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Posts tagged ‘Biology’

My girlfriend can clone DNA

Cool title, huh?

Aya just started working at a lab that does genetic engineering. She’s barely there a week, and already she’s cloned DNA. Here is a HUGE simplification of how it works (as much as my programmer’s brain managed to understand, with tons of errors I’m sure):

  1. Get a sample of DNA, this will be your template
  2. Prepare a solution with:
    1. Nuclease-free water – you want to make sure the water doesn’t contain any other DNA, or it might be cloned instead of the template
    2. Buffer solution – help create optimal conditions for the enzyme (more on this later)
  3. Add two specific primers, each is a completion of some known segment of the template. The size of each primer is usually about 24 bases.
  4. Add lots of DNTPs – these are the DNA monomers, the single building blocks of DNA
  5. Add a heat-stable enzyme such as Taq polymerase – this is the engine behind the entire reaction. It will latch on to the primers and run along the templates, adding DNTPs and building the DNA molecule.
  6. Put it all in a PCR machine
  7. Repeat about 30 iterations:
    1. Heat to 94-99 °C to make the DNA strands disconnect
    2. Cool down to 50-65 °C, so the primers can attach to the DNA strands
    3. Heat to 75-80 °C, which is the the optimum temperature for Taq polymerase
    4. The Taq polymerase finds the primers and then runs along the disjoint strands, collecting nucleotides from the solution and building the complementary strands

This process theoretically clones a segment of a single DNA molecule to about 230 identical molecules. Because the Taq polymerase sometimes fall off while building the strands, after the cloning she measures the length of the DNA molecules using Agarose gel electrophoresis. On that, another time perhaps.

Researchers Discover Gene That Blocks HIV

At Slashdot

Read one guys comment as he tries to explain the other techies why this is not yet a cure for AIDS:

*sigh* he’s saying that this is one thing we might change on the program. A patch for the human code, say.

We only have a small problem … the program is stored in a few trillion copies (all of which need to be changed), of extremely complex molecules (which we can’t reliable modify (we can’t even reliably read them) even when we have only 1 outside of the body).

Let’s say it’s this way. We have a patch for a flaw in your windows. Except it’s on paper. And the computers won’t boot until the patch is applied, so we need to take out the hard drive and *manually* change the bits on it. We have an electron microscope that *sometimes* has been used to change some random bits on the harddrive, which has once or twice resulted in a “mostly” correct change. Oh yes, and we have a billion computers, all of which still need to be operational after the change.

That’s where we are. We know what to change (or so we hope), it’s just … “a bit” hard to get to the bits.

איך משיגים תואר בביולוגיה

עדכון – אחרי שראיתי היום שמישהו אשכרה חיפוש “תואר בביולוגיה” בגוגל והגיע לדף הזה, החלטתי להעביר את המשחק לשרת יותר נורמלי מהמחשב הישן של ההורים שלי. נו שיהיה.

משהו שהכנתי מזמן בשביל איה.
עשוי לשעשע אתכם, אבל לא מובטח.

כנסו אם בא לכם

Matrix Proved Wrong :)

I wonder if this includes the Borg

25 Weirdest Animals

We have a Gremlin or two and a Jabba The Hut. Any more associations?

A good humor day

Don’t know, maybe because it’s the weekend, but this has turned up to be a good humor day:

  1. 20,000 Credit Cards
  2. XXX Star Wars
  3. Creationist Kit
  4. 101 Simpsons Quote

A Vaccine for AIDS!

The wet dream of medical researchers has been achieved – the vaccine for AIDS is here (ready for clinical tests, that is).

After being with a biologist for 2 years, I can’t help but thinking this is not necessarily a good thing. Sure, the vaccine might work on 99.9% of the people, but there a good chance the rest of the viruses will evolve and mutate into something even more resistant.

Aya here says that it might even become airborne, since the vaccine is now messing with parts of the virus DNA which have been pretty constant now.

And the worst part is that none of this is can be tested in the lab. You can’t really predict what the outcome of releasing this “cure” will be by testing in a lab.