- DNA technology questions
- Gel electrophoresis
- Polymerase chain reaction (PCR)
- DNA libraries & generating cDNA
- DNA cloning and recombinant DNA
- Hybridization (microarray)
- Expressing cloned genes
- Southern blot
- DNA sequencing
- Gene expression and function
- Applications of DNA technologies
- Safety and ethics of DNA technologies
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- Error in the video at about2:20: there is currently no vaccine for malaria - it is being researched and may be developed eventually using DNA technology.(20 votes)
- You are right :). There have been trials with the vaccines but none have produced sufficient immunogenicity.(5 votes)
- there aren't vaccines for malaria or herpes yet?? This seems like false information. Time2:24(9 votes)
- Actually, it depends on which herpes virus you are talking about. There is currently an effective vaccine against chicken pox/shingles ( varicella-zoster virus) however, there is no vaccine against HSV-1 (herpes simplex virus) and 2 which cause cold sores and genital herpes.
Agree with malaria though, there is currently no effective vaccine, just prophylaxis (i.e. chloroquine)(3 votes)
- AAMC also wants us to know DNA technology applications to human gene therapy, pharmaceuticals, and environmental cleanup. Anyone have good resources for those?(4 votes)
- Here are some ideas (but I think you're good to go based on what's here):
gene therapy: CRISPR cas can be used to insert gene in replace of a mutated gene (https://www.khanacademy.org/partner-content/bjc/2015-challenge/2015-life-science/v/bjc-crispr-cas-9)
pharmaceuticals: they already talked about vaccines and mass production of proteins like insulin which are done by pharma
- genetically modifying certain pests to make them infertile, to keep their growth under control (actually, they want to do this with the Zika virus!)
-genetically modifying certain bacteria so that they can degrade waste quicker!! (http://www.yourarticlelibrary.com/biotechnology/use-of-biotechnology-for-cleaning-up-our-environment/29370/)(8 votes)
- Isn't the ability to identify gene mutations and risks for disease (everything from diagnosing disease in-utero to the risks of developing certain hereditary cancers) something worth mentioning? It's a pretty big part of medicine today.(3 votes)
- i want to know about application of dna tech.in accordance with agriculture(1 vote)
- I would assume in regards to agriculture, AAMC would be referring to genetically modified organisms (GMOs). In the news today, there is a negative connotation associated with GMOs. However, they do offer benefits for farming. For example, if we want a corn plant to be taller, we can genetically insert a gene for 'tallness' into its genome. (Hypothetically, I'm not sure if this is actually a gene - but you get the idea). This is the basis behind our food industry today.(2 votes)
- Do CRISPR arrays/sequences include both the palindromic repeats and the spacers, or just the palindromic repeats? Moreover, are the palindromic repeats transcribed together with the spacers to produce crisprRNA?(1 vote)
- What techniques can i use to diagnose Huntington disease, taking into account that it is cause by an expansion of CAG repetitions on the gene in question? I can think that southern blot, and pcr followed with electroforesis gel would be viable options, what about chromosome banding?(1 vote)
- Two questions about the forensics applications:
1. Why would you look for STR's specifically on the Y chromosome when you could utilize the entire genome? Why are STR and Y-STR techniques distinct?
2. How long after the cell has been deposited (and therefore dead and degraded) can you accurately use genetic material for identification? Are we talking in terms of hours? Days? Weeks?(1 vote)
- So what are some applications of DNA technology? All right, well let's first look at medicine. So what are some applications of DNA technology in medicine? The two big things where recombinant DNA technology was first used was to create insulin and human growth hormone. So before the advent of recombinant DNA technology, insulin and growth hormone were really, really hard to manufacture. You basically had to isolate it from another human, purify it and then give it to patients. But with recombinant DNA technology you can basically just grow these proteins in E. coli. You can grow them in culture that of an E. coli bacteria. So this really has changed the way that medicine is practiced and it's really helped a whole bunch of people. Vaccines is another application of DNA technology. A while ago vaccines were made by first denaturing the disease and then after the disease has been weakened they would inject it into a human and they would hope that their immune system would be able to put up a fight against the weakened virus. And that way in the future if they were infected with that virus, they would at least have some kind of immune response towards the virus. The problem with this was that the patient would sometimes get the disease because you're injecting a weak virus but sometimes it wasn't weak enough. So with DNA technology, they can actually recreate the outer shell of the virus and inject that. So it's a lot more cost effective and it doesn't have the risk of actually causing the disease in the host. So this is much safer and is cheaper and it produces a better immune response. Some vaccines that we actually use recombinant DNA technology to create include the hep B virus and the herpes virus and malaria. So these are some applications of DNA technology in medicine. Another cool application of DNA technology is in solving crimes, so in forensics. So there are parts of the genome known as non-coding regions of the genome. And these regions can actually help forensic scientists identify specific individuals so they can look at things like short tandem repeats, STRs, and these are basically short sequences of the DNA like two to six base pairs long, and they're normally found in really high amounts. They're just these short repeats that are found in really high amounts and to varying degrees between different individuals. So if they actually sequence these short term repeats they could identify specific individuals given a DNA sample. They can also look at mitochondrial DNA. So mitochondrial DNA is inherited from your mother and it's found in really high amounts within an individual cell. So even if there is very little sample available, forensic scientists can analyze mitochondrial DNA in order to identify a potential suspect. Another technology that is using forensic science is Y chromosome typing, so that's Y-STR. And this is looking at short tandem repeats found on the Y chromosome. So DNA technology has helped scientists pick out individuals that have committed various crimes based on DNA samples that they were able to find. Agriculture is another field that has greatly benefited from recombinant DNA technology. For example scientists can now create crops that are resistant to insects and that are resistant to herbicides and can also delay ripening of the crops so that you can transport the crop from the farm to the store. So by doing this, you're basically able to create more crops to feed a growing population of individuals. And it also helps with the economy because then you've got farmers that are growing all their crops and if there was some sort of bacteria or virus that destroyed their entire crop, then that farmer would not get paid for that season so by transgenically modifying the crop so that it's resistant to specific things, then they're able to grow their crops, sell it, and feed individuals.