Possible 'Evolution' in Disease Resistence

In the case of genetic diseases, the type of genes a person carries determines what the person is at risk for. When determining the origin of the gene that indicates the risk of disease, researchers compile a list of factors that contribute to the makeup of the genetic code that is addressed in the afflicted person. Health factors include environmental exposure, diet, and activities that can alter the biology within oneself. Once these factors are established, tests are implemented to try the theories associated with the cause of the many different types of genetically derived ailments. These tests take a long time to establish a basis for treatment because many genetic diseases occur over time, so likewise, it will take time to find leads toward a cure. As with the case of the genetic disease called tuberculosis, time is one of the huge factors associated with the resistance to the disease, along with another emphasized factor, population density.


A news journal in London mentions a genetic variant that protects against tuberculosis which is prominent in populations that have a long history of city living. It was said that because ancient cities had poor sanitation and high population densities, diseases had an ideal breeding ground. It was also mentioned that because of natural selection, humans developed a resistance to certain diseases over time. In order to test this theory, researchers analyzed DNA samples from 17 different populations in Europe, Asia and Africa--the countries where there are cities that have been around for thousands of years. University College London professor Mark Thomas said that the results showed that almost everyone in these areas had this gene. A researcher says it's an example of human evolution at work. The authors of the study say that although the population in ancient cities have this gene, it's not necessarily because of the population density. It is said that all the ancient cities involved in Arabic invasions: Spain (711 to 1492) and India (12th century), have the gene. An ancient city population that wasn't involved in Arabic invasions (China), does not have the gene.

As said before, it takes a long time to establish a basis for treatment pertaining to genetic diseases. In order to find a lead in the search, one must look into the common factors associated with the links. In this case, all the ancient countries involved with an Arabic invasion at some point in time has the variant anti-tuberculosis gene. A study can be done with Arabs not only in their homelands, but in all countries where there is a high population of Arabs. It is possible that a lead can be found within certain ethnic groups. Arabic culture may contain aspects of livelihood that is preventative of particular diseases such as tuberculosis. Perhaps, if that is true, then other populations in other parts of the world can adopt components of the culture and strive towards an ailment free life. First, before it's safe to do so, it may involve the study of other cultures around the world as well and, perhaps, the fusion of different cultures that are preventative of disease. A social study can be involved in this search for a definite answer, because the study itself is indicative of a social problem. This problem may be solved by observing and testing the hypotheses of the cultural differences in every social group. It is possible that cultural differences, at the least, play a part in finding a key.