目前,国内外虽然有CTLA-4基因多态性与多种自身免疫性疾病之间相关关系研究的报道,但所显示的结果并不完全一致,其原因可能是因为存在种族、地区、遗传背景的差异所导致。如Yanagawa等[6]报道美国白种GD病人与CTLA-4多态性有较少的相关性,而在德国、加拿大及韩国人群中启动子多态性与GD显著相关[7,8]。国内周文旭等[9]研究发现CTLA-4基因启动子318(C/T)的多态性与GD的相关性是由于其与外显子1连锁不平衡,因此它是GD的一个遗传危险标志,但不具有独立易感作用。本研究结果显示GD组与正常对照组的基因型及等位基因频率相比较差异均无统计学意义,提示CTLA-4基因启动子318位点基因多态性与宁夏人群GD无明显关联。医.学.全.在.线www.lindalemus.com
CTLA-4是一种具有高度多态性的基因,我们在后续研究中,需进一步增加研究病例数,在基因、蛋白的表达和功能等方面进行更深入研究,以揭示此位点突变对GD作用和致病机理。同时,还要对CTLA-4基因的其他位点进行研究,从而揭示CTLA-4基因与GD发病及地域和民族之间的关联性。
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