20 January 2008

Nature vs. Nurture – The Unending Debate Part 2:

Genetics definitely play a large role in how we turn out in life, this is quite obvious. If you’ve ever seen identical twins or even just similar brothers and sisters you can often see similar features such as face shape or eye and hair colour, this is largely genetically based. However the evident problem here is that these siblings share quite similar environments, which makes it hard to really say that its all genetically based. However it is certain that some traits are far more genetically based than others and some are more within our control than others.

Often people seem to use genetics as an excuse. For instance someone may believe they have genetics which make them rather slow at thinking, and therefore decide to avoid an academic life as they don’t think they could possibly compete. Maybe they’re right, but there is also a large chance that even if they are right they could still be an academic through determination and vigorous application to studying. What seems to happen here is that genetics determine how well someone reacts to a certain environment, but obviously that isn’t the whole picture, because then it comes down to how often the genetics get the chance to interact with the environment. Allow me to try and explain with an example. Person A may have a good ability to gain muscle, whereas person B may have a below average ability to build muscle. However, if person A were to not exercise regularly and lead a rather lazy life whereas Person B kept quite fit and exercised regularly as well as eating well then Person B would most likely be quite well muscled. Most people would in comparing them think “ahh Person B has a unique ability to gain muscle”, but in fact this is simply not so, Person B in fact has a disadvantage in our comparison yet he still comes out on top due to simple persistence and determination.

Similarly you may have a genetic tendency to get diabetes or high cholesterol, but that in itself does not doom you to either. Rather it means that it is easier for you to get these medical problems and that therefore you may have to try a little harder to avoid them then people who are not so genetically prone. A healthy balanced lifestyle should keep you from ever developing the problems as while the genetic potential is there it is never being realised (and in this case it is a good thing that the potential isn’t being realised)! At the same time it is important that we realise the genetic limitations that are unique to each person. You certainly can gain more muscle than another person with identical genes by training, but maybe you will never be a professional Olympic-lifter as you simply lack the muscle and joint strength. Its not to say you couldn’t do Olympic-lifting and have fun and keep fit all while improving your strength, it is however to say that you must realise that if you have certain genetics you may not be able to go pro. Realising these limits need not be pessimistic, it is simply trying to put a realistic perspective on life. As http://www.maxwellsfitnessprograms.com/pdf/GENETICS%20OF%20A%20TRIATHLETE.pdf states:
“Accepting your genetics is by no means negative or limiting. It is quite the opposite. It is taking control of all the things you can to be the best you can be.”

It is important not to think of Genes as dominating the environment in a causal way. As http://genealogy.about.com/cs/geneticgenealogy/a/nature_nurture_2.htm argues: “Researchers on all sides of the nature vs nurture debate agree that the link between a gene and a behaviour is not the same as cause and effect. While a gene may increase the likelihood that you'll behave in a particular way, it does not make people do things. Which means that we still get to choose who we'll be when we grow up.”
Genes are dependant on the environment to be expressed, and the environment is dependant on genes to have a basis for expression. The two work together, they are mutually inclusive and intertwined, in reality the nature vs. nurture debate is a little silly as the two categories should never really be split as they are. Another article (http://goliath.ecnext.com/coms2/gi_0199-2820222/Blinded-by-Science-Nature-via.html), put this nicely in saying:
“We are indeed controlled by our genes, but they in turn are influenced by our experiences. Ridley says that the mapping of the genome "has indeed changed everything, not by closing the argument or winning the [nature versus nurture] battle for one side or the other, but by enriching it from both ends till they meet in the middle.”

In my opinion some things are simply more determined by environment or as the case may be genetics. If you’re fat you may be predisposed to gaining fat but you can most likely lose it through exercising and eating healthy. In contrast changing your eye colour could be rather more difficult! What’s more there also needs to be a distinction made between simple genes (genotype) and genes which have then also been set to a certain degree by early environmental influences (phenotypes). That is to say that everyone has a fat storing gene (although if your unlucky you may have a few more), but there tendency to store fat can be greatly effected by the diet of the mother while the baby is still prenatal. I remember reading a study about it in identical (presumably cloned) mice. Unfortunately I can’t seem to find it again. All I remember was that these mice were genetically identical and while they were all in their genetically identical mothers they were split into two groups. The control group ate a typical western diet high in saturated fat and sugar while the other group ate a much more healthy diet. Once both groups had given birth to the technically genetically identical groups of babies they put them all on the control group diet (the crappy American style diet) and they noticed that the original control group gained far more weight and had a far greater likelihood of developing diabetes and other problems on the rather unhealthy diet. The irony is that the other group didn’t even though they were genetically identical. This shows that the initial interaction with the environment sets the genes at differing levels (phenotype), and this is ultimately nearly as important as the genes themselves.

Regardless of all this essentially what I wanted to get around to saying was that we can’t change our genes, or how they are set. At least not at this stage, and the prospect of changing them certainly brings up odd ethical questions. But, we can at very least control our environment to a degree and make it as best we can to help how our genes express themselves in the future. If you unfit then you can exercise regularly and eat well and improve your fitness, regardless of your genes. Maybe your neighbour can get fit quicker than you but who really cares? The point is you’re doing something good for yourself, and that’s all that matters in the end.

I think this whole article about genetics brings up a really important issue relating to competition which essentially argues that we should only really compete with ourselves. Its often far to unfair to compete with other people as they may often not be on a similar level whether it be genetically or from environmental exposure. Thus instead of racing against the Olympic marathon runners times simply race against your own best time. Who cares if its ten times as long, if you improve your time only a little bit you are still improving, and in the end that’s all that matters. I suppose a nice way to conclude on genetics is to say that not everyone can be a professional athlete within a certain field, otherwise there amazing performances wouldn’t be seen as nearly as amazing as they are. But even so that is not to say that every singly one of us can work with what we’ve got and improve.

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