αⅡbA477P(A446P)——发生于血小板无力症患者的新突变  

αⅡbA477P(A446P):A New Mutation Found in Patients with Glanzmann Thrombasthenia

作　　者：袁小瑜[1] 陈方平[1] 解勤之[1] 蹇在伏[1] 王光平[1] 

机构地区：[1]中南大学湘雅医院血液科,湖南长沙410008

出　　处：《医学临床研究》2004年第11期1238-1241,共4页Journal of Clinical Research

摘　　要：【目的】明确血小板无力症患者的基因缺陷 ,为进一步探讨其发病机理奠定实验基础。【方法】通过 4 0对引物对GT 5 7的αⅡb和 β3亚基基因的所有 4 5个外显子及其剪接点进行了全长的PCR扩增 ,然后对PCR产物进行了SSCP 聚丙烯酰胺凝胶电泳 ,发现αⅡb基因的 14号和 15号外显子 (Exon14 /15 )的PCR扩增产物出现了异常条带 ,对外显子 14 /15的PCR产物进行了直接测序。【结果】αⅡb基因外显子 14发生了点突变G→C ,导致氨基酸密码由GCT→CCT ,该突变位于αⅡb亚基cDNA第 14 30个碱基 ,导致第 4 77( 4 4 6 )位氨基酸残基由丙氨酸转变成脯氨酸 [αⅡbA4 77P(A4 4 6P) ]。【结论】通过查阅文献资料 ,αⅡbA4 77P(A4 4 6P)ObjectiveTo elucidate the genetic defects in patients with Glanzmann thrombasthenia (GT) and set up the experimental basis for further exploring the pathogenesis of GT. Genetic diagnosis was made for a patient GT-57. All 45 exons of αⅡb andβ3 subunit genes as well as their splicing sites were amplified through the whole length by PCR with 40 pairs of primer, then single strand conformation polymorphism-polyacrylamide gel electrophoresis (SSCP-PAGE) was performed with the PCR products. Abnormal bands appeared in the amplified product of exon 14/15 onαⅡb gene, its nucleotide sequences were analyzed directly.Point mutation G→C was found in exon 14 of αⅡb gene through SSCP-PCR combined with direct sequencing. The corresponding mutation of amino code was GCT→CCT. This mutation located in 1430th nucleotide of αⅡb subunit cDNA , resulting in the change of 477(446)th amino acid residue from alanine to proline[αⅡbA477P(A446P)].[Conclusion]After reviewing the data published on journals, this αⅡbA477P(A446P)mutation is identified as a new variant first reported in the world literatures.

关 键 词：血小板无力症 突变 

分 类 号：R558.1[医药卫生—血液循环系统疾病]