so winter is almost upon us here in the northern hemisphere, and with it comes fear mongering of the pandemic flu threat. go! spend money for a vaccine you probably don't need! it may not even help!
pandemic flu is basically a new strain of influenza virus that usually mutates to be able to infect humans, and is usually world-wide and highly virulent. they've happened in the past (1918 spanish flu) and tend to have a high mortality rate. researchers have been warning of the very real possibility of a world-wide pandemic occurring within the next few years. the most likely candidate is H5N1 virus, or avian flu. so vaccines have been developed and marketed for the past few years. the problem in my mind is the fear-mongering tactics advertisers for these vaccines use. yes, the pandemic is kind of imminent. yes, it will be dangerous. but medicine has come so far since the last pandemic, and especially in this country it will have less of an impact. i would be much more concerned for people in other countries who don't have the medical resources we do - that is where the flu will hit hardest. besides, the best was to avoid such a pandemic would be to stay home for a few weeks - just not being in public places will reduce the disease's ability to spread.
another issue is fear mongering about the LACK of vaccines available. they were in such high demand that the pharmaceutical companies actually ran out and had to ration them the first few years. but since the pandemic hasn't hit, demand has gone down so fear mongering has gone up. not everyone needs these vaccines; they usually make the patient sick (flu-like symptoms...) and may not even be for the correct influenza strand. they're a good idea to protect the young and old, and probably people who work with the young and old, but otherwise they are a bit superfluous. but pharmaceutical companies gotta get by right?
i've actually worked on a project evolving pandemic flu. it was a presentation to pharmaceutical companies about how vaccines are distributed and advertised. eye-opening... i learned that big companies have been encouraged to offer the vaccines to their employees and families, even outside the health professions and not specified for the young and old. yet another thing to spend money on right?
so overall, having vaccines ready for the imminent pandemic is probably a good idea. but we should take advertising and fear mongering about it with a grain of salt.
Tuesday, October 23, 2007
Sunday, October 14, 2007
conservation of species
i've recently started to work/volunteer/get credit for helping the US Geological Survey in their black-footed ferret conservation project. this is great work and giving me a wonderful connection with the organization, but has brought to my attention the conservation of species as an ethical issue. is it ethical for humans to interfere and save a species from extinction? even if it is not necessarily due to humans that the animal is headed towards extinction?
in my opinion, saving a species isn't really a bad thing. but because of the nature of evolution and natural selection, some species naturally evolve towards extinction. take the panda for example. humans have nothing to do with this animal's lack of sex drive. but they're big and cute and easy to raise money to save. as a small child i think someone gave me an "adopted panda" for my birthday.
another issue with saving a species from the brink has to do with genetic variation. 3 species in North America have been saved by capturing all remaining wild animals and breeding them captively - the red wolf, the California condor, and the black-footed ferret. the ferrets, for example, numbered 14 when they were removed from the wild, and though the population has been meticulously managed, inbreeding is unavoidable. so even though the actual current population is in the hundreds, the effective population (or the population of genetically dissimilar individuals that are breeding) is probably in the 20s somewhere. as another example; the entire population of cheetahs is so similar genetically, so recessive/homozygous, that they might as well be clones of each other.
in the case of the ferrets, humans definitely had an impact on their decline - habitat loss, systematic destruction of prey species (prairie dogs were viewed as pests) and plague arriving and spreading across the country were all because of the presence of humans.
so yes, i think saving species and maintaining as much biodiversity as we can (considering how much we have caused it to decline) is a good idea. mom always said i was a tree-hugger :)
in my opinion, saving a species isn't really a bad thing. but because of the nature of evolution and natural selection, some species naturally evolve towards extinction. take the panda for example. humans have nothing to do with this animal's lack of sex drive. but they're big and cute and easy to raise money to save. as a small child i think someone gave me an "adopted panda" for my birthday.
another issue with saving a species from the brink has to do with genetic variation. 3 species in North America have been saved by capturing all remaining wild animals and breeding them captively - the red wolf, the California condor, and the black-footed ferret. the ferrets, for example, numbered 14 when they were removed from the wild, and though the population has been meticulously managed, inbreeding is unavoidable. so even though the actual current population is in the hundreds, the effective population (or the population of genetically dissimilar individuals that are breeding) is probably in the 20s somewhere. as another example; the entire population of cheetahs is so similar genetically, so recessive/homozygous, that they might as well be clones of each other.
in the case of the ferrets, humans definitely had an impact on their decline - habitat loss, systematic destruction of prey species (prairie dogs were viewed as pests) and plague arriving and spreading across the country were all because of the presence of humans.
so yes, i think saving species and maintaining as much biodiversity as we can (considering how much we have caused it to decline) is a good idea. mom always said i was a tree-hugger :)
Sunday, September 30, 2007
cheese!!
that's right i'm talking about one of my favorite foods, cheese. see, thousands of years ago, it was discovered that if you added a tiny quantity of extract from the inner lining of the 4th stomach of a freshly-slaughtered calf to cow's milk, it would turn into cheese. this is how cheese was produced for a VERY long time; calf stomach extract. in the past 100 years, biochemists found the agent responsible for the cheesy transformation, it's called Chymosin. Chymosin is only produced in mammals that chew their cud, and only before they are weaned off mom's milk.
along comes DNA recombinant technology! the gene that codes for Chymosin production was isolated and inserted into bacteria. the bacteria-produced Chymosin is indistinguishable from its calf-produced counterpart (and hey, no baby cows need to die) and in 1990, it became the first approved product of DNA recombinant technology to enter the US food market. by 2004, over 90% of the cheese sold in supermarkets across the country was produced using bacteria instead of calf stomachs.
this is all well and good, but of course controversy has been sparked, as tends to happen when this kind of technology is applied to food.
1) If a company that uses the bacterial Chymosin is advertising "natural" production, do they have the right to claim that? what do we view as natural in this case?
one argument that i've heard for this and many other applications of this technology is that humans are natural beasts, so the things we do and what we create must be natural as a consequence of our being natural. by this argument, everything from nuclear power to stuffed animals is natural... right. i'm kind of indifferent on this except for false advertising laws. i, personally, don't consider this process really natural, but that doesn't stop me from eating it.
2) a lot of people are opposed to the idea of ingesting genetically engineered food products, and try to pressure the FDA to require labeling of them. in this case, since the calf-produced and bacteria-produced Chymosin are indistinguishable, no labels are required. both the FDA and food companies are well aware that a food product labeled "genetically engineered" will stop 50% or more consumers from buying the food.
i think the FDA is wise not to label these and other genetically engineered foods. as i've said before, humans have been selectively breeding organisms for a variety of purposes (but mostly food) and really, genetic modification at the DNA level is just a sped-up version of the same process. yes, bacteria is producing a mammalian-specific enzyme. and yes, they may as well be the exact same thing. the many companies using this process would suffer for integrating this technology into their business if the cheese was labeled, and that 50% (or more) of consumers would be "forced" by their aversion to genetic modification to buy the "natural" cheese, which now makes up less than 10% of cheese available and would drive the price up unreasonably.
3) organic food is allowed by the FDA to advertise that no product of recombinant DNA technology is used in their food (also that no genetically modified organisms are used). so cheese produced with bacteria Chymosin is not allowed to be called "organic." this means that organic cheese uses the cow product, making it unsuitable for strict vegetarians and vegans - but they are not necessarily labeled as containing animal products.
this is interesting, as the organic market generally caters to health-minded individuals, a good portion of whom are vegetarians. and hey, veggies like cheese too! but if the organic market starts labeling their organic cheese as containing animal products, they will lose a good part of their consumer base (at least for cheese). oh the dilemma! i think it should be labeled, vegetarians should know what they're eating. though i suppose that kind of conflicts with my opinion that genetically modified foods should NOT be labeled. oh well, thats how i roll.
along comes DNA recombinant technology! the gene that codes for Chymosin production was isolated and inserted into bacteria. the bacteria-produced Chymosin is indistinguishable from its calf-produced counterpart (and hey, no baby cows need to die) and in 1990, it became the first approved product of DNA recombinant technology to enter the US food market. by 2004, over 90% of the cheese sold in supermarkets across the country was produced using bacteria instead of calf stomachs.
this is all well and good, but of course controversy has been sparked, as tends to happen when this kind of technology is applied to food.
1) If a company that uses the bacterial Chymosin is advertising "natural" production, do they have the right to claim that? what do we view as natural in this case?
one argument that i've heard for this and many other applications of this technology is that humans are natural beasts, so the things we do and what we create must be natural as a consequence of our being natural. by this argument, everything from nuclear power to stuffed animals is natural... right. i'm kind of indifferent on this except for false advertising laws. i, personally, don't consider this process really natural, but that doesn't stop me from eating it.
2) a lot of people are opposed to the idea of ingesting genetically engineered food products, and try to pressure the FDA to require labeling of them. in this case, since the calf-produced and bacteria-produced Chymosin are indistinguishable, no labels are required. both the FDA and food companies are well aware that a food product labeled "genetically engineered" will stop 50% or more consumers from buying the food.
i think the FDA is wise not to label these and other genetically engineered foods. as i've said before, humans have been selectively breeding organisms for a variety of purposes (but mostly food) and really, genetic modification at the DNA level is just a sped-up version of the same process. yes, bacteria is producing a mammalian-specific enzyme. and yes, they may as well be the exact same thing. the many companies using this process would suffer for integrating this technology into their business if the cheese was labeled, and that 50% (or more) of consumers would be "forced" by their aversion to genetic modification to buy the "natural" cheese, which now makes up less than 10% of cheese available and would drive the price up unreasonably.
3) organic food is allowed by the FDA to advertise that no product of recombinant DNA technology is used in their food (also that no genetically modified organisms are used). so cheese produced with bacteria Chymosin is not allowed to be called "organic." this means that organic cheese uses the cow product, making it unsuitable for strict vegetarians and vegans - but they are not necessarily labeled as containing animal products.
this is interesting, as the organic market generally caters to health-minded individuals, a good portion of whom are vegetarians. and hey, veggies like cheese too! but if the organic market starts labeling their organic cheese as containing animal products, they will lose a good part of their consumer base (at least for cheese). oh the dilemma! i think it should be labeled, vegetarians should know what they're eating. though i suppose that kind of conflicts with my opinion that genetically modified foods should NOT be labeled. oh well, thats how i roll.
Saturday, September 15, 2007
predispositions?
allrighty. so in 1965 there was a study in a Scottish institution on mentally subnormal males. apparently most of the inmates had been convicted of violent crime. they found that 7 of the 197 (3.5%) had the karyotype XYY (called 47XYY Syndrome), significantly higher than the percentage found in the general public (.1%). these XYY males were also 6 inches taller on average than XY males, but had no other specific traits to identify them.
in 1968 a study was begun in Boston to screen newborn boys for the XYY karyotype, and follow up on the boy's development. in 1974 the study was opposed by several scientists and halted on the basis that it was based on preliminary observations and could be damaging the boys, as they could be unfairly labeled as violent or of subnormal intelligence. also, the parents had not been fully informed of the nature of the study.
so what is the best way to approach this question of the effects of the XYY karyotype?
i agree that the study should have been stopped, if only because the parents had not been fully informed. and it is not fair to pre-label the boys. but this is a nature-vs-nurture question in a big way. observing the development of the XYY boys would really be the best way to ascertain the effects of the extra chromosome, and a large number of subjects would insure that there would be several different nurturing environments. obviously not all perpetrators of violent crime have an XYY karyotype, but does the chromosome cause a predisposition for that kind of behavior? if an XYY boy is raised in a caring and safe environment are they still likely to turn violent?
well it turns out that since the 70s there have been other studies on the XYY syndrome. boys born with an XYY karyotype are not particularly more aggressive or violent, but don't respond as well to a poor nurturing environment as a normal XY boy. they may also have a higher chance of having a learning disability (up to %50) but the majority of males with the XYY karyotype live their life unaware of their extra Y chromosome.
in 1968 a study was begun in Boston to screen newborn boys for the XYY karyotype, and follow up on the boy's development. in 1974 the study was opposed by several scientists and halted on the basis that it was based on preliminary observations and could be damaging the boys, as they could be unfairly labeled as violent or of subnormal intelligence. also, the parents had not been fully informed of the nature of the study.
so what is the best way to approach this question of the effects of the XYY karyotype?
i agree that the study should have been stopped, if only because the parents had not been fully informed. and it is not fair to pre-label the boys. but this is a nature-vs-nurture question in a big way. observing the development of the XYY boys would really be the best way to ascertain the effects of the extra chromosome, and a large number of subjects would insure that there would be several different nurturing environments. obviously not all perpetrators of violent crime have an XYY karyotype, but does the chromosome cause a predisposition for that kind of behavior? if an XYY boy is raised in a caring and safe environment are they still likely to turn violent?
well it turns out that since the 70s there have been other studies on the XYY syndrome. boys born with an XYY karyotype are not particularly more aggressive or violent, but don't respond as well to a poor nurturing environment as a normal XY boy. they may also have a higher chance of having a learning disability (up to %50) but the majority of males with the XYY karyotype live their life unaware of their extra Y chromosome.
Thursday, September 6, 2007
genetic engineering
this one is not form a text book but from a class a friend of mine took years back. the class was Bio-Ethics and Society, taught by a genetics prof and a philosophy prof on the ethics of genetic engineering and other touchy scientific issues.
chickens have a nesting instinct, such that when they are kept in small enclosures like the kind egg farms use, without any nesting materials, they stress out and start plucking their own feathers to use for nesting. what if the gene for this behavior was found and could be switched off? (assume no adverse effects from such an alteration) the chickens would be less stressed in their small enclosures, there would be no extra cost for the egg farmers, and they wouldn't pluck out their feathers and be naked just to have something like a nest. should the gene be deactivated?
i would say yes, as this alteration would decrease the suffering of these animals and maybe they would produce more or better eggs when they're not stressed. also i imagine it would get cold to be a naked chicken. the argument against doing something like this is that it makes the chickens less chicken-like. or that genetic engineering is a bad idea in general.
the arguments against genetic engineering are usually something along the lines of "playing god" is a bad idea, and we could create a monster. a more legitimate claim in my opinion is that we don't necessarily know all the effects of turning on/off a gene or adding a gene from a separate species. as far as "playing god" goes, genetic engineering has been going on since we stopped being hunter-gatherers and started farming. selective breeding has given us large bananas without seeds, seedless grapes, wheat and barley with bigger and tastier grain, not to mention several domesticated animal species. creating a monster is still possible, but we don't need genetic engineering at the DNA level to do it. Caulerpa taxifolia is an algae that was selectively bred to thrive in aquariums, especially non-heated ones. it was accidentally released into the Mediterranean sea in 1984, and the cold-adapted algae thrived, to the point of choking native vegetation. the invasive species has since been found off the coast of California, and New South Whales, Australia. there are extensive measures taken to control the spread of the algae, but little can be done once it gets a foothold. this is certainly a man-made "monster" ecologically, and we are responsible for its behavior. but invasive and/or destructive species such as this have evolved naturally. so should a naturally occurring organism be controlled? plague is natural, should we be saving the prairie dogs from it? is this algae just special because we created it? where do we draw the line?
chickens have a nesting instinct, such that when they are kept in small enclosures like the kind egg farms use, without any nesting materials, they stress out and start plucking their own feathers to use for nesting. what if the gene for this behavior was found and could be switched off? (assume no adverse effects from such an alteration) the chickens would be less stressed in their small enclosures, there would be no extra cost for the egg farmers, and they wouldn't pluck out their feathers and be naked just to have something like a nest. should the gene be deactivated?
i would say yes, as this alteration would decrease the suffering of these animals and maybe they would produce more or better eggs when they're not stressed. also i imagine it would get cold to be a naked chicken. the argument against doing something like this is that it makes the chickens less chicken-like. or that genetic engineering is a bad idea in general.
the arguments against genetic engineering are usually something along the lines of "playing god" is a bad idea, and we could create a monster. a more legitimate claim in my opinion is that we don't necessarily know all the effects of turning on/off a gene or adding a gene from a separate species. as far as "playing god" goes, genetic engineering has been going on since we stopped being hunter-gatherers and started farming. selective breeding has given us large bananas without seeds, seedless grapes, wheat and barley with bigger and tastier grain, not to mention several domesticated animal species. creating a monster is still possible, but we don't need genetic engineering at the DNA level to do it. Caulerpa taxifolia is an algae that was selectively bred to thrive in aquariums, especially non-heated ones. it was accidentally released into the Mediterranean sea in 1984, and the cold-adapted algae thrived, to the point of choking native vegetation. the invasive species has since been found off the coast of California, and New South Whales, Australia. there are extensive measures taken to control the spread of the algae, but little can be done once it gets a foothold. this is certainly a man-made "monster" ecologically, and we are responsible for its behavior. but invasive and/or destructive species such as this have evolved naturally. so should a naturally occurring organism be controlled? plague is natural, should we be saving the prairie dogs from it? is this algae just special because we created it? where do we draw the line?
Monday, September 3, 2007
switched at the hospital and organ harvesting
these are the first of many scenarios from my genetics text book.
scenario #1
a family takes their daughter to you, a doctor, to get her blood-typed, among other things. you know that both parents are AB types, and discover the daughter is O, the only phenotype that couldn't be produced from these parents. she isn't adopted, so the only conclusion is that the children were switched at the hospital at birth. the girl's age is not specified, but she's healthy and old enough for them to be classified as a "happy family." do you tell the parents?
i would tell the parents, i would feel obligated as a doctor to be honest. i think the bigger question would be what the parents would do once they learned. the hospital would probably get sued, but would they try to switch the children back? i don't think so, but finding their real child might be a good idea, if only to let the other family know and perhaps swap medical histories. how often do you think that kind of thing happens though...
scenario #2
a young child is diagnosed with leukemia, the treatment for which is a bone-marrow transplant. finding a match for organ and tissue transplants such as this is difficult because of the 3 HLA incompatibility genes, each of which have 20-100 possible alleles. if the HLA genes in the transplanted tissue is not a close enough match to that of the rest of the body's, the body will attack it as a foreign object and it will be rejected. the young child has a rare combination of the 3 genes, and the parents are worried about finding a match in time. they decide to try and conceive a second child in the hope that it will be a match and could donate bone marrow to its sick older sibling. is this ethically right?
in my mind this is a clear and screaming NO. it isn't right to have a child so you can harvest its organs. in addition the procedure compromises the life of the new child, and doing such an operation on someone so young is dangerous. also there is no guarantee the younger sibling will be a match to the older, due to the nature of inheritance it could potentially have completely different alleles for the three HLA genes.
scenario #1
a family takes their daughter to you, a doctor, to get her blood-typed, among other things. you know that both parents are AB types, and discover the daughter is O, the only phenotype that couldn't be produced from these parents. she isn't adopted, so the only conclusion is that the children were switched at the hospital at birth. the girl's age is not specified, but she's healthy and old enough for them to be classified as a "happy family." do you tell the parents?
i would tell the parents, i would feel obligated as a doctor to be honest. i think the bigger question would be what the parents would do once they learned. the hospital would probably get sued, but would they try to switch the children back? i don't think so, but finding their real child might be a good idea, if only to let the other family know and perhaps swap medical histories. how often do you think that kind of thing happens though...
scenario #2
a young child is diagnosed with leukemia, the treatment for which is a bone-marrow transplant. finding a match for organ and tissue transplants such as this is difficult because of the 3 HLA incompatibility genes, each of which have 20-100 possible alleles. if the HLA genes in the transplanted tissue is not a close enough match to that of the rest of the body's, the body will attack it as a foreign object and it will be rejected. the young child has a rare combination of the 3 genes, and the parents are worried about finding a match in time. they decide to try and conceive a second child in the hope that it will be a match and could donate bone marrow to its sick older sibling. is this ethically right?
in my mind this is a clear and screaming NO. it isn't right to have a child so you can harvest its organs. in addition the procedure compromises the life of the new child, and doing such an operation on someone so young is dangerous. also there is no guarantee the younger sibling will be a match to the older, due to the nature of inheritance it could potentially have completely different alleles for the three HLA genes.
Saturday, September 1, 2007
a bit about this blog and me
So I decided to make this blog to discuss mostly science and ethics issues. I got the idea from my genetics text book, which has these ethical situation questions at the end of every chapter. I'll probably draw most of the scenarios from that, but some will be from other sources. I'll probably also be getting into other kind of science debates so feel free to bring things up.
i firmly believe that a grasp of spelling and grammar is no reflection of a person's intelligence.
now for the blog's namesake ethical debate: the runaway trolley. you are at the switch and a runaway trolley is headed towards a group of 5 people and will surely kill them all, unless you flip the switch to divert the trolley down another track, where it will only hit and kill one person; do you flip the switch?
most people say they would sacrifice one life to save 5.
another version of this is the fat man dilemma. in this scenario, instead of flipping a switch, you have to push a fat man in front of the trolley to stop it hitting the 5 people.
far fewer people say they would push the fat man to save 5 people. i think this is because flipping a switch is far less personal and feels less callous than pushing someone to their certain death.
other variations of this scenario:
-the 5 people are in your family or are your friends
-you know or are related to the fat man
-the fat man is on the tracks and the trolley is on a loop. so the trolley will hit the fat man either way, but if you flip the switch so it hits him first, the 5 people will still be saved
i firmly believe that a grasp of spelling and grammar is no reflection of a person's intelligence.
now for the blog's namesake ethical debate: the runaway trolley. you are at the switch and a runaway trolley is headed towards a group of 5 people and will surely kill them all, unless you flip the switch to divert the trolley down another track, where it will only hit and kill one person; do you flip the switch?
most people say they would sacrifice one life to save 5.
another version of this is the fat man dilemma. in this scenario, instead of flipping a switch, you have to push a fat man in front of the trolley to stop it hitting the 5 people.
far fewer people say they would push the fat man to save 5 people. i think this is because flipping a switch is far less personal and feels less callous than pushing someone to their certain death.
other variations of this scenario:
-the 5 people are in your family or are your friends
-you know or are related to the fat man
-the fat man is on the tracks and the trolley is on a loop. so the trolley will hit the fat man either way, but if you flip the switch so it hits him first, the 5 people will still be saved
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