颅骨锁骨发育不良综合征患者的RUNX2基因突变检测分析

摘要

Objective: To analyze mutations of RUNX2 gene in a Chinese family with CCD. Methods: The proband and her parents were investigated in the present study. Radiological examination regarding osseous malformations was carried out over the entire body. Genomic DNA was extracted from whole blood, and the RUNX2 gene was amplified by PCR from genomic DNA. 100 healthy people were also included. DNA sequences were analyzed by using BLASTN (BLAST nucleotide) program. Results: Both the proband and her mother have typical CCD clinical characteristics, different from her healthy father. After BLASTN analysis, one novel mutation was identified in the proband and her mother, a heterozygous A to G transition mutation at nucleotide 478 in exon 2, which converted asparagines to aspartic acid at codon 160 (478 A>G,N160D). Conclusion: The N160D mutation is identified as a novel heterozygous mutation, which supplements the data of RUNX2 gene mutation research.%目的:检测鉴定我国一个颅骨锁骨发育不良综合征(CCD)家系RUNX2基因突变情况.方法:采用先证者查证法,对家系各成员进行全身健康状况及口腔专科检查,进行CCD诊断;抽取先证者及其父母外周静脉血,提取基因组DNA, PCR扩增RUNX2基因并测序,BLAST同源分析,同时检测100名健康人的相同位点,排除多态位点的可能.结果:先证者具有典型的CCD临床特征,其母亲亦为CCD患者,父亲则无相应临床表现;将先证者的RUNX2基因测序结果进行Blastn比较分析,在Exon 2上发现了一个A→G突变;实际测序图谱显示双峰结构(G、A),对其CCD母亲的基因检测表明,此突变来自母系染色体该基因478位点的基因突变;密码子AAC→GAC可能部分引起第160位氨基酸的改变,天冬酰胺(Asn,N)变成天冬氨酸(Asp,D);该突变型为478 A>G,N160D.家系健康成员同一位点显示G的单峰,即与野生型序列相同.结论:检测到的478 A＞G,N160D为新的基因突变位点,拓展了国内CCD基因层次的研究领域,为国内外CCD致病基因的突变位点数据库增添了新的资料.