Tuesday, November 22, 2005

DNA restriction enzyme analysis workshop

Looking at the title, you might have wondered whether am I holding it or sth. lol. no.. In fact, I went to it last Friday, 18th nov. It was held in the Singapore Science Centre. I thk I can roughly remember the details of it:

Introduction: This workshop is mainly about restriction enzyme analysis and gel electrophoresis. In restriction enzyme analysis, specific enzymes are used to digest DNA, thus resulting in banding pattterns for comparisons and analysis. Gel electrophoresis separates the digested DNA fragments in an electric field to produce bands of DNA ( you can try guessing: DNA moves to the +ve or -ve side of the field?) . This technique is also the basis of DNA fingerprinting - often used in screening for diseases and solving criminal and paternity cases

09:30 - 11:30 a.m.: The workshop starts. Of course, the trainer introduces herself and went to introduce some facts abt DNA and also the micropipette and other apparatus in the lab. One micropipette costs abt S$500 and a bottle of agarose powder costs I thk S$800 if I'm not wrong. Ok, so then, we sort of practise with all the apparatus especially the micropipette. We did a run on sample dyes to get bands and we do case studies. After all that, we started on the real thing coz time will be needed for incubation in 37 degrees celsius environment in which that time will be our break. Okay, so it was like a case study thing again in which lots of bottles restriction enzymes were broken but onli 4 bottles were unbroken and we have to analyse and identify each restriction enzyme in the bottles. The 4 different restriction enzymes used by the company in the case study are EcoRI, HindIII, BamHI and NcoI. Lambda DNA (it's a bacteriophage which is a bacterial virus) was used as it is only 48, 502 bair-pair long, so is good for analysis. So four microtubes were labelled 1-4 and inside were different restriction enzymes. But of course, we have to make the agarose gel first. After the agarose was done, we have to wait for it to set. So in the mean time, we prepared the digestion mixture which is a mixture of the restriction enzymes, dye and DNA. The tubes were centrifuged to ensue that all the liquid in the tube settles to the bottom of the tube. And the tubes were placed in a 37 degrees celcius incubator/ water bath (I thk it's incubator) and time was also given to the enzymes for them to digest. Then, time for break.

11:30 - 13:30 p.m.: Break-time. Me and my friends had lunch at Macdonalds' and explored the science center. It was realli cool. I mean, its been like 4/5 years since I've been there haha. There was this human body exhibition, some physical science exhibition and of course we explored a little of the DNA trail since we had to go back for the workshop.

13:30 - 15:30 p.m.: The workshop continues. Now, the samples are ready for gel electrophoresis. 10 micro litres of each samples were loaded into four different wells in the agarose gel. We had to let it run for 45 min. In the mean time, we have to interpret restriction maps and calculate the sizes of the different fragments that each restriction enzyme will cut at specific sites of the lambda DNA. Then we did a drawing on the positions of the DNA fragments on a diagram of an agarose gel as these will be seens as bands on the actual agarose gel after it has been appropriately stained with ethidium bromide (highly mutagenic substance, must be handled very carefully and appropriately) and viewed. We watched some videos and very soon, the 45 mins were up. The gels were then taken for staining by the instructors and in the mean time, we did some more case studies. Soon after, the results of each group were printed and the enzymes were identified. The first tube is just the DNA sample with no digestion coz there was actually no enzyme inside. The second tube contains EcoRI, the third - HindIII and the last one is a mixture of EcoRI and HindIII. Yep. Then we did a group survey and it was the end of the workshop.

15:30-16:30 p.m.: One hour of exploration once again before it was time to leave for school.

It was a really fun and enjoyable experience althogether especially with the handling of the micropipette and other apparatus although I've handled a micropipette before when I was in secondary school, this time, I had longer time with it and more usage too. Not only that, I gain more knowledge about DNA profiling from the case studies. The case studies were realli interesting too. The videos shown were also very educational and enriching for us. This workshop reinforces my skills and knowledge in this area and not one minute was wasted ;). It was realli cool to be in the lab and wear the lab coat as well, makes all of us feel like scientists, haha.

Monday, November 14, 2005

High IQ in childhood tied to longer life

This is quite an interesting article as read from the title alone. It was from MSNBC health but they got it from Reuter so its essentially from Reuter. Anyway, so here it is: " NEW YORK - Smarter children may enjoy longer lives, the results of a new study suggest.

The study, which followed elderly adults deemed gifted by childhood IQ tests, found that the higher their early IQs were, the longer they lived -- up to a point, at least. The survival advantage began to plateau after a childhood IQ of 163, an intelligence level few people reach.

Dr. Laurie T. Martin and Laura D. Kubzansky of the Harvard School of Public Health report these findings in the American Journal of Epidemiology.

Though the reasons for the link between IQ and longevity are not clear, it does not appear to be merely a reflection of income and social position. As children, the participants were from affluent families and most were white. Yet childhood IQ was still a factor in their lifespan.

Similarly, in an earlier study of Americans with more varied childhood IQs and family incomes, Martin found that IQ was related to health problems independently of socioeconomics.

This, she told Reuters Health, suggests that IQ affects longevity among lower-income people as well.

As research has already linked IQ to mortality, the current study, according to Martin, was in part an attempt to see how far the IQ-health advantage extends. The researchers expected there to be a cutoff at which a high IQ no longer brought any extra health benefits.

And there was. But, Martin said, they were surprised at how high that cutoff turned out to be.

IQs of 163 or higher are not often seen; the average IQ score in the general population is 100 (by definition), and children who score above 130 are considered “gifted.”

Smarter children, healthier habits
The current study is based on data from 862 men and women followed since childhood, starting in 1922, until 1986. All had childhood IQs of 135 or higher, with the average being 151.

The researchers found that, up to the cutoff point of 163, participants’ risk of dying during a given period decreased as their IQ increased; for example, those with a childhood IQ of 150 had a 44 percent lower risk of death than those with an IQ of 135.

Though it’s not clear why childhood IQ itself might affect a person’s lifetime health, Martin and Kubzansky point to several possibilities. For one, these children may be more likely to take up healthy habits like regular exercise, while shunning health risks like smoking. They are also more likely to get high-paying, prominent jobs as adults, with all the advantages that confers.

And in general, Martin noted, IQ scores reflect a “set of skills,” like reasoning, planning and communication, that affect how people manage their health -- from talking with their doctors to dealing with a complex healthcare system.

Understanding exactly why IQ affects longevity, according to Martin, could ultimately help improve health and healthcare for everyone."


Yep, this is a rather cool article. But from what I think, to me, it just seemed to be an incentive for the very high IQs. For the average, their lifespan are average too. While those with high IQ live longer. If they are those genius kind, at least living longer means they can contribute to the society more too since they are cleverer than the average and they are independant of their socioeconomic status. So its quite fair. And anyway, some high IQ ones are those born with it so its somewhat genetic and if its genetic then probably the genes are "tougher" and so they live longer. Oh yea, and I watched this documentary yesterday on Channelnewsasia, and its abt "Global dimming", its actually happening now and the most impt point that they mentioned is that if we dun control global warming, if warm temp sort of overrides the cool temp, then by 2030 (from one of the models) , the world will warm by 4 degrees and by then, all the ice sheets from Greenland could melt, tropical rain forests could wither and burn from the heat, there'll be heat stroke and many more. By 2100, the world might warm by 10 degrees. So unless we do something, these predictions might be true. [ all the info should be like that, I was quite engrossed in the show to catch some of the words] The documentary called "A species' odyssey" is just great too. It's about the evolution of men and I think it started from Australopithecus anamensis (I didnt realli catch the name) yep and it was in two parts, and it went all the way to Homo Sapiens. Its one of the best documentaries I've watched so far.