According to Shenk, alpha-actinin-3 is a protein that drives powerful and fast muscle contractions and is the reason why researchers believe Jamaicans are able to be such talented runners. Yet "240 million" people in America and "597 million" in Europe who also have ACTN3. While Daniel MacArthur states, "there's simply no clear relationship" between ACTN3 and how successful runners are, to what extent does ACTN3 have on performance? (101). This is because according to Dan Peterson's brief report, there are various forms of ACTN3 produced depending on one's genes received from parents. How does this variation play into evolution with regards to athletic ability especially considering there are people out there who don't produce ACTN3 at all? Suppose there was a mutation, how could that affect a person, especially an athlete? Despite taking into consideration heredity, how could this potentially affect children compared to the environment also? (For example, Michael Jordan grew up and was actually rejected from basketball, yet he turned out to be a huge success. Is it due to his training or perhaps he happened to receive the desired RR ACTN3 variation that gave him his talents? This can be compared to Yao Ming whose parents were professional basketball players who had him trained as a child for basketball.)
Peterson's report can be read here: http://bleacherreport.com/articles/97666-athletic-gene-actn3-all-children-test-newborn-to-3
(Diana Liao - dianaliao3@gmail.com)
ACTN3 gene is in nearly all Jamaicans and in the majority of Europeans as well as Americans, but Jamaicans are much more successful at the sport of sprinting. The reason why Jamaicans are better is because epigenome changes can cause two different flowers to contain the same genetic coding. The epigenome plays a role on the expression of ACTN3 gene causing Jamaicans and Europeans and Americans to be so different trait wise. If the ACTN3 gene is what causes Jamaicans to run faster, through natural selection, that specific trait is advantageous and it is passed off to the offspring as the changes in epigenome can be inherited. Despite ACTN3 affecting the running trait, the environment does play a large role in the display of the traits. The Jamaican sprinting superiority could be societal based, where society develops pride in their ability to spring as well as the lack of motor transportation, therefore requiring the population to run. The more running is practiced; there will be changes in the epigenome, which affects the ACTN3 gene’s expression. Also, with more practice, the heart is able to deliver more blood to body cells per pump, hence more efficiently delivering oxygen and nutrients to the body cells which promotes them to grow and strengthen. America and Europe on the other hand, does have transportation, so people will be less likely to use ACTN3 and there will be less adapted to sprint. So despite the genes present in Jamaicans, Europeans, and Americans, what seem to ultimately determine traits is the environment, which turns on and off genes as well as enhancing transcription and translation of specific genes. The body is like a control center, where the environment and the genes interact with each other to determine what genes are expressed and the degree of those expressions. So because of the poor conditions in Jamaica, running has become necessary, therefore greater expression of the ACTN3 gene was produced, creating the perceived running superiority of Jamaicans. Michael Jordan’s case further proves the theory of environment affecting trait expression. When rejected from his varsity basketball team because of his height, motivation seems to have stimulated Jordan to improve in the skills of basketball. Training vigorously, from early morning work out plans to intense core training to practicing shooting ball non stop, motivation to prove one’s worth seemed to be Jordan’s motivation of increasing his basketball skill. It could be argued that Jordan’s epigenome was changed during his intense work out sessions, but what ultimately stimulated his great basketball skills was his environment, when the basketball team rejected him. If there was a mutation in the ACTN3, it doesn’t necessarily mean that is a bad thing. If through natural selection, the greater expression of ACTN3 will be passed to the offspring. If geographic isolation or reproductive isolation occurs and there is a mutation in the ACTN3, maybe the sprinting gene will be further enhanced. Therefore, a new species with similar features but containing the altered version of ACTN3 will be created, which is parallel evolution.
ReplyDeleteBing Zhao (bingzhao9@yahoo.com)
sources
http://www.nba.com/jordan/hoop_herecomesmj.html
http://www.time.com/time/magazine/article/0,9171,1952313,00.html