the human antimicrobial protein lysozyme is effective in treating diarrhea in young pigs, proof-of-concept that food products from transgenic animals could also benefit human health.

    The researchers say this is the first study showing that goats’ milk carrying elevated levels of lysozyme, a protein found in human breast milk, can successfully treat diarrhea caused by bacterial infection in the gastrointestinal tract. Human diarrheal diseases claim the lives of 1.8 million children around the world and impair the physical and mental development of millions more and these findings offer hope that genetically fortified milk could eventually help prevent such diseases.

    In the study, researchers fed young pigs milk from goats that were genetically modified to produce higher levels of lysozyme, which occurs naturally occurs in the tears, saliva and milk of all mammals.  Although lysozyme is produced at very high levels in human breast milk, the milk of goats and cows contains very little lysozyme, prompting the effort to boost lysozyme levels in the milk of those animals using genetic modification.

    Because lysozyme limits the growth of some bacteria that cause intestinal infections and diarrhea and also encourages the growth of other beneficial intestinal bacteria, it is considered to be one of the main components of human milk that contribute to the health and well-being of breast-fed infants.


    Jim Murray, UC Davis professor of animal science and vet med population health and reproduction, photographed at the Dairy Goat Research Facility. Credit: Joe Proudman / UC Davis

    Pigs were chosen for this study as a research model because their gastrointestinal physiology is quite similar to humans, and because pigs already produce a moderate amount of lysozyme in their milk.

    Half of the pigs in the study were fed pasteurized milk that came from the transgenic goats and carried greater amounts of lysozyme -- 68 percent of the level found in human breast milk. The other half of the pigs were fed pasteurized milk that came from nontransgenic goats and thus contained very little lysozyme.

    The study found that, although both groups of pigs recovered from the infection and resulting diarrhea, the young pigs fed the lysozyme-rich milk recovered much more quickly than did the young pigs that received goats' milk without enhanced levels of lysozyme. Overall, the pigs fed the lysozyme milk were less dehydrated, had less intestinal inflammation, suffered less damage to the inner intestines and regained their energy more quickly than did the pigs in the control group. And, the researchers detected no adverse affects associated with the lysozyme-rich milk.



    “Many developing parts of the world rely on livestock as a main source of food,” said James Murray, a UC Davis animal science professor and lead researcher on the study. “These results provide just one example that, through genetic engineering, we can provide agriculturally relevant animals with novel traits targeted at solving some of the health-related problems facing these developing communities."

    The lysozyme-enhanced milk used in this study came from a transgenic line of dairy goats developed in 1999 by Murray, co-author Elizabeth Maga and their colleagues to carry the gene for producing human lysozyme in their milk.

    Published in PLoS One (no citation info yet)

    Comments

    And what will this do to the goats? Are these goats going to be special milk producing goats just for the humans who are dying of diarrhea? Won't they be rather expensive? yeah. Here's a clue: Give those people better health care, better amenities like clean water and etc., and the diarrhea problem will clear up! First world kids don't have those problems because they have clean water, good food and etc., and making some special expensive patented goats that can't even feed their own baby goats for those poor people in third world countries won't cut it. They would probably be glad to have any regular old goat!

    But I guess y'all would like a quick fix, wouldn't you? Quick fixes without thinking things through does nothing.

    Hank
    It doesn't do anything to the goats. But your objections basically invalidate every science breakthrough of the last 2,000 years.  Do you shop at Whole Foods?
    The article clearly states that the goats are genetically modified. They are genetically modified to make the milk more like that of another species, just to deal with problems that arose because of greed and politics. Therefore, you are full of it.

    Hank
    So that's a 'yes' on the organic food thing. Understood.
    You could genetically modify regular cows to produce more lysozyme. Using artificial insemination you could quickly build up the herd until all dairy com produced extra lysozyme. This could be done at low cost with government grants. The cows wouldn't be patented because the work is being done by a university not a business. Hopefully this would decrease diarrhea throughout the world and the cows would be no more expensive that regular cows to maintain. The cow's milk would first be used for infants, who are the most likely to die from diarrhea. Remember millions of people die each year from diarrhea.
    Of course we will have to follow your other suggestions as well like better health care, clean water, etc. Building clean water plants would be more expensive than genetically modified cows that reproduce themselves, but it should also be funded.

    Gerhard Adam
    This could be done at low cost with government grants.
    Whose government?
    Using artificial insemination you could quickly build up the herd until all dairy com produced extra lysozyme.
    What makes you think there is necessarily a herd? 
    Remember millions of people die each year from diarrhea.
    This isn't a cure.  It's a possible solution under certain conditions.
    Because lysozyme limits the growth of some bacteria that cause intestinal infections and diarrhea and also encourages the growth of other beneficial intestinal bacteria
    This is the biggest sticking point.  What bacteria is being targeted and which supposedly benefit?  Are we confident that we're dealing with the same bacterial environments [and human genetics] in all the different regions of the world?  It's important to note that more than half of the adult humans don't even possess the genes to process milk, so we can't simply assume that these results will translate equally to all different environments in the world.

    Is there any possibility that bacteria may come to tolerate these increased levels?  It's one thing if they are only exposed while breast-feeding, but if the lysozyme becomes prevalent in animal milk, then it suggests that these bacteria may develop a tolerance [or a means of coping] since it will be a long-term condition for them.

    There are still a lot of unanswered questions.  The most obvious; why are people being exposed to bacteria which cause diarrhea and what can be done to control that?  After all, that would be the more rational approach, instead of attempting to fix it after-the-fact.
    Mundus vult decipi
    "This could be done at low cost with government grants."
    "Whose government?"
    The U.S. Government and other governments sponsor research like this. Private groups like the Gates Foundation and the Ford Foundation also fund activity like this. Check out their websites.

    "Using artificial insemination you could quickly build up the herd until all dairy com produced extra lysozyme.
    What makes you think there is necessarily a herd?"
    If you start with one animal and start artificially inseminating other animals, you quickly end up with a herd.

    "Remember millions of people die each year from diarrhea.
    This isn't a cure. It's a possible solution under certain conditions."
    It's a partial preventive measure. I never claimed it was a total solution. I specifically said we must also pursue other methods.

    "Because lysozyme limits the growth of some bacteria that cause intestinal infections and diarrhea and also encourages the growth of other beneficial intestinal bacteria
    This is the biggest sticking point. What bacteria is being targeted and which supposedly benefit? Are we confident that we're dealing with the same bacterial environments [and human genetics] in all the different regions of the world?"
    I I think you raise some good points here. We may well find out that lysozyme enhanced milk doesn't work well in the real world on real people. You fund a thousand research projects, and relatively few end up eventually producing a worthwhile product. However the few that succeed more than make up for the failures.

    "It's important to note that more than half of the adult humans don't even possess the genes to process milk, so we can't simply assume that these results will translate equally to all different environments in the world."
    Diarrhea tends to cause a high death rate in infants, who are all able to digest milk. Also lactose intolerant people only have problems when they eat large amounts of dairy products. They also can eat yogurt and hard cheeses which are low in lactose.
    http://www.ncbi.nlm.nih.gov/pubmed/16373956

    "Is there any possibility that bacteria may come to tolerate these increased levels? It's one thing if they are only exposed while breast-feeding, but if the lysozyme becomes prevalent in animal milk, then it suggests that these bacteria may develop a tolerance [or a means of coping] since it will be a long-term condition for them.

    There are still a lot of unanswered questions. The most obvious; why are people being exposed to bacteria which cause diarrhea and what can be done to control that? After all, that would be the more rational approach, instead of attempting to fix it after-the-fact."
    Good points.

    "After thinking about this a bit, I don't think the process described makes any sense. Since bacteria can certainly become tolerant or inhibit the effects of lysozyme, then it makes the entire concept problematic.
    In order to not decimate the existing gut bacteria, that means that the lysozyme inhibitors must already be present, which suggests that they may be readily acquired, by the "bad" bacteria, given sufficient stimulus. It would be like giving antibiotics to bacteria while there are resistant strains also present and then wondering how the remainder acquired resistance."
    There are pathological bacteria that are lysozyme-resistant. This is a problem.
    https://www.google.com/#hl=en&output=search&sclient=psy-ab&q=lysozyme+re...

    Gerhard Adam
    OK, I admit I wasn't being very clear in my criticism.  My point is that many of the comments you're making seem to assume a relative degree of wealth on the part of the individuals involved. 

    So, my comment about governments was intended to convey the fact that we cannot presume what other countries are willing to subsidize, unless the assumption is simply that the "developed" world will do this on behalf of others.

    As for the comment about herds, again, we have to assume that many of these people may have few animals.  Artificial insemination may not be an option [especially if they can't afford it].  So, one cannot presume that herds even exist.

    The point about lactose intolerance seemed to assume that people had access to foods like cheese and yogurt, but we can't assume that people most likely affected by diarrhea of this sort, are in possession of these foods.  After all, if they can't obtain clean water, then there are obviously more fundamental problems here.
    Diarrhea tends to cause a high death rate in infants, who are all able to digest milk.
    This is where my argument comes full circle.  In those cases, the infants already have access to lysozyme because it is in human breast milk.  So, it would make little sense to take something that is already freely available and substitute it with genetically modified goat/cow milk.  As a result, my assumption is that the availability of such milk was intended for individuals other than infants, in which case the genetic issue of the digestibility of milk becomes relevant.
    Mundus vult decipi
    Gerhard Adam
    Another point I wanted to make regarding artificial insemination.  What makes this impractical is that apparently the genes have a Mendelian inheritance pattern, so it is equally likely that any calf born wouldn't have the gene.  When this is coupled with the requirement that the calf be female, the problem becomes significantly worse as a method of introducing such livestock into third-world poverty regions.
    Mundus vult decipi
    Gerhard Adam
    After thinking about this a bit, I don't think the process described makes any sense.  Since bacteria can certainly become tolerant or inhibit the effects of lysozyme, then it makes the entire concept problematic.

    In order to not decimate the existing gut bacteria, that means that the lysozyme inhibitors must already be present, which suggests that they may be readily acquired, by the "bad" bacteria, given sufficient stimulus.  It would be like giving antibiotics to bacteria while there are resistant strains also present and then wondering how the remainder acquired resistance.

    Mundus vult decipi
    UvaE
    There's also the issue that diarrhoeal diseases are not just caused by bacteria but by viruses and parasites(i.e gardia). The rotaviruses, especially, are one of the two most important contributing factors. 
    MikeCrow
    So, took me 2 seconds to google lysozyme, it seems cow milk is very low in lysozyme, 0.1 µg/ml, where human milk has 100 µg/ml.
    So, it seem obvious that engineering bovine milk to be more like human milk isn't going to be all that bad of a thing. Unless human milk is bad for humans.
    Never is a long time.
    Gerhard Adam
    So, it seem obvious that engineering bovine milk to be more like human milk isn't going to be all that bad of a thing. Unless human milk is bad for humans.
    Interesting comment, when you consider that no one has raised the point of whether it is actually good for cows.
    Mundus vult decipi
    Hank
    Are they feeding the transgenic goat milk to cows?
    Gerhard Adam
    The point was that Mike indicated that the cows would be genetically modified.
    Mundus vult decipi
    Gerhard Adam
    Actually it appears that this article is a bit late on the scene regarding this process.  Apparently goats and cows have been used for some time to conduct this research [at least as far back as 2006 for goats and maybe earlier].

    http://animalscience.ucdavis.edu/faculty/Murray/PDF/maga%202006%20in%20vitro%20bacteria.pdf

    http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0017593
    Mundus vult decipi
    Gerhard Adam
    This is the problem I have with this kind of media reporting.  The title and hype suggest that this will help "someone" in the third world.  It's not at all clear who is supposedly experiencing the diarrhea problem, but according to the title this is to help infants.

    As already stated, infants don't need the help, because lysozyme is naturally provided by human breast-milk, so this doesn't sound like much of a solution.

    It is telling what the research papers state:
    Despite the benefits that HLZ provides to breast-fed infants, mothers do not always desire to lactate and sometimes situations prevent lactation; therefore, the development of alternate sources of HLZ would be beneficial to infant health.
    http://www.plosone.org/article/info%3Adoi%2F10.1371%2Fjournal.pone.0017593
    Call me cynical, but suddenly the funding issue and who the intended market is becomes clear.

    Mundus vult decipi