Pediatric Gastroenterology and Nutrition Unit, Carmel Medical Center, B Rappaport School of Medicine, Technion-Israel Institute of Technology, Haifa, Israel.
Med Hypotheses. 2011 Nov;77(5):773-6. doi: 10.1016/j.mehy.2011.07.034. Epub 2011 Aug 25.
Many human genes have adapted to the constant threat of exposure to changing environmental conditions. Balancing selection is the result of an initial stage of positive selection that favors the spread in a population of a new allele until selection opposes its fixation and balanced situation is established. It is suggested that the disadvantageous celiac patients survived the last two millennias echo-catastrophes by adapting to the extreme temperature changes and their consequences in Europe. Genetic selective diversity induced by changing environment, enabled the celiac population to survive. Such a genetic positive selection is represented by the HEF C282Y mutation of hemochromatosis, SH2B3 loci and the HLA celiac disease-associated repertoire, enabling the celiac to overcome iron deficiency anemia and micro pathogen richness, respectively. The increased incidence of those evolutionary events in the celiac patients is a recent phenomenon that occurred in the latest era of the modern human history. The present hypothesis can shed light on additional selective genetic adaptations, echo catastrophe-driven that are at the basis of autoimmune disease-affected population survival and current expansion.
许多人类基因已经适应了不断暴露于环境条件变化的持续威胁。平衡选择是最初的正选择阶段的结果，该阶段有利于新等位基因在种群中的传播，直到选择反对其固定并建立平衡状态。有人认为，过去两千年中，适应欧洲极端温度变化及其后果，使不利的乳糜泻患者得以幸存。由环境变化引起的遗传选择多样性使乳糜泻人群得以生存。这种由改变环境引起的遗传正选择由遗传性血色素沉着症的 HEF C282Y 突变、SH2B3 基因座和 HLA 乳糜泻相关库代表，使乳糜泻患者能够克服缺铁性贫血和微生物丰富度。乳糜泻患者中这些进化事件的发生率增加是一个最近的现象，发生在现代人类历史的最新时期。目前的假设可以揭示更多的选择性遗传适应，回声灾难驱动的，这是自身免疫性疾病受影响人群生存和当前扩张的基础。
