一项研究认为，怀疑能够保护亚洲和非洲裔不受疟疾影响的一个基因变种可能增加这些人对狼疮的易感性。
Kenneth Smith及其同事对从肯尼亚、香港和英国征集的将近5000位狼疮和疟疾患者进行了基因分型，并搜寻了受试者DNA的FCGR2B基因的一个变种，已知该基因变种在亚洲人和撒哈拉以南非洲人中间更常见。
此前的研究把这种这个基因的多态与可能增强狼疮易感性和疟疾抗性的一种免疫系统应答联系了起来。这组科学家报告说，香港狼疮患者的这种FCGR2B多态比对照组出现得更频繁，而患严重疟疾的肯尼亚儿童的这种基因多态出现的频率就比一般人群中的肯尼亚儿童更低。
这些结果符合已经被大家接受的观察，即与白人相比，狼疮在亚裔和非洲裔人群中更加流行。而且这些结果可能支持了作者的一种理论，即疟疾的高死亡率可能驱动着特定族群的自体免疫疾病易感性的增加。(生物谷Bioon.com)
生物谷推荐原文出处：
PNAS doi: 10.1073/pnas.0915133107
A defunctioning polymorphism in FCGR2B is associated with protection against malaria but susceptibility to systemic lupus erythematosus
Lisa C. Willcocksa, Edward J. Carra, Heather A. Niederera, Tim F. Raynera, Thomas N. Williamsb,c,d,e, Wanling Yangf, J. Anthony G. Scottb,c, Britta C. Urbanb,g, Norbert Peshub, Timothy J. Vyseh, Yu Lung Lauf, Paul A. Lyonsa, and Kenneth G. C. Smitha,1
Systemic lupus erythematosus (SLE) is a multisystem autoimmune disease more prevalent in people of African and Asian origin than Caucasian origin. FcγRIIb is an inhibitory Fc receptor with a critical role in immune regulation. Mouse data suggest that FcγRIIb deficiency increases susceptibility to autoimmune disease but protects against infection. We show that a SNP in human FCGR2B that abrogates receptor function is strongly associated with susceptibility to SLE in both Caucasians and Southeast Asians. The minor allele of this SNP is more common in Southeast Asians and Africans, populations from areas where malaria is endemic, than in Caucasians. We show that homozygosity for the minor allele is associated with substantial protection against severe malaria in an East African population (odds ratio = 0.56; P = 7.1 × 10(5)). This protective effect against malaria may contribute to the higher frequency of this SNP and hence, SLE in Africans and Southeast Asians.
