7 Aug, 2008
Primates are ideal models because they have even greater homology than mice and they are extremely similar to humans in terms of their genetics, anatomical features and behavioural characteristics. But because primates are very much like humans, use of primates in research is fraught with ethical and moral considerations, thus any research conducted on primates has strict regulations which need to be adhered. In addition the cost associated with primate research is high, due to the special facilities required to handle primates. Because of cost issues researchers seldom use large sample sizes, which can also affect validity of the results, but they still feature in research because of the advantages associated with their use (Wekerle et al, 2006). Read the rest of this entry »
17 Jul, 2008
The use of animal models in research has benefited the area of science greatly; they have allowed us to generate cures and treatments for many diseases, in addition to helping us understand the genetic and physiological effects of harmful stimuli. However there is still an ongoing debate as to whether using animal models in research actually yields valuable results (Pound et al, 2004). Read the rest of this entry »
15 Jul, 2008
My interest in the art of medicine manifested itself from a childhood fascination into the workings of the human body. This fascination gradually developed into a passion for science and led me to undertake a degree in genetics. Throughout my degree I have found the rapid developments in the area of genetics and their implications in the world of medicine captivating. Read the rest of this entry »
12 Jul, 2008
This question is very difficult to prove, but theories have been postulated which attempt to explain why evolvability is a selectable trait. The difficulty surrounding selection and evolvability is that evolvability is a trait of lineages as opposed to individuals and this is where the difficulty regarding selection comes in.
Read the rest of this entry »
12 Jul, 2008
The ability of viral and bacterial pathogens to develop antibiotic resistance is a combination of natural selection and evolvability. The application of antibiotics to bacterial populations places them under a stressful environment. Bacteria and viruses are prokaryotes and therefore a lot of their genetic material is composed of RNA. RNA is genomically unstable and has a much higher mutation rate than DNA.
Read the rest of this entry »
12 Jul, 2008
During the early 1990’s scientists were more concerned about the actual resultant variation from Darwinian evolution, rather than its origin. Many scientists assumed that the origin of the variation was a product of Darwinian evolution. But recent evidence from simulations and observations of simple evolutionary systems has yielded results which prove that this is not the case (Nehaniv, 2003).
Read the rest of this entry »
11 Jul, 2008
Kimura (1983) is one of the key players of research into genetic neutrality and had a major role in its rise to prominence. Kimura referred to neutrality as genetic variation that does not result in change to the fitness of an organism. Moreover any change has to remain neutral in any environmental, genetic or physical condition.
Read the rest of this entry »
11 Jul, 2008
Robust biological systems acquire less phenotypic variation through environmental stressors or genetic damage as compared to less robust systems (Wagner, 2005). The ability of organisms to balance robustness and evolvability is the key for surviving a billion generations of varying environmental conditions with high levels of consistency (Lenski et al, 2006).
Read the rest of this entry »
10 Jul, 2008
Evolvability is recognised as the ability of an organism of any particular lineage to develop heritable phenotypic variation (Kirschner, 1998). Darwin’s theory of evolution is fundamental to Evolvability, as it is evolution which allows for the development of this heritable phenotypic variation. This variation could stem from natural selection or it could be from the result of acquired genetic change functions which can lead to novel functions.
Read the rest of this entry »
9 Jul, 2008
Werner syndrome is one of the best studies progeriod syndromes. It is considered an excellent model for human ageing (Cheng et al, 2007). Patients with Werner syndrome exhibit accelerated ageing and the common phenotypes associated with ageing. In this disease the WRN gene is mutated mainly through chromosomal translocations and this results in the production of a dysfunctional WRN protein (which has multiple roles in DNA metabolism).
Read the rest of this entry »