8 ms·

Methylation and other base modifications (there are 20+ last I checked) are taught in upper-level biology courses. I guess the people who write biology texts co

by karcass 11y ago

Methylation and other base modifications (there are 20+ last I checked) are taught in upper-level biology courses. I guess the people who write biology texts consider this advanced material.

anigbrowl 11y ago
I don't understand why you wouldn't set that sort of thing out at the basic level, even if it were accompanied with 'we understand ACGT quite well, the others are pretty mysterious and we're not sure if they matter as much.' Seems a bit like teaching English by focusing only on spelling but omitting any mention of punctuation or grammar for the first few years. Of course we don't try to teach that all at once, but even very simple books use things like capital letters, commas, and periods so that kids get used to seeing them early on.
- streptomycin 11y ago
  Because it's just not very important at that point. If you covered all the exceptions and special cases in biology, Bio 101 would never end. It'd be kind of like teaching string theory at the same time as F=M*A.
  - anigbrowl 11y ago
    I strongly disagree. You don't have to go into detail about them, but knowing the fact of their existence is fundamental. If you think there are only 4 bases and then later find out that there are others, the first reaction t that is to feel short-changed about your previous education and stupid about all the new stuff you have to absorb. If you are told there's 4 bases that seem to deliver 99.9% of the action and another 20 or so which hardly get a look in, then you have a basic overview of the field. It'd be kind of like teaching string theory at the same time as F=MA.* So what? 'All matter is made up of very tiny things called atoms. There are 118 different types of atoms that that we know about, which have many interesting and surprising characteristics. Many atoms can be combined with each other to form molecules. All atoms seem to be made out of different combinations of subatomic particles, which are the very smallest things we have managed to measure, but which we only partially understand. Some scientists think subatomic particles are made out of even tinier structures called strings, but nobody has managed to prove that one way or the other.' You don't have to give a big long-winded explanation, but there's nothing wrong with sketching out in very general terms where the frontiers of our scientific knowledge lie. Likewise you don't have to teach small children comparative linguistics, but it's a good thing to make them aware early on that there are many different languages that originate in different countries. Not talking about the existence of things when trying to introduce a field really stifles curiosity, by obscuring the fact that that there are many interesting avenues of inquiry that have yet to be explored.
    - ars 11y ago
      > If you are told there's 4 bases that seem to deliver 99.9% of the action and another 20 or so which hardly get a look in How many blood types are there? Most people will say 4 (or 3, or 2 depending on how you define it). But there are actually far more of them, but the rest are rare or less important.
      - anigbrowl 11y ago
        What point are you trying to make here? It costs very little effort to mention the existence of many more types, even while acknowledging that most of the time you're going to run across the most common four types. On the other hand, suggesting that only 4 types exist is wrong. Anyone who is interested in biology is likely to waste a certain amount of time constructing theories based on a completely false premise, which is discouraging. That may sound trivial, but go look at festering debates involving a lot of pseudoscience, eg on the environment or evolution. People trot out arguments based on false premises as a matter of course, and I think that a you-don't-need-to-know approach to teaching science is part of the problem, because you end up with a lot of people who don't know what they don't know.
        ars 11y ago
        My point is just that there are huge number of biological corner cases that are skipped. It was just another example. > and I think that a you-don't-need-to-know approach to teaching science is part of the problem I agree actually, yet it's really hard to do for biology since it's not so much a science with axioms as archeology where you just look and see what there is. So there's no way to actually say one way or another "this is all the types". Maybe no animal like that has been found. Or maybe it could be done with another type, but no such animals exist - so do you say there is another type or not?
        TeMPOraL 11y ago
        So maybe it's time to teach, at some point in the class, that all those classifications in biology and other sciences are more or less arbitrary? That they're just approximations created for practical reasons, often adapted on the fly to fit a problem? Understanding this single concept would kill a lot of pseudo-scientific debates and prevent people from developing wrong ways of thinking, up to such ridiculous cases as modeling animals with Object-Oriented Programming you get in Software Engineering classes.
  - louthy 11y ago
    > It'd be kind of like teaching string theory at the same time as F=M*A. Would it be such a bad thing? I remember reading Richard Feynman's QED and thinking to myself: "I wish science lessons at school had started with this".
- jacel 11y ago
  We do understand a lot of the base modifications pretty well, but that's all they are - modifications. I agree that it could be useful to introduce students to the concept of epigenetics, of which base pair modifications such as methyl-cytosine are just one aspect. But it is an aspect that is no more important than all of the other epigenetic mechanisms - so it should be taught in that context. If you're interested in an overview of epigenetics, this is a great textbook chapter from Cold Spring Harbour Laboratory http://www.cshlpress.com/pdf/sample/epigen.pdf http://www.cshlpress.com/pdf/sample/epigen.pdf incidentally, James Watson, the co-discoverer of the structure of DNA, still works at CSHL.
- ende 11y ago
  Maybe. Undergraduate biology typically sticks to the same set of model systems (Krebs Cycle, for example) even across different courses (microbiology, biochemistry, etc.) in order to reveal deeper levels of complexity within some focused context. You never really get all the edge cases at once though. I think what most biology undergraduate programs need to add - and many have - is the equivalent of a "Programming Languages" course which adds a 'state of the diversity of the field' dimension to the usual micro-/macro- dimensions. CS (speaking very generally here) tends to either drill down into low level computation or up into high level abstraction, and Bio tends to drill down into sub-cellular/molecular or up into social/behavioral/evolutionary. In CS, a course in programming languages tends to offer a nice survey of the diverse extents of the field, and a similar survey of all of life's vast biodiversity would be a welcome addition to the undergraduate curriculum, imho.

by karcass 11y ago

Methylation and other base modifications (there are 20+ last I checked) are taught in upper-level biology courses. I guess the people who write biology texts consider this advanced material.

anigbrowl 11y ago

I don't understand why you wouldn't set that sort of thing out at the basic level, even if it were accompanied with 'we understand ACGT quite well, the others are pretty mysterious and we're not sure if they matter as much.' Seems a bit like teaching English by focusing only on spelling but omitting any mention of punctuation or grammar for the first few years. Of course we don't try to teach that all at once, but even very simple books use things like capital letters, commas, and periods so that kids get used to seeing them early on.

streptomycin 11y ago
Because it's just not very important at that point. If you covered all the exceptions and special cases in biology, Bio 101 would never end. It'd be kind of like teaching string theory at the same time as F=M*A.
- anigbrowl 11y ago
  I strongly disagree. You don't have to go into detail about them, but knowing the fact of their existence is fundamental. If you think there are only 4 bases and then later find out that there are others, the first reaction t that is to feel short-changed about your previous education and stupid about all the new stuff you have to absorb. If you are told there's 4 bases that seem to deliver 99.9% of the action and another 20 or so which hardly get a look in, then you have a basic overview of the field. It'd be kind of like teaching string theory at the same time as F=MA.* So what? 'All matter is made up of very tiny things called atoms. There are 118 different types of atoms that that we know about, which have many interesting and surprising characteristics. Many atoms can be combined with each other to form molecules. All atoms seem to be made out of different combinations of subatomic particles, which are the very smallest things we have managed to measure, but which we only partially understand. Some scientists think subatomic particles are made out of even tinier structures called strings, but nobody has managed to prove that one way or the other.' You don't have to give a big long-winded explanation, but there's nothing wrong with sketching out in very general terms where the frontiers of our scientific knowledge lie. Likewise you don't have to teach small children comparative linguistics, but it's a good thing to make them aware early on that there are many different languages that originate in different countries. Not talking about the existence of things when trying to introduce a field really stifles curiosity, by obscuring the fact that that there are many interesting avenues of inquiry that have yet to be explored.
  - ars 11y ago
    > If you are told there's 4 bases that seem to deliver 99.9% of the action and another 20 or so which hardly get a look in How many blood types are there? Most people will say 4 (or 3, or 2 depending on how you define it). But there are actually far more of them, but the rest are rare or less important.
    - anigbrowl 11y ago
      What point are you trying to make here? It costs very little effort to mention the existence of many more types, even while acknowledging that most of the time you're going to run across the most common four types. On the other hand, suggesting that only 4 types exist is wrong. Anyone who is interested in biology is likely to waste a certain amount of time constructing theories based on a completely false premise, which is discouraging. That may sound trivial, but go look at festering debates involving a lot of pseudoscience, eg on the environment or evolution. People trot out arguments based on false premises as a matter of course, and I think that a you-don't-need-to-know approach to teaching science is part of the problem, because you end up with a lot of people who don't know what they don't know.
      - ars 11y ago
        My point is just that there are huge number of biological corner cases that are skipped. It was just another example. > and I think that a you-don't-need-to-know approach to teaching science is part of the problem I agree actually, yet it's really hard to do for biology since it's not so much a science with axioms as archeology where you just look and see what there is. So there's no way to actually say one way or another "this is all the types". Maybe no animal like that has been found. Or maybe it could be done with another type, but no such animals exist - so do you say there is another type or not?
        TeMPOraL 11y ago
        So maybe it's time to teach, at some point in the class, that all those classifications in biology and other sciences are more or less arbitrary? That they're just approximations created for practical reasons, often adapted on the fly to fit a problem? Understanding this single concept would kill a lot of pseudo-scientific debates and prevent people from developing wrong ways of thinking, up to such ridiculous cases as modeling animals with Object-Oriented Programming you get in Software Engineering classes.
- louthy 11y ago
  > It'd be kind of like teaching string theory at the same time as F=M*A. Would it be such a bad thing? I remember reading Richard Feynman's QED and thinking to myself: "I wish science lessons at school had started with this".
jacel 11y ago
We do understand a lot of the base modifications pretty well, but that's all they are - modifications. I agree that it could be useful to introduce students to the concept of epigenetics, of which base pair modifications such as methyl-cytosine are just one aspect. But it is an aspect that is no more important than all of the other epigenetic mechanisms - so it should be taught in that context. If you're interested in an overview of epigenetics, this is a great textbook chapter from Cold Spring Harbour Laboratory http://www.cshlpress.com/pdf/sample/epigen.pdf http://www.cshlpress.com/pdf/sample/epigen.pdf incidentally, James Watson, the co-discoverer of the structure of DNA, still works at CSHL.
ende 11y ago
Maybe. Undergraduate biology typically sticks to the same set of model systems (Krebs Cycle, for example) even across different courses (microbiology, biochemistry, etc.) in order to reveal deeper levels of complexity within some focused context. You never really get all the edge cases at once though. I think what most biology undergraduate programs need to add - and many have - is the equivalent of a "Programming Languages" course which adds a 'state of the diversity of the field' dimension to the usual micro-/macro- dimensions. CS (speaking very generally here) tends to either drill down into low level computation or up into high level abstraction, and Bio tends to drill down into sub-cellular/molecular or up into social/behavioral/evolutionary. In CS, a course in programming languages tends to offer a nice survey of the diverse extents of the field, and a similar survey of all of life's vast biodiversity would be a welcome addition to the undergraduate curriculum, imho.