
中华检验医学杂志 2019 年 4月第 42 卷第 4期 Chin J Lab Med,April 2019, Vol. 42, No. 4
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论著
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遗传性血小板无力症家系病例的突变分析
三例
甘芳宴 苗林子 屈晨雪 龚岩 陆遥 由然 高丙晶 李涛 郭帅
北京大学第一医院检验科 100034
通信作者:屈晨雪,Email:qucx2012@163.com
【摘要】 目的 运用生物信息学软件探讨 3 个遗传性血小板无力症家系的分子发病机制,为体外
实验提供依据。方法 对 3 个确诊遗传性血小板无力症家系进行基因分析。采用 ClustalX⁃2.1⁃win软
件分析突变位点同源序列保守性;采用 PolyPhen⁃2、PROVEAN、SIFT、MutationTaster 等软件分析突变
位点危害性;采用 spdbv 软件构建突变蛋白结构模型,分析突变位点对蛋白质结构影响。结果 3 个
血 小 板 无 力 症 家 系 发 现“ 新 突 变 ”为 ITGA2B :c.814G>C(p.Val272Leu)、ITGA2B :c.432G>A
(p. Trp144Ter)及 ACTN1:c. 2458A>G(p.Ile820Val)。 3 个 突 变 位 点 均 在 同 源 物 种 间 高 度 保 守 。
MutationTaster 预测 结 果 显 示 3 个 新 突 变 均有 可 能 致 病,PolyPhen⁃2 和 PROVEAN 预 测 结果 显 示
ITGA2B p.Val272Leu、ACTN1 p.Ile820Val 为良性的,SIFT 预测结果显示 ITGA2B p.Val272Leu 为有害
的,而 ACTN1 p.Ile820Val 为良性的。突变蛋白质结构分析显示 ITGA2B Val272 突变为 Leu 后,原有氢
键全部消失。ITGA2B Trp144 突变为 Ter 后形成仅剩 113 个氨基酸残基的截短蛋白。2 个突变均引起
GPⅡb 分子结构改变,导致 GPⅡb/Ⅲa 表达减低。ACTN1 Ile820 突变为 Val 后,仅保留 Ile820 与
Asp822 的氢 键,其余 氢键消失,引起 ACTN1 分子 结构改变 ,影响蛋白质功 能。结论 ITGA2B:
c.814G>C(p.Val272Leu)、ITGA2B:c.432G>A(p.Trp144Ter)、ACTN1:c.2458A>G(p.Ile820Val)突变均有
较高的致病可能性。
【关键词】 血小板无力症; 系谱;整合素 α2; 整合素 β3; 辅肌动蛋白; 突变
DOI:10.3760/cma.j.issn.1009⁃8158.2019.04.007
Mutational analysis of 3 Glanzmann′s thrombasthenia pedigrees
Gan Fangyan, Miao Linzi, Qu Chenxue, Gong Yan, Lu Yao, You Ran, Gao Bingjing, Li Tao, Guo Shuai
Department of clinical laboratory, Peking University First Hospital, Beijing 100034, China
Corresponding author: Qu Chenxue,Email:qucx2012@163.com
【Abstract】 Objective To explore the molecular pathogenesis of 3 Glanzmann′s thrombasthenia
pedigree by using bioinformatics software and provide evidence for in vitro experiments. Methods The
genetic analysis of 3 pedigree diagnosed as Glanzmann′s thrombasthenia was carried out. Clustalx⁃2.1 win
software was used to analyze the conservatism of mutant sites in homologous sequences. Bioinformatics
software such as PolyPhen⁃2, PROVEAN, SIFT and Mutationtaster was used to analyze the biological effect
of mutation. SPDBV software constructed the molecular structure model of mutant protein and evaluated the
influence of mutation on protein structure. Results The "new mutations" found in 3 Glanzmann′s
thrombasthenia pedigree were ITGA2B: c. 814G>C (p. Val272Leu), ITGA2B: c. 432G>A (p. Trp144Ter) and
ACTN1:c. 2458A>G (p. Ile820Val). All three mutations were highly conserved among homologous species.
Mutationtaster software showed that 3 new mutations were likely pathogenic. PolyPhen⁃2 and PROVEAN
software showed ITGA2B p.Val272Leu and ACTN1 p.Ile820Val were benign and SIFT software showed that
ITGA2B p.Val272Leu were likely pathogenic, while ACTN1 p.Ile820Val is benign. The result of SPDBV
software showed that the Val272 of ITGA2B was transformed to Leu, neutralizing all the original hydrogen
bond. The Trp144 of ITGA2B is transformed to Ter, resulting in the truncated proteins with only 113 amino
acid residues. All these mutations affected the molecular structure of GPⅡb, resulting in a decrease ofGPⅡ
b/Ⅲ a expression. When the Ile820 of ACTN1 is transformed to Val, onlyretained the hydrogen bond of
Ile820 and Asp822,neutralized the rest hydrogen bond, whichaffected the molecular structure and protein
function of ACTN1. Conclusion The mutations of ITGA2B:c.814G>C (p.VAL272LEU), ITGA2B:c.432G>
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