Amidst the evolution of the infectious pathogens, there is also one interesting factor that has been identified to be of biomedical significance, and this is the presence of recent rearrangements in the genetic makeup of human genome. These recent reshuffling of genetic material in cells of the human body are known as segmental duplications and are generally found to exist in at least two copies with at least 3% sequence differences, thus rendering these copies highly homologous based on >97% sequence identity.
Segmental duplications are also called copy number variants (CNVs) and a trove of research reports has indicated their role in disease and evolution. Redon and colleagues (2006) have estimated that approximately 1,447 CNVs exist in the human genome, and this in turn may serve as basis and explanation for variations in disease susceptibility and ethnic backgrounds. With this in mind, the evolutionary course of the diseases of hemophilia, porphyria and even HIV/AIDS can be better understood and handled by the biomedical field, as observed in the reports provided by Bagnall et al.
(2005) for hemophilia and Gonzalez et al. (2005) for HIV/AIDS. The article written by Shulman (2008) thus provides a simple view of how disease has affected the world for the past century yet the article may also mislead its reader by oversimplifying the events that have occurred, the activities that are currently taking place and the possible directions that the pathogens may take.
It is also important that the reader exercise caution in believing any information that has been printed for public dissemination because not all publications are reviewed by professionals who can pointed out the wrong or misleading information that may be included in the article. On a non-scientific point of view, the evolution of diseases has affected the world because it is also strongly associated with the changes that are occurring in the environment, including climate change, industrialization and the increase in the use of marine, land and air transportation and migration (Ferwerda et al.
, 2007). The increase in human activities have thus influenced the distribution of the pathogens across the globe and that specific infectious diseases that were earlier only observed in a certain country or global region may now be existing on other places around the world. Thus, the evolutionary claim of the article written by Shulman (2008) may be true in the general level yet the more important point is that the article may be misleading because it overlooks the more important issues of the current times.
References
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