As we have learned, the phenotype of organisms is not only shaped by their genetic make up, but by environmental stressors during development as well. A recent study conducted by a group of population geneticists at Vetmeduni Vienna showed the effect of canalization on two separate strains of fruit flies, Oregon and Samarkand. Canalization is a sort of buffering system that, regardless of genetic mutations or environmental stressors, is able to keep an organism healthy and stable throughout its development. This mechanism of canalization allows development to occur without recognizable changes in the phenotype of the organism. The article explains that the researchers subjected the flies to different temperatures (13°C, 18°C, 23°C and 29°C) to analyze the variation in their gene expression. Their results showed that the flies have a sort of “genetic comfort zone” at 18°C where the gene expression in both strains was unaffected by the temperature. However, when the temperature was above or below 18°C the phenotypes of the flies were altered significantly. As Christian Schlötterer, one of the researchers studying the flies explains, “Once an organisms leaves the canalized range, those hidden genetic variations can be expressed and become visible.” This phenomenon is known as decanalization.
I found this article interesting because the idea of decanalization shows how environmental stressors such as diet, smoking, air pollution or stress can cause the expression of disease in human beings during development. I also found it interesting that diseases such as diabetes, asthma, depression and cardiovascular disease can be the consequence of genetic decanalization as researcher Greg Gibson proposes.
Primary source: http://journals.plos.org/plosgenetics/article?id=10.1371/journal.pgen.1004883
Secondary source: http://www.sciencedaily.com/releases/2015/02/150226141412.htm
This article was very interesting. I would have never thought that a slight variation in temperature would effect an organisms genetics.
ReplyDelete