ERV on Epigenetics

The discussion PZ and I had a couple of weeks ago sparked a lot of fun questions from viewers/readers. PZ covered a TON of the basics last week, so I figured I better step up to explain my view of epigenetics!

Epigenetics is inherited. Take agouti mice, for an example. If you alter how much folic acid a female mouse eats, you alter the epigenetic profiles of her grandpups. Folic acid starts off a chain reaction that leads to methlyation (silencing) of DNA, leading to different fur colors due to differential ‘silencing’ of a retroviral promoter and the ‘agouti’ gene.

No matter how much folic acid you feed those pups, their coats will not change color.

But that doesnt mean all epigenetic effects are carved into stone at birth!

Know how you always read those crappy AP articles about how broccoli has these magic anti-cancer properties? Its not magic. Its just (partially) epigenetics!

Broccoli has a compound in it called sulforaphane. Sulforaphane inhibits histone deacetylase (HDAC), which leads to the derepression of genes cancer cells turn off. Specifically, p21 and bax, the genes that say “STOP MULTIPLYING!!” and “DIE!!”– messages cancer cells dont want to hear.

Unlike folic acid–>fur color, sulforaphane–>HDAC can be altered via diet. If you eat a cup of broccolli sprouts, about 3 hours later there is a decrease in HDAC activity ~equal to drugs we give cancer patients.

The epigenetic research Im involved with is very similar, except with a different epigenetic modification and the activation of ERVs. Until we publish more, I really hesitate to blog much about it, because Im certain the woo-crew will have a field day. Im sure the same thoughts have already occurred to you all “U DONT NEED CHEMO U JUTS NEEDZ ORGANIK BROCCOLLIZ AND VITAMIN C AND MAGNETS 2 CURE CANSER!”

Thats not how it works, but it is part of a broader idea that cancer is not just caused by mutations in DNA or aneuploidy, but could also be caused/perpetuated by epigenetic screw ups. So you should eat your veggies. But dont ‘cure’ your cancer with veggies, okay? Promise?

Comments

  1. #1 John Dennehy
    July 27, 2008

    ORGANIK BROCCOLLIZ FTW!!!

    Great photo. I am going to have to steal that.

  2. #2 Yoo
    July 27, 2008

    This has got to be one of the few times a “miracle cure” food actually provides benefits beyond basic nutrition. Even better, now I have an idea of why.

  3. #3 Tyler DiPietro
    July 27, 2008

    So does epigenetics have an assortment of biochemical units, a la DNA for genetics? Histones certainly look like they fall into that category, but even this Wikipedia entry is a lot of info for me to absorb at once…

  4. Gah!!! Coolest post EVER!

    (Those mice are so cute! I know, you’re probably thinking I’m gross…but I have a Chinchilla, so I kind of love the rodents…)

  5. #5 Stacy S.
    July 27, 2008

    I don’t think there is a food that is better for you than broccoli.

  6. #6 llewelly
    July 27, 2008

    U DONT NEED CHEMO U JUTS NEEDZ ORGANIK BROCCOLLIZ AND VITAMIN C AND MAGNETS 2 CURE CANSER!

    Glad you reminded me about the magnets. I ran right out to the store and bought two of those little round ones – the kind that look just like black Vitamin C tablets. Tossed’m down with a tall glass of organic water. Take that, cancer!

  7. #7 wazza
    July 28, 2008

    Tyler: Epigenetics works by controlling what normal genetics does. It works in all sorts of different ways, usually by tagging the genes to say “don’t use this one”.

    It’s not coding for something, it’s coding to turn off other codes… if you get my meaning.

  8. #8 Tyler DiPietro
    July 28, 2008

    wazza: I think I might get it. So basically, you have a bunch of other biochemical influences on the DNA transcribes outside of the actual DNA itself?

  9. #9 Amplexus
    July 28, 2008

    Broccoli can’t cure cancer *Well!*

    Cureallkook all mad-libs

    …My *Distant relative* was told by her doctor *unlikely prognosis about impending doom*. All she did was *unsubstantiated claim* by eating fresh *Vegetable/fungus/mineral* and her *deadly disease* was *cured/reversed* and she’s still alive today after *unlikely span of time*
    ——————
    My question about epigenetics: Is it possible that I ingested some substance that will affect the phenotype of my children/grandchildren?

    Also ERV could you help me make sense of “sense/antisense” in DNA, I have a final coming up and I’m afraid i’ll memorize it backwards or just wrong.

  10. #10 manigen
    July 28, 2008

    Amplexus: What about pregnant women taking folic acid to prevent spina bifida? Wouldn’t that count as taking a substance to affect the phenotype of the offspring?

  11. #11 Stephen Wells
    July 28, 2008

    Llewelly: remember that swallowing ONE magnet is generally harmless but swallowing TWO can be fatal. You don’t want the two magnets attracting each other with some intestinal folds caught between them…

    This message brought to you by the Committee for Scientific Accuracy in Flippant Comments!

  12. #12 Kean Ashurst
    July 28, 2008

    If you don’t care for the taste of broccoli sprouts you can purchase a product developed for JHU called Vitalica. Check it out on the Web it’s a Great Product.

    It contains a mininum of 30mg of Glucoraphanin which hydrolizes to Sulforaphane.

    This raw material was used by JHU for an National Cancer Institue Grant to produce pure Sulforaphane the anti cancer drug.

  13. #13 Ranson
    July 28, 2008

    I’m reminded of Gerorge Carlin:

    Besides, I ain’t afraid of cancer…I had broccoli for lunch. Broccoli kills cancer. A lot of people don’t know that, it’s not out yet. It’s true. You find out you got some cancer…(click) get yourself a fucking bowl of broccoli. That’ll wipe it right out in a day or two. Cauliflower too. Cauliflower kills the really big cancers. The ones you can see through clothing from across the street. Broccoli kills the little ones.

  14. Ranson–
    I LOVED GEORGE CARLIN!!! Thanks for reminding me of our loss…sigh…(luckily he’s got DVDs and CDs for days! DAYS!)

  15. #15 John Kwok
    July 28, 2008

    Dear manigen,

    I think you should ask your MD about this, just to get an accurate answer from a doctor. However, I think you’re right with regards to spina bifida.

    Regards,

    John

  16. #16 Ranson
    July 28, 2008

    In regards to manigen and John K’s comments, I believe that folic acid is only useful in preventing spina bifida and the like when concentrations are at proper levels at conception. It likely does affect phenotype at that instance, but further folate supplementation does not have the same effect. That’s why the focus in actual medical recommendations is usually on women who may become or are planning to become pregnant.

  17. #17 Ranson
    July 28, 2008

    @ Chris

    Thanks — not a day goes by that I don’t have some fragment of a Carlin rant bouncing around in my head.

    It’s usually some variation on, “Road rage, air rage. Why should I be forced to divide my rage into separate categories? To me, it’s just one big, all-around, everyday rage. I don’t have time for fine distinctions. I’m busy screaming at people.”

  18. #18 Sili
    July 28, 2008

    Duh, Wells,

    You just take two identical magnets! Then they repell eachother!!

    :dislodges tongue from cheek:

    Why do people need excuses to eat broccoli? Or Brussel sprouts for that matter?

  19. #19 Bert Chadick
    July 28, 2008

    BROKLEES KILZ KANSUR?
    FAIL!
    BROKLEES MAIK BLEED KLOT. BLEED KLOT MAKE STROKZ.
    QED: BROKLEES KILLS

  20. #20 VWXYNot?
    July 28, 2008

    STOP MULTIPLYING and DIE! sounds like good advice for many people and occasions, not just for rogue cancer cells.

  21. #21 wazza
    July 28, 2008

    Tyler: Basically. But it’s also acting on the genetics directly by adding methyl groups which switch off the genes. These are the parts of epigenetics that can be passed on, because it’s something added to the gene itself.

    Manigen: In this case I think it’s not so much epigenetic as nutritious. Folate just helps the embryo seal the neural tube rather than leaving it open.

    Amplexus: Sense is the strand that makes sense. Easy enough. Antisense is the opposite strand, which is of course the exact opposite of the sense strand.

The site is currently under maintenance and will be back shortly. New comments have been disabled during this time, please check back soon.