Genetic ancestry and population differences in levels of inflammatory cytokines in women: role for evolutionary selection and environmental factors

Background: Selection pressure due to exposure to infectious pathogens endemic to Africa may explain distinct genetic variations in immune response genes. However, the impact of those genetic variations on human immunity remains understudied, especially within the context of modern lifestyles and living environments, which are drastically different from early humans in sub Saharan Africa. There are few data on population differences in constitutional immune environment, where genetic ancestry and environment are likely two primary sources of variation.
Methods and Findings: In a study integrating genetic, molecular and epidemiological data, we examined population differences in plasma levels of 14 cytokines involved in innate and adaptive immunity, including those implicated in chronic inflammation, and possible contributing factors to such differences, in 914 AA and 855 EA women. We observed significant differences in 7 cytokines, including higher plasma levels of CCL2, CCL11, IL4 and...

研究背景：非洲地方性传染性病原体暴露所产生的选择压力，或可解释免疫应答基因中存在的独特遗传变异。然而，此类遗传变异对人体免疫功能的影响仍未得到充分研究，尤其是在与撒哈拉以南非洲早期人类生存环境截然不同的现代生活方式与居住环境背景下。目前关于体质免疫环境的人群差异的数据十分有限，而遗传祖先与环境因素很可能是该差异的两大主要来源。
研究方法与结果：在一项整合了遗传学、分子生物学与流行病学数据的研究中，我们对914名非裔美国人（African American, AA）及855名欧裔美国人（European American, EA）女性展开分析，检测了参与固有免疫与适应性免疫的14种细胞因子的血浆水平差异（其中包括与慢性炎症相关的细胞因子），并探究了此类差异的潜在影响因素。本研究观察到7种细胞因子的血浆水平存在显著差异，包括CCL2、CCL11、IL4等血浆水平更高的细胞因子……