User:Raj58/sandbox

Rebecca Jones, sophomore at Case Western Reserve University working on a project for a course in Darwinian Medicine. Darwinian Medicine considers the host's evolutionary background and the coevolution of any pathogen's that may afflict a particular host. Looking at the an organism's evolutionary history also allows insight into the ultimate cause of many non-infectious diseases like heart disease or autoimmune disease. While there exists a proximate explanation for many such degenerative diseases, knowing the ultimate cause may enable researchers to better treat such diseases.

Possible add to Multiple Sclerosis page:

Evolutionary perspective The complexity of Multiple Sclerosis makes it difficult to pin point the proximate causes for the disease, but the ultimate cause that has been suggested is relatively simple. The relationship between vitamin D deficiency and severity of MS symptoms is well documented. An appreciable difference in symptoms between males and females can be explained by differences in vitamin D metabolism; women evidently metabolize D more quickly and are therefore more susceptible to MS (Slavov, 2013). Vitamin D deficiency itself is caused by a mismatch between the amount of UVB exposure in a populations’ ancestral environment and their current environment. Near the equator not only is there a greater amount of exposure, but it is more consistent throughout the year. In more northern latitudes there is reported to be a 250% difference between seasons in the amount of UVB exposure possible to humans. The difference in UVB exposure is used to explain the evolution of lighter skin pigmentation, which has now been linked to an individual’s risk for MS. Lighter skin pigment does not interfere with the absorption of UVB light as much as darker skin, allowing for the synthesis of more vitamin D. Vitamin D is then used to regulate the immune system. The exact link between Vitamin D’s role in the immune system and MS is still murky, but the relationship between D, MS and exposure to Epstein Barr Virus has been well documented. Migration is not the only cause of the increased occurrence of MS. Cultural and social changes also play a role in that humans came first to rely on agriculture for their food, eliminating other Vitamin D rich food sources from their diet. This, compounded much later by industry demanding long hours working indoors away from UVB exposure is part of the most recent theory to explain the ultimate cause of the modern populations susceptibility to MS (Jablonski, 2013).