To monitor changes in the serum concentrations of proinflammatory molecules in aged individuals, we conducted a five-year clinical survey in which we examined the serum levels of several important cytokines, including IL-1β, IL-4, IL-6, IL-13, IL-15, and TNF-α, to observe their association with the pathogenesis of sarcopenia. The gene discussed is IL15; the disease is sarcopenia.