The question whether environment and DNA effect phenotype and behaviour of an organism are being countered by another exciting area of research: epigenetics. This challenging area suggests an organisms emotional and physical fitness may be linked to its environment and the past conditions its parents were exposed to.
A paper called “Stress and transposable elements: co-evolution or useful parasites?” by Pierre Capy et al (2000) reported that transposable elements may respond to different external environmental signals and effect the hosts fitness to varying degrees. These effects may create more genetic variability for selection to choose from and improve the populations ability to withstand environmental change over time.
Parallels may be made to another journal article “Epigenetic variation and inheritance in mammals” by Vardhman Rakyan & Stephen Beck (2006). The article described how retrotransposons effected the expression of the agouti viable yellow allele in relation to coat colour and diabetes in mice. After exposure to a certain controlled environment, an unmethylated retrotransposon integrated upstream of the agouti gene and promoted expression of a yellow coat and a tendency to develop diabetes. However, another set of conditions caused methylation of the retrotransposon and it promoted expression of the wild type phenotype and normal health in the mouse.
Transposable elements by their design alone are quite radical and exciting. The fact they are being associated with the environment, parental effects and an organisms fitness, highlights their significance to future biomedical research.
Student: Gabrielle Ahern
Nr: 30010855
Primary Source:
Capy, P. et al (2000) “Stress and transposable elements: co-evolution or useful parasites?” Heredity 85: 101- 106
Secondary Source:
Rakyan V.K. & Beck, S. (2006) “Epigenetic variation and inheritance in mammals” Current Opinion in Genetics & Development 16: 573-577
Further sources of information:
Morgan, H.D. Sutherland, H.G. Martin, D.I. Whitelaw, E. (1999) “Epigenetic Inheritance at the agouti locus in the mouse.” Nature Genetics 23: 314 - 318
Websites:
Oxford English Dictionary Online
http://dictionary.oed.com.ezproxy.library.uq.edu.au/
